PSYC 2200 part 2
What are some of the defining behaviors of mammals? (3)
- *play* - maternal behavior - vocal communication
What are some brain areas that contribute to the interpretation of visual context to facilitate object recognition? (2)
- *visual cortex* --> may group objects into categories based on physical appearance - *parahippocampal cortex (PHC)* --> sensitive to contextual relations based on the presence of other objects
How thick is the cerebral cortex? What is its total surface area?
- 1-4 millimeters thick - total surface area of about 1.5 meters squared
What is the resting membrane potential of rods?
- 44 mV
Explain the forefeet & hindfeet of raccoons (3)
- 5 fingers on their forefeet & 5 toes on their hind feet - soft skin on their digits (which do NOT have webbing between them) - top region of the digits is covered with short hairs, while the palms & soles are hairless
What are some characteristics of Von Economo neurons? (3)
- 5x denser in the right hemisphere than in the left hemisphere - appear later in fetal brain development (35th week of pregnancy) compared to other neurons - have been identified in many primate & nonprimate species that have advanced social interactions
What are some important cells in the acquired / adaptive immune system? (2)
- T cells - B cells
What forms of electrical conduction does a neuron use? (2)
- action potentials - graded potentials
What are some benefits of field research? (2)
- avoids limitations / confounding variables of the restricted lab environment - offers valuable insights about how physiological & behavioral phenotypes have adapted to specific environmental challenges (ex: snub-nosed monkeys have developed flat noses, excessive fur, & huddling behaviors to keep them warm in the winter)
Where is ACh produced? (2)
- basal ganglia - brainstem areas
Explain the difference between bats hunting for insects vs. bats that are in pursuit of specific insects
- bats hunting for insects emit a sonar signal with a long duration & narrow bandwidth to detect prey - bats in pursuit of insects emit more rapid, shorter-duration signals that alter the frequency modulation so it can be carried to the receiver (i.e. the bat), which can then detect the position of the insect
What are some reasons that the visual system is appealing to neuroscientists? (4)
- begins at a particular location & goes in a particular direction - easy to manipulate because you just have to change the light going in & then can see the impact on the rest of the system - makes sense to study vision because humans are a visual species - it has an interesting setup, in that it represents a 3D visual space in the brain's "language"
How do antagonists work? (3)
- block the receptor sites - increase the speed of neurotransmitter removal from the synapse - decrease the production of neurotransmitters
In what way is the trichromatic theory correct? In what way is the opponent-process theory correct?
- for the trichromatic color theory, peak sensitivity of the cones responds to 420 (blue-violet spectrum), 560 (yellow-green spectrum), & 630 nanometers (orange-red spectrum) - for the opponent-process theory, opponent cells that respond to 2 different colors have been found in the LGN & visual cortex
What can the cilia do in the nasal system? (2)
- recognize odors in the air that have been dissolved in the mucus - has machinery to transduce a signal from the chemical that will travel through the *cribiform plate* (a bone) to cranial nerve #1
What brain areas were involved in controlling eye movements in the study that examined the development of abilities on a response inhibition task? (2)
- right dorsolateral prefrontal cortex (DLPFC) - anterior cingulate cortex (ACC)
For a drug to be considered a safe & effective treatment option, what questions must be investigated & definitively answered? (5)
- route of drug administration (ex: inhalation, injection, oral pill) - absorption & distribution - binding - inactivation - excretion
Why has lots of work been done on the cerebellum? (2)
- simple circuits with lots of connections SO is a great place to study how synapses work - very easy access due to its location
What is are some benefits of reflexes? (2)
- speed - adaptive for survival because there could be terrible consequences of waiting until the appropriate brain circuits informed the appropriate muscle circuits to pull your hand away from a hot stove, for example
What did Penfield do? (2)
- stimulated the cortex of conscious human patients undergoing brain surgery to map out the sensory & cortical areas - his work culminated in the motor homunculus
What were the results of Penfield's study? (3)
- stimulation in the back (visual cortex) led the patients to see flashes of light - stimulation on the lateral sides (auditory cortex) led patients to hear sounds (specifically, memories of sounds, NOT random ones) - stimulation on the midline led patients to move their arms
What are some brain areas that play a role in habit formation? (2)
- striatum - frontal cortex
What are some examples of similarities across vertebrates? (2)
- structure of cortical neurons is similar in birds & humans - similarity in the hippocampal structures of kittens & humans, which indicates that there is also conservation in larger neural circuits
What are some studies investigating the influence of development & maturity on voluntary planned behaviors? (2)
- study examined the abilities of subjects of a variety of ages on a response inhibition task - study assessed the correlation of the actual size or thickness of cortical areas with intelligence
What are some studies showing the possible development of mirror neurons? (2)
- study found that adults & 1 year olds (but NOT 6 month olds) engage in goal-oriented eye movements when a toy is moved by a hand BUT NOT when it is moved automatically --> idea is that the ability to engage in behavioral competencies needed for eye-directed eye movements do not develop until 9-12 months - study found that 9 months olds show similar EEG patterns when they grasp an object as when they observe someone grasping an object
What are some studies that suggest that there might be a relationship between opportunities for children to play & the increasing prevalence of ADHD? (2)
- study found that boys with ADHD were less effective in their skilled movement patterns than their peers without ADHD - found that 85% of others reported that their children play & engage in active play less than they did as children, suggesting that the quantity & quality of play behaviors are changing rapidly
What were Bartholow's 4 important contributions?
1) 1st real experimental evidence that the human brain uses electrical activity & that the brain controls behavior 2) Fritsch & Hitzig's technique works in humans 3) similarity/continuity in organization of the brain across many species & within species 4) because of this^, can study animals to try to understand people
What are 2 divisions of the skeletal muscle fibers?
1) fast twitch muscle fibers 2) slow twitch muscle fibers
What are the 3 major functional sections of the cerebellum?
1) flocculondodular lobe 2) vermis 3) cerebellar hemispheres
What are the 5 structures in the limbic system?
1) fornix 2) septum 3) amygdala 4) cingulum 5) hippocampus
What are the 2 corticospinal tracts in the motor system?
1) lateral corticospinal tract 2) anterior corticospinal tract (aka ventral corticospinal tract)
What are 2 broad ways to study the complex nervous system that make it a bit simpler?
1) look at the *development* of the nervous system 2) look at the *evolution* of the nervous system
What are the 3 parts of the ossicles?
1) malieus (hammer) 2) incus (anvil) 3) stapes (stirrup)
What are 2 types of proprioceptors?
1) muscle spindles 2) Golgi tendon organs
What are the 2 main clusters of ACh receptors?
1) nicotonic ACh receptors 2) muscarininc ACh receptors
What are 3 specialized types of V1 neurons?
1) simple cells 2) complex cells 3) hypercomplex cells
What are the 2 major divisions of the PNS?
1) somatic nervous system 2) autonomic nervous system
What are the 2 major parts of the telencephalon?
1) subcortical systems 2) cerebral cortex
What are the 2 parts of the tectum?
1) superior colliculi 2) inferior colliculi
What are 3 characteristics of neurotransmitter release at the synapse?
1) synapse clean up 2) quanta 3) Dale's law
Von Economo neuron (spindle cell)
Bipolar neuron that is larger than a typical neuron & has 2 similarly sized dendrites extending from the cell body; these neurons & their connections within neural networks seem to play a key role in an individual's ability to make quick, intuitive assessments of complex situations
What color is represented by the shorter wavelengths?
Blue & purple
Synesthesia
Blurring of boundaries among senses (ex: seeing music)
What are some of the psychological effects of amphetamine?
Boosts alertness, produces a sense of well-being / confidence, diminished fatigue
Dendritic processes / dendritic branches
Branches of the dendrites; dendritic spines stick off of these branches, which extend from the dendrites
How do cones detect color?
By detecting the wavelength of the light coming in
How do humans get more functional units in the cerebral cortex?
By making more surface area for columns of functional units with the gyri & the sulci
How do neurons communicate with each other?
By secreting neurotransmitters that activate specific receptors on neighboring neurons
How did Brodmann divide the 6 layers?
By the cytoarchitectonics (i.e. what the cells look like)
How is the dermatome useful for doctors diagnosing shingles?
Can detect the origin of the shingles virus (Herpes zoster infection) by determining the specific dermatome affected
Prefrontal cortex (PFC)
Can enhance perceptual integration with other brain areas (ex: the thalamus, striatum, & cerebellum) during adolescence; involved in regulatory control
Retrograde dye
Can get picked up by the axon terminals & then be transported backwards up to the cell body (i.e. takes things going against the normal flow of neuronal processing)
What is a potential threat related to astrocytes?
Can give rise to *astrocytomas* = a relatively common form of brain tumor
Explain how there are practice effects for myelin
Can increase the amount of myelination through practice & use of those pathways because if you're using something more frequently, then it makes sense to devote more resources to making those signals faster
Ligands
Chemicals that bind to other chemicals; any molecule that acts in the body (ex: neurotransmitter)
What is the site of transduction process for the olfactory system?
Cilia
Ganglia
Clusters of neurons
Hue
Color
Cannabis / marijuana
Come from the dried flowering tops of plants rich in S-9 tetrahydrocannabinol (THC)
Explain the basic pathway of taste information
Comes into the taste bud through the taste pore & then are received by the taste cells, after which a signal is sent down through the gustatory sensory neuron, which sends information through the sensory ganglia
Mossy fibers
Comes up to the top of the purkinje cells, where the axon then branches into a T-shape & runs along the stacked plates of purkinje to interact with them; excitatory, glutamatergic
What does the basal ganglia generally do?
Communicates regularly with the cerebral cortex to contribute to the efficient execution of appropriate movements
What is the primary function of tracts & nerves?
Communication
Thalamus
Composed of 2 large egg-shaped structures, one in each cerebral hemisphere, that filter & direct sensory information to the appropriate higher area in the cerebral cortex; serve as an interface between lower down areas & the cerebral cortex (because info that goes to the cerebral cortex has to be routed through the thalamus)
Peptides
Composed of 3-40 amino acids
Neural circuits
Composed of axons & their terminal endings, dendrites & their spines, & the synapses they form; constantly change as the brain learns to adapt to new challenges as necessary for survival
What happens when the amygdala is lesioned in rats?
Comprised ability to fear stimuli
What happens when the amygdala is damaged in humans?
Comprised ability to interpret fearful faces in others
What do cells in the retina & LGN have?
Concentric receptive field
Corpus callosum
Connects the left & right hemispheres together; where the neurons cross over so each side of the brain can talk to the other
Evolution & development of different species' brains has been a _______________ process
Conservative
Sex chromosomes
Consist of an X & Y chromosome; combo inherited from the parents determines the sex of the offspring (female: XX, male: XY)
Neurofibrillary tangles
Consist of knotted threads of *tau (τ) protein*
Cytoskeleton
Consists of scaffolding by structures such as microtubules that aid in the transport of biochemicals within the cell; gives the cell form / structure & allows it to react to the environment
Motor unit
Consists of the α motor neuron in the ventral horn of the gray matter of the spinal cord, its axons, & the extrafusal muscle fibers it innervates
What does the nervous system require for muscles to function in a coordinated & effective fashion?
Constant feedback about the status of the muscles --> need to monitor levels of contracting & stretching so that the muscle is not damaged
Monoamines
Contain a single ("mono") amine group
Explain the new football helmets that have been designed to reduce impact to the brain in the event of collisions
Contain patches of air cells that act as shock absorbers when the player's head crashes into another player or the ground
Lysosome
Contains enzymes that break down molecules such as proteins & lipids
Nucleus
Contains most of the cell's genetic material, such as the genes that reside on the chromosomes
Midbrain (mesencephalon)
Contains nuclei where fine-tuned sensory & motor messages interact, enhancing the responsiveness of animals to complex environments
Postsynaptic membrane
Contains receptors for the specific neurotransmitters released by the synaptic vesicles in the presynaptic membrane
Organ of corti
Contains the area of the cochlea that contains the receptive cells (hair cells) for audition
_______________ of our lives constructs our personalized perceptual realities
Context
What can affect (positively or negatively) rates of cellular proliferation (i.e. neurogenesis)?
Context (internal & external conditions) Ex: in rodents, running increases neurogenesis
The brain has _______________ ____________ over the body. What does this mean?
Contralateral control - means that one side of the brain controls the opposite side of the body
Explain the number of glial cells, in comparison to neurons
Contrary to traditional beliefs (which assumed that glial cells outnumber neurons), isotropic fractionation has shown that the # of glial cells varies drastically by brain structure --> in total, though, the number of glial cells in the brain is approximately equal to the # of neurons in the brain
What does lateral inhibition emphasize?
Contrast enhancement
Area V5 / medial temporal area
Contributes to the perception of motion
Central pattern generators
Control networks of neurons that spontaneously generate patterns of activity, such as walking
What are the ipsilateral fibers from the anterior corticospinal tract important for?
Controlling the muscles of the core/midline of the body
Place theory
Different places along the organ of corti code for different frequencies
What distinguishes sex chromosomes from regular chromosomes?
Different shape
What is a hallmark feature of the nervous system?
Differentiation
Functional neuroanatomy
Differentiators between what we know about the anatomy & what a person is feeling (i.e. their symptoms)
Pathogens
Disease-causing agents
Explain some brain differences in rodents that show how important sense of smell is for them (3)
Disproportionately large: - size of olfactory bulbs - size of VNO - proportion of genome devoted to olfaction
_____________ to the axon hillock matters for which synapse can actually make a change in the postsynaptic cell
Distance
What happens at 4 weeks, in terms of prenatal brain development?
Distinctive brain categories (ex: forebrain, midbrain, & hindbrain) begin to appear
Ernst Mayer
Distinguished between 2 different contextual variables that influence human behavior: ultimate causes & proximal causes
Central sulcus
Divides the frontal lobe & the parietal lobe
Central sulcus
Divides the primary motor cortex in the frontal lobe (specifically, the pre-central gyrus) from the somatosensory cortex in the parietal lobe
Spinal tap
Doctors take a bit of the CSF from lower in the spinal cord & use it to look at its composition & make a diagnosis
Which 2 types of transporters does cocaine bind more strongly to?
Dopamine & serotonin transporters
What brain view did Fritsch & Hitzig see when they were doing their experiment on dogs?
Dorsal view
Who identified the acquired / adaptive immune system? What did he do?
Dr. Edward Jenner --> acting on an idea that exposure to small amounts of a pathogen enabled the body to build resilience against an immunological threat, he injected a young boy with cowpox virus & then with smallpox pus, which led the boy to NOT contract smallpox (1st *vaccination*!)
Explain what happens when botulism toxin (botox) blocks the release of ACh
Flaccid paralysis --> makes it so that the muscle on the other side of the synaptic cleft can NOT contract, leading to relaxation of the muscles (ex: no wrinkles in the face)
Cochlea
Fluid-filled area in the inner ear that is shaped like a snail & is located directly under the temporal lobe; transduces the vibration signals into a neural code
Psychophysics
Focuses on the specific physical qualities of a sensory stimulus & one's perception of that stimulus
What activities cause the most concussions in children? (2)
Football & cycling
What is an example showing that some language might be located in the right hemisphere?
For Patient P.S., when the word "girlfriend" was flashed to his left visual field & therefore right hemisphere, he could NOT verbally say the name of his crush BUT could spell it out with scrabble tiles --> this suggests that even though verbal language is not possible in the right hemisphere, there is a form of language that is possible through gesturing & moving with his left hand
Where are T cells formed? Where do they mature?
Form in the bone marrow; mature in the thymus
MDMA (ecstasy)
Form of amphetamine
John Hughlings Jackson
Formally defined the symptoms of epilepsy --> "seizures accompanying epilepsy are characterized by abnormal neural discharge (i.e. atypical synchronized excitation of a population of neurons)"
Psychoneuroimmunology
Formally established the connections among psychology, neuroscience, & the immune system
Bony fish
Fossil fish that are some of the earliest vertebrates
What did Sir David Ferrier do?
Found specific motor areas of the brain in monkeys
What is a study showing multisensory integration?
Found that 23% of the same neurons responded to BOTH the sight of a person ripping paper & the sound of ripping paper
How do the semicircular canals work?
Hair cells stick up in these canals into a gel-like fluid --> when you move in one direction, this gel sloshes back & forth & bends the hair cells so they deflect, thus opening up ion channels & causing the hair cells to send a signal saying that you moved in a certain direction
Explain the method of the study investigating the effects of maternal exposure to indirect ("bystander") stress on prenatal neural development
Half of the pregnant rats were exposed to bystander stress, while the other half were not; once born, the pups developed for 21 days & then their brains were examined
Explain what happens when the electrical disturbance reaches the axon terminal?
1) the axon terminal / terminal bouton gets very positive 2) the positive membrane potential activates voltage gated calcium (Ca2+) channels, which have a conformational change that allows calcium (normally higher on the outside of the cell) to come into the cell 3) this calcium influx triggers the docking of vesicles onto the membrane, which they merge with to release their neurotransmitter contents into the synaptic cleft
What were Fritsch & Hitzig's 3 main discoveries?
1) the brain is *electrically excitable* 2) there is some *regional specificity* in the brain (because they only saw movement when stimulating the middle of the brain & the body parts that were moving changed as they moved the electrical stimuli around) 3) these results are *replicable* (i.e. the same place in the brain controls the same body parts)
What are the 2 parts of the metencephalon?
1) the pons 2) cerebellum
What are 3 ways that we can localize sound?
1) time concept 2) phase difference 3) loudness
What are the 2 major steps in transmission of genetic information?
1) transcription 2) translation
Reflexes
Hardwired, simple circuits Ex: if you touch a very hot surface, a pain impulse will come into the dorsal root ganglia, synapse in the dorsal horn, & then send info up to the brain to process & understand it & send info down to move your hand away BUT before it has the chance to get up to the brain, there will be a reflex that will move your arm away before you are even consciously aware of the fact that you burned yourself
Supplementary motor cortex
A cluster of cortical areas that helps to guide the execution of complex behavior; plays a key role in self-initiated (voluntary) movements as opposed to responses triggered by external events
Unipolar neuron
Has 1 process extending from the cell body that divides into an axonal & dendritic segment
Bipolar neuron
Has 2 processes extending from the soma (a dendrite & an axon)
Basal ganglia
A collection of interconnected nuclei that surround the thalamus & regulate movement; series of several structures that coordinate together in a complex circuit
What happens when bipolar cells are excited, in terms of lateral inhibition?
A corresponding horizontal cell in the retina is activated, which then inhibits adjacent bipolar cells in a graded manner laterally across the bipolar cellular field
Insula
A cortical area involved in processing information from both internal & external sources
What does survival depend on?
A cost/benefit analysis between safe but restricted resources & riskier but more plentiful resources
Choroid plexus
A dense collection of small blood vessels in the ventricles; produces CSF
Novocaine
A derivative of cocaine used for local anesthesia; works by reducing the cell's permeability to sodium ions, thereby decreasing nerve conduction & providing anesthesia & analgesia
Transcranial magnetic stimulation (TMS)
A perturbation technique that disrupts/perturbs neural processing via the placement of a magnet over the cortex & the subsequent administration of brief electrical currents in a specific region of the cerebral cortex
Estrus
A phase of the reproductive (estrous) cycle in which female animals are receptive to mating with males
Retina
A piece of neural tissue that contains the specialized photoreceptors & allows you to receive light info & turn it into a neural code
Endocasts
A plaster of the inside of the skull
Lateral inhibition
A process in which a cell's neighboring neurons inhibit the activation of that particular cell; refers to how the cells on either side of the cell that the light is hitting will be inhibited
Corona radiata
A projection of nerve fibers that connect the cerebral cortex to the brainstem & spinal cord
Dichromats
Have 2 types of cones
Traditional sensory neurons
Have receptive fields that only receive information from a specific sensory area Ex: visual neurons that are activated only when certain areas of the visual field are located
What is the purpose of an action potential being all-or-none?
Having the signal diminish wouldn't be good for information processing
What is pitch measured in?
Hertz (Hz)
How is nicotine delivery reinforcing?
High-affinity nicotinic receptors in the ventral tegmental leads to increased firing of dopaminergic neurons & the release of dopamine from the nucleus accumbens
What does the slow maturation of the brain (especially executive functioning areas) result in?
A protracted period of immature responses throughout the developmental stage of adolescence Ex: less likely to compute the long-term responses of risky behavior
What part of the brain do all vertebrate species have?
Hindbrain
Who proposed the existence of voltage-gated ion channels?
Hodgkins & Huxley after extensive work on giant squid nerve fibers
Axon caliber
How big the axon is; can affect how quickly signals are transmitted
Localization of brain function
How closely specific brain functions are mapped onto specific brain areas
What do central pattern generators explain?
How humans can walk while talking, reading texts, or chewing gum
Mechanoreceptor
A receptor in the skin that responds to touch or pressure; if they are disturbed through pressure (i.e. vibration, light touch, or deep touch) they will transduce a neural signal
Lens
A series of clear protein crystals that refract light
How is Tay-Sachs disease inherited? What occurs with this disease?
If 2 mutated copies of the recessive Tay-Sachs disease gene are inherited, the enzyme hexosaminidase A (Hex-A) will not be produced --> because it is important for breaking down lipids in the brain, lipid levels build up, destroying brain tissue & leading to death around 2 years old
Myelin sheath
A special insulating covering on many vertebrate axons that ensures the delivery of a consistently strong signal at a rapid rate; facilitates the speed of the neural impulse as it is propagated down the axon
Cerebellum
A structure primarily responsible for motor coordination; contains up to 80% of all the brains neurons
Basilar membrane
A structure that separates the scala tympani from the scala media & contains the hair cells on the apical (top) surface; moves in response to sound waves contains the hair cells
Phylogenetic tree
A type of diagram that represents the relationships among diverse biological species
What does chronic methamphetamine use lead to?
A type of toxicity characterized by decreased #s of dopaminergic (dopamine-sensitive) synaptic endings & decreased dopamine levels in the brain
What happened to the sensory systems as animals began to live in various habitats?
A vast array of sensory adaptations / specializations evolved Ex: honey bees can see UV light that humans cannot detect, male dogs can smell the social hormones excreted by a female dog 2 blocks away, dolphins rely on sounds to locate food in murky underwater environments
How many taste cells do we have in each taste bud?
About 100
How long does the refractory period last?
About 2 milliseconds (i.e. the length of the action potential process)
How many types of ganglion cells are there? Why?
About 20 - need a great variety of them to be able to see as well as we do because they are involved in many different specific functions (ex: fine examination, detecting motion)
How much of the body's energy does the brain consume?
About 20%
How many olfactory receptors do we have?
About 300 - allow us to discriminate millions of smells
What types of frequencies can place theory explain?
All of them, up to 20,000 Hz
Electromagnetic spectrum
All possible wavelengths of electromagnetic radiation
Specific association nuclei
Allow us to associate sensory & motor info for a certain region together so we can have a better way of responding to the stimulus
Round window
Allows fluids to move back & forth in the cochlea
Why is it important for the spine to have multiple segments (rather than 1 single bone)?
Allows us to move
What are some of the psychological effects of LSD?
Altered emotions, increased introspection, sense of being in a dreamlike state, unusual perceptions (hallucinations, illusions, alterations in perception of time / space, synesthesia)
Epigenome
Altered genetic material
Explain how myelination changes how the electrical signal moves
Alternate between slow action potentials in unmyelinated sections (i.e. the nodes of Ranvier) & fast graded potentials in myelinated sections
Electrolytic lesion
An electric current is used to damage the brain
"Gut feeling"
An emotional or body perception (indicated by physiological reactions like SCRs) that is being monitored by the brain's decision-making areas via the establishment of formidable neural networks
Anandamide
An endogenous substance that mimics cannabinoids
cGMP phosphodiesterase
An enzyme that reduces cGMP concentrations that maintain the open sodium channels
Explain the Phinneas Gage case
An explosion sent a tamping iron through his left cheek, brain, & skull, causing him to lost about 11% of his white matter, which drastically reduced his brain's ability to communicate --> specifically, the connections between the frontal lobes & both the limbic system + the basal ganglia were lost, resulting in behavioral changes (ex: became obstinate, impatient, fitful, etc.)
Flehman response
Animals, such as cats & horses, will roll back the upper lip so the VNO can access the chemicals / pheremones (ex: female's urine); allows the male to determine the reproductive status of the female
Which affects quality of life more: anosmia or agusia?
Anosmia
Progenitor cells
Another category of rapidly dividing cells; retain the ability of stem cells to eventually produce a specific type of cell but do NOT have the ability to produce pluripotent (unspecialized) cells because they are more specialized (i.e. can develop into various types of neural cells but can NOT differentiate into other types of cells, such as muscle or cardia cells)
Glial cells / glia / neuroglia
Another class of cells in the nervous system that support neurons & may also process information in a similar way as neurons; "nerve glue"
Indolamines
Another class of monoamines that includes serotonin
Retrosplenial cortex
Another cortical area implicated in context perception; gist-based contextual associations
Methodone
Another prescription opioid drug; used to treat opioid drug addiction because it engages with opioid receptors in a similar way BUT also decreases the euphoric response
Axon
Another specialized neuronal extension that carries nerve impulses away from the cell body
What do psychoactive drugs act as? Give some details on how this works
Antagonists or agonists for targeted neurochemical systems - can work during any stage of neurotransmission - may affect multiple neurotransmitters in different ways
Lateral geniculate nucleus (LGN)
Area in the thalamus that receives info about visual stimuli coming in from the eye
Where do synaptic vesicles cluster?
Around active zones on the presynaptic membrane
At what age does a decline in cognitive abilities begin?
As early as 30 years
Additive response
As the components become stronger (ex: unisensory auditory & visual cues), the level of exaggeration of the integrated neural response becomes smaller
Behavioral tests
Assess various behavioral phenotypes in animals (ex: learning, memory, stress, etc.)
Phase III clinical trial
Assesses safety & effectiveness of the drug in large human populations
Genotype
Assignment of alleles that are responsible for the expression of a particular phenotype
Bruce effect
Associated with a disruption of pregnancy when a female mouse is exposed to the scent of an unfamiliar male's urine
Dorsolateral prefrontal cortex (DLPFC)
Associated with perceptual integration & motor planning
In what way are perfected dance moves of the male blue manakin adaptive?
Associated with reproductive success
Nitric oxide
Associated with the brain's control of the cardiovascular system & learning
What are important emergency rescue cells?
Astrocytes
MPTP
Attacks the cells of the substantia nigra (a brain area that produces dopamine), producing a form of Parkinson's disease
Hydrophilic
Attracted to water
Molecular layer
Axons & dendrites
α motor neurons
Axons that enter the spinal cord via the ventral roots as they travel to the appropriate muscles
Cabled axons
Axons with similar destinations that are bundled together like a cable
Which type of receptors can GABA & glutamate act on?
BOTH ionotropic & metabotropic receptors
What are factored into Bayesian statistics to arrive at an optimal response choice? (2)
BOTH past experiences & current likelihoods
Rhombencephalon
Back portion of the developing nervous system; hindbrain
How do most cells know where they're born?
Based on the spatial & temporal cues Ex: a cell in the neural tube in the cerebral cortex will end up developing in the 1st layer because they're the only ones there, while the next cells to arrive will develop into the next layer of cells simply because of the space & timing that they were born into
What is the receptive area of the cochlea?
Basilar membrane
Why is it important that the eye keeps its spherical shape?
Because if the eye isn't in the correct shape, the light won't refract properly on the back
Why is knowing about the cranial nerves & whether they are sensory or motor or mixed important for functional neuroanatomy?
Because if you come in with facial paralysis one one side, for ex., a doctor might be able to isolate that to a nerve that primarily controls motor info, whereas if you come in able to move but cannot feel any sensation on one side, they might isolate it to a nerve that carries sensory info
Why do axons run in bundles?
Because it is more efficient
Why is it important that motor systems "come online" 1st before the sensory systems?
Because it is more important to be able to run away from danger
Why is the difference threshold / JND important?
Because it permits the measurement of subjective mental experiences in an objective way through altering stimuli
According to the opponent-process theory, why are opponent colors perceived?
Because of fatigue resulting from overstimulating the receptors for the opposing colors in the actual image
Why is biological psychology often called behavioral neuroscience?
Because of its focus on behavior
Why is neurogenesis research often done on rodent models?
Because scientists can systematically investigate rodent brains in ways they cannot investigate human brains
Why are there so many types of opioid receptors?
Because the brain contains a natural (endogenous) substance to which they had evolved to respond
Why is the corticospinal tract also called the pyramidal tract?
Because the cells where it originates in the cortex are pyramid-shaped
How does myelin affect the normal process of axon potential propagation?
Because the myelin is very tightly wrapped around the axon, it prevents the elaborate system of action potentials from working --> once the signal hits the myelin, the original action potential can NOT regenerate another action potential there
Why do the spinal nerves at the bottom have to travel far before they come off to innervate an area?
Because the nervous system stops growing by age 2 BUT people continue to grow height wise, which causes the spinal cord to pull up into the vertebral column as the body grows
Why does the action potential only propagate itself in one direction?
Because the preceding area is in a refractory area, the depolarization can NOT generate or propagate itself backward
Why is spinal cord damage especially an issue for myelin regeneration?
Because the spinal cord can stretch / separate & form scar tissue, which makes it even more difficult to do research on how to go down previously laid down myelin paths in order to connect them again
Why did Sperry do experiments on African clawed frogs?
Because their optic nerve can regenerate (which humans can NOT do)
Why is the resting membrane potential negative?
Because there are fewer positive particles inside the cell due to more of them being pumped outside of the cell than are being brought into the cell (NOT because there are more negative particles)
What is a potential problem with the eustachian tubes?
Because they go to the back of the throat, they can get inflamed, causing pain
Why do climbing fibers have a lot of control?
Because they synapsed very close to the cell bodies of the purkinje cells (rather than at the top), which means that climbing fibers have a lot of control due to temporal / spatial summation
How do we know that neurons are specialized cells?
Because we can use stains to visualize certain aspects of the cell
Off-center cells
Become inhibited when a light is focused on the center of a cell
On-center cells
Become stimulated when a light is focused on the center of the cell
What was so important about the Golgi stain?
Before the Golgi stain, researchers didn't really know about all of the projections coming off the soma because they could only see the cell body with the Nissl stain; showed us that there is a robust cell body with dendrites coming off it & that the axon looks different than dendrites
"Bystander stress"
Being housed with a rat that is experiencing a direct form of stress
What does layer V of the primary cortex contain?
Betz cells
What are some examples of how the skin can reveal many physiological clues? (4)
On a caucasian person: - using a tourniquet to trap blood somewhere makes the skin appear reddish - if blood is forced out of the hand, it appears yellowish - rich, oxygenated blood appears bluish or purple - deoxygenated veins make the skin appear greenish
What is the location of the somatosensory cortex in the parietal lobe?
On the post-central gyrus
B cells
Once a pathogen is recognized, they secrete antibodies into the bloodstream
How does cocaine work?
Once in the CNS, works by blocking the reuptake of dopamine, norepinephrine, & serotonin through binding to the proteins that act as transporters for neurotransmitter reuptake
How does the basal ganglia enable us to multitask?
Once motor memories are formed, we can perform a 2nd task Ex: can have a conversation while driving
Volley theory / cross-fiber theory
Once the frequency is high enough that an individual cell can not follow it, a committee / group of receptors begin to follow the frequency (i.e. input frequency = output of multiple receptors)
Climbing fibers
Only 1 climbing fiber goes to one purkinje cell (1:1 ratio) & synapses very close to the cell bodies of the purkinje cells; excitatory, use *asparate* as their neurotransmitter
What % of the neuron's total surface area does the soma account for?
Only about 4-10%
What type of transport system is the flow of ions (ex: chloride ions) through open ion channels in the membrane: passive or active?
Passive
What leads us to develop context frames?
Past experience
What does the medulla oblongata process on the top? On the bottom?
Processes sensory info on the top & motor info on the bottom
Top-down visual processing
Processing more integrated visual information based on context & expectations Ex: past experiences dictate our interpretation of a stimulus
Chemo affinity hypothesis
Proposal that neurons or their axons and dendrites are drawn toward a signaling chemical that indicates the correct pathway; factors screted by the superior colliculus / tectum create 2 gradients & the retinal cells, which have receptors on the ends of their axons, will grow towards the molecules that they have the correct receptors for
What does damage to the fusiform face area lead to?
Prosopagnosia
Histones
Proteins in the cellular nuclei; act as spools around which DNA coils
How are astrocytes involved in the blood-brain barrier?
Provide an additional security buffer to keep unwelcome substances in the blood stream & away from vulnerable brain tissue --> line all of the blood vessels & the surface of the brain to provide a barrier between the brain & the outside world
Pyramidal cell layer
Pyramidal cells
What happens once an action potential is set in motion?
Rapid depolarization occurs until the inside of the cell reaches a potential of close to +44 mV due to the opening of sodium ion channels in the cell membrane that allow Na+ ions to rapidly enter the cell (*sodium influx*)
What are 2 the most popular mammalian models? Why? (2)
Rats & mice because: - easy to house in the lab - have all the same brain areas & chemicals as humans
Restraint stress
Rats are confined in small tubes for a few hours
What is a study showing the importance of play?
Rats who are deprived of play & then subsequently given time to engage with another animal, they often compensate by spending even more time in play
Reflex arc
Receptor --> sensory neuron --> synapse on the dorsal root --> synapse on the ventral root with a motor neuron --> effector (muscle)
Where do odorant molecules bind to?
Receptors on the cilia of the sensory bipolar neurons
Single-unit/cell recording
Records the activity of individual neurons through micro-electrodes that are positioned in proximity to the neuron; has been used in studies with animals to determine specific neural responses associated with particular tasks
What is the brain's largest challenge?
Recovery from injury
What color is represented by the longer wavelengths?
Red
What is the most common type of colorblindness?
Red-green colorblindness
What happens to the hippocampus when an individual is experiencing depression?
Reduced functioning
What do studies show that domestication through selectively breeding animals in captivity does? How might this relate to humans?
Reduces brain size (ex: pet rats have brains that are 20% smaller than those of their wild counterparts) --> human brain size has also decreased by about 10% since 5000 years ago
Electrical gradient
Refers to how oppositely charged particles attract; to balance the unequal distribution of ions inside & outside of the axon, ions diffuse from an area of greater ionic density to an area of sparser ionic density
Neurogenesis
Refers to how the adult mammalian brain can create new neurons in certain brain areas
Allostatic overload
Refers to if stress continues for too long, the stress response system becomes more difficult to manage & wears down, leaving an individual at an increased risk for various diseases
Quanta
Refers to one vesicle release from a neuron, which is always an integer multiple; each time a specific neuron is stimulated, it typically releases the same # of packets Ex: if quantal release is 100 neurotransmitters per packet & the neuron always releases 4 packets, it will release 400 neurotransmitter molecules every time
Cerebral hemispheres
Refers to the 2 sides of the brain
Temporal summation
Refers to the additive affects of continual EPSPs (or IPSPs) so that the 2nd cell has a better chance of reaching threshold (or not reaching it); if you put once-scattered events together in succession, it will be a more powerful stimulus, even if it is the same amount of messages (i.e. timing matters)
Homeostasis
Refers to the body's tendency to preserve this constant internal environment (i.e. the homeostatic state)
Genetics
Refers to the branch of biology that pursues the study of heritable transmission & variability of inherited phenotypes
Nerves / peripheral nerves
Refers to the cabled axons extending beyond the CNS that travel to various sites in the PNS
Environmental context
Refers to the context provided by external & internal conditions; influences behavior & mental functions
Experiential context
Refers to the context provided by past or future experience; influences behavior & mental functions
"Tweaking"
Refers to the most dangerous stage of meth abuse, in which the user has reached the end of a binge & can no longer get satisfaction from the drug; users have engaged in dangerous behavior (ex: threatening & hurting loved ones, committing crimes)
Final common pathway
Refers to the pathway of the motor neurons in the ventral horn; these motor neurons must be activated to make a muscle move
Blind spot
Refers to the small section of the retina in which the optic nerve exits the back of the eyeball & there are NO photoreceptors, making it so an individual can NOT see any information that falls on this blind spot unless the information is coming from the other eye
Concentration gradient
Refers to the varying distribution of ions inside & outside the axon
What are some of the psychological effects of MDMA?
Same effects as amphetamine + increased sensory perception & a desire for social interaction
Umami
Savory taste; amino acid taste that is often found in MSG, which is sometimes added to food to make it taste better
Medial
Toward the center / midline
Rostral / anterior
Toward the front or mouth
Lateral
Toward the side
Caudal / posterior
Toward the tail or rear
Dorsal
Toward the top or back
What is a study showing the effects of enhanced NMDA receptor function (glutamate receptor)?
Transgenic (genetically engineered) mice with enhanced NMDA receptor function exhibit enhanced learning in an object recognition task, remember events longer, & solve complex mazes better
Spinothalamic (anterolateral) pathway
Transmits information from axons mediating tactile pain & temperature sensation in the skin; very similar pathway as the dorsal column-medial leminiscal pathway
How were lesions / the degeneration technique used to map the brain?
Saw which parts of the thalamus would degenerate when different pieces of the cortex were lesioned --> idea was that if there are areas in the thalamus that project to specific parts in the cerebral cortex, then this can be demonstrated by removing part of the cerebral cortex & then having the thalamic nuclei degenerate Ex: if they took one part out, the animal couldn't hear & if they took another part out, the animal couldn't move
Positron emission tomography (PET)
Scans convey real-time images of functioning in areas of the brain involved in various tasks; a substance like radioactive-labeled glucose is injected into the bloodstream & then carries over to the brain, where the PET scan can then display images of activity in the brain areas that are actively metabolizing glucose
What are some reasons that motor performance (ex: dance moves) are used as a selection method for male mates? (4)
Seem to be a valid assessment of the value of a male mate - reveals important information about the fitness of a male & suitability as a mate - impressive dancing conveys physical vigor - marker of overall organism health & performance potential
Vestibulocochlear nerve / auditory nerve
Sensory; hearing & balance in the inner ear
Olfactory nerve
Sensory; smell in the nose --> this info is brought to the telencephalon
Optic nerve
Sensory; vision in the eye --> this info is brought to the diencephalon
Cell membrane
Separates internal & external cellular environment
Explain how glomeruli work in the olfactory system
Several thousand sensory neurons synapse on just 1 kind of glomeruli as a result of a sorting so all of one odorant goes to a particular glomerulus --> this allows for a simplification / extraction of features
What were the results of Bartholow's study on Mary Rafferty?
She was unable to override the electrical impulse in her brain that caused her to move, even when Bartholow asked her to try & do so
What is the efficiency of the autonomic nervous system critical for?
Short- & long-term survival of animals
Proximal causes
Short-term causes of behavior Ex: hormonal secretions, unexpected loud noise
Interneurons / microneurons
Small neurons that stay in their brain structure & make local connections
Electrode
Small piece of medal that is insulated everywhere except for the tip that can pass electrical current through it
Dendritic spines
Small protrusions located throughout the dendritic processes that provide additional surface area
Microglia
Smaller glial cells; sometimes considered the brain's "first responder cells" or "scavenger cells"
Rigid paralysis
So tense that muscles can NOT move
What was the explanation for the study examining the effect of social context on neurogenesis due to running among rats?
Social contact may have reduced the rats' stress levels & accompanying levels of toxic stress hormones --> certain conditions therefore may determine whether the demands of running are stressful or healthful
What do athletes rely on the basal ganglia to execute?
Solidified motor memories ("muscle memories") that have been consolidated throughout years of practice (because once these movement memories are formed, they are resistant to interference & can be retrieved after long periods of time without training)
Explain the general somatosensory pathway
Somatosensory axons travel from the skin to the CNS by way of the dorsal root ganglia in the spinal nerves
How does the axon know where to go?
Space + time AND mechanisms that the cells are looking for a cue to follow
What types of summation are at play during the time concept idea for sound localization? (2)
Spatial & temporal summation
The fovea has very high __________ ______________. Why?
Spatial resolution - helps you see details
What is some evidence of the involvement of serotonin 2A (5-HT2A) receptors in psychiatric illness?
Study found increased #s of these receptors in the prefrontal cortex & hippocampus BUT NOT in the nucleus accumbens of teenage suicide victims
What is a study showing the effects of impoverished environments on humans?
Study found that people who died in a nursing home had smaller brains than those who were the same age but died in some other location
What is a study showing how the primary motor cortex is involved in a motor task performance?
Study found that rats trained in a motor task performance exhibit *increased synaptic complexity in the primary motor cortex* & a *modified cortical map representation* accompanying more precise performance in motor skills
What is a study showing the importance of facial skin color in judging people's health?
Study found that when asked to adjust an image of someone's face to make them appear healthier, subjects responded by making the face redder, which is consistent with increased oxygenated blood flow
What is a study showing that blind individuals have similar mirror neuron networks to sighted individuals?
Study suggested that sighted & congenitally blind subjects showed similar patterns of fMRI brain activation when they were exposed to auditory presentations of hand-executed actions (ex: the sound of scissors) & when they pantomimed that action via manipulation of a virtual tool
What must happen to make a complex cell fire?
The body must ensure that all of the simple cell signals reach the complex cell at the same time because if this doesn't happen, the complex cell will NOT fire because it isn't summative
Endocrine system
The body's hormonal system
Contralateral
The brain & the body are on the opposite side (i.e. most motor & sensory information that is in the left visual world is processed on the right side of the brain & movement is controlled by the opposite side of the brain)
Ipsilateral
The brain & the body are on the same side
What is the cost of the vertebrate nervous system, as it has evolved?
The brain must be protected to ensure survival
Cerebral cortex
The brain's outer layer
Papillae
The bumps that contain taste receptors
What happens without glucose & oxygen provided by blood flow?
The cell enters a phase of ionic flux
Ventricular system
The central canal, 2 lateral ventricles (1 on each side), the 3rd & 4th ventricles, & the cerebral aqueduct
What was incorrectly believed to contain the majority of the brain's neurons?
The cerebral cortex (BUT in reality, it only contains 19%)
Skin theory of color vision
The colors emphasized in our visual repertoires allow us to see changes in skin color that provide information about a peer's health or emotional status
Addiction
The compulsive dependence on a behavior or substance
What do you need to know to calculate the Nernst equation?
The concentrations of the ion inside & outside the cell
Bregma
The connection point between the coronal & saggittal sutures (seams) in the skull
Transduction
The conversion of physical energy to neural energy
What focuses the image so it is projected to the retina at the back of the eye?
The cornea & the lens
Explain the difference between the Nissl stain & the Golgi stain on a double stain image
The dark colors are the Golgi stain & the red/pink colors are the Nissl stain
What happens to motor information after it reaches the frontopolar cortex?
The decision gets fed back through all of the systems to the primary motor cortex
Nigrostriatal pathway
The dopamingergic tract / pathway from the substantia nigra to the striatum
What part of the spinal cord contains axons?
The edges of the spinal cord
Oval window
The entry point for the sound into the cochlea
What was the result of Bartholow's study on Mary Rafferty, in terms of ethics?
The experiment was deemed unethical because Mary Rafferty died a few days after the experiments --> the AMA banned any kind of human experimentation that disregards saving the patient's life
Cognitive neuroscience
The exploration of brain functions that accompany various cognitive functions (ex: perception, language, memory)
Cochlear nucleus
The first brain stem nucleus at which afferent auditory nerve fibers synapse; spans the border of the brainstem & the pons
Broadman's area #17
The first place in the visual cortex that receives visual information
Frequency modulation (FM)
The frequency of the sound wave is varied
Neuron
The fundamental unit of the nervous system; nerve cell
Explain why an insect can still live with its head cut off
The ganglia (cell bodies outside of the CNS that are distributed throughout every body segment) can still perform basic nervous functions responsible for reflexes
Explain the distribution of white & gray matter in the cerebellum
The gray matter (cell bodies) are on the outside & the white matter (myelinated axons) are on the inside (SO it is the opposite set-up as the spinal cord organization)
What happens at 100 days, in terms of prenatal brain development?
The gross structure closely resembles the adult brain, except for the smaller size & smooth cortex
Dendritic aborization
The growth of dendritic processes; becomes more complex as a child experiences the world
Why have TBIs become much more common?
The human brain will likely never generate adequate mechanisms to compensate for human's desire to propel themselves at speeds our ancestors never imagined
Time concept (sound localization)
The idea that sound waves hit the closest ear first, which then starts to report information milliseconds before the other ear; we have a circuit in our brainstem auditory nuclei that allow us to detect & measure these small differences & that only fires if a stimulus comes in at different times
Nerve net theory
The idea that the nervous system consists of a continuous network of connected nerves
How does the neural groove form?
The neural plate starts to sink down & invaginate; then the cells on either side come up over it, resulting in a neural groove (the sunken down invagination)
What does the neural groove become?
The neural tube
Enzymatic deactivation
The neurotransmitter is broken down by enzymes that are specific to the neurotransmitter Ex: acetylcholinesterase breaks down ACh in the synapse
Reuptake
The neurotransmitter is transported back to the presynaptic neuron & repackaged for reuse
Neuron doctrine
The notion that neurons are discrete units (NOT part of a continuous network); central tenet of modern neuroscience
How do the number of muscle spindle organs & golgi tendon organs vary?
The number of them varies in different muscles Ex: more muscle spindles & golgi tendon organs in a muscle / tendon that is in an area involved in fine motor control
Why is Brodmann's number labeling system not very useful, in a practical sense?
The numbers are very jumbled & NOT in any particular order SO they aren't the most helpful to keep track of things
Where are the oldest cells in the 6-layered structures in the cerebral cortex? Where are the youngest cells?
The oldest cells are in the ventricles --> sub-ventricular zone (SVZ); the youngest cells are in the top layer
Conduction deafness
The ossicles don't work SO cannot conduct sounds from the eardrum to the oval window; also, can be caused by the eustachian tubes getting infected & leading to degeneration of the bones
Dura mater
The outer layer of the meninges that lies just beneath the skull; works with the skull & vertebral column to provide another layer of protection for the CNS
Temporal hemiretina
The outside half of the retina; located by the temples on the eyes on either side
What is an exception to the idea that some animals (including humans) evolved to become diurnal & therefore needed more accurate visual assessments of their environment (through having additional cones)?
The owl monkey --> switched from being diurnal to nocturnal; have large eyes that allow more light to enter the eye to enhance visibility during darkness
Fovea
The part of the retina where our vision is the sharpest because it contains a large amount of cones; the region in the middle of the retina that is in the center of the visual field
Corticospinal tracts
The path that axons travel from the cerebral cortex to the spinal cord; essential for voluntary movement
Audition / hearing
The perception of sound produced by variations in sound waves
Photopsin
The photopigment in cones
Rhodopsin
The photopigment in rods
Pyramidal decussation
The point where axon tracts (pyramidal tracts) from one side of the body cross to the other side of the body; arbitrary place where the spinal cord ends & the brain begins
Synaptic transmission
The process by which a neuron communicates with another neuron or neurons across a synpase
Pharmocokinetics
The process by which the drug is absorbed, distributed, metabolized, & eliminated by the body (i.e. what the body does to the drug)
Phagocytosis
The process in which innate immune system cells (phagocytes & macrophages) indiscriminately engulf & digest pathogens
Endocytosis
The process of bringing something back into the cell; reuptake transporters on the presynaptic cell are responsible for this
Axon shearing
The process of damage occurring as axons twist & tear
Gliogenesis
The production of glial cells
Neurotrophic factors
The proteins & other substances that influence various neuroplasticity functions; essential for the development of a healthy brain
What is saturation determined by?
The purity of the light stimulus, represented by the precision of the wavelength bandwidth of the visual output
What allow for contralateral movement / info?
The pyramidal decussation
What explains the fact that when you stimulate one of the motor cortices, the other side of the body moves?
The pyramidal decussation & crossing over of motor information
What is the result of having a very high density of photoreceptor cells in the fovea?
The receptive fields are must more sensitive, in that they are activated more readily by smaller amounts of light --> each cell is responsible for a very small & specific part of the receptive field (unlike in the rest of the retina where each one is responsible for a larger area)
Ventral posterior nucleus of the thalamus
The relay nucleus of the thalamus specialized for somatosensation
Neuromuscular junction
The synapse formed when the axon terminal of a motor neuron positions itself in a section of the extrafusal muscle fiber called the motor end plate; cholinergic synapse (i.e. uses ACh)
Therapeutic effects
The targeted & beneficial consequences of a medical procedure Ex: reduction in a patient's depression symptoms
Synapse
The tiny space (about 10 nanometers) between the 2 neurons; refers to the pre-synaptic & post-synaptic events, & the space
Explain the spinal nerves at the top of the spine vs. those at the bottom
The top spinal nerves come off very squarely because they innervate the areas right beside them, while the spinal nerves at the bottom have to travel down pretty far before they come off (i.e. are very stretched out)
Adequate stimulus
The type of physical energy that these receptors respond to effectively
Magnocellular layers
The ventral layers of the LGN that are characterized by larger cells; provide information about the position of the visual stimulus (i.e. "where")
Extrastriate cortex
The visual cortex located outside of the primary visual cortex (V1) / striate cortex
Visual field
The visual information that we process at a given time
Opponent-process theory of color vision
The visual system is designed to detect opposed pairs of colors, specifically green vs. red, blue vs. yellow, & black vs. white
What happens when eotaxin is injected into young mice? What does this suggest?
The young mice take on older characteristics by exhibiting decreased performance on cognitive tasks & rates of neurogenesis --> suggests that eotaxin is associated with the cognitive decline of aging
Compare the number of neurons at birth (specifically, embryonic day 11) vs. as an adult
There are 2x as many neurons at birth than there are in an adult
What happens to telomeres over time? What does this result in?
They get worn down & lose their ability to function --> this results in increased cell death & age-related cognitive decline
What has been the positive result of neuroimaging techniques?
They have been valuable in understanding localization of function --> brain functions may not really be all that localized
What is the effect of psychostimulants such as amphetamine & methylphenidate (Ritalin) on play duration?
They reduce play duration
What caused the 6 individuals to become "frozen" as if they had Parkinson's disease?
They thought they were taking heroin, but it actually was an analogue of the narcotic medicine Demerol (meperdine), which is a toxic substance
Does nicotine really produce a calming effect?
This calming effect might just be a result of the individual's history of smoking --> a study showed that nonsmokers who received a nicotine injection, patch, or gum reported feelings of increased tension & arousal
Where do nerves in the sympathetic nervous system extend from?
Thoracic & lumbar areas of the spinal cord
Somatic functions
Those that are under our voluntary control (ex: walking, reaching)
Generalized seizures
Those that originate from larger areas dispersed across both hemispheres
Partial seizures
Those that originate in a localized brain area
What is a functional difference between subjects who have consumed alcohol & those who have not, on a PET scan?
Those who had consumed alcohol showed less activity because alcohol slows down neural functioning
What did Darwin speculate might be the mechanism of heredity?
Thought that heredity was transmitted in the blood
How can you assess the efficacy of a drug?
Through a controlled study involving a placebo
How were the 3 types of cones discovered?
Through behavioral experiments in the field of psychophysics in which they did sensory tests on people by showing them a color to see if they could see it, for example
Where does eye enter the eye?
Through the pupil
Cilia
Tiny hair growths located on the hair cells
What is the goal of studies that are assessing the efficacy of a drug?
To avoid the placebo effect
What is the goal of creating a lesion?
To determine the effect of losing specific brain areas on a particular behavior --> if the animals with a brain lesion behave differently than control animals with a sham lesion, then the targeted brain area is thought to be associated with that behavior
What can glial fibrillary acid protein be used for?
To determine whether cells will mature into glial cells
What are some of the major goals of neuropsychopharmacological research? (3)
To develop drugs that have: - an *affinity* for the targeted neurotransmitters' natural tendencies in the brain - a high *efficacy* - *potency*
Why are animal models used?
To investigate certain biopsychological questions in a controlled lab setting
What is the function of the vitreous humor & the aqueous humor, collectively?
To maintain a healthy internal environment than the eye
What is the purpose of optimal actions?
To optimize survival, including behaviors associated with reproduction., health, & regulation of movement during stressful times
Where are taste receptors ("taste buds") located?
Tongue, roof of mouth, back of the throat, top of the esophagus (i.e. NOT just the tongue)
What type of organization does the cochlear nucleus have?
Tonotopic organization
Phantom leg syndrome
If a limb is amputated, you might still have "sensation" in this area (even though the limb is NOT there)
What is the significance of the cilia being linked together by tip links?
If one cilia is displaced, they ALL will be displaced
Explain how the effect of serotonin on play depends on the relationship between 2 rat playmates?
If one rat is more dominant, a reduction in serotonin levels increases the # of pins in a wrestling bout
What is a downside of habits?
If our brains rely on too many habitual responses, they begin to give up on valuable real-time processing of the environment
McGurk effect
If slightly mismatched auditory & visual cues are paired, people report hearing something more consistent with their visual input
What makes it so the Bruce effect does NOT occur?
If the female mouse's VNO is lesioned
Where is the gustatory cortex located?
In an area of the parietal lobe that is very close to the face area of the somatosensory cortex
When does the phase difference idea of sound localization work?
In an ongoing way (NOT just at the initiation of the sound)
Where are axon diameters the largest? Why?
In axons regulating the more essential life functions because this allows for faster conduction velocity
Where does CSF exist?
In the 4 ventricles
Where do voltage gated Na+ channels cluster?
In the nodes of Ranvier to promote saltatory conduction
Where do olfactory sensory neurons synapse?
In the olfactory bulbs
Where are the most stem cells located for adults?
In the olfactory system
Where are seizures theorized to start?
In the place where the aura is located Ex: if you have a seizure that begins with a smell-related aura, then that probably is the localization of the abnormality in the brain
Epinephrine (adrenaline)
In times of acute stress, plays a similar role to norepinephrine in the sympathetic nervous system
Anosmia
Inability to smell
Agusia
Inability to taste
Animal care & use committee
Includes university members, community members, veterinarians, etc.; the purpose is to ensure that the research is for the greater good of humanity & that the animal is not in any pain or discomfort that cannot otherwise be accounted for
What is a biological explanation for the fact that adolescents are more likely to engage in risky behaviors?
Incongruent maturation of the PFC & limbic areas such as the nucleus accumbens involved in reward, which is followed by an increase in dopamine activity, contribute to a developmental phase of disproportionately high risk-taking behavior during adolescence that levels off during adulthood
What was the mechanism by which the high-licking mothers altered their pups' genes?
Increased maternal attention modified genetic material at a specific glucocorticoid receptor gene promoter by altering DNA methylation
In what way are superstitious behaviors adaptive in the animal kingdom?
Increases animals' attention toward cause & effect (contingencies) in their environment
Associative sequence learning model
Indicates how mirror neurons & their circuits may be formed during infant development; as infants see their parents' faces & imitate their parents' expressions simultaneously, their sensory & motor neurons are activated simultaneously, & over time, stronger connections form between the sensory & motor neurons so that the neurons in the mirror neuron circuit are activated by neuronal input from multiple sensory & motor areas
What visual features are processed by magnocellular fields?
Information about movement & more general visual patterns ("where information")
What visual features are processed by parvocellular neurons?
Information about visual details, including color ("what" information)
Premotor cortex
Located ventral to the supplementary motor complex, directly in front of the primary motor cortex
Pre-frontal lobe / frontopolar cortex
Location of judgement, attention, reasoning, personality, etc.; decision area that decides whether you should move by putting together motor inputs with inputs from the parietal lobe, occipital lobe, etc.
Pyramidal decussation
Location of the crossing over of information; dividing point between where the spinal cord stops & the brain begins
Neural crest
Looks like a line going down the longitudinal axis of the embryo; located where the backbone will be
Hyperpolarization
Making the resting membrane potential more negative; when the cell overshoots (i.e. becomes even more negative than the resting potential) due to potassium eflux when the voltage-gated K+ channels open
Who has more apacrine glands: males or females?
Males
Conspecific males
Males of the same species
Heroin
Manufactured in the 19th century from morphine by adding 2 acetyl groups to the morphine molecule; when taken orally, has similar effects as morphine BUT when injected, it is much more potent because it basses into the brain more easily & is converted into morphine
Conservative process
Many more similarities than differences exist among the brains of various species, which indicates that principles have been conserved
Epigenetics
Modified gene activity that is transmitted to subsequent genes, as apposed to the more permanently ingrained genetic code; the interaction between genetics & the environment
What is the function of the subcortical systems?
Modulate complex information processing
Photopigments
Molecules consisting of *opsin* (a specific type of protein) & *retinal* (made up of fatty substances such as lipids)
Odorant molecules
Molecules that we can smell
Autonomic functions
Moment-by-moment life-sustaining functions of our internal organs; typically considered involuntary
How does MDMA work?
Monomine agonist that leads to the release of stored serotonin & dopamine
What is the major function of rods?
More active in dimly lit environments because they are more sensitive to light
In primates only, what does a larger brain indicate?
More neurons Ex: across primate brains, humans have the largest brain size (both absolute & relative) with the largest # of neurons
What does the growth of cortical association areas allow for?
More opportunities for integrative analysis of environmental surroundings & therefore more advanced cognition because decisions to engage in certain responses could be influenced by multiple factors
Is the human hand more or less sensitive than raccoons? Why?
More sensitive - because raccoons lack the sensitive Meissner's corpuscles
What happens at 6 weeks, in terms of prenatal brain development?
More specific brain areas (ex: hippocampus, cerebellum) begin to appear
What happens if there are more membranes in the outer segment of a rod or cone?
More surface area for the photopigments, which makes the cell more sensitive to light
Explain many antidepressant drugs in terms of affinity & efficacy
Most antidepressant drugs have a high affinity for blocking serotonin reuptake BUT have low efficacy
Glutamate
Most common excitatory neurotransmitter in the CNS; involved in brain plasticity mechanisms (such as synaptogenesis as neural networks are formed) & in strengthening existing synapses to facilitate learning & memory
Ventral horn
Motor info (efferent info) goes out through this section of the spinal cord
Efferent nerves
Motor nerves that allow for movement; allows motor info out into the environment
Trochlear nerve
Motor; eye muscle (superior oblique)
Oculomotor nerve
Motor; eye muscles
Abducens nerve
Motor; eye muscles (external rectus muscle)
Facial nerve
Motor; face muscles
What is a core component of a majority of responses in our behavioral repertoire?
Movement
What does exercise focus on?
Movement repetition, intensity, & duration
Optimal actions
Movements / actions that minimize costs & maximize benefits
How are complex cells structured?
Multiple simple cells connect to 1 complex cell
What is the most common shape of the neuron in the nervous system?
Multipolar neuron
What represents the most relevant perceptual experiences of animals, including humans?
Multisensory integration
Extrafusal fibers
Muscle cells that contract to shortern a muscle
Intrafusal fibers
Muscle cells that detect changes in muscle length
All movements require _____________ ______________
Muscle contraction
Ciliary process
Muscles that allow the lens to change its shape so you can see things that are close or far away; holds the lens in place
Antagonistic muscles
Muscles that produce actions that are opposite of one another (ex: biceps & triceps)
Explain the dance of the male blue manakin
Must dance in a duel with another bird to win the sexual attention of a female
White matter
Myelinated axons
When does myelination typically begin? How long does it last?
Myelination typically kicks in around the 3rd trimester & then continues through the 3rd decade of life
How does the glutamate system adapt to chronic alcohol use? What might this explain?
NDMA glutamate receptors increase their numbers in the cerebral cortex & the hippocampus, & glutamate release increases in the striatum --> may be related to the hyperexcitability & irritability that people experience during alcohol withdrawal
What is the total voltage of the cell determined by?
NOT any 1 incoming signal but rather by the overall pattern of all the inputs received all over the cell (both excitatory & inhibitory) --> if excitatory > inhibitory, then the cell voltage may reach the threshold for an action potential
What are some disadvantages of TMS?
NOT as specific as fMRI or PET on spatial resolution or pinpointing exact functional areas of the brain
What is the benefit of spatial summation?
NOT limited by how fast an action potential can be generated
What does the Nernst equation predict the resting voltage for sodium (Na+) is, if it was a freely moving ion?
Na+ = +57 mV --> when an action potential occurs & sodium ions are able to move freely, the membrane potential reaches right around this charge
In what way is myelin a resource saver?
Need lots of resources (ex: sodium channels, potassium channels, sodium-potassium pumps, etc.) to have a section of axon that can have an action potential BUT you do NOT need these things as much where the myelin is because they are not needed to propagate the action potential --> therefore, the cell can concentrate action potential resources in the unmyelinated sections & allow the myelin to do fast signal propagation through graded potentials
In what way does myelin cost resources?
Need to produce the oligodendrocytes (or Schwann cells) to build the myelin, which takes more types of cells
Resting membrane potential
Negative polarity of the resting membrane; typically is about -50 to -80 millivolts, as measured by cellular recordings
Double-blind studies
Neither the patients nor the researchers know the group assignments
Neurotrophic factors
Nerve growth factors
What work to produce behavioral & physiological changes?
Neural circuits
Endocannabinoids
Neuroactive lipids produced by the body itself that mimic the psychology effects of the cannabis plant; most notable example of a lipid-derived transmitter substance; involved in a variety of psychological processes (appetite, pain sensation, mood, memory, motor learning)
What is the knee jerk test assessing?
Neurological test to determine the efficiency of the *monosynaptic spinal reflex*
Which ACh receptor is ionotropic?
Nicotine (nicotinic)
Are the eustachian tubes directly involved in hearing?
No
Do humans have the largest cerebral cortex?
No
Does any degeneration ever happen to the non-specific nuclei when different parts of the cerebral cortex are lesioned?
No
Do the voltage-gated Na+ channels stay open while the voltage-gated K+ channels are open?
No - because the cell is not at a voltage that allows the voltage-gated Na+ channels to stay open
Does the "super-sensitivity" of raccoons' forepaws extend to the hind paws? Why or why not?
No - because the forepaw skin has 4x more sensory receptors than the hind paw skin
Can a vesicle release 1/2 of its contents?
No - can NOT have anything less than an all-or-none vesicle release
Are gaseous transmitters stored in synaptic vesicles?
No - can readily pass through the cell membrane
Do photons of light drive the visual system?
No - complex features drive it
Is it possible to be completely in the absence of sound?
No - even if you put people in a 0 dB sound proof chamber, they will eventually begin to hear their own sounds (ex: heart beating, air molecules hitting the ear drum)
Is excitation more important than inhibition?
No - inhibition is just as useful of a tool for the nervous system as excitation
Is neurochemical transmission the only mode of neuronal communication?
No - some electrical synapses do exist (though neurochemical transmission is the most prevalent mode)
Is there any place in the brain that you can have damage that causes complete loss of hearing in one hear? What are a few exceptions? (3)
No - the exceptions are the cochlea, 8th cranial nerve, & cochlear nucleus, in which damage can cause loss of hearing in one ear
Are muscles directly attached to bones?
No - they are attached to tendons, which are directly attached to the bone
Are cortical neurons born in the cortex?
No - they are generated in proliferative areas & then must migrate to their final cortical destinations
Are decibels / loudness linear or additive?
No - they are logarithmic Ex: if there was a TV playing at 60 dB & then you added another TV, the combined dB might be 64 dB (NOT 120 dB)
What is Huntington's disease characterized by?
Uncontrollable movement due to cell loss in the caudate / putamen, which makes patients lose the ability to inhibit the inhibitor
Seizure
Uncontrollable neural activity that is electrical; characterized by synchronous brain activity on an EEG (unlike normal brain activity, which is asynchronous)
Choreas
Uncontrollable, dance-like movements; begin as spastic head or arm movements but then quickly progress to having writhing movements that make it difficult to do everyday activities, in the case of Huntington's disease
What type of control are cardiac muscle & smooth muscle generally said to be under? What recent research suggests that this might not be entirely true?
Under involuntary control BUT research on *biofeedback* suggests that people can be trained to control physiological responses that are typically viewed as involuntary (ex: blood pressure, relaxation of the internal anal sphincter)
Computed tomography (CT)
Uses x-rays & computer technology to provide horizontal (2D) images of the brain; x-ray beam moves around the head showing different views of the head, which are then interpreted & displayed by a computer
What does the presence of a methyl group at a gene promotor do?
Usually prevents expression of that gene
Can you lose myelination once you gain it?
Usually you do NOT lose it for the rest of your life (unless there is an issue)
Orientation columns
V1 neurons that respond to lines of a particular orientation are grouped together in these specific orientation columns
Confounding variables
Variables other than the IV of interest that may affect the DV
Alleles
Varying versions of genes
What types of neurons/nerves do NOT easily regenerate? Why? (3)
Vertebrate CNS neurons - lack of immune-system cells - the presence of inhibitory proteins - migration of astrocytes to the threatened site can leave scar tissue on the damaged axon
Dendrites
Very complex, branchlike parts of a neuron that extend outward from multiple points on the soma & are specialized to receive information
Reflexes
Very fast neural networks that are outside of the domain of the brain's cortex
Where is the olfactory bulb located?
Very front of the brain under the temporal lobe
What types of frequencies can frequency theory explain?
Very low frequencies, up to about 200 Hz
According to the trichromatic theory of color vision, what happens when all colored lights are superimposed?
Viewers see white (which is different than what happens when you mix different paint colors)
Rods & cones
Visual photoreceptors that line the most peripheral layer of the retina
What is the Nernst equation?
Voltage (V) = +/- 60 Log (ion concentration outside / ion concentration inside) *positive or negative 60 depending on whether the ion you are looking at is positive or negative
What does activation of specific areas of the motor cortex accompany?
Voluntary control of corresponding muscle groups in the body
Skeletal (striatal) muscle
Voluntary muscles; connected to bones & allows us to move our body / limbs
Aqueous humor
Watery; occupies the space between the cornea & the lens
What can lead to athletes "choking" under pressure?
When athletes who have achieved high-level automaticity step back to think about the individual moves (thus involving the pre-frontal cortex), they introduce error into the highly trained movement machine
Potassium eflux
When potassium rushes out of the cell once the voltage-gated K+ channels open during an action potential; this causes the cell to become more negative (i.e. lose positivity)
How does ATP release energy?
When the bond between the 2nd and 3rd phosphate bond is broken to form adenosine diphosphate (ADP), this energy is used to transfer 3 Na+ out & 2 K+ in
What was the key question in Sperry's study?
When the optic nerve axons grow back, will they go straight back to where they used to be (because they intrinsically know where to go) OR will they grow to the place that they are in visual space (because they are getting cues to help them find their place)?
What are some treatments for epilepsy (NOT cures)? (3)
- *drugs that increase levels of γ-aminobutyric acid in the synapses*, which suppresses neuronal excitation & increases neuronal inhibition - *severing the corpus callosum* to prevent the seizure from spreading across hemispheres - *surgically removing the affected brain area or the entire hemisphere* (hemispherectomy)
What are some different types of mechanoreceptors? (3)
- Meissner's corpuscles - Pacinian corpuscles - free nerve endings
What color pairs do afterimages come in? (2)
- red vs. green - blue vs. yellow
What are 3 diseases of the synapses?
1) myasthenia gravis 2) Parkinson's disease 3) Huntington's disease
What are the original 3 large sections of the developing brain?
1) proencephalon 2) mesencephalon 3) rhombencephalon
On a molecular level, what 4 major processes are needed for brain development?
1) proliferation 2) migration 3) differentiation 4) apoptosis
What are 3 main cell types with the cerebellar circuitry?
1) purkinje cells 2) mossy fibers 3) climbing fibers
What are 3 types of colorblindness?
1) red-green colorblindness 2) blue-yellow colorblindness 3) complete colorblindness
What are the 2 types of photoreceptors?
1) rods 2) cones
What is the pain threshold, in terms of decibels?
120 dB
Horizontal cells & amacrine cells
2 other types of specialized cells that facilitate the integration of the vast amount of information processed in the retina to create a uniform image; facilitate or inhibit communication between photoreceptors and ganglion cells to adjust the image sent to brain
Bisynaptic
2 synapses
Subsonic
20 Hz
How much of our total energy does our brain consume?
20%
What is the limit to how many times per second an action potential can be generated?
200 times per second
What do animal models suggest in regards to seizures?
Seizures set a chain of events into motion that lead to altered gene expression in the brain & subsequent modifications of excitatory neural networks by increased activation of brain growth factors (ex: brain-derived neurotrophic factor)
How do selective serotonin reuptake inhibitors (SSRIs) work?
Selectively inhibit the reuptake transporter, thus allowing serotonin to stay in the synaptic cleft & continually stimulate the postsynaptic cell
Cell membrane is _____________
Semipermeable / selectively permeable
Meissner's corpuscles
Sensitive to light & touch; concentrated in sensitive skin areas (ex: lips, fingers)
What is a large proportion of the cortex dedicated to in the platypus?
Sensory functions of the bill
Dorsal horn
Sensory info (afferent info) comes in through this section of the spinal cord
What is our body's largest organ?
Skin
What are some of the side effects & long-term effects of MDMA?
Sleep disruptions, depression, anxiety, cognitive deficits, involuntary teeth clenching, temperature dysregulation, cardiovascular effects, kidney injury, liver disease
Cochlear implants
Small electronic device that can be used to restore some aspects of sound perception in many deaf individuals with impaired cochlear function
Antibodies
Specialized chemical missiles that travel to the infected area to tag infected cells for T cells to destroy
FM-FM neurons
Specialized delay-tuned neurons that respond to the delay between the FM component of the signal sent by the bat & a higher FM component of the returning auditory signal
Sodium-potassium pump
Specialized membrane protein channels that transport 3 Na+ ions out of the cell for every 2 K+ ions that they transport into the cell, thus providing a net exit of positive Na+ ions to the extracellular space; a type of ion pump that plays an important role in maintaining the unequal distribution of Na+ ions & K+ ions across the membrane (i.e. more Na+ ions outside the cell & more K+ ions on the inside of the cell)
Photoreceptors
Specialized neurons that are sensitive to light
Theory of natural selection
Species that are uniquely adapted to their environment (i.e. the physical *context* of their habitats) tend to have higher survival rates than species that are not
Amine group
Specific class of organic compounds
Explain the path of tactile information arriving at various areas in the body
Spinal nerve in the dermatome --> ventral posterior nucleus --> primary somatosensory cortex, secondary somatosensory cortex, etc. All of this occurs via the dorsal column-medial leminiscus pathway
How did Gazzinga & Sperry's studies with split-brain patients work?
Split-brain patients & healthy, age-matched subjects were asked to carry out a particular task in response to a stimulus presented briefly to either the left or right visual field
Golgi stain
Stains the entirety of the neurons (NOT just the cell body, like with the Nissl stain); only about 1-5% of the neurons take up the stain
External granular layer
Stellate cells & small pyramidal cells
John Flynn
Stimulated different areas in the hypothalamus of cats to test his hypothesis that it was involved in behavior
Cross-modal stimuli
Stimuli from 2 senses
Gregor Mendel
Studied that pea plant to understand the unit of inheritance --> would breed different varieties of the plant with one another & record the resulting phenotype
Can we detect pheremones?
Studies have found that before puberty, children can detect these odors BUT after puberty, 50% of people claim that they can no longer detect them (15% of which find them very offensive & 30% of which are extremely sensitive to them)
Anterograde dye
Takes things going forward (i.e. normal neuronal processing) & can trace from a location to where that that neuron is projecting to; whatever cell bodies it is injected into, it will move the dye down using the cytoskeleton & give it to the end of where the synapses are
What types of summation are involved in whether a complex cell fires?
Temporal & spatial summation
Where is the hippocampus located?
Temporal lobe, primarily on the lateral side
What type of summation is involved in whether a simple cell fires?
Temporal summation
Affinity
Tendency for close binding
Cable conduction
The action potential at 1 location of the membrane stimulates the next location to produce a new action potential, which continues down the entire axon membrane
What do the olfactory bulbs contain?
Olfactory glomeruli
What are the largest # of genes that we have for?
Olfactory receptor cells
Golgi apparatus
Packages proteins within the cell before they are sent to their destination
What is one exception to the rule of sensory adaptation? Why?
Pain - because it relays an important biological message relevant to one's health
Bayesian decision theory
A possible explanation of how the nervous system selects optimal actions for movement in an uncertain world; involves applying probabilistic reasoning to make inferences based on uncertain circumstances
Electrical synapses
Characterized by the alignment of 2 neurons so that connexons (specific channels) align perfectly for form a gap junction where electrical currents can be exchanged between the 2 cells
Ions
Charged molecules
Visual acuity
Clearness of vision
Proximal
Closer to the CNS
Nuclei
Cluster of neurons; distinct groups of similarly functioning neuronal cell bodies
How does opium work?
Opioid receptors throughout the brain
How are the neurons in the primary motor cortex involved in the transformation of an athlete from novice to expert?
Orchestrate movements toward a consistent goal or intended outcome of movement
Tonotopic organization
Organized by frequency from high to low - highest frequencies are in the middle of the cochlear nucleus, while the lowest frequencies are out towards the side
Somatic nervous system
Controls voluntary movement; info that is going into the body Ex: facilitates the decision to run or jump in response to a challenge or threat (BUT needs help from the sympathetic nervous system to execute the brain's motor demands)
How is the validity of a research model or approach determined?
Convergence of evidence from multiple types of data usually speaks to the validity of a model / approach
Superior orbital sulcus
Cortical area implicated in context perception; continuously updates knowledge of current context
Parahippocampal cortex (PHC)
Cortical area that is sensitive to contextual relations based on the presence of other objects; contextual associations that are sensitive to visual appearance & that are organized in a hierarchy of spatial specificity
Codeine
Cough suppressant & analgesic
Hydrophobic
Oriented away from water & toward the inside of the layer
Where is the pineal gland located?
Above the thalamus; the top of the diencephalon
What does Weber's law contrast with?
Absolute threshold
What type of transport system is the sodium potassium pump: passive or active?
Active
Diurnal
Active during the day
What has allowed us to learn a lot about the function of the basal ganglia?
Parkinson's disease
What is the function of research exploring how Schwann cells facilitate the regeneration of PNS-damaged axons following the onset of neurodegenerative disease or an accident?
Could be used to develop interventions to regenerate CNS myelin (which does NOT naturally occur)
Where do nerves in the parasympathetic nervous system extend from?
Cranial & sacral areas
THC
Primary active ingredient in marijuana
Ribosome
Primary site of protein synthesis
What are the only types of mammals that are trichromats?
Primates
Firing of the next cell is _____________
Probabilistic (i.e. doesn't necessarily happen)
What does damage to the corticospinal tract often lead to?
Deficits with their forelimbs (ex: issues flexing fingers independently to pick up a pencil with 2 fingers)
What accounts for the bulk of a neuron's surface area?
Dendrites
What is the shape of DNA?
Double helix
Explain the structure of DNA
Double-helix shape consisting of pairs of nucleotide bases
Explain how elaboration relates to adaptation
Elaboration of the same basic brain structure allows animals to cope with their environment (i.e. adaptation) --> different animals elaborate different portions of their brain Ex: elephant-nosed fish has a large electrical organ that can send out signals into murky water, which then requires a large portion of the brain to be dedicated to it
Explain how the fundamental integrity of the DNA code is protected against premature changes
Epigenetic changes are temporary (though they can last across generations) & if the environmental pressures are altered, the genetic modifications will fade over time & revert to the original expression pattern
Intractable epilepsy
Epilepsy that is NOT responsive to drugs to stop the seizures
Magnetoencephalography (MEG)
Assesses brain function by detecting the magnetic fields generated by neural networks
How is saltatory conduction possible?
Because of the insulation provided by the oligodendrocytes & Schwann cells that build the myelin sheaths that wrap around & insulate axons
Antagonists
Block or decrease the effects of specific neurotransmitters
How do local anesthetic drugs (ex: Xylocaine, Novocain) work?
Block the sodium channels, thus blocking the influx of sodium & the messages telling the patient that they are experiencing pain
Which modulation of cholinergic synapses does NOT happen very often with ACh?
Blocking reuptake with catecholamines
How does caffeine work?
Blocks receptors of adenosine, especially adenosine A1 & A2A receptors
Central nervous system (CNS)
Brain + spinal cord
Area postrema
Brain area located in the medulla; "the vomiting center" that has a weak blood-brain barrier to enable it to detect & expel threats before they penetrate the body's other defenses
Vertebrate neural control model
Brain exerts neural control over the body
Concussions
Brain injuries with symptoms ranging from loss of consciousness to a sustained headache to memory loss
Relative brain size
Brain mass in proportion to body mass
Gyri
Bulges / ridges
Upper motor neurons
Bundles of axons extending from the cell bodies in the motor cortex; encompass anything above what is in the ventral horn of the spinal cord & synapse on lower motor neurons
What is one way to tell the gestational age of the baby in utero?
By examining the amount of white matter during the 3rd trimester
How do different areas in the cortex work to help us see?
By extracting specific features (i.e. feature extraction)
What is located in between the meninges & the brain?
CSF
Endothelial cells
Exist in the brain's vascular system
Lower motor neurons
Exist in the gray matter of the spinal cord, specifically arising from the ventral horn; activate the movement of specific muscles & are the only thing that can actually make the muscle move
Distal
Farther from the CNS
What is used to determine the extent of damage after a TBI?
Glasgow coma scale
Sulci
Grooves / valleys
How do the otolith organs work?
Have hair cells that stick up into the space above them, where there are calcium crystals that put weight on the hair cells, thus allowing them to detect if they're being smushed or deflected so they know how the body is oriented with gravity
Cervical nerves
Innervate the top of the head, the back of the head, the shoulders, & some parts of the forearms
Tracts
Refers to cabled axons within the CNS
Inner pyramidal cell layer
Large pyramidal cells; motor action
When does myelination occur during brain development?
Late in brain development --> it is the final maturation in a neuron
What is a disadvantage of neuroimaging techniques?
Leave out important information occurring at a more microscopic/cellular level
Ventral root
Leaves going out of the spinal cord
Cyclic guanosine monophosphate (cGMP)
Levels of it regulate the open or closed position of sodium ion channels; in the presence of light, it has lower levels, which leads to closed sodium channels, hyperpolarization, & reduced levels of neurotransmitter release
What is the adequate stimulus for photoreceptors?
Light (& sometimes tactile pressure on the eyelid, which creates bursts of apparent light)
Paul Broca
Located a patient who, after suffering from epilepsy, could no longer speak --> his brain showed damage in the same area ("Broca's area") that Jean-Baptiste Bouillaud's & Simon Aubertin's patients who had language deficits had brain damge
Parasympathetic nervous system
Regulates baseline functions necessary for survival; "rest & digest" system that works in opposition to the sympathetic nervous system by relaxing the body
Heredity
The biological transmission of physical & mental characteristics from parent to offspring
Medulla oblongata (myelencephalon)
Regulates fundamental life-supporting systems such as respiration, blood pressure, arousal, & muscle tone that are essential for survival; most ventral (lower) area of the brain / most caudal part of the brain that is just rostral to the spinal cord
Ischemia
The disruption of blood flow
Neuropharmacology
Looks at how you use drugs to affect the way that a synapse works
Are endocannabinoids stored in vesicles?
No - they are synthesized & released as needed by the plasma membrane in the postsynaptic neuron
Does neurotransmitter exchange occurring across a single synapse alter the membrane potential enough to reach threshold?
No
Does the cornea have a blood supply?
No
Has a definitive biological cause of ASD been identified?
No
Is area V4 activated when people focus on black-and-white stimuli?
No
In mammalian species, does the # of neurons reliably increase with brain mass?
No Ex: if the rodent brain was enlarged to be the same size as the human brain, it would have only 12 billion neurons; if the rodent brain was enlarged to have the same # of neurons as a human brain, it would weigh 35 kg
Is the substantia nigra considered part of the basal ganglia?
No (but it is nearby & communicates with the basal ganglia structures)
Is signal processing in the post-synaptic cell binary?
No - about 32 different things can happen in the post-synaptic cell
Do antagonists bind to receptor sites?
No - do NOT result pharmacological response because they only partially fit in the receptor site; however, this does block that receptor site so neurotransmitters or agonists can NOT access it
Do we see the world in specific details like lines & edges?
No - we see the world in scenes
Retrograde neurotransmitters
Released by the postsynaptic neuron & diffuse backward to the axons of presynaptic neurons, where they affect relevant receptors
Opponent cells
Respond to 2 different colors
Pacinian corpuscles
Respond to deep pressure
What percentage of the cortex participates in visual functions in the macaque? In humans?
55% in the macaque, 30% in humans
How long does it take for rods to take over in a dark room (i.e. for your eyes to adjust)?
7-10 minutes
How long does the developing fetus have for proliferation?
8 months (because can NOT begin proliferation until the neural tube is formed)
Axon collateral
A branch off of an axon
Spinal cord is ______________ in nature
Segmental
What does GABA inhibition lead to?
Seizures & death
Pituitary gland
A component of the endocrine system that is a master gland that controls most of the other glands in the body; after receiving information from the hypothalamus, it works by triggering the release of various hormones, which travel to destinations throughout the body
Epilepsy
A condition characterized by recurrent seizures that can lead to poor quality of life due to uncontrollable behavior
Human Connectome Project
A large-scale cooperative effort to map the circuits in the human brain; hopefully will result in revealing structural & functional maps of the brain's neural wiring that could potentially have some clinical applications for neurological diseases
What is special about the platypus, in regards to touch?
The platypus has a very sensitive bill, which they use to explore their surroundings as they search for food or other resources
Gamma (γ) aminobutyric acid (GABA)
The principle inhibitory neurotransmitter in the CNS
Morphine
The principle psychoactive substance in opium
Bidirectional angular accelerometers
The technical term for the semicircular canals
What does conservation for evolution allow for?
The use of animal models for studying human brain development
Neurotransmitters
The various types of neurochemicals exchanged between neurons
What is hue determined by?
The wavelength of the light
Timbre
Tone color; refers to how harmonics come around a single note to give it flavors / tones Ex: an "A" note on the piano & the cello is the same not BUT they have different harmonics going into them
Dorsal view
Top down view
Ventral
Toward the bottom / chest / belly
What do multisensory neurons contrast with?
Traditional sensory neurons
Afferent nerves (sensory nerves)
Transmit info from the environment or other body areas toward the CNS
TBI
Traumatic brain injury
Resting tremor
Tremor goes away during voluntary movement; contrasts with an intention tremor (which is NOT part of Parkinson's disease)
Robert Bartholow
Used Fritsch & Hitzig's technique on one of his patients to see what might happen
Dose-response curves
Used to determine the lowest amount of drug necessary to produce optimal outcomes; differ depending on the outcome measure
Otolith organs
Utricle & saccule; one is on the x plane & the other is on the y plane
What happens when the iris contracts? What happens when it relaxes?
When it contracts, it covers up the pupil so it looks constricted; when it relaxes, the pupil becomes larger & dilated
Intervertebral foramen
Where the roots enter & exit in the space between the vertebrae
Can movement errors occur with sophisticated Bayesian calculations?
Yes - especially when there are too many variables to accurately process OR a false belief about physical circumstances exists
Do any neurons release more than 1 kind of neurotransmitter? Explain this process
Yes - some neurons release more than 1 kind of neurotransmitter but in this case, each vesicle still has the same composition (ex: 40% of one neurotransmitter, 60% of another)
James Watson & Francis Crick
After seeing Rosalind Franklin's x-ray evidence of DNA's double-helix shape, they constructed an accurate model of DNA
Personal Genome Project
Aims to collect both genetic sequencing & lifestyle data for 100,000 individuals to investigate how genes interact with the environment to form human traits (i.e. how genetic variation contributes to behavioral variation)
Genes
Biological factors containing the inherited info for a particular species for varying forms of physical characteristics
What did fMRI lead to the emergence of?
Cognitive neuroscience
Electroencephalography (EEG)
Detects the electrical activity of large populations of the brain's cells; electrodes placed on the scalp pick up electrical activity across the brain, which is then amplified & recorded on a computer
Heterozygous
Different alleles (one dominant, one recessive)
What processes are related to ultimate causes? What questions are associated with them?
Function & evolution; "why" questions
Explain the complex process from DNA to behavioral expression
Genes --> proteins --> neurons --> neural circuits in targeted brain areas --> multifaceted behavioral & cognitive response
Phenotype
Observable, physical characteristics
Translation
Outside the nucleus, a ribosome assembles amino acids into proteins based on the order of the nucleotide bases in the mRNA; tRNA brings amino acids to the ribosome & organizes them based on the order of mRNA base pairs
How does the hippocampus function in uncertain situations?
Processes escape & threat situations aligned to the worst possible outcome
What is the benefit of case studies?
Provide a spring board for learning about brain conditions that are not easily studied in a lab
Context
Refers to the circumstances surrounding an event & the unique interactions that exist among behavior, the brain, & one's external & internal environment
Nikolas Tinbergen
Reinforced the importance of understanding short- & long-term influences on animal behavior by describing relevant questions that should be answered, which required an understanding of the mechanisms, development, function, & evolution of behavioral responses
Brain circuits ("neural networks")
Represent multiple brain areas linked in critical ways so that they are concurrently involved in certain functions
What is a disadvantage of fMRI?
Requires participants to be very still in the scanner, which restricts the type of tasks that can be performed
What was the practical goal of the Human Genome Project? What has been the reality?
The goal was that it would allow scientists to understand the genetic causes of various diseases & thus create new treatment opportunities BUT actual progress has been slow
What is biological psychology committed to recognizing?
The influence of BOTH the brain & the environment on behavior
Epigenetics
Variations in life experiences & the environment can alter the expression of proteins dictated by the genetic template; gene-environment interactions can alter the production of genetically prescribed proteins
What discipline is play usually categorized in?
Neuroethology
Saggital section
Opens up the brain so you can see the left vs. right side
Ketamine
A hallucinogenic anesthetic that is used to treat depression
Thrombospondin
A protein that facilitates synaptogenesis
Diffusion
All molecules want to evenly space out from each other
Sensation
Detecting information about our environmental context
What is the location of the motor cortex in the frontal lobe?
On the pre-central gyrus
Blind studies
Patients do not know which group they have been assigned to
Endogenous
Produced within the organism itself
Gap junction
Spaces of about 2-4 nanometers that exchange electrical currents
Neuroplasticity
The brain's ability to restructure itself
What were the results of the of the study investigating the effects of maternal exposure to indirect ("bystander") stress on prenatal neural development? (3)
- bystander stress was NOT related to the duration of the pregnancy or the # of pups delivered - bystander stress was associated with decreased dendritic length & increased spine density in the orbitofrontal cortex of both male & female pups - bystander stress was associated with increased spine density & decreased neuron count in the hippocampus for female pups; only associated with increased spine density in the hippocampus for male pups
Which tracts primarily innervate our limbs? (2)
- corticospinal tract - corticorubro spinal tract
What were the results of a study examining the effects of tactile stimulation on the recovery of adult male rats that had experienced lesions of the bilateral medial frontal cortex? (2) What was the major conclusion?
- frontal-injured group that received tactile treatment (being stroked with a hairbrush) had success rates on a reaching task that were closer to those of a non-injured sham control group than the injured control group that received NO tactile treatment - tactile stimulation increased the arborization of the dendrites in the pyramidal cells adjacent to the lesioned area (an effect which is associated with increased neural connections) Conclusion: tactile treatment seems to facilitate function recovery from brain injury
What are the amino acid neurotransmitters? (3)
- glutamate - GABA - glycine
What are some reasons that hawks (& other birds of prey) have excellent visual acuity? (5)
- large eyes proportional to their head size that are positioned at the front of the face contributes to superior depth perception & binocular vision - have 2 foveae in each eye - have up to 5x more photoreceptors per square millimeter than humans - can keep their head very steady & use compensatory motor reflexes to maintain a consistent position in order to keep their eyes on the target - sensitive to objects moving more slowly than humans can perceive
What are some mechanisms that increase conduction velocity? (2)
- larger axon diameter - myelinated axons
What are some common types of ligand-gated channels?
- ligand-gated Na+ channel - ligand-gated K+ channel *these channels are specific to ions
What are some limitations of field research? (2)
- little knowledge about the histories or extenuating circumstances of the animals that could affect their responses - less control of other variables (ex: diet, social contact)
Where is norepinephrine produced? (2)
- locus coeruleus - sympathetic nerves
What are some submodalities of exteroreceptors? (3)
- mechanoreceptors - thermoreceptors - nocioceptors
What is a study showing the importance of early experience for the visual system's healthy development?
- method: fitted kittens with goggles / glasses that had small vertical slits to see through on one eye & horizontal slits to see through on the other eye; when the kittens grew up, they removed the goggles.& tested from their visual cortex when they were exposed to different line orientations - results: found that the cats' eyes that were exposed to horizontal lines during development could only perceive horizontal lines of light & those that were exposed to vertical lines could only perceive vertical lines of light
What is a study showing that increasing target sites leads to the survival of more cells?
- method: transplanted 4 extra nerves down one side of a frog - results: found that it had tons of neurons making functional connections on the side with the extra limbs BUT had the normal amount of neurons on the other side
What can reflexes be? (2)
- monosynaptic - bisynaptic
What are some studies showing the effectiveness of constraint-induced movement therapy? (2)
- study found that children with cerebral palsy (who had severe paralysis on one side of their body) who were assigned to undergo constraint-induced movement therapy where they wore a sling on their functioning limb developed improved dexterity of their impaired limb & better movement efficiency, leading to increased use of the affected limb - study found that rats with damage to the spinal cord who were trained in a reaching task using their impaired limb showed higher levels of cortical BDNF & improved functional movement in the task
What are some studies showing evidence of humans undergoing use-dependent cortical reorganization? (2)
- study found that it was more difficult for subjects to differentiate stimulation of the thumb & pinky finger after extensive training with simultaneous stimulation of the 2 fingers because the dedicated cortical areas for each finger had become overlapped - study found enlarged cortical representation of the fingers in the right hemisphere in string players who became more sensitive to sensation generated from their individual fingers on their left hand as they play their instruments
What steps occur once the brain is damaged by an external or internal destructive force? (3)
- subdural hematoma - ischemia - ionic flux
What is some evidence that sensory systems, especially smell, played a significant role in the evolution of the mammalian brain? (2)
- the brain of the Morganucodon (mouse-sized animal that lived 205 million years ago) was 50% bigger, relative to body size, than the brains of reptiles at the same time --> specifically the olfactory bulbs & olfactory cortex were enlarged in comparison - the brain of the Hadrocodium (a small mammal that lived 10 million years after the Morganucodon) was 50% larger than the Morganucodon, specifically due to an increase in brain tissue supporting enhanced olfactory capacities
What are some things that neuropsychopharmacologists must understand about drugs they are researching? (3)
- therapeutic effects - pharmocokinetics - pharmocodynamics
What are 3 types of dendritic spines? Describe them
1) *thin spines* = fine filopodialike extensions 2) *stubby spines* = short 3) *mushroom spines* = have a large, bulbous head
What are 3 important patterns for brain development?
1) *the brainstem matures 1st*, while brain areas that are higher up in the cerebral cortex are formed later 2) *motor systems come online 1st, before the sensory systems* 3) *different kinds of neurons in different parts of the brain*
What is the normal range of loudness?
0 dB to 90 dB
What does 1 Hz equal?
1 oscillation / sec. Ex: 100 Hz = 100 oscillations per second
What percentage of the population is affected by synesthesia?
1%
What were the 3 things that Hodgkins & Huxley needed to determine whether the brain had electrical activity?
1) *2 electrodes* (one placed in the axon & another outside of it) to measure the relative difference in charge 2) built an *amplifier* to boost the tiny electrical signal so it could be seen 3) *oscilloscope* to register the signal
What are the 2 types of receptors that glutamate molecules activate? Why?
1) *NMDA receptor* - because of its affinity for N-methyl-D-asparate 2) *AMPA receptor* - because of its affinity for alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid
What are 3 things that can happen on a post-synaptic cell?
1) *depolarization* --> excitatory post-synaptic potential (EPSP) 2) *flat response* 3) *hyperpolarization* --> inhibitory post-synaptic potential (IPSP)
What are the 2 areas of the mature mouse brain in which neurogenesis occurs?
1) *subgranular zone* of the dentate gyrus in the hippocampus 2) *subventricular zone* of the lateral ventricle
What are 6 common categories of psychoactive drugs?
1) CNS stimulants 2) CNS depressants 3) analgesics 4) hallucinogens 5) drugs with diverse CNS effects 6) psychotherapeutics
Cerebellar cognitive affective syndrome
A clinical disorder caused by cerebellar damage; symptoms include impairments in executive function, language, sequencing events, & visuospatial abilities
How many connections need to be made in the brain?
10^15 connections
How many surface colors can humans discern?
2.3 million
What is the range of sound vibrations that humans can respond to?
20 - 20,000 Hz (or 20 kHz)
Ossicles
3 small bones located in the middle ear that transmit air vibrations; collectively, work as an amplifier to take the incoming sound information & deliver it to the oval window
Semicircular canals
3 structures in the inner ear that allow you to sense things on 3 different planes so that you always know where your body is in space
What is the limit for loudness idea of sound localization?
3-4 kHz
What percentage of the cortex is devoted to decoding light into images & complex scenes?
30% of the cortex
How many genes are there in the human genome?
30,000 genes
How many pairs of spinal nerves are there?
31
Spinal nerves
31 left-right pairs of nerves in humans that shuttle info to & from all areas of the body
How many times a day is CSF renewed?
3x per day
Explain the high energy cost of the sodium-potassium pump
40% of the neuron's metabolic resources are used to operate these pumping sites
What part of the electromagnetic spectrum can humans see?
400-750 nanometers
What is the percentage of a parent passing on the Huntington gene?
50/50 if they are affected by Huntington's disease --> this is unfortunate because by the time symptoms show up in midlife, people have usually already decided whether to have children
What percentage of the primate cortex comprises cortical association areas?
75%
How many neurons do humans have? How many miles of axon?
86 billion neurons; 93,000 miles of axon
Explain more closely how the basal ganglia structures work to process motor activity?
Cortex is constantly sending information to the caudate / putamen with information about what's going on at that particular space & time in the brain --> the globus pallidus makes sense of these inputs & is constantly sending *inhibitory info (GABA) to the thalamus *BUT when the caudate / putamen gives information to the globus pallidus, it will NOT inhibit the thalamus because the caudate / putamen has then inhibited the globus pallidus, leading the thalamus to send an excitatory signal to the cortex
What is a study showing that exercise benefits the brain?
Found that elderly subjects participating in exercise programs had *larger pre-frontal & temporal lobe gray matter volumes* than their sedentary counterparts
What is a study showing pro golfers "choking" under pressure?
Found that the performance of golfers declined when asked to think about the movement of their elbows prior to taking a shot
Reticulospinal tract
Information travels from the reticular formation in the central part of the brainstem
Tectospinal tract
Information travels from the tectum in the superior colliculus to the spinal cord
Medium spiny neurons in the caudate / putamen
Inhibitory neurons that use GABA
What is critical for predicting the extent of damage following a brain injury?
Ischemia
What method is used to examine neuronal densities?
Isotropic fractionation
What can listening to loud noises do to the auditory system?
It can "overdo" the system, leading to accelerated hearing loss
What did Leah Krubitzer do?
Mapped the specific cortical areas of many mammals & noted how the size of various cortical areas changed depending on the extent of use of various sensory & motor systems --> suggests that there are cross-species similarities in the genetic factors involved in cortex development BUT interspecies differences emphasize the importance of the animals' lifestyle in the development of these fundamental areas Ex: visual cortical area is largest in the opossum, auditory cortex is largest in the vole, & somatosensory cortex is largest in the mouse
Connectomics
Mapping brain tissue in great detail; can give us new insights into brain areas
Somatotopic maps
Maps of correspondences between specific areas of the body & specific areas in the brain's somatosensory system
What is an example of a class of nestin cells?
Mature cells that are found in adult brain areas, such as the basal forebrain, hippocampus, & striatum
Allostasis
Physiological changes in response to varying demands
Why does the action potential only move in 1 direction?
Refractory periods "follow" behind the action potential & because the area that just had an action potential is too busy re-establishing resting membrane potential, it can NOT have another action potential --> the hyperpolarized refractory period prevents things from going backwards SO it can only move in 1 direction
Prosopagnosia
The inability to recognize faces; caused by damage to the fusiform face area
Repolarization
When the potassium eflux occurs due to the voltage-gated K+ channels opening, thus making the cell more negative / more polar
The root
Where the spinal nerve connects to the spinal cord
What are some common neuroimaging techniques? (5)
- CT - PET - MRI - DTI - fMRI
Johann Spurzheim (3)
- Gall's assistant - removed some of the negative mental faculties from Gall's list - popularized the term "phrenology"
What are the pairs of nucleotide bases?
- adenine & thymine - cytosine & guanine
What are some other results from enriched environment studies? (2)
- among rats who experienced brain trauma & a subsequent transfer of healthy neural tissue, those who were housed in an enriched environment regained more lost function --> enriched environments facilitate recovery of function after brain trauma - found that rats in enriched natural environments (compared to enriched artificial environments) had higher levels of DHEA (a hormone involved with resilience) that contributed to increased emotional resilience / reduced stress response when subjected to a stressful forced swim task
Which specializations of biological psychology largely work with human subjects? (3)
- cognitive neuroscience - psychophysiology - neuropsychology
What are some examples of adaptations / natural selection? (2)
- finches with beaks that were best adapted to successfully retrieve food were the finches most likely to survive long enough to reproduce, thus passing to their offspring the likelihood of having a similarly adaptive beak - black iguanas can blend in with their environment (black rocks), quickly escape the water after being thrown in (because their only predators are in the water), sun on black rocks to warm up (because they are cold-blooded), & sleep in huddles to warm up
What were some unexpected findings from the Human Genome Project? (3)
- humans have only about *20,000-30,000 genes* (NOT 100,000, which was hypothesized, & only 2x the number of genes found in fruit flies) - only *1.5 of DNA actually consists of genes for protein production*; the function of the other 98% ("junk DNA") is unknown - only 0.1-0.5% of the entire genome varies across individuals
Franz Joseph Gall (2)
- hypothesized that certain brain structures were associated with specific *mental faculties* (functions) - specifically, that higher-functioning areas of the cortex would be represented by a bulge in the cortex & that this cortical bulge could be assessed by feeling the skull with one's hands - measured people's skulls & questioned them about specific abilities to determine 27 mental faculties that were specifically localized on the brain's cortical surface
What is a study using ERPs?
- method: compared participants with narcolepsy & Parkinson's disease with a healthy control group by looking at ERP records while they viewed neutral vs. humorous images - results: participants with narcolepsy had larger ERP responses to humor, while those with Parkinson's did NOT have higher ERP amplitude
Enriched environment study
- method: compared rats placed in complex, enriched environments with those who were housed individually or in cages with no enriching objects; after a month, the rats' brains were removed & examined - results: rats in the enriched environment showed increased physical activity & social interactions, as well as had thicker areas of the brain (ex: the cortex) & more connections among the cells of the nervous system - conclusion: brains are NOT fixed at birth; context (external environment) can influence brain structure
Which specializations of biological psychology largely work with nonhuman subjects? (3)
- psychopharmacology - physiological - comparative
Transcription
In the nucleus, DNA partially unwinds; mRNA assembles opposite one DNA strand as its mirror image
_______________ in challenging environments leads to death. Examples? (2)
Inflexibility Ex: mammals are more generalists than specialists in their food preferences Ex: raccoons & rats have adapted to eating novel food (esp. human food, in the case of rats) from almost any source
Case studies
Investigations of individuals who have suffered injury or disease that have had an impact on behavior or mental functions Ex: Tan, whose brain injury & language impairment led to the discovery of Broca's area Ex: Dante Autullo, who accidentally shot a nail into his brain
Phrenology
Mapping of mental characteristics to bumps on the skull; refers to Gall's theory of brain localization
What is an advantage of fMRI?
Safer & less expensive than the PET scan
Homozygous
Same alleles (i.e. both dominant or recessive)
Magnetic resonance imaging (MRI)
Shows brain structure through a magnetic field
Ribonucleic acid (RNA)
Similar to DNA BUT is single-stranded & has the base uracil instead of thymine
What is a problem with the Personal Genome Project?
Storage of immense amounts of genetic data
What happens when a dominant gene is paired with a recessive gene?
The characteristics of the dominant gene are expressed
Nucleotide bases
The chemical building blocks of DNA (adenine, thymine, cytosine, guanine)
White matter
The communication pathways in the brain
Human genome
The complete set of genes contained within each of us
Human Genome Project
The effort to decode the human genome; was completed primarily by the NIH (led by Francis Collins) & Celera Genomics (led by Craig Venter)
Gray matter
Neuronal cell bodies
Peptide neurotransmitters
Consist of endorphins, oxytocin, vasopressin, & substance P
Hippocampus
Involved in learning & memory, especially short-term memory
Explain the 2 major divisions of the spinal cord
1) dorsal horn & dorsal root 2) ventral horn & ventral root
What is a temporary treatment for Parkinson's disease?
*L-dopa* = the precursor molecule to dopamine, which can cross the blood-brain barrier & allow the body to manufacture dopamine in the absence of dopamine-producing neurons
What are the 3 layers of the meninges?
1) dura mater 2) arachnoid mater 3) pia mater
What are the 2 dimensions of context?
1) environmental context 2) experiential context
Functional genome
Consists of immune function, movement efficiencies, anatomy, motivation, etc.
What are 2 processes by which neurotransmitters terminate their activation of postsynaptic receptors?
1) enzymatic deactivation 2) reuptake
What are 2 potential results when the neurotransmitter & receptor bind?
1) excitatory postsynaptic potential (EPSP) 2) inhibitory postsynaptic potential (IPSP)
What is ACh synthesized from?
*Acetyl coenzyme A* (from metabolism) + *choline* (from metabolism or diet)
Amyloid plaque
Consists of protein (β-amyloid) found in spaces between neurons
Signal processing in the pre-synaptic cell is ___________. What does this mean?
*Binary* - all-or-non response
What are 3 categories of modalities in the somatosensory system?
1) exteroreceptors 2) interoreceptors 3) proprioceptors
What are 2 types of fibers that make up skeletal muscle?
1) extrafusal fibers 2) intrafusal fibers
What is the head region of the phospholipid bilayer? What is the tail region?
*Hydrophilic* phosphate head region; *hydrophobic* lipid tail region
What is all the info that must be integrated in order to decide whether an action potential will be generated? (5)
- hierarchical synapses - temporal summation - spatial summation - ionotropic vs. metabotropic receptors - excitatory vs. inhibitory synapses
What is used as the control group in addiction studies? Why?
*Non-drug-abusing participants* - it is NOT possible to conduct a controlled experiment where people participate before & after becoming drug abusers
What are some characteristics of sodium ion channels? (3)
- high density - industrious - 1 channel can transport up to 100 million ions per second (SO must open & close at the correct time)
What is the double function of myelin sheaths?
1) facilitate saltatory conduction 2) provide insulation for the axons
What are 3 theories / proofs for how frequencies are coded in the auditory system?
1) frequency theory 2) volley theory / cross-fiber theory 3) place theory
What are the 3 major divisions of the brain?
1) hindbrain 2) midbrain 3) forebrain
What is a glycine antagonist? What does glycine system activation result in?
*Strychnine* --> activation results in convulsions, muscle cramping, & respiratory problems
What are 3 dimensions of the light stimulus?
1) hue 2) brightness 3) saturation
What are some key characteristics of a graded potential? (3)
- *move passively in every direction* - graded = *incremental* so it starts out strong & then gets weaker due to it dissipating over time - *fast* --> travels at 1.86 x 10^5 miles per second (very close to the speed of light)
What are some key characteristics of an action potential? (3)
- *only travels in 1 direction* - *all-or-none* --> signal does NOT diminish - *slow* --> travels at 100 meters / second
What are 3 major places in the brain that visual information goes?
1) hypothalamus, specifically the suprachiasmatic nucleus 2) superior colliculus 3) lateral geniculate nucleus (LGN)
What are some theories regarding the lateralization of certain brain functions? (2)
- "too many cooks in the kitchen" --> ex: stuttering may be caused by both hemispheres actively participating in language production - more economical to assign certain tasks to a specific hemisphere because more can be accomplished with minimal brain activation
What are the functions of astrocytes following a TBI? (3)
- "vacuum up" excessive glutamate to prevent additional neuronal loss - scavenge for *oxygen free radicals*, which can also harm vulnerable neurons - modify levels of extracellular potassium & hydrogen ions to provide a buffer against edema (swelling)
What were the results of Hodgkins' & Huxley's experiments?
- #1: when both electrodes were placed on the outside of the axon, there was NO difference in charge between the 2 electrodes - #2: when one was placed in the axon & the other was placed outside, there was a negative difference down to about -70 mV (i.e. resting membrane potential) - #3: when the electrode in the axon was stimulated, the squid flew off the table (& on the first try, ended up destroying the oscilloscope & amplifier) & the charge got very positive, then slightly more negative, & then stabilized against at -70 mV (i.e. had an action potential)
In rats, what areas of the cortex are the most prevalent? (3) What does this suggest?
- **whiskers - nose - mouth Suggests that these areas are very important for survival
What are the divisions of the spinal nerves? How many are in each? (5)
- *8 cervical* spinal nerve pairs (C1-C8) - *12 thoracic* spinal nerve pairs (T1-T12) - *5 lumbar* spinal nerve pairs (L1-L5) - *5 sacral* spinal nerve pairs (S1-S5) - *1 coccygeal* spinal nerve pair
What are some GABA agonists? What does GABA system activation result in? (2)
- *alcohol* --> activation at the GABA system in the amygdala results in inhibition of the brain's cognitive & behavioral systems - *muscimol* --> activation results in intoxication & hallucinatory effects
What are some types of synaptic arrangements that are found in the CNS? (4)
- *axodendritic* = axon to dendrite - *axosomatic* = axon to soma - *axoaxonic* = axon to axon - *dendrodendritic* = dendrite to dendrite
What are the key functions of astrocytes? (5)
- *fill in the spaces* between neurons - *transport essential nutrients* from the brain's blood vessels to the neurons - *maintain a constant chemical environment* around the neurons by eliminating potentially dangerous remnants of dead cells & keeping the neurons supplied with ions & other things they need - help *regulate cerebral blood flow & communication between neurons* - involved in the *blood-brain barrier* --> *line all of the blood vessels & the surface of the brain* to prevent a barrier between the brain & the outside world
Where do adenosine receptors have their highest levels & what are the functions of these areas? How might this affect experiences while on caffeine? (3)
- *hippocampus & cerebral cortex* --> involved in learning, memory, & complex cognitive associations - *cerebelular cortex* --> involved in conscious awareness & various forms of cognition - *dopamine-rich areas, like the prefrontal cortex* --> may explain caffein's effect of increased attention & focus
What are some brain areas involved in play? Which aspects of play specifically? (3)
- *mesolimbic dopamine system* --> important for the reward aspects of play - certain areas of the *thalamus* (ex: the *parafascicular area*) --> regulate somatosensory input needed to choreograph specific play responses - *periaqueductal gray area* --> plays a role in switching between behavioral patterns, thus allowing it to regulate the play response
How does LSD work? (3)
- *partial antagonists of serotonin 2A (5-HT2A)* receptors in the brainstem (sleep & dreamlike effects), locus coeruleus (increased attention to novel stimuli), & the thalamus + reticular nucleus (disruption of the filtering of neural info) - may directly or indirectly affect *glutamate* - *indirectly inhibits GABA neurons* in the pyramidal cells of the cortex (enhances activation & suppresses filtering of neural activity)
What ions are higher in the extracellular space? (2)
- *positively charged sodium (Na+) ions* - positively charged calcium (Ca2+) ions
How do astrocytes increase synaptic excitability? (2)
- *release thrombospondin (a protein) that facilitates synaptogenesis* SO blocking thrombospondin release leads to impaired synaptogenesis - *secrete cholesterol*, which facilitates presynaptic function & releases neurotrophic factors
Where can auditory info go after arriving at the primary auditory cortex (area A1)? What happens at each of these areas? (2)
- *temporal lobe*: can help us identify certain sounds - *parietal lobe, specifically the posterior parietal cortex*: plays a role in spatial localization & guiding our movements in certain directions
What are some characteristics of dendritic spines? (2)
- *vary in size & shape* to provide opportunities for synaptic connections with other neurons - can *change their shape* over time to create changing connections
What is in the immune system's outer layer of boundaries? (2)
- 2 meters squared of skin - extensive network of mucosal-lined tracts in the digestive system
Explain the development of white matter from 2 weeks old to 1 year to 2 years
- 2 weeks: not much white matter - 1 year: there is a large amount of white matter - 2 years: there is even more white matter that is very intricate & somewhat resembles an adult brain
What happened in the ACC during the study that examined the development of abilities on a response inhibition task? (2)
- ALL participants showed decreased activation of the rostral ACC during trials performed correctly - in the incorrect trials, only adults showed a differential response characterized by an increase in dorsal ACC, which suggests that adults' use of the ACC in all trials results in more consistent & effective monitoring of responses
What are some theories regarding color vision? (3)
- Young-Hemholtz trichromatic theory of color vision - opponent-process theory of color vision - skin theory of color vision
What are some examples of places in which myelinated axons are especially important? (2)
- human sciatic nerve = extends from the base of the spine to the big toe; has the longest axon (up to 1 meter in length) - neural impulses moving up & down the long neck of a giraffe
How does marijuana work? (3)
- THC activates cannabinoid receptors - also can inhibit norepinephrine, ACh, glutamate, & GABA by acting on presynaptic receptors - activation of cannabinoid receptors affects GABAergic neurons so that they no longer inhibit dopamine neurons, thus causing an increase in the release of dopamine
Where is nestin expressed? (2)
- developing neurons - a specific type of nestin-expressing cells
What happens at 3 weeks, in terms of prenatal brain development? (2)
- a swelling appears that will ultimately develop into the human brain - tissue forms folds around a tube that will eventually result in the central canal surrounded by the spinal cord & in the more dorsal direction, ventricles surrounded by brain tissue
What are the "other" neurotransmitters? (5)
- acetylcholine - lipid-derived transmitters (ex: anandamide) - adenosine - certain gases (ex: nitric oxide, carbon monoxide) - purines
What are some key functions of microglia? (2)
- act as a *cellular clean up crew* by searching for dead cells & cellular debris (ex: blood) throughout the brain - *monitor the microenvironment* of the nervous system & are alerted to various threats
Camillo Golgi (2)
- advocated for the nerve net theory - developed a new histological technique (Golgi stain)
What supports the opponent-process theory of color vision? (2)
- afterimages - color-blindness & the way that people can be color blind
After synapsing on the olfactory bulbs, where do olfactory axons travel to? (3)
- amygdala - piriform cortex - entorhinal cortex
Where are Von Economo neurons located? (2)
- anterior cingulate cortical area - frontoinsular cortical area
What are some examples of apoptosis? (2)
- apoptosis occurs in our feet so we don't have webbed feet - in the trochlear nerve, you begin with 1,200 neurons on embryonic day 11 BUT then neurons are lost over time
What are some possible treatments for ASD? (2)
- applied behavior analysis - synchronized dance therapy
How are cilia arranged on the hair cells?
- arranged on an incline - linked together by *tip links*
What happens during early stage of myasthenia gravis? During later stages?
- as the body begins to get rid of ACh receptors, the body grows weak as the muscles go limp - in later stages, the muscles can stop working, which is especially a problem in the diaphragm muscle (needed to breath) so patients may eventually need to go on a ventilator
What were Santiago Ramón y Cajal's ideas regarding the aging brain & plasticity?
- at first, asserted that once the brain completed its development, it was fixed & immutable in adulthood - later on, began to see evidence of mutability / "restorative plasticity" in the adult nervous system, especially following damage
What does it mean to say that depressants have a dose effect?
- at low doses, produce relief from anxiety & disinhibition - at medium doses, promote sleep - at high doses, can cause anesthesia, coma, & even death
What are some ways that individuals who have been deaf since birth experience enhanced visual sensitivity & reorganization of the sensory areas of the cortex? (2)
- auditory cortex is activated when viewing sign language - have larger visual field areas than hearing individuals
What are some places that the spike-initiation zone can be? (2)
- axon hillock - axon initial segment
What are some of the brain's defense mechanisms against pathogens? (2)
- blood-brain barrier - backup surveillance to monitor the brain for signs of trauma or infection, done by microglial cells & immune cells that migrate into the brain
What are some brain changes associated with AD? (4)
- buildup of amyloid plaque protein - excessive number of neurofibrillary tangles - severely enlarged ventricles - shrinking of the hippocampus
How are layers in the LGN divided up? (2)
- by what type of ganglion cells are synapsing on the layer (X / parvocellular cells vs. Y / magnocellular cells) - according to whether information is coming from the contralateral eye or the ipsilateral eye
What do both rods & cones consist of, in terms of their anatomical organization? (2)
- cell body - outer segment that is pointed toward the back of the eye & filled with membranes that contain photopigment
What are some brain areas that play a role in the transformation of an athlete from novice to expert? (3)
- cerebellum - neurons in the primary motor cortex - mirror neuron system
Where are nicotinic cholinergic receptors located? (9)
- cerebral cortex - striatum - hippocampus - thalamus - substantia nigra - ventral segmental area - locus coeruleus - raphe nuclei - autonomic nervous system in PNS
What are some examples of electrical synapses? (2)
- common in invertebrate & cold-blooded vertebrate species - exist temporarily while chemical synapses are being formed in mammalian nervous systems
What causes the decrease in processing speed as we age? (4)
- decreasing brain weight - shrinkage of neurons - decreased synaptic density - loss of dendritic spines
What are the unique characteristics of neurons, in comparison to other cells? (2)
- dendrites - axon
What are some neurochemicals involved in play? (4)
- dopamine in the mesolimbic system - endogenous opioids - serotonin - growth factors
What is the composition of the cell membrane? (2)
- double layer of phospholipids that isolates the cell's inner components from the extracellular fluid - porous cell membrane (contains channels that can open)
What are some things that the brain's preparedness to form habits may contribute to? (3)
- dysfunctional behavior (ex: addiction, OCD) - cultural / religious rituals - superstitious behaviors
What lure sodium to the inside of the cell once the sodium ion channels open? (2)
- electrical gradient - concentration gradient
What are some potential mechanisms of neural synchronization leading to seizures? (3)
- electrical synapses & gap junctions - electronic screen game-induced seizures / video-game epilepsy - excessive growth of collaterals
How can you induce seizures in rodent models? (2)
- electrically stimulating the brain to trigger action potentials - convulsant drugs that result in involuntary muscle contractions
What are some examples of the diverse effects of pheremones? (2)
- eliciting aggression in conspecific males - triggering sexual receptivity in females
What are some of the costs of play? (3)
- energy expenditure - more easily noticeable to predators - exposes them to risk of injury
What are some differences in the brain of blind individuals? (2)
- enhanced auditory capabilities from the neural network integrating auditory & tactile sensory domains - more neural connections between the primary auditory & visual cortical areas
What are some of the endogenous variations of morphine? (2)
- enkephalin - endorphins
Where are some different places in the brain that olfactory information goes? (4)
- entrohinal cortex in the hippocampus - piriform cortex - amygdala - hypothalamus
What are some modes of neuroplasticity? (2)
- establishing new neuronal connections - restructuring the neuron's cytoskeleton
What are some supporting roles that astrocytes play in neural transmission? (2)
- extended their fine membrane processes to ensheath BOTH the synapses & the fine blood vessels, which allows them to monitor & control levels of ions in the extracellular space - possess receptors for many neurotransmitters
What is some evidence that the cerebellum may also be involved in non-motor functions? (2)
- extensive connections between the cerebellum & BOTH sensorimotor & association areas of the cerebral cortex may explain its role in motor & cognitive functions - patients with cerebellar lesions have identified non-motor symptoms (ex: reduced pleasure, anxiety, repetition of responses, aggression)
What holds the eye in the optic socket? (2)
- extraocular muscles - optic nerve
What are some examples of functions that are generally only located on one side of the brain? (2)
- facial recognition tends to be on the right side of the brain - language is on the left side of the brain for about 90% of right-handed people
What are some brain differences in patients with CTE? (4)
- general atrophy in the cerebral hemispheres - specific loss in the temporal lobe, thalamus, hypothalamus, & brainstem - enlarged ventricles - neural abnormalities, such as amyloid plaques & tangles of τ protein
What did Gustav Theodor Fechner do? (2)
- had an insight while laying in bed that prompted him to appreciate that intersections between the mind & the physical world could be investigated by measuring a person's perception in response to a changing material stimulus (i.e. psychophysics) - discovered the difference threshold / just noticeable difference (JND)
What are the key takeaways from the experiment with rats & running & stress hormones? (2)
- harmful increases in stress hormones are mitigated if the stressful experience occurs in the context of affiliative contact - without stress hormones, more energy is devoted to increasing neurogenesis rates
Why do people study development using the visual system as a model? (3)
- hierarchical setup where features progressively get extracted - easy to drive with light - maps that are translated from 3D to 2D in the brain
What happens when the ciliary process relaxes? What happens when it tightens?
- when it relaxes, the lens get fatter - when it tightens, the lens will shrink, allowing you to see something up close
Explain why the large size of the human brain is likely NOT its distinctive feature? (3)
- humans do NOT have the largest absolute mammalian brain size - humans do NOT have the largest relative brain size - the proportion of cerebral cortex mass to total brain mass in humans is NOT fully distinctive
What are some mechanisms of axoaxonic synapses altering the amount of neurotransmitter release across the synaptic cleft to the dendrite of the postsynaptic membrane of neuron C? (2)
- hyperpolarizing an axon terminal - altering calcium influx in an activated axon terminal
How does nicotine enter the body? (2)
- if smoked, nicotine enters the lungs on tiny particles of tar & then passes through the lungs - if snorted or chewed, nicotine is absorbed to a lesser extent by the mouth & nose membranes
What can cause cell death? (2)
- if the cell fails to locate the resources necessary for homeostatic functioning (ex: glucose & oxygen provided by blood) - release of excitatory amino acids, such as glutamate, which can be toxic to the neurons
What happens if the cilia is pushed in the direction it is supposed to move? What happens if the cilia is pushed in the opposite direction?
- if the cilia is pushed in the direction it is supposed to move, it will lead to depolarization, thus activating the cell - if the cilia is pushed in the opposite direction, it will lead to hyperpolarization, thus making it less likely that the cell will be activated
How can allostatic overload be avoided? (4)
- if the intensity of the stress response is relative to the intensity of the actual stressor - if the stress response stops when the stress ends - maintaining one's health so that the resources necessary to respond to stressful situations are available - avoid environments that frequently or constantly activate stress responses
What are some characteristic signs of Parkinson's disease? (3)
- inability to make voluntary movements - characteristic "shuffling" gait --> don't articulate their legs very well or use their upper torso - resting tremor
What are some ways that exercise affects the brain? (3)
- increased oxygen & nutrient delivery = increased neurogenesis - increased BDNF (neural growth factor) = increased cellular survival in the brain - increased angiogenesis, especially in the cerebellum & motor cortex
Where are some brain areas where FM-FM neurons have been found? (3)
- inferior colliculus - MGN - auditory cortex of echolocating bats
What happens to information that comes into the temporal hemiretina on either eye? How about information that comes into the nasal hemiretina?
- information that comes into the temporal hemiretina will stay on the same side - information that comes into the nasal hemiretina will cross (decasate) to the other side
How does alcohol work? (3)
- inhibits glutamate transmission by interacting with the NMDA receptors in several brain areas - enhances the effects of GABA by acting as an agonist - affects the dopaminergic system
What happens to the visual image as it enters the eye? (2)
- inverted - left-right reversed (i.e. input from the left visual field strikes the right side of each retina & is sent to the right visual cortex, while input from the right visual field strikes the left side of each retina & is sent to the left visual cortex)
What are some potential mechanisms of changes in neural excitability? (3)
- ionic balance maintaining the critical membrane potential may be disturbed - glial cells that interact with the neurons may alter the resting membrane potential in a manner that makes neurons more likely to fire action potentials - alteration of the principal excitatory or inhibitory neurotransmitters & their accompanying receptors
What have lab work in animals & pre-clinical studies suggested regarding the clinical efficacy of progesterone as a treatment for TBI? How about large-scale clinical trials?
- lab worsted in animals & pre-clinical studies in humans have suggested that individuals who receive progesterone have lower mortality rates after TBI - large-scale clinical trials have failed to replicate the beneficial effects of progesterone over placebo for TBI
What is some evidence that contradicts the stereotypes that teens are irrational & unaware of potential harm that may result from different behaviors? (2)
- logical reasoning of adolescents is similar to that of adults - lack of evidence that risk taking is related to an immature PFC
What are some of the psychological effects of alcohol in low doses? In high doses?
- low doses: improved mood, drowsiness, increased self-confidence, impaired judgement, muscle coordination - high doses: potential for acute alcohol poisoning
What are some unique characteristics / specializations of the organization of the cell layers in the fovea that allow it to have high spatial resolution? (3)
- lower cell density --> creates a clearer path to the photoreceptors - high density of photoreceptor cells - only contains cones
What is a brain structure with many glial cells? What is a brain structure that has very few glial cells?
- many glial cells in the thalamus (10 glial cells / 1 neuron) - very few glial cells in the cerebellum (1 glial cell / 25 neurons)
What are some potential complications of electrolytic lesion technique? (2)
- may also damage other brain areas because you can NOT damage a brain area without influencing other brain areas - individual differences among animals may lead the researcher to miss the area of interest
What are the parts of the hindbrain (myelencephalon & metencephalon)? (3)
- medulla oblongata (myelencephalon) - metencephalon - reticular formation
Explain the study that examined development of abilities on a response inhibition task
- method: children, adolescents, & adults were in an fMRI & had to look to the opposite direction of a stimulus that would appear on one side of a light (response inhibition task) - results: found a graded improvement on the task from childhood to adulthood, with late adolescents performing similarly to adults --> improved executive function abilities to complete response inhibition tasks throughout adolescence
Explain Ader & Cohen's study regarding immunology & neuroscience
- method: created a conditioned taste aversion by giving the rats sugar water with a drug that would suppress the rats' immune systems, thus producing symptoms of sickness; then used eyedrops to administer sugar water without the drug - results: found that the rats still experienced symptoms of sickness as if they were still consuming the drug - explanation: the rats had made an association between the sweet sugar water & the drug during the experiment, which requires cross-talk between the nervous system that detected the sweet taste of the water & the immune system that led to the sickness responses
What is a study examining whether some factor in the blood interacts with the nervous system to produce age-related declines in neurogenesis?
- method: did parabiosis on mice who were either both young (young-young), both old (isochronic, old-old), or varied in ages (heterochronic, young-old); also, blood from young mice was injected in some older mice (& vice versa) - results: found that when young mice received old mouse blood, their levels of neurogenesis decreased BUT when infusion of young mouse blood produced increased neurogenesis rates in the dentate gyrus of old mice
What is a study showing the brain areas involved in context / top-down visual processing?
- method: fMRI study in which subjects were exposed to 2 types of visual stimuli--one characterized by a strong visual context (ex: bowling pin, construction hat) & another characterized by a weak visual context (ex: camera, scissors) - results: found that when subjects were exposed to strong visual context objects, they showed increased activation in the PHC & retrosplenial cortex; also with tasks that required higher-order integration to continuously update the interpretation of the visual stimulus, the superior orbital sulcus was activated
What is a study examining whether neural alterations due to the infusion of old / young mouse blood resulted in behavioral & cognitive changes?
- method: gave a group of mice IV injections of either young or old blood; then tested them on a conditional fear task & a spatial memory task (radial arm water maze) - results: found that infusion of old blood into young mice resulted in impaired contextual fear conditioning & spatial learning / memory
What is a study showing the long-term impacts of uncorrected astigmatism?
- method: gave people who were 20+ years old with severe astigmatism & had them wear lenses that perfectly corrected their astigmatism - results: found that they simply couldn't see certain orientation lines, even though their visual system was corrected, because the higher levels of the cortex hadn't developed due to the lack of experience that would typically allow them to develop
What is a study investigating the precise movements in human males to determine the type of moves the females found the most attractive?
- method: had males come into the lab & dance, after which their movements were created into 3D avatars; then females rated the dance moves - results; the most attractive moves involved the speed & movement of the right knee, as well as variation in neck & back movements
What is a study regarding split-brain patients & ethical judgements?
- method: healthy & split-brain subjects had to make a moral judgement between a case in which a person accidentally killed her boss with rat poison vs. one in which she tried but failed to kill her boss with rat poison - results: found that split-brain patients (unlike healthy subjects) could NOT differentiate between the 2 scenarios from an ethical perspective by considering the person's intent to harm the boss - conclusion: BOTH hemispheres are important for making complex decisions with evidence from many sources; the right hemisphere in particular is important in making complex decisions, such as moral judgements
What is a study examining how the brain responds when a person experiences a self-generated vs. an other-generated tickle stimulus?
- method: participants went through fMRI scans during 4 conditions (self-generated movements producing tactile stimulation, self-generated movements w/o tactile stimulation, externally produced tactile stimulation, & NO movement / NO tactile stimulation) - results: found that when tactile stimulation was self-produced, *significantly less activity was observed in the somatosensory cortex, the anterior lobe of the cerebellum, & the anterior cingulate area of the frontal cortex*
Explain Otto Loewi's experiment with frog hearts
- method: prepared 2 frog hearts, one with intact nerves & the other without intact nerves - results: found that if he stimulated the vagus nerve of the first heart that was immersed in an acetylcholine solution (which slowed the heart rate) & then transferred this solution to the second heart, the transferred liquid solution slowed the heart rate, just as the stimulation of the vagus nerve had done; also found the results when stimulating an alternate nerve that was immersed in a solution that accelerated the heart rate
What is a study by W.T. Greenough showing the importance of early experience for proper neuronal wiring?
- method: raised rats for 6 weeks in either an enriched environment or an impoverished environment; then did the Golgi stain on them - results: found that the rats that were raised in the impoverished environment had a smaller # of dendrites, synapses, etc.
Explain a study examining the effect of social context on neurogenesis due to running among rats
- method: rats were divided into a socially housed running group, a socially housed non-running (control) group, an individually housed running group, or an individually housed non-running group; then spent 12 days running or spending time in their cage, while receiving daily injections of bromodeoxyuridine (a marker of new dividing cells) - results: found that in the running groups, the socially housed rats had more new cells than the socially isolated rats, while in the socially isolated groups, the socially isolated runners showed LESS neurogenesis than the socially isolated non-runners
Study in which domesticated animals were returned to their natural habitats
- method: released rats that had lived in labs for 200 generations into a barnyard that wasn't fully protected from predators - results: rats exhibited adaptive responses that were characteristic of wild animals as soon as they were released; only difference was that they were less fearful of novelty than their wild counterparts - conclusion: domesticated rats' brains & capacity for responses are similar to those of their wild ancestors
Explain a study examining the effects of baseline stress levels & stress levels during vs. after a stressful experience on rats
- method: repeated the rat experiment BUT placed rats in ALL groups in a stressful restraint tube - results: found that in the non-running rats, regardless of housing conditions, stress hormones were elevated during the stress phase but then returned to baseline 2 hours later; there was NO increase of the level of stress hormone in the socially housed runners BUT the stress hormone response of the socially isolated runners was similar to that of the non-running group --> however, if the source of stress hormones (the adrenal gland on top of the kidney) was removed, the socially isolated runners had increased neurogenesis rates in response to running
Explain the Sperry's study using African clawed frogs to examine the migration of axons in the visual system
- method: severed the optic nerve & then rotated the eye 180 degrees - results: found that the cells ALL went back to the place that they used to be, causing the frog to then see everything upside down in that eye once the reconnection happened
Explain the study that assessed the correlation of the actual size or thickness of cortical areas with intelligence
- method: took fMRI & MRI scans of children at various ages to track the natural trajectory of cortical development & how it varies with intellectual ability - results: plasticity of the cortical area, especially the frontal cortex area, was most important to intelligence (rather than the actual size of the cortical area) --> specifically, higher-intelligence children exhibited more change in the cortex until about 11 years old, while lower-intelligence children reached their peak cortical width a few years earlier
What are mice models used for & why? How about rat models?
- mice are often used for brain-based diseases because of their small size & lower costs - rats are often used for more complex cognitive responses because they have more complex & sophisticated behavioral responses
What are some additional important components of the innate immune system? (2)
- microglia - astrocytes
How do agonists work? (3)
- mimic neurotransmitters at the receptor site - stop the removal of neurotransmitters from the synapse - increase the production of neurotransmitters
What are some different forms of opium? (3)
- morphine - codeine - heroin
Where is movement of the feet located on the motor cortex? What about the mouth?
- movement of the feet is toward the top of the motor cortex - the mouth is on the ventral side
What are some functions of the basal ganglia? (5)
- movement regulation - learning & habit formation - attention - rewarded behaviors - emotional responses
What are some other things that the basal ganglia is important for? (3)
- muscle memories - multitasking - habit formation
What are some neurochemicals involved in neuronal development? (3)
- nerve growth factor (NGF) - brain-derived neurotrophic factor (BDNF) - cell adhesion molecules (CAMs)
What are some examples of retrograde neurotransmitters? (2)
- nitric oxide - endocannabinoids
What are some neurological differences between BTBR mice & standard mice? How do these compare to humans with ASD? (3)
- no corpus callosum - smaller hippocampus - increased # of unmyelinated axons *the last 2 might be observed in humans but more research is needed; humans with ASD sometimes do have smaller volumes of the corpus callosum
What can cause a flat response to occur on a post-synaptic cell? (2)
- nothing happens - K+ & Na+ influxes balance out, leaving a flat net result
What areas have the highest density of opiate receptors? (2)
- nucleus accumbens - the surrounding areas associated with reward functions
What are some other areas involved in face perception (besides the fusiform face area)? (2)
- occipital face area - superior temporal facial recognition area
What is a study showing transgenerational transmission? (3)
- offspring of high-licking rat mothers have lower levels of corticosterone (stress hormone) response & increased glucocorticoid receptor activity in the hippocampus, leading to more a more sensitive stress hormone system & thus a healthier stress response system - adult offspring of high-licking mothers show decreased startle responses & increased exploration of a novel environment - ^ these beneficial effects also carry over to offspring of lower-licking mothers that were fostered by high-licking mothers & this behavior was then carried over to their offspring
What is the visual information called when it is outside the CNS? How about when it is inside the CNS after hitting the optic chiasm?
- outside the CNS: optic nerve - inside the CNS: optic tract
What are some cortical areas that are involved in context perception? (3)
- parahippocampal cortex (PHC) - retrosplenial cortex - superior orbital sulcus
What is the importance of identifying the Tay-Sachs disease gene? (2)
- parents can know the probability of having a child with Tay-Sachs disease - possibility of treatments to counteract the effects of Hex-A deficiency (though none have been developed yet)
What are some approaches to further promote brain recovery following a TBI? (2)
- pharmacological therapy - behavioral therapies (ex: constraint-induced movement therapy)
What structures make up the outer ear?
- pinna - external auditory meatus (ear canal) - tympanic membrane (ear drum)
What behavioral patterns are associated with the abnormal brain structure of chronic methamphetamine abuse? (3)
- positive relationship between striatal dopamine receptor availability & impulsiveness - impaired response inhibition - impaired decision making
What are some findings that demonstrate the connection between oligodendrocytes & major depression? (2)
- post mortem exams of the temporal lobes of brains from patients with major depression show reduced gene expression related to oligodendrocyte function - myelin loss is one of the most dramatic brain abnormalities in patients with major depression
What are some studies demonstrating future events (experiential context)? (3)
- preparation for hibernation is triggered by a drop in the outdoor temperature - study found that patients who are provided with procedural & sensory info in preparation for a procedure report feeling less pain during it than those who are blind to expectations - study found less activity in the hippocampus if the level of thermal pain was predictable than if participants were uncertain about the degree of pain they might experience at different times
What are some benefits of exercise, in regards to the brain? (2)
- prevents cognitive decline - increases intelligence
What is a pro of the Golgi stain? What is a con?
- pro: useful in viewing the characteristics of a single neuron - con: did NOT allow researchers to see complete neural networks
What are the functions of the parasympathetic nervous system? (9)
- pupils constrict & tear glands are stimulated - increased salivation - reduced heart rate - constricted bronchi - increased gastric secretion & movement - active pancreas - increased intestinal movement - bladder contracts - produces erection
What are the functions of the sympathetic nervous system? (9)
- pupils dilate - reduced salivation - increased heart rate - bronchi dilate - reduced gastric secretion & movement - inhibited pancreas & adrenal gland - reduced intestinal movement - relaxed bladder - produces ejaculation
What are some other brain changes in meth abusers (in addition to alterations in the dopamine system)? (3)
- reduced gray matter in limbic structures (ex: cingulate cortex) - hypertrophy (enlargement) of white matter - reduced hippocampal volumes
What are some of progesterone's functions that are relevant to neural growth? (4)
- reduces swelling in the brain - promotes expression of neural growth factors - protects neurons that surround the site of damaged tissue from eventual death - enhances myelination of neural growth factors
What do the vermis & lateral cerebellar hemispheres do? (2)
- regulate muscle tone - contain the deep nuclei (ex: dentate nucleus) that communicate in a structured, map-like fashion with the various motor & nonmotor areas of the cerebral cortex
What are some key characteristics of the corticorubro spinal tract? (3)
- runs in the *dorsolateral* part of the spinal cord - bias for *forelimbs* - bias for *flexors*
What are some key characteristics of the vestibulospinal tract? (2)
- runs in the *ventromedial* part of the spinal cord - bias for *extensors*
What are some key characteristics of the reticulospinal tract? (2)
- runs in the *ventromedial* part of the spinal cord - bias for *flexors*
What are some key characteristics of the tectospinal tract? (3)
- runs in the *ventromedial* part of the spinal cord - bias for *flexors* - primarily goes to the *shoulders & upper body*
What are some key characteristics of the corticospinal tract? (3)
- runs up & down in the *dorsolateral* part of the spinal cord - preferential bias to innervate our *forelimbs* - specific bias to *flexors*
What are some studies demonstrating internal conditions (environmental context)? (2)
- study found that mice who had been fed probiotics exhibited reduced levels of anxiety & stress hormones - rabies virus travels to areas of the brain involved in aggression --> virus spreads by exploiting the brain's function to make infected animals more aggressive & likely to attack another animal
What are some studies demonstrating external conditions (environmental context)? (2)
- study found that rats placed in "Rat Park" (a large, enriched environment with multiple rats) chose water over morphine, even when they had previously chosen morphine in the sparse, standard lab cage --> suggests that rats may consume psychoactive drugs to stimulate their brains in sparse environments (external condition) - carbon monoxide (external condition) can result in feeling that you are in a haunted house
What are some studies showing the effects of chronic methamphetamine use? (3)
- study found that rats that received high-dose methamphetamine injections showed a 35% decrease in dopaminergic synaptic endings - autopsied brains of human meth users showed up to 97% reduction in dopamine levels in an area of the striatum called the caudate nucleus - a PET study showed reduced availability of a specific subtype of dopamine receptor in chronic meth users
What are some studies showing the specific functions of cortical areas involved in complex movement? (3)
- study found that the SMA is activated when a person imagines themselves performing a complex motor task; BUT when a task involves more executive control, the pre-SMA is activated & when a task involves skills that are more dependent on external guidance of an image, premotor cortical areas are more activated - when learning a fast, complex skill (ex: juggling), the pre-SMA, primary motor cortex, & the DLPFC are involved & individuals are more dependent on visual perception; BUT as you become more proficient at the task, activity in these areas decrease - after the initial learning period, increased activity is observed in the premotor cortex & SMA BUT activation decreases as mechanisms involved in neuroplasticity lead to learning of the task
What are the 2 proposed mirror neuron areas in the brain?
1) area in the inferior frontal cortex containing the *posterior inferior frontal gyrus* & the *ventral premotor cortex* 2) rostal area of the *inferior parietal lobule* & the *posterior superior temporal sulcus*
What are some studies demonstrating past events (experiential context)? (3)
- study found that the degree of maternal support directed toward a preschool-aged child was positively associated with increased hippocampal volumes, esp. in non-depressed children - study found that a 3-month training in juggling led to increased gray matter in the brain &. that this gray matter expansion was related to the person's juggling skills - study found that gray matter increased after a 3-month study period for an important medical exam
What is some possible evidence that mirror neuron networks may be involved in the emergence of ASD symptoms? (2)
- study found that the more severe ASD symptoms a child had, the less activity was found in the proposed frontal mirror neuron system in the inferior frontal cortex - study found that children with ASD do not visually follow other people to the same extent as typically developing children (i.e. do not appear to distinguish between objects & people) --> this puts them at a disadvantage for strengthening mirror neuron networks
What are some of Merzenich's studies showing the reorganization capacities of the brain? (2)
- study found that when the 3rd finger on an adult owl monkey's hand was amputated, the brain map became completely restructured so that the adjoining fingers to the amputated fingers now included larger areas on the somatosensory cortex to provide more sensitivity to accommodate for the loss of the 3rd finger - study found that giving monkeys specific & controlled training in which certain fingers were stimulated led to larger cortical maps associated with the trained fingers
Where is dopamine produced? (2)
- substantia nigra - ventral tegmental area
What are areas higher up in the brain that contain the same retinotopic map that is on the retina? (3)
- superior colliculus - LGN - Broadman's area #17
What are some structures located close to brainstem auditory nuclei, which send projections to the inferior colliculus? (2)
- superior olivary nucleus - trapezoid body
What does the supplementary motor cortex consist of? (2)
- supplementary motor area (SMA) - presupplementary motor area (pre-SMA) Both are located in the dorsomedial frontal cortex in humans
What are some cortical areas involved in complex movement? (2)
- supplementary motor cortex - premotor cortex
What happens when the brain perceives a stressor in the environment? (3)
- sympathetic nervous system activates the release of adrenaline (epinephrine) from the adrenal medulla - neural messages travel to the hypothalamus, which sends *corticotropin-releasing hormone* to the pituitary gland - the pituitary gland releases *adrenocorticotropic hormone*, which travels through the blood to the adrenal gland where it triggers the release of *glucocorticoids* (stress hormones) from the adrenal cortex
What is the difference between the sympathetic & parasympathetic nervous systems, in terms of preganglionic fibers & postganglionic fibers?
- sympathetic nervous system has short preganglionic fibers & long postganglionic fibers that extend to the final organ destination - parasympathetic nervous system has long preganglionic fibers & short postganglionic fibers that extend to the final organ destination
Which tracts primarily innervate the core muscles in the back, shoulders, etc.? (3)
- tectospinal tract - vestibulospinal tract - reticulospinal tract
Why is L-dopa not a permanent treatment for Parkinson's disease? (2)
- the dopamine neurons in the substantia nigra are continuing to die away, even as L-dopa is working to produce dopamine - patients build up a tolerance for L-dopa & higher doses are associated with increased side effects
In what ways does Parkinson's disease disrupt the basal ganglia? (2)
- there is too much output from the basal ganglia, making the projections to the cortex become too inhibited, which leads to problems initiating movement - becomes hyper-responsive to peripheral input, which makes it difficult to filter through the most salient input to select among competing motor programs
How does the worm nervous system differ from the vertebrate nervous system? (2)
- tiny brain in the head region made up of 2 ganglia - nerve cord with interspersed ganglia
What are important aspects of becoming a skilled professional athlete? (2)
- trial & error (learning from one's mistakes) - reinforcement learning (being rewarded for making certain responses) ^ both are characteristic of practice sessions
What happens to radial cells after they successfully guide young neurons? (2)
- turn into astrocytes - continue to exist as radial cells by guiding new young neurons & generating young undifferentiated cells
Santiago Ramón y Cajal (2)
- used Golgi's new histological technique to view neurons, which led him to realize that the nervous system is NOT continuous - advocated for the neuron doctrine
Walther Flemming (2)
- used microscope techniques to examine the cell's nucleus & the movement of chromatin during cell division, thus revealing the cellular mechanisms of heredity - his work later led to the discovery of sex chromosomes
What protects the spinal cord? (2)
- vertebrae - meninges
What are some characteristics of the cells that make up the retina? (3)
- very compact & organized - light responsive - very easily activated
What are some examples of sensory abilities changing as we age? (3)
- vision & hearing become less acute, which leads to the sensory signals becoming more muddled & a functional downward spiral as neurons become less responsive to sensory information - decline in cognitive abilities - decrease in processing speed
What is the right hemisphere specialized for? (2)
- visual-spatial processing (ex: pointing to an object) - facial recognition
What are some examples of dendritic spines changing their shape over time? (2)
- when a rat is placed in an enriched environment, the dendritic spines appear to be flexible / plastic in response to the change in the rats' environment - dendritic spines become more dense in the hippocampal area of pregnant rats
What were the results of Flynn's experiments? (3)
- when the electrode was turned off, the cat would behave normally - when the electrode in one area of the hypothalamus was stimulated, the cat would display "affective defensive behavior" (arched back, dilated eyes, hair raised, snarling / hissing) - when the electrode in another area of the hypothalamus was stimulated, the cat would display "quiet biting attack" (would find a wall & sink down it or creep up to a toy & pounce)
What is the threshold for voltage-gated Na+ channels to open?
-55 mV
What are 5 types of glial cells?
1) astrocytes 2) microglia 3) oligodendrocytes 4) Schwann cells 5) radioglia
What are the 2 major subcortical systems?
1) basal ganglia 2) limbic system
What are 8 ways to modulate cholinergic synapses?
1) block the formation of ACh (hemicholinium) 2) promote formation of ACh (choline) 3) block the release of ACh (botulism toxin) 4) promote the release of ACh (black widow spider venom, beta bungarotoxin) 5) block ACh receptors on the postsynaptic cell (curare, alpha bungarotoxin) 6) promote ACh receptors on the postsynaptic cell (muscarine, nicotine) 7) block the breakdown of ACh (physostigmine) 8) block reuptake (catecholamine)
What are 2 divisions of the immune system?
1) innate immune system 2) acquired / adaptive immune system
What are the 3 types of cones & when are they preferentially activated?
1) blue --> 420 nm 2) green --> 534 nm 3) red --> 564 nm
What are the 2 sides of the neuron?
1) input side = picks up info 2) output side = sends info down
What are 2 important reasons to study venom / toxins?
1) can come up with an anti-venom 2) golden keys for neuroscience research, in that they are tools to be able to understand how our system works because they can act as a neurotransmitter & activate these systems in a very different way than endogenous neurotransmitters
What are the 2 types of postsynaptic receptors?
1) ionotropic receptors 2) metabotropic receptors
What are 2 key takeaways from studying the evolution of the nervous system?
1) can study other ancient vertebrate species to understand the human brain --> they have the same basic structure (i.e. 5 sections/pouches) that human brains have in very early development 2) evolution is working off the same basic blueprint
What are 3 types of muscle?
1) cardiac muscle 2) smooth muscle 3) skeletal (striatal) muscle
What are 2 classes of monoamines?
1) catecholamines 2) indolamines
What are the 3 components of the basal ganglia?
1) caudate (head & tail) 2) globus pallidus 3) putamen
What are the 3 components of the basal ganglia?
1) caudate nucleus 2) putamen 3) globus pallidus
What are the 2 major divisions of the nervous system?
1) central nervous system (CNS) 2) peripheral nervous system (PNS)
What are the 2 parts of the cerebellar hemispheres?
1) lateral cerebellar hemispheres 2) cerebellar peduncles
What are the 4 main categories of thalamic nuclei?
1) lateralgeniculate nucleus & others 2) motor regions 3) specific association nuclei 4) non-specific nuclei
What are 2 "side loops" within the motor system?
1) cerebellum 2) basal ganglia
What are 3 distinctive patterns of play that researchers often assess in lab rat pups?
1) chasing 2) dorsal contacts 3) pins
What 3 mechanisms maintain the negative resting membrane potential?
1) concentration gradient 2) electrical gradient 3) sodium-potassium pump
What are the 2 major roles of the ossicles?
1) conduct information into the oval window 2) amplify the signal
What are 5 types of tracts?
1) corticospinal tract (aka the pyramidal tract) 2) corticorubro spinal tract 3) tectospinal tract 4) vestibulospinal tract 5) reticulospinal tract
What are the 2 somatosensory pathways?
1) discriminative touch (i.e. the posterior column or the medial luminiscular pathway) 2) pain, temperature, & tickle (i.e. the lateral spinal thalamic tract)
What are 2 pathways for tactile information to travel on?
1) dorsal column-medial leminiscus pathway 2) spinothalamic (anterolateral) pathway
What are 2 parts of the refractory period?
1) absolute 2) relative
What are the 3 semicircular canals?
1) anterior semicircular duct 2) posterior semicircular duct 3) lateral semicircular duct
What are 2 kinds of dyes that you can inject into the brain to see where conversations are happening?
1) anterograde dye 2) retrograde dye
What are 3 variables that can be manipulated to prove whether the Nernst equation / model works? How could they be manipulated?
1) *voltage* - change the difference between the inside & outside electrodes 2) *sodium, potassium, or chloride outside the cell* - bathe the neuron in an extracellular fluid that has a certain level of one of these ions 3) *sodium, potassium, or chloride inside the cell* - deliver one of these ions to the cell
Explain the 4 possible situations if there is a jar of water filled with 4 small sodium (Na+) ions & 4 large chloride (Cl-) ions with a partition in the middle that only allows small things to get through
1) 4 positive sodium ions on one side & 4 negative chloride ions on the other --> huge chemical gradient & uneven electrical gradient (charge distribution) 2) 1 positive sodium ion on one side; 3 positive sodium ions & 4 negative chloride ions on the other --> large chemical gradient / imbalance still happening 3) 2 positive sodium ions on one side; 2 positive sodium ions & 4 negative chloride ions on the other --> improved chemical gradient & electrical gradient (but still not perfect) 4) 3 positive sodium ions on one side; 1 positive sodium ion & 4 negative chloride ions on the other --> very imbalanced in the opposite direction
What are 2 mechanisms of creating the epigenome?
1) DNA methylation 2) histone acetylation
What are 2 possible pathways that visual information can go down after being processed in the retina?
1) LGN --> cortex 2) superior colliculus
What are 2 major types of ganglion cells?
1) X cells / parvocellular cells 2) Y cells / magnocellular cells
What are 2 ways to cause an IPSP?
1) ligand-gated K+ channel allowing potassium to leave the cell 2) ligand-gated Cl- channel allowing chloride (which has a higher concentration on the outside of the cell) to move in
What are the 3 types of cellular layers in the LGN?
1) magnocellular layers 2) parvocellular layers 3) koniocellular layers
What are 3 major visual processing pathways after information comes out of the visual cortex?
1) magnocellular pathway 2) parvocellular pathway 3) mixed magnocellular / parvocellular pathway
What are the 3 major parts of the brainstem?
1) medulla oblongata (myencephalon) 2) the pons 3) the midbrain
What are the 3 major protection / surveillance systems for the CNS & what are their major functions?
1) meninges, skull, & spinal column --> physical defense 2) stress response --> helps guide behavior & physiological responses to danger 3) immune system --> surveys the body & brain for evidence of invasion of pathogens
What are the 2 further divisions that happen in the rhombencephalon?
1) metencephalon 2) myelencephalon
What are the 6 distinct cellular layers that make up the *neocortex*?
1) molecular layer 2) external granular layer 3) pyramidal cell layer 4) inner granular layer 5) inner pyramidal cell layer 6) fusiform layer & then white matter + axons
What are the 4 major neurotransmitter categories?
1) monoamines neurotransmitters 2) amino acid neurotransmitters 3) peptide neurotransmitters 4) other
What are the 3 types of opioid receptors?
1) mu (μ) receptors 2) delta (𝛿) receptors 3) kappa (k) receptors
What are 3 different types of neurons, in terms of their morphology?
1) multipolar neuron 2) bipolar neuron 3) unipolar neuron
What are 2 kinds of receptors that give us information about proprioception within the muscles?
1) muscle spindle organ 2) golgi tendon organ
What are the 6 major stages of neuronal development?
1) neurogenesis 2) migration 3) aggregation & differentiation 4) synaptogenesis & circuit formation 5) apoptosis 6) synapse rearrangement
What are the 2 pathways of dopamine?
1) nigrostriatal pathway 2) mesolimbic pathway
What are the 12 cranial nerves (in order)?
1) olfactory 2) optic 3) oculomotor 4) trochlear 5) trigeminal 6) abducens 7) facial 8) vestibulocochlear 9) glossopharyngeal 10) vagus 11) accessory 12) hypoglossal
What are the 6 retinal layers, from back to front?
1) outer segments 2) outer nuclear layer 3) outer plexiform layer 4) inner nuclear layer 5) inner plexiform layer 6) ganglion cell layer + then the nerve layer
What are the 4 (or 5) lobes of the cerebral cortex?
1) parietal lobe 2) occipital lobe 3) temporal lobe 4) frontal lobe 5) limbic lobe / cingulate gyrus
What are the 3 parts of the tegmentum?
1) periaqueductal gray central region 2) substantia nigra 3) red nucleus
What are 2 major categories of ASD behaviors, according to the DSM-5?
1) persistent deficits in social interaction / communication 2) restricted, repetitive patterns of behavior, interest, or activities
What are 2 defining qualities of sound vibrations?
1) pitch 2) loudness
What are the 2 challenges of the adult brain?
1) preserving essential components of established neural circuits 2) allowing the circuits to adapt to changing environmental challenges
What are 3 different ways to cut / section the brain?
1) saggital section 2) coronal section 3) horizontal section
What are the 5 tastes we can detect?
1) salty 2) sour 3) bitter 4) sweet 5) umami
What are the 3 parts of the cochlea?
1) scala vestibuli 2) scala tympani 3) scala media
What are the 2 main kinds of vestibular system receptors in the inner ear?
1) semicircular canals 2) otolith organs
What are 2 types of homunculus?
1) somatosensory homunculus 2) motor homunculus
What were Penfield's 4 important contributions?
1) stimulation in different brain areas leads to different things happening 2) these results^ are easily replicated from person to person 3) the brain processes sensory information, motor information, & lots of higher level things (ex: patients tapped into sensory memories) 4) these stimulations can elicit not only sensory & motor experiences, but also memories & emotions
What are the 2 divisions of the autonomic nervous system?
1) sympathetic nervous system 2) parasympathetic nervous system
What are 2 ways that the ossicles can amplify the signal?
1) taking sound energy from the larger eardrum to the smaller oval window requires the signal to be amplified 2) lever effect, in which the bones each "kick" each other, leading to amplification of the signal 200x
What are the 3 kinds of cells in a taste bud?
1) taste cell 2) supporting cells 3) stem cell
What are the 2 regions of the midbrain (mesencephalon)?
1) tectum ("roof") 2) tegmentum ("floor")
What are the 2 further divisions that happen in the proencephalon? (2)
1) telencephalon 2) diencephalon
What are the 2 halves of the retina?
1) temporal hemiretina 2) nasal hemiretina
What are 2 mechanisms that enable the resting membrane potential to depolarize (or hyperpolarize, in the case of inhibitory neural input)?
1) temporal summation 2) spatial summation
What are the 3 parts of the diencephalon?
1) thalamus 2) hypothalamus 3) pituitary gland
What are the 2 different contextual variables that influence animal behavior?
1) ultimate causes 2) proximal causes
What are the 3 directions that the semicircular canals allow you to detect movement in?
1) up / down 2) forward / backward 3) side to side
What are 2 types of motor neurons in the corticospinal tracts?
1) upper motor neurons 2) lower motor neurons
What are the 2 streams that extend from area V1?
1) ventral stream 2) dorsal stream
What were Flynn's 2 important contributions?
1) was able to elicit behaviors that were more than just a muscle twitch 2) showed that stimulating different places in the brain (specifically the hypothalamus) results in different behaviors
What does 1 kHz equal?
1,000 Hz
Compare the number of rods in the retina to the number of cones
100 million rods in the retina; 5 million cones in the retina
What is the top level of hearing by the time people are in their teens / early 20s?
17.5 Hz --> as you age, the range / bandwidth decreases
How much does the average adult brain weigh?
3.3 lbs
What happens in the caudal section of the medulla, in regards to motor information?
80% of fibers in the pyramidal area cross over to the contralateral side of the body, while the remaining fibers stay on the ipsilateral side
What percentage of human genes are expressed in the brain?
84%
How many neurons are in the human brain? Specifically, how many are in the telencephalon, the cerebellum, & the brainstem, respectively?
86 billion neurons in total - 12-15 billion in the telencephalon - 70 billion in the cerebellum - fewer than 1 billion in the brainstem
What cranial nerve is the auditory nerve part of?
8th cranial nerve
What technique does Daniel Kish use to "see", despite having no eyes?
A "flash sonar" technique that resembles sound localization techniques used by bats & dolphins
What do the large majority of electrical disturbances move through?
A graded potential Ex: if you put a stimulator into a wall, there will be a little electrical disturbance that will move in all directions before eventually dissipating (which would happen relatively quickly because a wall doesn't conduct electricity very well)
Acquired / adaptive immune system
A 2nd component of the immune system that allows immune cells to adapt to unfamiliar threats (ex: viruses, bacteria, & other dangerous substances)
Meninges
A 3-layer structure stretched across the tissue to cover the outside of the brain & the spinal cord's fragile tissue
Astigmatism
A condition where the corneal surface is NOT completely round or smooth (i.e. has bumps or pockets), which can cause the light to be imperfectly focused on the back of the retina, leading to lines of different orientations not being cleanly activated
Stem cell
A basal neuron that retains the ability to make more cells if needed
Insular cortex / insula
A brain area that provides representations of the "state of the body" to other relevant brain areas by integrating input both from within the body & from the external environment; plays a role in interoception
Locus coeruleus
A brainstem area involved in arousal
Catecholamines
A class of monoamines consisting of dopamine, norepinephrine, & epinephrine
Cresyl violet stain
A common histological method for staining neuron cell bodies
Relative refractory period
A greater change in membrane potential than usual is required to trigger an action potential
Static apnea
A discipline involving remaining still & holding one's breath underwater for as long as possible
Autism spectrum disorder (ASD)
A disorder characterized by disruptions in social interactions / communications & the presence of repetitive behaviors
Parkinson's disease
A disorder of the CNS in which patients preferentially lose dopaminergic neurons, which are primarily located in the substantia nigra
How quickly does the nervous system begin to divide into 5 large sections?
A few weeks after conception
Psychopharmacology
A field that aims to identify specific drugs that interact with the nervous system to alter behavior that has been disrupted by disease, injury, or environmental factors
Behavioral phenotyping
A form of behavioral profiling to determine whether a new mouse strain is a "match" for the human disorder of interest
Dorsal contacts
A form of play in which one animal climbs onto another's back
Pins
A form of play in which one animal flips another onto its back & pounces on top of its belly
Apoptosis
A form of programmed cell death; eliminates neurons that are deemed unnecessary during circuit formation
Betz cells
A form of pyramidal cells involved in the primary motor cortex; located in layer V of the primary cortex
Huntington's disease
A genetic disorder that causes the death of cells in certain brain areas, leading to uncontrollable movements
Skin conductance response (SCR)
A heightened emotional response characterized by increased electrodermal activity in the palms of subjects (ex: sweaty palms)
Spinal foramen
A hole in the bone; taken collectively, all of the spinal foramens stacked on top of each other line up to create a hole that the spine can run through
Vitreous humor
A jellylike substance, consisting mostly of water with specific amounts of salt, sugar, & proteins, that fills the internal cavity of the eye; keeps the eye in its spherical shape
Cerebral cortex
A large mass of brain tissue that surrounds the basal ganglia & the limbic system; also known as the "gray matter" because it contains dense collections of neuronal cell bodies & blood vessels
Cerebellum
A large neural structure that regulates motor coordination (esp. discrete motor movement) & balance; also implicated in nonmotor functions such as attention, learning, & executive control
Afterimage
A lingering but altered visual perception in the absence of the actual stimulus Ex: if you stare at something that is bright red for a long time & then look away to a blank wall, you will see a green version of it
Subdural hematoma
A localized blood clot
Bromodeoxyuridine (BrdU)
A marker of cell division in the CNS; used as a marker of neurogenesis in behavioral neuroscience research
DNA methylation
A mechanism in which genes can be modified by the addition of a methyl chemical compound to the cytosine nucleotide base in DNA
Threshold
A membrane potential that must be reached to trigger an action potential; typically is about -55 mV
Model
A metaphor or simile; drawing a parallel between a complex process & something more simple
How is Penfield's technique still used today?
A net electrode is put on the head constantly updates brain activity, which is compared to a database to try to figure out where seizures are happening; NO need for open brain surgery anymore
Multiple sclerosis
A neurodegenerative, demyelinating disease that impairs the ability of the brain & spinal cord neurons to communicate effectively with each other; neurons that go over long distances to more peripheral parts of the body are demyelinated
Enkaphalin
A peptide that activates opioid receptors
Neuroethological approach
A scientific approach that considers the role of brain structures in several species with various environmental landscapes & behavioral repertoires
Motor end plate
A section of the extrafusal muscle fiber; an area that is highly excitable & appropriate for the initiation of action potentials
Sham lesion
A placebo procedure that involves prepping the animal for surgery without actually damaging the tissue
Nestin
A protein that contributes to the formation of thin strands of proteins called microfilaments that make up the cell's infrastructure
Muscimol
A psychoactive chemical compound present in certain kinds of mushrooms; serves as a GABA agonist
Mutation
A random but permanent alteration that suddenly occurs in the DNA sequence of a gene
Synesthesia
A rare condition in which stimulation of one sense triggers additional, seemingly unrelated perceptual experiences
LSD
A semisynthetic product of a natural substance called lysergic acid, which is extracted from a rye fungus; works on the serotonin receptor to cause hallucinations (similar to psilocybin mushrooms)
Progesterone
A sex hormone present at much higher levels in females than males; maintains neural processes that are important for fetal neural growth & recovery from TBI
Explain how Leah Krubitzer's technique to determine rats' somatotopic map works
A single-unit recording electrode is placed in cortical layer 4 of a rat's brain, after which a researcher runs a paintbrush over the skin to stimulate the rat's body --> when stimulation of a specific region of the skin triggers neural activity, the boundaries of the neuron's receptive field are determined & then marked on the rat's body
Eotaxin
A specific immune molecule involved in allergic responses (ex: asthma); associated with the cognitive decline of aging
Caffeine
A stimulant drug that is found naturally in the leaves, seeds, & fruits of several plants; most widely used psychoactive drug
Cocaine
A stimulant that combats the effects of hunger & fatigue; the active ingredient of the coca plant
Nucleus accumbens
A subcortical structure that is known for its role in reward & motivational response
Neurogastronomy
A subfield of neuroscience that looks at the idea that what we taste goes together with what we smell & our somatosensory system to give us the experience of flavor
Accessory olfactory system
A supplement to the main olfactory system; consists of the vomeronasal organ (VNO) in the nasal cavity & its projections to the accessory olfactory bulbs, which then protect to the hypothalamus & amygdala
Explain why an externally-generated tickle results in more tickle sensation
A surprise tactile stimulus can NOT be canceled out by the anterior cerebellum & the unintended event is marked with the responses that accompany tickling
Corpus callosum
A thick band of myelinated axons that connects the dorsal sections of the hemispheres; main communication pathway between the left & right side of the brain that consists of myelinated axons
Cornea
A transparent surface that covers the pupil & iris
Presynaptic facilitation
If the interactions result in increased excitation & neurotransmitter release
XBC cell
A type of bipolar cell that has a noticeably different shape than other bipolar cells
Explain how the dorsal horn & the sensory neurons work to detect information
A wave of action potentials will enter into the cell body of the sensory neuron at the dorsal root ganglion; then the axons will synapse on the dorsal horn inside the spinal cord, which will then lead this sensory info to be processed by the cells that it projects to
What disorders is amphetamine FDA-approved to treat? (2)
ADHD & narcolepsy
What type of coil is used for TMS? Why?
Figure-8 shape coil --> used because this shape minimizes the intensity & undesirable spread of the TMS current
Where are the photoreceptors located within the retina?
In the bottom layers of the retina
Efficacy
Ability to produce desired effects for a targeted condition
Pluripotent cells / stem cells
Able to become many different cell types (ex: brain cells, muscle cells, etc.)
How long does sodium influx occur for?
About 1 millisecond
How many different maps in the cerebral cortex have to do with visual information?
About 40
How many muscles do we have that control how many joints?
About 640 muscles that control 200+ joints
How does the pupil accommodate for darkness? How does it accommodate for brightness?
Accommodates for darkness by dilating to let more light in & accommodates for brightness by constricting to minimize the amount of incoming light
What neurotransmitter is released at the neuromuscular junction?
Acetylcholine (ACh)
What is the building block of neural communication?
Action potential
Posterior parietal cortex
Activated when subjects are asked to localize certain sounds
How does nicotine work?
Activates nicotinic cholinergic receptors, essentially acting as a ACh agonist
What is the function of the spinal cord, in general?
Acts as the transit system for motor neural signals --> means that when neural transmission in the spinal cord is disrupted, access to the body's muscles is also disrupted, resulting in diminished capacity or a shutdown of movement
Sensory adaptations
Adaptations that allow you to NOT consciously be aware of all sensations happening Ex: sensory adaptors adapt to the fact that you are wearing shoes so you are not constantly aware of the shoes' pressure on your feet
What is a theory for how exactly caffeine alters brain functions?
Adenosine inhibits the release of excitatory neurotransmitters SO because caffeine blocks adenosine, it may result in an overall increase in excitatory neurotransmitter release
What is the active transport system of the sodium-potassium pump fueled by?
Adenosine triphosphate (ATP) = a high-energy molecule
What is the developmental period when individuals are most susceptible to the onset of mental health disorders? Why?
Adolescence --> this is a time of large changes in the brain, during which development may go awry & predispose individuals to mental health disorders
Where is epinephrine produced?
Adrenal gland (which is on top of the kidney)
Serotonin
Affects mood regulation, sleep/wake cycles, temperature regulation, sexual activity, & aggression
Explain how the nasal system works
Air comes into the nasal cavity, where there is space for the air to circulate so the epithelial cells (located in the mucus) can pick it up; then, the molecules dissolves in the mucus & specialized cells, which have cilia on the end of the dendrite that reaches down to contact the epithelial surface in the mucus, pick up the information & send it through the cribiform plate (a bone) to cranial nerve #1
What is the most abused psychoactive drug?
Alcohol
How do cones enable us to detect color?
Allow us to distinguish differences in certain wavelengths of the electromagnetic spectrum
Phase difference (sound localization)
Allow you to detect different things at different frequencies according to differences in the waves that each ear experiences; phase detectors in the brainstem can group the fact that the waves differ between the 2 ears & use this information to decide whether sound is coming from one side of the body or the other
What is the function of gyri & sulci, collectively?
Allows for a large amount of brain tissue to fit inside the skull
What is the benefit of only 1-5% of neurons taking up the Golgi stain?
Allows for detailed study of the neuron
Fusiform face area / fusiform gyrus
Allows for humans' ability to recognize & analyze faces; important for allowing us to maintain effective social interactions
Ligand-gated K+ channel
Allows potassium to move freely, which will result in it following its concentration gradient out of the cell
What does selectively permeable to potassium (for example) mean?
Allows potassium to pass through the membrane more freely than other molecules
Ligand-gated Na+ channel
Allows sodium to move freely, which will result in it moving into the cell due to the concentration gradient & the electrical gradient
What is the purpose of having the otolith organs on BOTH the x & y planes?
Allows the calcium carbonate crystals to be on the same surface & to move to compress / deflect different hair cells depending on whether you're sitting, standing, lying down, etc.
What is the purpose of lateral inhibition?
Allows us to see sharp contrasts between edges
Discriminative touch pathway (i.e. the posterior column or the medial lumniscular pathway)
Allows you to know if someone is touching you, where, & how; recognition of shape, size, texture, etc.
What are some of the psychological effects of marijuana?
Altered sensations, increased appetite, euphoria, disinhibition, relaxation, impaired memory, impaired motor performance, cognitive impairments (leading to reduced academic performance & lack of motivation)
What types of stimuli do we particularly use top-down visual processing to interpret?
Ambiguous / complex visual cues --> these are further defined by their context & the larger visual setting
Michael Gazzaniga
American neuropsychologist who severed the corpus callosum in patients with intractable epilepsy & who had seizures starting in brain areas (loci) that could not be removed
Which category of neurotransmitters is the most abundant?
Amino acid neurotransmitters
What is an example of a pharmacological therapy for TBI?
Amphetamine can be used to activate certain brain areas
Meningitis
An inflammation of the meninges around the brain; can be dangerous because is putting pressure on the brain
Adenosine
An inhibitory neurotransmitter that plays a role in promoting sleep and suppressing arousal; the levels in the brain increase every hour an organism is awake
Superadditive neural response
An integrated response much stronger than any of its components; occurs in response to highly relevant incoming stimuli
Explain how alleles work
Animals receive 1 allele of the gene from each parent Ex: rock pocket mouse can have a coat with either a light sandy color OR a dark color --> coat color is determined by 1 allele (either the sand-fur-colored allele or the dark-fur-colored allele)
Physical vigor
An animal's ability to energetically perform complex motor or challenging acts in a repeated fashion
Planum temporale
An area of the temporal cortex that is thought to be involved in language
Myasthenia gravis
An autoimmune disorder in which the immune system attacks the nervous system, specifically postsynaptic ACh receptors in the neuromuscular junction
David Blaine
An endurance artist who practices static apnea
Thymus
An immune organ below the neck region; site of T cell maturation
Encephalization quotient (EQ)
An index determined by comparing the actual brain mass of an animal with the expected brain mass for an animal of a particular body mass based on measurements of representative mammals; measure of deviation from the expected brain mass Ex: compared to a gorilla or chimp, humans have a larger brain size for the average human body size, suggesting that humans have a higher EQ
What do the semicircular canals measure?
Angular acceleration
Field research
Animals are observed in their natural environment
Which side of the spinal cord does the pain, temperature, & tickle pathway travel?
Anterolateral side
Antigens
Any substances leading to the production of antibodies
Psychoactive drug
Anything substance that has an influence on the way that we behave or on the brain itself
All-or-none law
As long as the membrane reaches the threshold value, an action potential occurs, BUT if the membrane potential does NOT reach the threshold, NO action potential occurs; every time a neuron has an action potential, it will be the same size, shape, speed, etc. (i.e. all action potentials are identical)
When does the McGurk effect occur?
As the cross-model systems attempt to correct the disparity between auditory & visual cues
What leads to the development of more adult-like executive functioning & impulse controls?
As white matter develops throughout adolescence & early adulthood
Explain the system / organization of the frontal lobe, as you move more & more rostrally
As you move more rostrally in the frontal lobe, things get more complex *Primary motor cortex* (simple movements) --> *pre-motor cortex* (planning area; complex movements & actions) --> *dorsolateral prefrontal cortex / ventrolateral prefrontal cortex* (cognition, rule-guided behavior) --> *frontopolar cortex* (long-term goals, motivation, multitasking)
Messenger RNA (mRNA)
Assembles opposite one of the DNA strands such that its nucleotide bases are in the order that DNA prescribes
Chronic traumatic encephalopathy (CTE) (aka punch-drunk syndrome or dementia pugilistica)
Associated with memory loss, behavioral / personality changes, & speech + movement (gait) abnormalities
When is the only time that the time concept idea for sound localization occurs?
At the onset of the sound
Where are the olfactory bulbs located?
At the ventral surface of the brain, just above the olfactory epithelium
Experimental studies
Attempt to isolate the effects of the IV (ex: damage to a specific brain area) on the DV(s) (ex: brain function)
Which occurs first: axogenesis or dendrogenesis?
Axogenesis
Presynaptic terminal
Axon terminal
What brain area is responsible for movement?
Basal ganglia
How do scientists parse out smell vs. taste? When is this particularly important?
Based on the avenue that the information takes to get into the brain - particularly important when examining fish because everything is dissolved in the water
Mary Rafferty
Batholow's patient; a 30-year-old woman who had a 2 inch diameter hole in her skull caused by a cancerous ulcer
Why is additional surface area of the dendritic spines important?
Because dendrites receive information from other neurons mostly via their connections with the dendritic spines SO increasing the surface area means increasing opportunities for receiving information from other parts of the nervous system
Why is the regulation of cerebral blood flow so important?
Because even a few minutes of interrupted blood supply can result in permanent brain damage
How is the difference in where somatosensory information crosses over in the discriminative pathway vs. the pain, temperature, & tickle pathway interesting from a functional neuroanatomy POV?
Because if you get a cut in the spinal cord, you might lose touch information on the same side of the cut & lose pain information on the other side of the cut because pain information crosses over
Why is MDMA known as a "messy drug"?
Because it affects multiple neurotransmitter systems
Why is spatial summation more powerful?
Because it can be responsive to how quickly signals are coming from 1 cell, as well as to how many cells are sending signals
Why is it important to wait a few weeks before assessing the effects of a manipulation affecting neurogenesis?
Because it generally takes weeks or even months before cells are classified as mature neurons
Why is it important that the brainstem develops & matures first?
Because it is functionally important for life saving functions such as breathing, heart rate, swallowing, etc. SO it is more critical for survival than higher order processes
Why can exposure to loud sounds damage the hair cells?
Because they are very finely attuned
Explain the idea of looking at the development of the nervous system
Begin by looking at the simple foundation to then understand the more complicated & elaborate systems that occur as the brain matures
Nongenomic transmission
Behavioral transmission of maternal traits
Where is the lens located?
Behind the pupil
What was Hodgkins' & Huxley's idea?
Believed that there must be a relationship between electrical activity & the function of cells in the nervous system --> idea was to record electrical changes in the brain & if these changes had anything to do with the way the brain works, there should be electrical changes associated with different behaviors
What is an antagonist for epinephrine? What does activation of the epinephrine system result in?
Beta (β) blockers - activation can calm a person's cardiovascular responses during a stressful event
Projection neurons
Big neurons that go between structures in the brain; can span long distances
Adaptations
Biological modifications that enhance survival in varying challenging environments Ex: finches with beaks that were best adapted to successfully retrieve food were the finches most likely to survive long enough to reproduce, thus passing to their offspring the likelihood of having a similarly adaptive beak
Future events (experiential context)
Brain monitors the likelihood of future events & these anticipated events affect current biopsychological processes
Where does movement begin?
In the brain --> the brain & spinal cord coordinate the many neural components that activate movement
Thoracic nerves
Bring in info from the torso, parts of the ribcage, etc.; innervate like bands across the torso
How does saltatory conduction increase the speed of neural processing?
By allowing the action potential to jump ahead to the next node of Ranvier
How do conventional hearing aids work?
By amplifying the sound so that individuals with hearing loss can better perceive the incoming sounds
How do cochlear implants work?
By bypassing the damaged portion of the ear & stimulating the auditory nerve
How do researchers study how axons find their way to their final destination?
By finding a predictable pattern in development, destroying it, & then looking to see the underlying mechanism by which it normally works through the outcome
How do a majority of psychoactive drugs with addictive potential work?
By modifying the dopamine system
How can you tell the difference between the dorsal & ventral side of the spinal cord?
By the presence of the dorsal root ganglion
How did Helen Keller learn to interpret spoken language?
By touching a person's face & throat to detect specific movements of the throat, mouth, & face
How are motor neuron diseases often categorized? Explain the examples of Parkinson's disease & myasthenia gravis
By whether they affect the upper or lower motor neurons Ex: Parkinson's disease affects upper motor neurons, specifically cells in the basal ganglia Ex: myasthenia gravis affects lower motor neurons
What were the conclusions of the study investigating the effects of maternal exposure to indirect ("bystander") stress on prenatal neural development?
Bystander stress seems to alter the neuronal architecture in developing rats, esp. female rates, through the interaction between the external social context (stressed cage-mate) & the internal context (intrauterine environment that influences male & female development)
Blood-brain barrier
Consists of tight junctions between endothelial cells, creating a filter between the brain & its incoming blood supply; prevents certain dangerous substances from entering the brain's blood supply
How does CTE differ from AD?
CTE is a slowly progressing condition with a clear environmental cause
What type of conduction do unmyelinated axons use?
Cable conduction
What is a solution to the problem with the technique of studying the first brains that ever developed through the fossils of the earliest known vertebrates?
Can look at the shape on the inside of the skull (which is preserved) to get a feel for what the brain actually looked like Ex: can use this method to see that the fish brain looks just like what the human brain looks like early in development (i.e. same structure with the same order)
Nernst equation
Can predict the voltage anywhere based on the concentration of charges on one side of the membrane vs. the other for one particular ion on a time; any time there is a situation with a membrane & a differential distribution across the membrane of charge particles, this equation will tell you what the voltage is across that membrane if you know what the concentrations of this ion are both inside & outside
What is the substantia nigra's role in the basal ganglia "side loop"?
Can send excitatory neurotransmitter (dopamine) into the basal ganglia when a behavior is rewarding, thus helping you decide which movement to initiate --> the dopamine release signals that this activity is worth taking the inhibition off the thalamus, thus allowing it to tell the cortex to act Ex: if a rat is trained to get chocolate milk when there is a light, it will eventually associate the chocolate milk & later the light with a release of dopamine from reward pathways
Coronal section
Can still see the left & right side but you cut off the front or back
Transcranial magnetic stimulation / direct current stimulation
Can stimulate the brain without having to open up the skull
What is a more modern version of endocasts?
Can use modern neuroimaging techniques to reconstruct the skulls of early vertebrates
Complete colorblindness
Can't see any color (i.e. monochromatic vision) because do NOT have cones
Blue-yellow colorblindness
Can't tell the difference between blue & yellow because missing the blue vs. yellow opponent process cell; much more rare
Wilder Penfield
Canadian neuroscientist; stimulated areas of his epilepy patients' brains, with the goal of finding a locus for the aura & then remove it to stop seizures from happening
Autosomal dominant
Carried in one of the body genes; Huntington's disease is autosomal dominant
Dorsal column-medial leminiscus pathway
Carries tactile information through the spinal cord & medulla to the somatosensory cortex; carries information about tactile discrimination from the mechanoreceptors in the skin
Mixed nerves
Carry both sensory & motor info; bring in sensory info & send out motor info
Ventral roots of the spinal cord
Carry motor / *efferent* information
Dorsal roots of the spinal cord
Carry sensory / *afferent* information
Striatum
Caudate + putamen
Striatum
Caudate nucleus + putamen, collectively
Alcohol poisoning
Causes the individual's CNS to slow down, leading to extreme confusion / disorientation & slow / irregular breathing patterns; may result in a coma or death
Nissl stain
Cell body stain that specifically stains the endoplasmic reticulum; allows you to see regional differences
Soma
Cell body that encloses a collection of micro-structures found in all cells throughout the body
"Cyte"
Cell type
Proliferative areas
Cell-producing areas
Area V3
Cells are involved in form analysis & motion
Differentiation
Cells continue to become specialized, forming neural communities consisting of similar types of neurons
Area V4
Cells facilitate the ability to identify objects, as well as color perception
Aggregation
Cells in a geographical region aggregate (i.e. cluster together)
Area V2
Cells in this area respond to outlines or defining shapes, including illusory contours that do NOT actually exist
Endothelial cells
Cells lining body cavities & blood vessels
Subventricular zone of the lateral ventricle
Cells migrate to the olfactory bulb & differentiate into interneurons that have olfactory function
Subgranular zone of the dentate gyrus in the hippocampus
Cells play a role in learning & memory
What separates the primary somatosensory cortex & the primary motor cortex?
Central fissure
Arbor vitae
Cerebellar white matter that is in the shape of a tree; resembles the organization in the cerebral cortex
Explain the cerebellum's "side loop"
Cerebellum --> thalamus --> frontal areas (& then back to the cerebellum)
Neal Miller
Challenged the view that autonomic functions are beyond individual control through studies showing that rats could control their heart rates & dogs could control their salivation in anticipation of a water reward
Why is the autonomic nervous system further divided?
Challenges that we face (positive or negative) require substantial redistribution of energy throughout the body
Which ion has a differential distribution across the axon at rest?
Chloride (Cl-) ions
Negative plastic changes
Changes that occur as the signal-to-noise ratio discerned by the brain's neurons becomes increasingly less distinct; a descriptive term for the changes associated with cognitive decline
Ligand-gated channels
Channels that open when a ligand (such as a neurotransmitter) attaches; channels involved in the process of chemicals binding to other chemicals
Ionic flux
Characterized by altered concentrations of ions, such as reduced levels of magnesium + potassium & increased levels of calcium
Alzheimer's disease (AD)
Characterized by severe memory loss & eventual loss of essential functions such as swallowing
Nicotinic cholinergic receptors
Chemical destinations for nicotine molecules; normally are activated by ACh
What are the major neurotransmitter categories based on?
Chemical structure & function
Pheremones
Chemicals that are released by one animal & detected by another; used to change the social behavior of members of their own species
Synchronized dance therapy
Children with ASD are taught to anticipate the moves of their dance partners; the goal is to stimulate & restore the proposed mirror neuron functions
Limbic system
Consists of a collection of structures that surround the thalamus that are involved in emotional regulation by indirectly influencing neurophysiological & behavioral mechanisms
What family of disorders is Huntington's disease part of?
Choreas
What is CSF produced by?
Choroid plexus
What does the Nernst equation predict the resting voltage for chloride (Cl-) is?
Cl- = -69 mV --> right about resting membrane potential, which makes sense because chloride is freely moving when the membrane is at rest (SO can go to its predicted voltage)
Cerebrospinal fluid (CSF)
Clear fluid that provides the appropriate chemical environment for the brain's cells, buoyancy & physical space that acts as a buffer when the brain is jolted due to sudden movement, & a drainage system for waste products
What is the biological mechanism behind the cerebellum's involvement in muscle memory?
Climbing fibers
Glomeruli
Clusters of axonal & dendritic processes; humans have about 10,000 of them
What are seizures caused by, in general?
Clusters of neurons becoming hyperexcitable & easily enticed to discharge abnormally
Explain the pathway of auditory information once it reaches the cochlea (7)
Cochlea --> 8th cranial nerve --> pons brainstem area (brainstem auditory nuclei) --> inferior colliculus --> medial geniculate nucleus (MGN) in the thalamus --> primary auditory cortex --> secondary, tertiary, etc. cortices
Basal ganglia
Collection of nuclei that surround the thalamus & are critical for the regulation of movement; involved in monitoring & organizing motor movements
What may play a role in color constancy?
Color-sensitive cells in area V4
_________________ organization in the cerebral cortex
Columnar / modular
What type of organization is found in the visual cortex?
Columnar organization
Explain how the retina is a map of light in 3D space & how this translates to columnar organization in the visual system
Columns are inhibited on the right & left BUT also the front & back of a column that is being activated --> can think about a circle in which the center column is excited & the outside is inhibited (or vice versa--they just have to be the opposite!)
How does amphetamine work?
Indirect catecholamine agonist that blocks catecholamine reuptake & enhances its release from the presynaptic neurons
Multisensory neurons
Contain several receptive fields for different sensory modalities; individual cells that respond to multiple senses
Purkinje cells
Contain very extensively branched dendritic trees (most ornate neurons in the nervous system!); stacked in rows that look like plates & receive inputs about the state of every single muscle
Tectum
Contains 2 sets of nuclei (superior colliculi & inferior colliculi) that are related to sensory processing
________________ between species in terms of brain organization
Continuity Ex: could use Fritsch & Heitzig's technique of stimulating the cortices of dogs on many different species (ex: fish) & get the same types of responses
Dorsal stream
Contributes information about the location of particular objects; "where" stream that expands upon the magnocellular layers of the LGN
How is the cerebellum involved in the transformation of an athlete from novice to expert?
Contributes to *sense of timing* that is critical for sports performance
Vestibular nucleus
Controls information about where the body is in space
Autonomic nervous system
Controls involuntary functions (ex: heart rate, digestion); automatic & unconscious
Iris
Controls the size of the pupil
Skin-related sensory systems
Convey messages to the brain about pressure, temperature, & pain
What do the 3 components of the basal ganglia do?
Coordinate with the cerebellum to regulate movement
Explain the basal ganglia's "side loop" to process motor activity
Cortex --> caudate / putamen --> globus pallidus --> thalamus (& then back up to the cortex)
What is a potential function of weakening receptors / synapses?
Could be a way to make the system more efficient & function better
What is the primary pathway for nasal information into the brain?
Cranial nerve #1 --> ipsilateral olfactory bulb, where there is a 1st synapse at the *glomeruli* --> many different places in the brain through *collaterals*
What is the sensory ganglia?
Cranial nerves 7, 9, & 10
The spinal nerves are to the spinal cord what the _____________ ____________ are to the ____________
Cranial nerves ; brain
What did Michael Merzenich do?
Created a map of sensory receptive fields in the hand by recording from a particular area of the monkey's sensory cortex & then tapping the monkey's fingers to determine the specific nature & location of the sensory input that would stimulate the neurons in the specific section of the sensory cortex
What did Ernst Haeckel do?
Created drawings that depicted the similarity of vertebrate embryos in a variety of species (ex: salamanders, chicks, & humans), which were considered supporting evidence of common descent strategies observed in nature
What is a technique that allows researchers to visualize different neurons in crowded regions?
Creating transgenic mice by inserting fluorescent protein genes from jellyfish & coral, which results in the mice producing 3 proteins that can be randomly produced to tag each neuron with a distinctive color
What is used to show that the cerebellum is densely populated with neurons?
Cresyl violet stain
What is the cause of synesthesia?
Cross-talk between sensory areas might cross a perceptual border, thus resulting in synesthesia
Mid view
Cut the brain in half & then turn one of the inside points sideways (saggital section)
Horizontal section
Cuts from the top to the bottom
What is the downside of the vertebrate neural control model?
Damage to the spinal cord & its accompanying nerves is unforgiving Ex: no working spinal nerves = no sensation or movement
Where is the cerebellum located?
Dangles off the dorsal section of the brainstem; more caudal to the pons
What is the location of the pituitary gland?
Dangling from the hypothalamus
Gemmule
Darwin's proposed unit of inheritance transmitted through sexual reproduction
Floater
Debris in the vitreous humor
What is loudness measured in?
Decibels (dB)
What happens to the electrical potential on the inside of the cell when a ligand-gated K+ channel is opened?
Decrease in the electrical potential (i.e. more negative)
Parkinson's disease
Degenerative neuromuscular disease that results from suboptimal activation of the various parts of the basal ganglia, leading to them failing to receive appropriate levels of dopamine & subsequent problems with movement
Compare dendrites & axons (3 each)
Dendrites: - big & thick - bumpy & have spines - have branches that come off at acute angles Axons: - small & fine - smooth - have collaterals that come off at right angles
What is the unique feature of dendrites?
Dendritic spines
Inner granular layer
Densely grouped stellate cells; sensory info
Motor homunculus
Depicts the proportion of motor cortex areas devoted to certain body parts
What does the binding of odorant molecules to receptors on the cilia of the sensory bipolar neurons result in?
Depolarization of the olfactory neurons (i.e. olfactory transduction)
Opium
Derived from the liquid extracts of poppy plants
Mescaline
Derived from the peyote cactus; works on the norepinephrine system to cause hallucinations
Axon potential propagation
Describes how the axon potential is constantly being re-generated all the way down the axon
Cortical nistogenesis
Describes how the intricate 6-layered structures in the cerebral cortex know how to go to their final resting place
Hierarchical model of the visual system
Describes how there are increasingly smaller #s of cells as we move from the photoreceptors to the bipolar cells to the ganglion cells to the thalamus & finally to the visual cortex, thus allowing for feature extraction
Synapse
Describes the minuscule gap between neurons, specifically the space between 1 axon terminal & a dendritic spine
Sensory neurons
Detect sensory info that is coming into the body
Proprioceptors
Detect where our bodies are in space by telling us if our muscles are moving or if our tendons have stretch on them or not
Glasgow coma scale
Determines the patient's ability to speak, move, engage in a conversation, & perform other basic cognitive functions; scores at various time points can predict the possible degree of function recovery
Charles Sherrington
Developed the term "synapse"
What did Aristotle believe regarding the brain & behavior?
Did NOT believe that the brain caused behavior because a chicken can still run without their heads & some insects can live without their heads for a period of time
What did Roger Sperry do?
Did experiments on African clawed frogs to examine the migration of axons in the visual system
What happens if there is damage upstream of the cochlear nucleus? Why?
Different parts of hearing will be lost (BUT there will not be complete hearing loss) --> this is because information is crossed on the left & right side as some axons go to the same side of the brain & some go to the other side, leading to a very complex & interconnected system of auditory information
Demyelinating diseases
Diseases in which there is a problem with myelinating axons
Innate immune system
Dispatches cells such as *phagocytes* & *macrophages*, which indiscriminately engulf & digest pathogens
Compare activation of the DLPFC during adolescence vs. adulthood
During adolescence, activation of the DLPFC is increased compared with adult activation --> suggests that teens can match adult performance by exerting more brain effort in this area
Stimulants (5)
Drugs that facilitate arousal & alertness; include amphetamine, cocaine, caffeine, nicotine, MDMA, novocaine
Agonists
Drugs that mimic or enhance the effects of specific neurotransmitters
Depressants (3)
Drugs that suppress arousal & increase relaxation; include alcohol, barbiturates, & benzodiazepines (Valium, rohypnol)
Dale's law
Each neuron releases a single kind of neurotransmitter at each of its terminals Ex: serotonergic neurons only release serotonin, dopaminergic neurons only release dopamine, cholinergic neurons only release ACh
Explain the complexity of the olfactory system in regards to sensory neurons & receptors
Each sensory neuron expresses the gene for only 1 receptor BUT each receptor can detect multiple odorants
Tympanic membrane
Ear drum; receives sound pressure, which causes the eardrum to vibrate at the specific frequency of the waves coming in
Amygdala
Involved in memory & emotion, particularly fear & aggression; also involved in fast processing of some sensory info
Explain the development of social-focused neural networks in young rhesus macaque monkeys
Early imitation of their mothers works to tune infant macaque's attention & behavior toward caregivers BUT this imitative behavior declines after the first few weeks
Clinical efficacy
Effectiveness
What do motor responses require to contract a muscle?
Efferent (motor) nerve
Mesencephalon
Middle portion of the developing nervous system; midbrain
Sympathetic nervous system
Employs the fight-or-flight response to prepare the body for strenuous physical responses to life's threats & challenges; increases arousal & ability to react quickly
Temporal summation
Enables the sub-threshold changes to build on themselves (i.e. summate) to action potential threshold (or away from it); involves rapid firing of presynaptic neurons that build on graded potentials to depolarize toward the action potential threshold (or away from it)
Dorsal root
Enters into the top of the spinal cord
Where does information in the discriminative touch pathway travel?
Enters through the dorsal root ganglia in the spinal cord & then travels ipsilaterally to the brainstem area, where it crosses over to then go to the thalamus & somatosensory cortex in the parietal lobe
Where does information in the pain, temperature, & tickle pathway travel?
Enters through the dorsal root ganglia where it immediately synapses on the contralateral side of the spinal cord to then travel up to the thalamus
What are some of the psychological effects of cocaine?
Euphoria, sense of increased energy, heightened mental alertness, feelings of competence & power
How often are taste cells regenerated?
Every 10 days
Visual field
Everything on the left vs. the right in the world around you (NOT everything you can see with your left eye vs. everything you can see with your right eye)
What is the function of the amygdala, piriform cortex, & entorhinal cortex in olfaction?
Evolutionary ancient structures that serve as portals to other structures of the limbic system
Center surround organization
Excitatory-center-inhibitory-surround receptive field; refers to how the cell with the light shining directly on it will be excited, while its neighbors will be inhibited (or vice versa!)
Black & tan brachyuric (BTBR) mouse strain
Exhibits diminished / compromised reciprocal social interactions, delayed approaches to mouse peers, reduced evidence of social communication, & repetitive self-grooming
Cranial nerves
Exit various areas of the brain & extend to target destinations in the head, face, & shoulder region; work to bring sensory info into & motor into out of the head
How is BrdU used in behavioral neuroscience research?
Expose animals to BrdU, commonly through injections in the abdominal area (but also can be through drinking water or injection into the ventricles), in order to measure neurogenesis
Growth cone
Extends from the cell bodies to help the cell find its way
What makes the vagus nerve different from other cranial nerves?
Extends to the body's internal organs
What allows for continual adjustment of movement patterns?
Extensive connections between the cerebellum & basal ganglia
What has allowed for knowledge about specialized sensory cortical areas?
Extensive work in which scientists have used electrophysiological recordings to systematically map the location of primary & secondary areas in the cortex
What does the pina focus sound information on?
External auditory meatus (the ear canal)
Parvocellular pathway
Extracts fine detail / foveal information; moves into the temporal lobe, where complex shape analysis occurs
Mixed magnocellular / parvocellular pathway
Extracts information about color & brightness; goes into the posterior inferior temporal cortex
Magnocellular pathway
Extracts information about movement; information goes to the posterior parietal cortex (the brain area where movement is perceived) & then starts to go to brain areas where you might start to plan your response to that movement
What do bats use to determine the position & distance of an insect from the bat?
FM-FM neurons
What is the pathway of taste information? (4)
Facial & glossopharyngeal nerves take the info to the brain --> nucleus of the solitary tract --> thalamus --> cortical insula area
What is the major function of multisensory integration?
Facilitates the timely detection of relevant stimuli in our environment
What is the frequency limit for the phase difference idea of sound localization?
Fairly low frequencies (up to about 1,500 Hz)
What is the purpose of the 3 major visual processing pathways after information comes out of the visual cortex?
Feature extraction
When did photoreceptors first evolve? Examples? (2)
First evolved about 600 million years ago in single-cell organisms (ex: algae, bacteria) - sea squirts & hagfish had an "eye patch" (rudimentary form of an eye) - the lamprey had the 1st structure that resembles our eyes about 530 million years ago
What was a study showing the potential presence of mirror neurons in macaque monkeys?
Found that certain neurons were active BOTH when the monkey was engaging in an activity & when the monkey observed another animal do the same action
What is a study showing the connection between olfaction & emotions? What was the major conclusion?
Found that children of women who used alcohol to counter negative emotional states ("escape drinkers") found the smell of beer & other alcoholic beverages more aversive than did age-matched children of mothers who did NOT use alcohol in this way (control group) Conclusion: children's associations of alcohol with their mothers' distraught emotions influenced their individual preferences for other odors encountered in their lives
Explain the Iowa Gambling Task study results
Found that patients with frontal lobe damage never showed anticipatory SCRs or adopted a strategy of bypassing the risk A+B decks for the higher payoff C+D decks, both of which the neurotypical participants DID do
What is a study showing increased automaticity among pro golfers?
Found that when asked to prepare to make a shot while in an fMRI, expert golfers exhibited increased activation in the parietal cortex, lateral pre-motor cortex, & occipital lobes, while novice golfers had increased activation in the limbic areas & basal ganglia
What did Pfrieger & Barres discover regarding astrocytes?
Found that when neurons were cultured without astrocytes or only with oligodendrocytes, they had low levels of synaptic activity, despite having the requisite axons, dendrites, & membrane excitability --> synaptic activity only increased when they were cultured with astrocytes
What did Fritsch & Hitzig do?
Found that when they stimulated certain areas (which were generally in the front of the dogs' brains), the dogs produced specific movements; specifically stimulated upper motor neurons
Lateral view
From the side
Proencephalon
Front portion of the developing nervous system; forebrain
What is a critical factor in distinguishing the human brain from the brains of other mammals?
Frontal lobe
Which lobe contains the *primary motor cortex*?
Frontal lobe
Supporting cells
Function somewhat like glial cells in the brain
Without ____________ ______________, neurons will be pruned / paired back
Functional experience
The visual system is wired on the basis of ______________ _______________. What does this mean?
Functional information - means that if you have light activity coming into a particular region, those synapses will be strengthened; BUT if this light activity does not come in, then the brain will not wire up correctly
Fusiform layer
Fusiform cells
Y cells / magnocellular cells
Ganglion cells that are involved in detecting movement; found outside of the fovea in the periphery of the eye
X cells / parvocellular cells
Ganglion cells that are involved in fine detail; found on the fovea of the retina
What led to the discovery of lateralization?
Gazzinga & Sperry's work with split-brain patients
What happened when the visual cortex is lesioned?
Parts of the LGN in the thalamus degenerate because they don't have any targets to give their info to
Transgenerational transmission
Genetic trends influenced by life events of a single generation that can extend beyond an individual's lifetime across several generations
Transgenic
Genetically modified by inserting genetic material from another organism
Mouse knockout models
Genetically modified stem cells are strategically injected into pregnant females to generate a desired mutant strain of mice
Fast & slow twitch muscle fibers are _____________ _______________
Genetically regulated
Fritsch & Hitzig
German medical students / scientists; discovered some of the electrical properties of the brain by stimulating dogs' brains with electricity through portable batteries
What animal did Hodgkins & Huxley work with? Why?
Giant squid - have a very large axon, which made it easier to get electrodes in & around it
Exteroreceptors
Give you information about what's happening on the outside / external surface of the body
Radial cells
Glial cells that provide a pathway that developing neurons follow to their destinations
What is GABA derived from?
Glutamate
What is the avenue that odorants take to go into the brain?
Go in through cranial nerve #1 to the frontal lobe / telencephalon
What is the avenue that taste information takes to go into the brain?
Go in through cranial nerves #7, 9, & 10 to areas further back in the brain
What is an alternate way of passing the signal through myelin?
Graded potentials (which move much faster than action potentials)
Explain the organization of white & gray matter in the cerebral cortex
Gray matter (cell bodies) are on the outside & white matter (myelinated axons) are on the inside / center
What is the organization of the arbor vitae, in terms of white & gray matter?
Gray matter on the outside, white matter on the inside
What color is represented by the medium wavelengths?
Green
Split-brain patients
Had their corpus callosum surgically severed to reduce the intensity of their epileptic seizures
Muscle spindle organ
Has receptor endings extending from γ motor neurons in the spinal cord that wrap around the intrafusal muscle fiber; provide sensory feedback to the muscles by detecting excessive stretch in the muscle
Rough endoplasmic reticulum
Has ribosomes that manufacture proteins
Trichromats
Have 3 types of cones; normal color vision in humans
What is a downside of reflexes?
Have little control over these responses once they are triggered
Second messengers
Have many roles, including the opening of ion channels in the postsynaptic membrane
Nocioceptors
Have receptors for sharp & dull pain; some travel faster than others, which explains why you can have a sharp pain first & then a dull pain later (or vice versa)
T cells
Have specialized detection abilities & immediately migrate to the infected areas to kill the pathogens
Non-specific nuclei
Have very diffuse connections that are all over the cerebral cortex
Why is the mirror neuron concept for humans controversial? Example?
Human neuroimaging studies have NOT obtained findings similar to those of the single-cell recording studies conducted in monkeys Ex: fMRI study showed that humans have more brain activation in the mirror neurons areas when they observed an action associated with the intention of drinking than one with the intention of cleaning
What is the lateral hypothalamus involved in?
Hunger motivation (increases eating when stimulated, decreases eating when lesioned)
What is the goal of severing the corpus callosum (i.e. the saggital cut)?
Idea is to keep the seizure localized to only 1 side of the brain so it doesn't spread
Give an example of how opponent-process theory might work
If a blue cell sends glutamate (excitatory) to the blue vs. yellow opponent process cell & the yellow cell sends GABA (inhibitory), the opponent process cell will weigh the glutamate vs. GABA --> if it gets lots of stimulation from the blue cell, it might fire, leading to you seeing blue; BUT if it doesn't have much stimulation because more input is coming from the GABAergic yellow cell, it might NOT fire, leading to you seeing yellow
Presynaptic inhibition
If the interactions result in decreased neurotransmitter release
According to the loudness idea of sound localization, how can you tell whether you are orienting in the correct direction?
If the loudness of the sound in both ears becomes more similar
When is it helpful for some neurons to be able to release multiple kinds of neurotransmitters? Example?
If the vesicle has both ionotropic & metabotropic neurotransmitters, they can do both fast-acting effects & long-acting effects, thus allowing for a longer-lasting message Ex: for learning & memory, you want to activate them in a fast way AND change them in a way that allows you to bias the way that the post-synaptic neuron thinks or reacts in the future
Explain the representation of receptive fields in the homunculus / primary motor cortex
If there is a lot of sensation in a particular area, the receptive fields will be smaller & you can pack more neuronal input into that body part --> this leads to larger representation in the somatosensory cortex because each receptive field still needs a specific amount of room to process
Huntington gene
If you have the mutant version of this gene, then you will have Huntington's disease
Frequency theory
If you record from any of the hair cells in the organ of corti while playing a particular frequency, the cells will fire with that exact same frequency (i.e. input frequency = output frequency of an individual receptor)
What did Hubel & Wiesel do?
Implanted microelectrodes in the V1 of cats while exposing them to visual scenes & stimuli, which led to them discovering specialized types of V1 neurons; after not achieving many results using an ophthalmoscope to shine light in the back of the eye, they ended up accidentally recording activity while changing out the size of a light & a line of light moved across the eye, leading to their discovery regarding how the visual system works
Olfactory bulb
Important for bringing in sensory info about what we smell
Inferior colliculi
Important for processing & localizing auditory information
Superior colliculi
Important for processing visual information
Tau (τ) protein
Important in supporting the microtubules that form the infrastructure of the neuron; abnormalities are associated with AD
What direction in the retina do horizontal cells & amacrine cells process information?
In a lateral direction
How do muscles work?
In pairs - for each muscle that contracts a joint, there will be a muscle that extends the joint
Where are cortical neurons generated?
In proliferative areas, specifically in the ventricular & subventricular zones that are located near the lateral ventricles
Where is the arbor vitae located?
In the cerebellar forest
Where is the insular cortex / insula located?
In the cerebral cortex
Where are the cell bodies for all the sensory modalities in the somatosensory system located?
In the dorsal root ganglia of the spinal cord
Where are most neurons formed?
In the fluid-filled portion of the neural tube, which is where the dividing cells are
Where do the spinal nerves exist in the spinal column?
In the junction between each vertebrae
What happens to the electrical potential on the inside of the cell when a ligand-gated Na+ channel is opened?
Increase in the electrical potential (i.e. more positive)
What is characteristic of the transformation of an athlete from novice to expert?
Increased automaticity of movement, which requires less cortical input
What happens to levels of growth factors in the brain during play? What does this suggest?
Increased levels of growth factors, which suggests that play is an enriching & stimulating climate for the developing brain
Acetylcholine (ACh)
Involved in motor functions & parasympathetic functions outside of the CNS, & in memory & cognitive functions inside the CNS; first neurotransmitter to be discovered
Explain how the ventral horn & the motor neurons work to make something move
Info comes down the white matter & will synapse on a cell in the gray matter of the ventral horn; then an action potential will go out of the spinal nerve to the neuromuscular junction, where ACh will be released, causing the muscle to contract
In what way is the motor system like a funnel?
Information can be coming down from the brain in many different ways from many different brain areas to try to control movement BUT the only way to make a muscle move is through the motor neuron in the ventral horn
Explain how information from the left visual field vs. the right visual field enters the eye
Information from the left visual field will go into the nasal hemiretina of the close eye & the temporal hemiretina of the farther away eye and then ALL of this information will be processed in the right hemisphere of the brain; information from the right visual field will go into the nasal hemiretina of the close eye & the temporal hemiretina of the farther away eye and then ALL of this information will be processed in the left hemisphere of the brain
Vestibulospinal tract
Information travels from the vestibular nucleus to the spinal cord Ex: used if someone pushes you from the side so you can get back to being balanced & keep from falling
Are there large anatomical differences between the left & right hemispheres?
Initially, research suggested that the volume of certain brain structures involved in language (ex: planum temporale) were consistently larger in the left hemisphere BUT more sophisticated neuroimaging techniques have shown fewer anatomical differences
Intracellular space
Inside the neuron
What brain area may facilitate the shift to voluntary control of autonomic functions?
Insular cortex / insula
Frontal lobe
Involved in movement & in higher executive functions (ex: reasoning, decision making) by integrating the functions of many different brain areas to complete complex tasks
Dopamine
Involved in movement, reward systems, & increased vigilance
We use all of our brain all the time; it's about the _______________ between the brain sides that is important
Interconnections
What happens once sensory information arrives in the grey matter of the spinal cord from the dorsal root?
Interneurons connect the information to the appropriate α motor neurons in the ventral horn of the gray matter
Perception
Interpreting sensory information
Koniocellular layers
Interspersed throughout the LGN, falling below each parvocellular & magnocellular layer; associated with color perception
Nissl
Invented the Nissl stain
Pfrieger & Barres
Investigated the specific role of astrocytes at the synapse through working with neurons in the eye's retina
Hemiballism
Involuntary movement that looks like someone is throwing a ball
Superior colliculus
Involved in eye movements & visual orientation, in addition to multisensory integration
Temporal lobe
Involved in hearing, language, visual processing, & emotional processing
Norepinephrine (noradrenaline)
Involved in increased vigilance, focused attention, & enhanced energy
Motor neurons
Involved in initiating movement via appropriate interneurons
Parietal lobe
Involved in interpreting sensory info
Midbrain's superior colliculus
Involved in orienting you to stimuli by focusing on what you need to look at; interprets information from multiple sources (ex: somatosensory, auditory, visual) to arrive at the most informed interpretation of a particular external event
Endorphins
Involved in pain & reward processes; peptide hormone that can act as a neurotransmitter; endogenous morphine
Periaqueductal gray central region
Involved in pain sensation
Pre-motor cortex
Involved in planning motor actions; part of a bunch of supplementary motor areas in the frontal lobe
Vasopressin
Involved in regulation of specific fluids & social relationships, along with oxytocin
Oxytocin
Involved in regulation of specific fluids & social relationships, along with vasopressin
Lateralgeniculate nucleus & others
Involved in sensory processing
Occipital lobe
Involved in visual processing
Pineal gland
Involved with circadian rhythms & cycles our body has
Pruning
Involves removing unnecessary cells so that neuronal processes attached to now-degenerated cells must find new cells with which to form synapses
Isotropic fractionation
Involves transforming the cells into a uniform fluid so that they are equally distributed & the cell nuclei can be counted
What is the major difference between ionotropic receptors & metabotropic receptors?
Ionotropic receptors have very short acting effects (EPSP or IPSP), while metabotropic receptors have 2nd messengers, which can have a much longer effect (ex: can change the 2nd cell's resting membrane potential for 100 milliseconds or an hour or a day)
What happens when ACh is released into the neuromuscular junction?
It binds to receptors on the muscle, which will activate, causing the muscle fiber to contract & pull whatever the muscle is on --> contraction of a flexor will flex the body part, while contraction of an extensor will extend it
What can happen to the tympanic membrane if it is damaged?
It can regenerate almost perfectly
What is the advantage of MEG over EEG?
It gives a more accurate image of real-time functions of the brain because it has more sensitive temporal resolution (i.e. fewer time delays)
What is a problem with frequency theory?
It has trouble explaining higher pitched sounds --> there is an upper limit at about 200 Hz because neurons are limited in how fast they can fire due to the refractory period BUT we can hear fire frequencies than this
Where does CSF eventually end up?
It is absorbed into the brain's blood supply
What happens after visual information is processed in the LGN?
It travels in the form of *optic radiations* to the primary visual cortex (V1) / the striate cortex
Once visual information crosses over the optic chiasm, what happens?
It travels in the form of the *optic tract* to the lateral geniculate nucleus (LGN) in the thalamus
What caused the dark-fur-colored allele in the rock pocket mouse? Why did it stick around?
It was the product of mutation BUT since it had survival consequences for mice living on dark lava rock, this form of the gene won out for mice in this habitat
Where is the olfactory bulb located?
Just beneath / the ventral part of our frontal lobe
What does the Nernst equation predict the resting voltage for potassium (K+) is, if it was a freely moving ion?
K+ = -78 mV --> when hyperpolarization occurs after the action potential due to the potassium ions being able to move freely, the membrane potential is right around -78mV
What animals have the largest mammalian brain masses?
Killer & sperm whales
Substantia nigra ("black substance")
Known for its production of a neurochemical (dopamine) that is important for integrated (smoother) physical movement
Gene knockout model
Making a specific targeted gene inoperative to determine the impact on animal's functions Ex: can produce specialized animal models, like mice that have been genetically prepared to represent a variety of variables of interest related to alcoholism
Red-green colorblindness
Lack either the long (red) or the middle (green) wavelength-sensitive visual photopigments, making people human dichromats; can see all the objects in their environment in different shades of colors BUT can NOT view some subtleties in the environment that can be adaptive (ex: deciding whether a piece of meat is too raw to eat)
What might be more influential for the perception of increased risky decision making / impulsivity / sensation seeking in adolescents?
Lack of experience (NOT immature brain circuits)
What is the left hemisphere specialized for?
Language
What is a real-life example of transgenerational transmission?
Lars Bygren looked at historical agricultural records from Norrbotten, Sweden & found that individuals whose paternal grandparents had experienced 2 extremes of feast & famine lived, on average, 32 years less than those whose grandparents lived at the same time but were not exposed to the same extreme feeding conditions
How long does flaccid paralysis as a result of botulism toxin last? What makes it stop?
Last for about 3 months until the presynaptic neuron retracts the original axon terminal & then grows another one down to be able to communicate with the 2nd cell (the muscle, in this case)
How is information about edges & contrasts perceived?
Lateral inhibition
Where do most of the cells in the corticospinal tract originate in?
Layer V of the primary cortex, which contains Betz cells
Explain learning & memory, in terms of quanta
Learning & memory may be a change in the # of quanta released by the presynaptic neuron, which could then influence the postsynaptic neuron
Axon initial segment
Located about 30 micrometers down from the axon hillock
Suprachiasmatic nucleus
Located above the optic chiasm; controls circadian rhythms & sleep
Apacrine glands
Located at the base of where a hair is embedded in the skin, mostly near the sex organs & in the armpits; make body odors by secreting things up onto the skin surface
Smooth muscle
Located in internal organs (ex: stomach)
Piriform cortex
Located in the frontal lobe between the insula & the temporal lobe; 1st place that smell hits for higher information processing
Cardiac muscle
Located in the heart; has elements of both smooth muscle & skeletal muscle
Entrohinal cortex
Located in the hippocampus; its connections with the olfactory system allows smell to tap into memories (i.e. "am I smelling something I should remember to be afraid of or that is rewarding?")
Primary motor cortex
Located in the pre-central gyrus; contains a map / representation of all the muscles that need to be innervated
Ultimate causes
Long-term evolutionary causes of physical & behavioral characteristics Ex: varying beak shapes of finches, sunning behavior of black marine iguanas
Explain the idea of looking at the evolution of the nervous system
Look to understand the organization of the brains of simple animals that are evolutionarily related to humans in order to understand the more complex human brain
What did Leah Krubitzer do? What did she find?
Looked at a phylogenetic tree depicting the proportion & placement of various sensory cortical areas throughout the evolution of mammals --> found that the common ancestor's cortex appeared to be dominated by the specific sensory cortical areas (i.e. unisensory cortical areas) BUT as mammals evolved, the unisensory areas shrunk & the cortical association areas, including multisensory areas, increased
Depolarization
Making the resting membrane potential less negative; when the sodium influx occurs due to the opening of the voltage-gated Na+ channels, thus making the cell more positive
What did Brodmann do?
Made maps of the different cellular structures in the different areas of the cerebral cortex using a Nissl stain to look at cell bodies; then, characterized the 6 layers in different parts of the cortex by how thick or thin each layer is & how many cells are located in each layer Ex: certain layers might have lots of cells in area 4 but not in area 3, while another might have lots of cells in area 5 but noy in area 4
Oligodendrocytes
Make up the myelin sheath that encapsulates axons of myelinated neurons located within the CNS (brain & spinal cord); support multiple projections, each serving as 1 segment of the neurons myelin sheath
What does the removal of an acetyl group from a histone do?
Makes genes in nearby DNA less likely to be expressed
What does the addition of an acetyl group to a histone do?
Makes those genes more likely to be expressed
What is a proposed function of play?
May help animals learn about their physical & social environment
What is a potential downside to separating the senses to investigate them (i.e unisensory processing)?
May limit our ability to thoroughly understand the interconnections between the brain & behavior
What is a potential threat related to microglia?
May play a role in neurogenerative diseases if it begins to emit neurotoxins to the brain's resident cells (rather than intruding cells) Ex: destruction of a brain area that regulates a neurochemical involved in movement
Are hunches vague & unsubstantiated?
Maybe not - in certain situations, the brain is taking in info & making decisions at a faster pace than our conscious awareness can process, which may lead to hunches / "gut feelings"
Homunculus
Map of the somatosensory cortex; has differently proportioned chunks of the somatosensory cortex, in which the more sensitive regions have more representation, while the less sensitive regions have less representation
What was some empirical evidence that worked to discredit phrenology?
Marie-Jean-Pierre Flourens showed that surgically removing a "bump" associated with amorous relations in a female cat did NOT reduce the cat's interest in romantic relations
What happens if the nervous system detects excessive contraction in a muscle?
May activate the antagonist muscle
How might gap junctions play a role in seizures?
May alter the membrane potential of cortical neurons in various ways to ultimately produce cellular excitation, triggering a seizure
How is the mirror neuron system involved in the transformation of an athlete from novice to expert?
May contribute to learning from watching others OR to success in sports that require individuals to predict & work in tandem with another player's movements
Differentiation
Means that certain cells are becoming different than the cells around them; becoming more specialized
Functional magnetic resonance imaging (fMRI)
Measures brain activity by detecting changes in blood flow & oxygenation; can see which brain areas appear to be using more glucose or oxygen while a participant does a task, which might indicate that these brain areas are being used in the process of the behavior
What does mechanoreception work through?
Mechanical displacement on the surface
What processes are related to proximal causes? What questions are associated with them?
Mechanism & development; "how" questions
How do salty & sour tastes work?
Mediated by ionotropic receptors (i.e. directly activating ion channels)
How do bitter, sweet, & umami tastes work?
Mediated by metabotropic receptors (i.e. have 2nd messenger systems, specifically g-protein coupled receptors, & a ligand, which is whatever the bitter, sweet, or umami chemical is)
What specific brain area dies off in Huntington's disease?
Medium spiny neurons within the caudate / putamen (collectively, the striatum)
Cell adhesion molecules (CAMs)
Membrane proteins on the cell's surface that are attracted to certain proteins located on specific types of cells; help neurons migrate & maintain trillions of connections
Biological psychology / biopsychology
Merges relevant information from the fields of biology, neuroscience, & psychology to reveal how the brain produces behavior
Histological technique
Method to study the microscopic structure of tissues; impregnated nerve cells with a silver stain (Golgi stain) that allowed him to see the structure of the nervous system tissue
What is a study showing how BDNF is implicated in learning?
Mice that are genetically engineered to lack BDNF show that the absence of BDNF during early development is associated with hyperactivity, while later in development, it is associated with disruption of learning processes
What will happen with glial cells in the event of a brain injury?
Microglia will come in to "vacuum" up the blood & then this empty space might be filled with proliferating astrocytes
What is the smallest section of the brain?
Midbrain
Glossopharyngeal nerve
Mixed; salivation & swallowing in the throat and taste in the posterior third of the tongue & throat
Hypoglossal nerve
Mixed; sensation & movement in the tongue
Vagus nerve
Mixed; sensation in organs of chest / abdomen & movement in the organs of chest / abdomen & throat
Accessory nerve
Mixed; sensation in the neck / shoulders & movement in the neck / shoulders / head
Trigeminal nerve
Mixed; senses (touch & temp) in the face & muscles of chewing
How is crack made?
Mixing cocaine hydrochloride with baking soda
Hypothalamic-pituitary-adrenal (HPA) axis
Modules cardiovascular responses, brain activity, & other physiological systems, which facilitate escape (fight-or-flight) from the threatening situation
What are the contralateral fibers from the lateral corticospinal tract important for?
Moving distal limbs & digits
What would happen if there was damage to area V5 / medial temporal area?
Moving objects would look like still-frame pictures, rather than a seamless motion
Olfactory epithelim
Mucous membrane at the top of the nasal cavity; contains olfactory sensory neurons
Multipolar neuron
Multiple dendrites extend from the soma; most common shape of neuron in the nervous system
Spatial summation
Multiple synaptic inputs originating from different locations have a cumulative effect on depolarizing the neuron to the action potential threshold (or away from it); requires multiple presynaptic neurons each altering the membrane potential
What is perception of flavor based on?
Multisensory integration (vision + smell + taste + touch)
Which ACh receptor is metabotropic?
Muscarine (muscarinic)
Fast twitch muscle fibers
Muscle fibers that contract at a fast rate and have great strength but very little endurance; allow us to have great bursts of energy BUT do NOT last very long Ex: sprinters are thought to have more of these
Slow twitch muscle fibers
Muscle fibers that contract at a slow rate and have great endurance Ex: long distance runners are thought to have more of these
Flaccid paralysis
Muscles can NOT contract & move because they are too relaxed
Mirror neurons
Neurons in the brain that are activated when one observes another individual engage in an action and when one performs a similar action; play a role in empathy, speech perception, language comprehension, social interactions, & ASD
What is the name that Merzenich has given to the changes associated with cognitive decline?
Negative plastic changes
What approach did Paul MacLean use? What did he conclude from this?
Neuroethological approach --> led him to believe that the limbic system evolved to facilitate play behavior, parental behavior, & the cry of infants on separation from their mothers (all of which are behaviors that seemed to be new to mammals as they evolved from reptiles)
Where are ACh neurons primarily found, especially in terms of myasthenia gravis?
Neuromuscular junction
How might excessive growth of collaterals contribute to seizures?
Neurons that are too "networked" so that excessive synchronized activity occurs when the neurons are stimulated in certain ways
Interneurons
Neurons that transmit impulses between other neurons
What is the "1st messenger"?
Neurotransmitters
G protein-coupled receptors
Neurotransmitters binding to metabotropic receptors activate a series of events that indirectly open the ion channels
Explain how receptors act as a lock & key
Neurotransmitters must fit correctly to open them --> they only fit into & can act on receptors that are specific for it
Double stain
Nissl stain + Golgi stain
Are astrocytes vulnerable to the toxic effect of glutamate release that typically follows brain damage?
No
Are cochlear implants the same as conventional hearing aids?
No
Are immune cells allowed into the brain?
No
Does the size of the cortical area devoted to a certain body area relate to its size?
No - it relates to the body area's function Ex: area representing the hands & mouth require a greater area of motor cortex than the larger surface areas representing the legs & back, which suggests that the hand is one of the brain's most valued instruments for interacting with the world
Can you regain a frequency once it is lost?
No - once you lost a frequency, it tends to be gone forever
Do all dividing (proliferating) cells in the CNS become mature neurons that are integrated into functional neural circuits?
No - some will die; others will mature into glial cells or endothelial cells (migrate to the brain's vascular system)
Do the sodium-potassium pumps stop working during an action potential?
No - they continue to pump 3 sodium out & 2 potassium in to maintain the uneven distribution; also, they work to bring things back to the resting membrane potential once the action potential is over
Do the basal ganglia or cerebellum have any direct access down the spinal cord to get at the lower motor neurons / influence the final common pathway to the muscles?
No - they rely on getting information to other places in the brain
Are objects represented in rich detail in the relevant cortical areas responding to contextual cues? Why or why not?
No - this increases interpretive speed
Can the cerebellum initiate movement on its own?
No - uses internal & external feedback to monitor & modify movements as they occur
Do humans have the accessory olfactory system?
No - we only have remnants of it --> the VNO develops in human fetuses BUT then regresses over time
Are your levels of fast vs. slow twitch muscle fibers set in stone?
No - you can develop more of them based on experience (ex: practicing for a marathon)
Absolute refractory period
No amount of stimulation can trigger an action potential
Anesthesia
No awareness
Does THC directly affect dopaminergic neurons?
No because they lack cannabinoid receptors - BUT THC indirectly affects them by activating cannabinoid receptors that affect GABAergic neurons so that they no longer inhibit dopamine neurons, thus resulting in the increased release of dopamine
Principle of consistent speed
No matter the strength of the initiating stimulus, the intensity of the action potential is set & remains constant as it moves down the axon
Analgesia
No pain
Is the cerebral cortex the whole brain?
No!
Do certain areas of the tongue taste different things (ex: sour areas, sweet areas)?
No, this is a myth - we can taste ALL tastes on ALL parts of the tongue (though there may be some areas that have more of one kind of receptor concentrated there)
Is the brain necessary for the worm to move its body? Why or why not?
No- the nerve cord with interspersed ganglia allows for individual functioning in the absence of the brain
Is there only one type of papillae?
No- there are 3 basic types of papillae Ex: papillae called fungiform may have 1-5 taste cells, while another form may have hundreds of taste cells
What is some evidence in primates for the skin theory color of vision?
Non-human primates with trichromatic color vision have NO fur on their faces (so the color of the skin is visible), while those primates with dichromatic color vision have retained full facial hair
What is the advantage of CT, PET, MRI, & fMRI?
Non-invasive (i.e. do NOT require brain surgery)
What is an advantage of TMS?
Non-invasive technique ("virtual lesion") that can be used in experiments with humans
What is some evidence that implicates the cerebellum in various mental disorders?
Non-motor symptoms (ex: reduced pleasure, anxiety, repetition of responses, aggression) are also observed in psychiatric disorders, such as depression, autism, & OCD
Inhibitory postsynaptic potential (IPSP)
Occurs if the neurotransmitter-receptor binding makes the membrane potential hyperpolarized through making the membrane channels more permeable to negative ions (ex: Cl-); moves the neuron farther away from threshold, making it less likely that an action potential will be generated
Are we consciously aware of the visual deficit associated with the blind spot? Why or why not?
Not usually - when one eye is still functional, the higher cortical areas can fill in the visual gaps left by the blind spot
What did Fritsch & Hitzig find when they stimulated the back of the brain? The front of the brain? The middle of the brain?
Nothing obvious happened when they stimulated the back of the brain BUT when they stimulated the middle part of the brain, they got movement (flinching) of the dogs on the contralateral side (i.e. right stimulation led to movement in the left side, & vice versa)
What did Don Stein do?
Noticed that his female rats tended to recover faster from brain damage than male rats of the same age, which led him to explore the effects of progesterone
What does increased dopamine levels during adolescence lead to?
Novel responses in animals (ex: leaving the family for novel territories & potential mates) & humans (ex: risky behaviors like driving & sex)
Reticular formation
Nuclei & fibers that are located throughout the central area of the brainstem; maintains sufficient levels of arousal necessary for animals to direct their attention toward relevant environmental targets & is involved in sleep/wake cycles
Explain the pathway of taste information in the brain (3)
Nucleus of the solitary tract in the medulla --> taste area in the thalamus --> gustatory cortex
What did Karl Lashley do?
Observed plasticity in the brain of an adult rhesus monkey
Excitatory postsynaptic potential (EPSP)
Occurs if the neurotransmitter-receptor binding makes the membrane potential depolarized through an influx of sodium ions into the membrane; brings the neuron closer to threshold, making it more likely that an action potential will be generated
What is the only sensory stimuli that is NOT processed in the thalamus? Why?
Olfaction (smell) - this is an evolutionarily old sensory system that goes directly to relevant brain areas as it enters the brain to facilitate survival
Tectum
Orients us to stimuli in space
Radioglia
Only found prenatally during very early brain development; radioglia line a fluid-filled space by extending their processes to create a track / "highway" that baby neurons travel along after their "birth" in the fluid-filled space to reach their final destination as a mature neuron
Monosynaptic
Only one synapse
Gated ion channels
Open & close based on the environmental conditions around the membrane
Voltage-gated ion channels
Open & close in response to changes in membrane potential; when the membrane reaches a certain mV threshold, these channels open their pores in the middle, allowing things to pass through; specific to specific ions (ex: voltage-gated Na+ channel, voltage gated K+ channel)
What is a useful application of rodents' extremely sensitive sense of smell?
Operant conditioning can be used to train giant African pouch rats to detect the presence of trinitrotoluene (TNT) in land mines in Mozambique & Mycobacterium tuberculosis in human saliva --> this is more efficient than human lab assistants using visual screening techniques enhanced with chemical tests & microscopes
What did papers published in the 1950s & 1960s say about movement?
Our bodies have evolved for the primary purpose of movement (i.e. moving to find food or to escape a threat)
Pinna
Outer / external ear that allows us to hear better by cupping out to catch sound waves; involved in sound localization
Extracellular space
Outside the neuron
Peripheral nervous system (PNS)
Part of the nervous system outside the brain & spinal cord; acts as a go-between between the outside world & the CNS
Which lobe contains the *primary somatosensory cortex*?
Parietal lobe
Compare the size of the receptive fields in parvocellular ganglion cells vs. magnocellular ganglion cells
Parvocellular ganglion cells have small receptive fields, while magnocellular ganglion cells have large receptive fields
Past events (experiential context)
Past emotional, social, & cognitive experiences shape your neurobiology
Mesolimbic pathway
Pathway from the ventral tegmental area to the brain reward area (including the nucleus accumbens)
What is a problem with using L-DOPA as a treatment?
Patients become sensitized to it relatively quickly (within a year or so)
What did Gazzinga & Sperry find through their studies with split-brain patients? (2)
Patients could verbally indicate what they saw if the stimulus was presented to the right visual field BUT if it was presented to the left visual field, they could only point to the correct stimulus / answer with their left hand (could NOT verbally indicate what they saw) --> patients could respond verbally only if the left hemisphere was activated by the right visual field
What were the results of Penfield's surgery to sever the corpus callosum? Examples? (2)
Patients had problems communication from one side of the brain to the other --> if you isolate the sensory input to only one side of the brain, then the patient can only understand & communicate about the input that it sees using the opposite side of the brain Ex: the right hemisphere (which controls the left visual field) could see faces BUT the left hemisphere (which controls the right visual field) could only see contours because facial recognition is largely located in the right hemisphere Ex: if the left hand is feeling an object, the patient would not be able to name it because the information went to the right side of the brain (which doesn't contain the majority of language function)
Who gave the limbic system its name?
Paul MacLean, a neuroscientist who discovered a population of epileptic patients who reported intense feelings & emotions (rather than experiencing convulsions)
What is the threshold for voltage-gated K+ channels?
Peak positive voltage charge point (which is around +57 mV)
The different types of cones have __________ ___________ BUT also ___________ _____________
Peak sensitivity; broad tuning (i.e. can still respond, but not as robustly)
Contrast enhancement
Perceived contrast between lighter & darker bands (March bands)
What types of neurons/nerves easily regenerate? Why?
Peripheral nerves / PNS neurons --> damage to these provokes immune cells (macrophages) to clean up the debris, which results in regrowth
What have been some recent criticisms of Ernst Haeckel's work?
Photographs of actual embryos suggest that he may have miscopied or taken artistic liberties with the images Ex: embryos that are actually different sizes appear as the same size & in the same position in his drawings
What is required for transduction in the visual system?
Photopigments in the photoreceptors
What does the VNO require in order for it to work? How does this differ from the olfactory bulb?
Physical contact with the urine or other chemicals - differs from the olfactory bulb, which can be activated through volatile molecules traveling through the air
Galen
Physician to the Roman gladiators; realized that people who had head/brain injuries were sometimes different after they recovered, which gave rise to modern brain science's focus on damage to the brain caused by lesions
What is the 1st place that smell hits for higher information processing?
Piriform cortex
What do tip links have?
Places where there are ion channels
What is the role of astrocytes in the blood-brain barrier?
Play a role in maintaining the blood-brain barrier by adding an additional level of cellular defense to the barrier, especially following brain injury
Ion pumps
Play an essential role in the distribution of ions inside & outside the neuron
What percentage of an animal's daily activities is taken up by play? What percentage of daily energy expenditure does play take up?
Play consumes as much as *20%* of an animal's daily activities & up to *10%* of its daily energy expenditure
Explain the possible relationship between opportunities for children to play & the increasing prevalence of ADHD
Play-deprived children may have an increased desire to play, which adults may interpret as a form of impulse-control disorder (like ADHD)
Superior temporal sulcus
Plays a role in audiovisual & facial integrative sensory processing; activated during vocalization & audiovisual discrepancies (like the McGurk effect)
Dorsal anterior cingulate cortex (ACC)
Plays a role in disengaging from a default mode of processing present in the dorsal ACC when a person is not focusing on a specific task; also, integrates past error information as an individual monitors performance & plans future responses
Red nucleus
Plays a role in limb movement; seems to have evolved as limbs (such as arms) emerged on the larger evolutionary scene
What is a potential threat related to Schwann cells?
Plays a role in multiple sclerosis --> the death of Schwann cells that make up the myelin sheaths compromises the conduction of the nerve impulse, leading to sensory & motor impairments
Hypothalamus
Plays a role in regulating motivational systems & behaviors such as sexual behavior, aggression, parenting, hunger, thirst, stress, & more
What is the major difference between progenitor cells & pluripotent cells / stem cells?
Pluripotent / stem cells have the ability to produce pluripotent (unspecialized) cells, while progenitor cells do NOT have this ability --> can develop into various types of neural cells but can NOT differentiate into other types of cells, such as muscle or cardia cells
Ion channels
Pores in the neuronal cell membrane that allow the passage of ions; made from proteins
Parabiosis
Portions of the mice are surgically bound so that the blood supply is shared between the 2 animals
Context frames
Prepackaged visual perceptual templates that we are likely to encounter; past experience leads us to develop them Ex: very likely for a person to be holding a dog BUT NOT for a dog to be holding a person
Which side of the spinal cord does the discriminative touch pathway travel?
Posterior side
Ionotropic receptors
Postsynaptic receptors that alter the membrane potential immediately on binding to neurotransmitters; almost immediately (i.e. within a few milliseconds) open a specific type of ion channel, thereby enabling a specific type of ion to enter the postsynaptic cell
Metabotropic receptors
Postsynaptic receptors that are slower to respond to neurotransmitter release; work by releasing a 2nd messenger into the postsynaptic neuron, which can then do many actions (ex: go into the nucleus, cause the cell to function differently, turn on/off gene transcription, do different things while inside the synapse)
What ions are higher in the intracellular space?
Potassium (K+) ions
What ion is the resting membrane selectively permeable to? What is the result of this?
Potassium --> this allows K+ ions to flow through the membrane at a moderate rate through K+ ion channels BUT restricts the flow of Na+ ions through the membrane to a very low rate (because the Na+ ion channels are closed when the membrane is at rest)
What is the purpose of maintaining a negative resting membrane potential?
Prepares the neuron to fire strongly & rapidly in response to a stimulus, which is critical for survival
Are most nicotinic cholinergic receptors presynaptic or postsynaptic? What are the effects of this?
Presynaptic - this means that nicotine not only alters the release of ACh, but also alters other neurotransmitter systems in which nicotinic receptors are situated on the presynaptic terminal (i.e. can have far-reaching effects beyond the cholinergic system)
Glycine
Prevalent major inhibitory neurotransmitter in the brain stem & spinal cord; plays an important role in the control of many sensory & motor pathways
Bottom-up visual processing
Processing specific visual information in increasing levels of complexity; analysis that begins with the sensory receptors and works up to the brain's integration of sensory information Ex: firing of ganglion cells
"Flash sonar" technique
Produce clicking sounds & then uses his sharpened auditory skills to be able to hear the ever-so-slight echoes of the clicks & interpret their location
Schwann cells
Produce segments of the myelin sheath in neurons that are located in the PNS (outside of the brain & spinal cord); entire cell body is wrapped around the axon
Mitochondria
Produces energy necessary for cellular functions; responsible for converting energy from food into an energy source for our cells
Angiogenesis
Production of new blood vessels
What is a promising treatment for facilitating the remyelination of axons in MS patients?
Progesterone (reproductive hormone)
What happens when black widow spider venom or beta bungarotoxin promote the release of ACh?
Rigid paralysis --> both of these toxins stimulate the postsynaptic receptors in the muscle cell over & over again, leading to a paralyzed state
Which type of neurons develop first? Why?
Projection neurons - they need to start communicating with one another to get the whole organism coordinated so that every structure can talk to each other; then, can begin worrying about local circuitry within each structure
What type of projections have been identified as playing a crucial role in the adaptive modifications that occur during echolocation, allowing bats to capture small moving prey?
Projections from the auditory midbrain area to the pontine nuclei in the upper brainstem
Brain-derived neurotrophic factor (BDNF)
Promotes the maturation of neurons & synapse formation throughout the brain; implicated in complex behaviors (ex: learning, depression)
What did Henry Dale think about the mechanisms of synaptic transmission?
Proposed the possibility that natural chemical substances might be transported across the synapse after noticing similarities between the effects of the chemical acetylcholine & the functions of the autonomic nervous system
What are police officers assessing when using the walk-&-turn test to determine sobriety?
Proprioception
What is the major function of cones?
Provide information about color & other visual details under well-lit conditions
Analgesics (4)
Provide pain relief & altered psychological experience; include opium, morphine, codeine, heroin, (& endorphins)
Corneal epithelial cells
Provide the cornea with nutrients & take away its waste products through the tear film
Anterior commissure
Provides connections between the more ventral sections of the hemispheres
Ventral stream
Provides information about the identification of various objects; "what" stream that expands upon the parvocellular layers of the LGN
Posterior superior temporal sulcus
Provides the primary visual input to mirror neurons
What are the 3 functions of cerebrospinal fluid (CSF)?
Provides: 1) the appropriate chemical environment for the brain's cells 2) buoyancy & physical space that acts as a buffer when the brain is jolted due to sudden movement 3) a drainage system for waste products
What lines the inside & outside of the neural tube?
Radial cells
How large is the soma?
Ranges in size from 5-100 micrometers in diameter
Where is serotonin produced? What is it synthesized from?
Raphe nuclei - synthesized from the dietary amino acid tryptophan
Thermoreceptors
Receptor cells that tell you whether something is hot or cold; allow you to detect temperature in the world around you
Hierarchical synapses
Refers to the idea that some synapses are more important than others in the process of summation or integration on the 2nd cell; not all synapses are created equal--some are strong & some are weak Ex: there is a higher chance of an electrical disturbance from a closer synapse getting to the axon hillock than one that is farther away, so the closer synapse is likely more important
What does the postsynaptic neuron need to have in order for neural communication to occur?
Receptors that can bind to the released neurotransmitter
What is the benefit of the vertebrate nervous system, as it has evolved?
Redistribution of neural energy allows vertebrates to interact with the environment in more sophisticated ways
What does damage to the occipital face area or the superior temporal facial recognition area cause?
Reduces the quality of visual information about parts of the face, thus eliminating the ability to recognize individual faces
Electronic screen game-induced seizures / video-game epilepsy
Refers to how in individuals who are susceptible to seizures, environmental stimuli (ex: video games with rapidly changing patterns of light) can affect large populations of neurons in the brain in such a way as to induce a seizure
Motor system
Refers to movement & our ability to move our muscles/bodies around
Spatial summation
Refers to the addition of signals from 2 or more neurons onto a single postsynaptic neuron, thus making it more likely that the 2nd neuron will reach threshold (or not reach it)
Epileptogenesis
Refers to the transformation of a normal brain into a brain that supports seizures
Why were reflexes initially studied? What did this research reveal?
Reflexes were studied a lot about 50-80 years ago because people were trying to figure out how circuits worked / how synapses formed in circuits & they assumed that reflexes would be a simple place to start; BUT research has shown that reflexes are quite complex in terms of the things they can do & the info they can handle without our awareness Ex: if you step on something sharp, you need to have a reflex that makes you contract & pull away on one side but also extend & put your weight down on the other side, which involves the entire spinal cord
Kappa (k) receptors
Related to *dysphoria & hallucinations, pain perception, temperature control, & certain neuroendocrine functions, such as the stress response* (locations in the striatum, amygdala, hypothalamus, & pituitary gland)
Mu (μ) receptors
Related to the *analgesic effects* of opioids (locations in the thalamus, periaqueductal gray, raphe nuclei, certain areas of the spinal cord, & areas associated with reward, such as the nucleus accumbens) as well as the *cough control & anti-nausea effects* (the brainstem)
Delta (𝛿) receptors
Related to the *olfactory, motor, cognitive, & rewarding effects* (locations in the forebrain, including the striatum, olfactory areas, substantia nigra, & nucleus accumbens)
What do the otolith organs measure?
Relationship to gravity
Somatosensory system
Relays information about the body's interactions through touch, position, & movement with the external world
The pons
Rich in nerve-fiber pathways that transfer info from one side of the brain to another & to more dorsal (upper) areas; the brainstem hub for info transfer
What can cause CTE?
Repeated concussions or hits to the head
Telomeres
Repetitive DNA sequences located at the end of chromosomes that are critical for keeping our genes intact during chromosome replication
Brain stimulation techniques
Requires the same preparation as a brain lesion BUT a permanent electrode is implanted to stimulate the brain area to determine the effects of increased activation of a specific brain area on behavioral functions
What is a study showing the specificity of the visual system in the cortex?
Researchers were not making much progress recording from the visual cortex in monkeys until one of the researchers waved at the monkeys, which caused the cells in the monkey's visual cortex to fire --> led them to discover that they were recording from cells that were only designed to fire to visual stimuli in the shape of a moving hand
Complex cells
Respond to bar-shape stimuli BUT are less selective about the location of the bar in the visual field; fire to lines of particular orientations, in particular places, & that are moving in a particular direction
Simple cells
Respond to bar-shape stimuli located in specific areas in specific orientations (ex: vertical, horizontal); fires to lines of particular orientations in particular places in the visual field
Hypercomplex cells
Respond to bars of a particular length by detecting endpoints, as well as aspects of position & orientation
Free nerve endings
Respond to tissue damage & temperature changes, which we experience as pain
Specialized types of V1 neurons
Respond to very specific features of the visual stimulus
Blood-brain barrier
Restricts the entry of substances into the brain by acting as a filter & protecting the brain from potentially harmful substances; the brain's primary security system
Constraint-induced movement therapy
Restricts the use of the functional limb to encourage the use of the impaired limb
Hallucinogens (3)
Result in altered perceptual experience; include mescaline, LSD, psilocybin
Compare humans & rodents in terms of the amount of the cortex dedicated to olfaction. What does this suggest?
Rodent brain devotes a larger proportion of the cortex to olfaction - suggests that rodents rely on this sense more than humans do & would experience significant survival challenges if it was lost
Compare rods & cones (3)
Rods - achromatic (can NOT detect color) - very sensitive to light - more concentrated in the periphery of the retina; completely absent in the fovea Cones - chromatic (can detect color) - less sensitive to light - more concentrated in the fovea
Explain the general pathway of visual information from the rods & cones onward
Rods & cones synapse on the *bipolar cells* which form synapses with the *ganglion cells* which have bundles of axons emerging from them that make up the *optic nerve* that exits through the back of the eyeball
Where are rods more densely packed? How about cones?
Rods are more densely packed around the periphery of the retina, while cones are more densely packed in the center of the retina, especially the fovea
Central canal
Runs the entire length of the spinal cord & is filled with the cerebrospinal fluid
Why might oligodendrocytes play a role in major depressive disorder / major depression?
Secrete dopa decarboxylase (an enzyme) that is critical for serotonin synthesis
What is a large proportion of the cortex dedicated to in raccoons?
Sensory functions of the forepaw - creates "super-sensitivity" in this body part
Golgi tendon organ
Sensory receptor that detects excessive contraction; located in the tendons
Animals have specialized _____________ _____________ for each sensory ability
Sensory receptors
Tectorial membrane
Separates the scala vestibuli from the scala media; only attached on one side to the oval window, which allows it to move more freely
Cerebellar peduncles
Serve as a neural communication transit system to other brain areas, such as the cerebral cortex; provide opportunities for the cerebellum to play a role in cognitive functioning
What is the thalamus comprised of?
Several nuclei specialized for identifying specific types of sensory stimuli & directing them to the appropriate cortical location
What was the significance of Ader & Cohen's study?
Showed that the disciplines of immunology & neuroscience should NOT be thought of as separate, which eventually led to the establishment of psychoneuroimmunology
Which brain areas were examined in study investigating the effects of maternal exposure to indirect ("bystander") stress on prenatal neural development? (3) Why?
Sliced or sectioned the brains in areas that have previously been shown in rats to be affected by stress - medial prefrontal cortex - orbitofrontal cortex - dorsal area of the hippocampus
Synaptic vesicles
Small spheres surrounded by vesicles; contain neurotransmitters
Taste buds
Small structures of soft tissue located on the tongue, soft palate, & areas of the throat; contain taste receptors that are specialized for detecting salty, sweet, sour, bitter, & umami (rich, meaty taste)
Event-related potentials (ERPs)
Small voltages in response to a specific task or stimulus; tracking the location of ERPs in the brain can be used to provide information about the function of different brain areas
What sense may have been the most important for early mammals, driving the expansion of the mammalian brain?
Smell (olfaction)
How is smell involved in perception of flavor?
Smell interacts with taste to produce perceptions of varying flavors
Explain how behavioral tests have been used to study social anxiety, social preferences, & ASD
Social preference test (in which a mouse can choose to approach another mouse in an enclosure, approach just the enclosure, or remain alone) is used to determine whether animals are more likely to spend time with another animal or alone
What happens when nicotine binds to nicotinic cholinergic receptors?
Sodium channels open to allow the depolarization of the neuronal membrane
Aura
Something that happens when you're about to have a seizure; distinct for different people but may feel panicky, see bright lights, or smell something
Dorsal root ganglion
Something that is hanging off the spinal nerve before it actually enters the spinal cord; where the concentrated cell bodies are for sensory info coming in
Young-Hemholtz trichromatic theory of color vision
Specialized receptor cells respond specifically to short, medium, & long wavelengths of light, ultimately informing our perception of all recognized colors; essentially 3 receptors that are maximally sensitive to the perception of blue, green, & red are mixed in different ways to produce all of the colors we can see
______________ & ______________ are always related in the nervous system
Structure & function --> if they look different, they likely do something different
What evidence do we have that the insular cortex / insula may be involved in Blaine's ability to monitor & control his physiological processes?
Studies show increased activity in this area for patients who can suppress ongoing chronic pain or accurately judge the timing of their own hert beats
What is a study suggesting that nicotine addiction may be centered in the insula?
Study found that chronic smokers who had damage to the insula were able to quit smoking more easily, possibly because compromised processing may have led to decreased awareness of the uncomfortable withdrawal effects
What is a study showing the effect of outdoor play on myopia?
Study found that myopia (nearsightedness) decreased by 10% in children who had extra outdoor play added to their daily curriculum than children who did not --> outdoor play provides a richer visual landscape with distant horizons than playing in smaller indoor spaces
What is a study showing multisensory integration & cross-modal stimuli?
Study found that participants who smell an aroma while looking at a beautiful mountainous scene smelled a pleasant / fresh smell, while those who smell the SAME aroma while looking at an image of a city scene with smoke stacks emitting dark smoke smelled a toxic / pungent smell --> the visual scene contributed to the final perception / interpretation of the aroma
What is a study showing that selective impairment of mirror neuron areas specifically impairs imitative behavior?
Study found that using repetitive transcranial magnetic stimulation to cause temporary disruption specifically in the mirror neuron area resulted in disrupted imitative behavior
What is a study using BTBR mice?
Study found that, when given a choice between an enclosure with another mouse, an enclosure with an object, & an empty enclosure, control mice chose to spend more time with the other mouse, while the BTBR mice spent more time with the object
What does axon shearing lead to?
Subdural hematoma
Where are dopaminergic neurons primarily found, especially in terms of Parkinson's disease?
Substantia nigra, which is part of a bigger cluster of brain areas called the basal ganglia (responsible for movement)
What happened to Marc Baskett?
Suffered severe trauma to his brain, yet because of a hormonal intervention involving progesterone, he shows little evidence of the ordeal today
What brain area is involved in the McGurk effect?
Superior temporal sulcus
Basal cells
Supporting cells in the nasal system; actually are stem cells that are constantly turning over / being regenerated
Flocculonodular lobe
Supports fundamental motor functions such as the maintenance of balance & posture; oldest part of the cerebellum
What is one of the first brain areas affected when alcohol is consumed?
The cerebellum
Cholinergic synapses
Synapses that use ACh
What is on the presynaptic terminal?
Synaptic vesicles
Smooth endoplasmic reticulum
Synthesizes substances such as lipids & steroids
Chemical senses
Tase & olfaction; detect chemicals that are dissolved in saliva or floating in the air
What is the most ventral part of the midbrain?
Tegmentum
Interoreceptors
Tell you the state of what's going on inside your body; located deep down in your viscera / gut
Explain a test for astigmatism
Test requires people to look at 2 parallel lines in different orientations starting from far away; as they walk closer, they have to say when they can tell that there is 2 separate lines instead of 1 --> astigmatism can make people see some line orientation pairs better than others due to how the light is focused
What does variation of cone densities & distributions across animals suggest? Example?
That specific cone / rod ratios have been selected for various habitats & lifestyles Ex: BOTH rats & squirrels are dichromats BUT the diurnal squirrel's retina contains about 86% cones, whereas the nocturnal rat retina contains only 1% cones
What does the large proportion of raccoon & platypus cortex dedicated to sensory functions suggest?
That the amount of cortical territory devoted to a sensory or motor function is related to the importance of that function to the animal's survival
What is the assumption that the Nernst equation makes? Is it accurate for neurons?
That the ions are freely moving through the semi-permeable membrane; this is NOT actually the case for neurons due to the sodium-potassium pump
What does it mean if there is an electrical charge or disturbance in the brain?
That there is a change in the distribution of the positive & negative charges
But did Fritsch & Hitzig find as they stimulated areas more & more rostrally into the frontal lobe?
That they were able to get motor movement BUT needed to stimulate with more voltage
Where do the majority of neurons reside? What does this suggest?
The cerebellum - suggests that making well-coordinated physical movements requires a large neural investment
What is the key to success of the photoreceptors?
The *detection* of the presence of light, regardless of whether that detection results in a depolarization or hyperpolarization
Anandamine
The 1st endocannabinoid to be identified; involved in hippocampal plasticity in close association with the glutamatergic neurotransmitter system
What receptor has research focusing on cognitive enhancement targeted? How do drugs like ampakines work?
The AMPA glutamate receptor - these drugs exert an indirect effect on AMPA receptors by modulating neurotransmitter release when the neuron is activated by glutamate, ultimately increasing glutamate release
Weber's law
The JND is a constant proportion of the initial stimulus; the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount) Ex: for a subject to detect a JND in the loudness of low-intensity sounds, one sound must be 10% louder than the other sound
What part of the brain contains 80% of all the brain's neurons? What does this suggest?
The cerebellum - this large neuronal investment suggests that the cerebellum is critical for survival
Nerve growth factor (NGF)
The NGF protein facilitates the growth of axons + dendrites, & enhances the probability of neuronal survival
What brain area, across species, contains more neurons than the cerebral cortex?
The cerebellum --> 3.6 neurons in the cerebellum for every neuron in the cerebral cortex
Color constancy
The ability to continue to perceive that an object is a specific color even under varying perceptual conditions (ex: light dimming)
Why is myelin relevant to the discussion of integration of info in the postsynaptic neuron? How might a demyelinating disease hurt this?
The ability to have a signal arrive in a timely manner or at exactly the same time is very important for integration --> in a demyelinating disease, the signal may get to the correct place BUT because it is slow, it misses coordinating with other inputs, which then may make it so that the 2nd neuron does NOT have an action potential
Response inhibition
The ability to inhibit responses that interfere with the completion of a task
Interoception
The ability to monitor the body's internal processes; the sense of the physiological condition of the body
Proprioception
The ability to sense the position, orientation, & movement of one's own body; the ability to know exactly where your body is in space at any given time
What is the largest gene family in the vertebrate genome? How many of these are functional in humans
The about 1,000 genes that code for receptors of odorant molecules --> only about 300-400 of these receptors are functional in humans
Synaptic cleft
The about 20 nanometers between the 2 neuron membranes; the space between the 2 neurons
Explain integration on the postsynaptic cell
The action potential does NOT just come in & then the next cell fires (or not); rather, the cell body & axon hillock have to integrate all the info (i.e. hierarchical synapses + temporal summation + spatial summation + ionotropic vs. metabotropic receptors + excitatory vs. inhibitory synapses) to decide whether there is enough change to generate an action potential
What happens if myelin is missing or degenerated?
The action potential is halted because of a lack of sodium channels in the spaces previously occupied by the myelin
How does axon potential propagation work in an unmyelinated axon?
The action potential moves incrementally down the axon --> there is an initial action potential in the axon hillock but then the disturbance moves as a graded potential down the length of the axon; when it reaches the next "segment" of the axon, it will generally have enough electrical change to allow this segment to reach threshold & have an action potential, which will then trigger the 3rd segment to have an action potential
Microglial cells
The most prevalent immune cells in the brain; take action when a brain injury is detected
Nicotine
The active ingredient in tobacco, which is found in the leaves of a family of plants called solanaceae
Histone acetylation
The addition of a functional chemical compound called an acetyl group to the histones
What happens when nicotine activates nicotine receptors in the autonomic nervous system in the PNS?
The adrenal gland releases epinephrine & norepinephrine, which leads to increased heart rate, blood pressure, & metabolic rate
Spike-initiation zone
The area in the neuron in which the action potential is initiated
What is the difference between a muscle twitch & the attacks of Flynn's cats?
The attacks are integrated, goal-directed behavior (which is very different from a reflexive muscle twitch)
What do hair cells in the basilar membrane form synapses with?
The auditory nerve
What is a major difference between the auditory system pathway & the visual system pathway?
The auditory system has a clear cut pathway that auditory information must follow (i.e. NO parallel pathways), while the visual system has more choice (i.e. has parallel pathways)
Why is giving Parkinson's patients dopamine NOT an effective treatment?
The blood-brain barrier prevents dopamine from crossing into the brain from the PNS
Scala tympani
The bottom fluid-filled space of the cochlea
What is one of the earliest organ systems that begins to develop in an embryo?
The brain
What is the major issue with Parkinson's disease?
The brain doesn't know which movement to initiate because there's no dopamine coming from rewarding behaviors
Explain how the vertebrate nervous system evolved
The brain evolved into a complex structure that assumed critical responsibility for the organism's survival
What is a problem with the technique of studying the first brains that ever developed through the fossils of the earliest known vertebrates?
The brain is gelatinous SO it does not fossilize (in fact, it is one of the first things that goes away when an animal dies)
Cytoskeleton
The cellular infrastructure made up of the fibers contained within the cell's cytoplasm
What is a remnant of the neural tube from development?
The central canal
What happens once the action potential arrives at the presynaptic terminal?
The change in membrane potential triggers voltage-gated calcium (Ca2+) ion channels to open, leading to an influx of Ca2+ ions that provides a trigger for the synaptic vesicles to merge with the presynaptic membrane & release their neurotransmitters into the synaptic cleft
What holds the lens in place? (2)
The ciliary process & the zonule fibers on either side
What does the fact that olfactory neurons travel to the amygdala signify?
The close association between olfaction & emotions - smell is very integrated into the brain's emotional circuits
Subadditive neural response
The components become even stronger & the integrated response becomes even less exaggerated
Explain the columnar / modular organization of the cerebral cortex
The cortex is a series of functional units that are located like columns; the outermost cells migrate upwards because they're the youngest cells, thus allowing it to become a functional unit because they've talked to all the other cells
Synaptogenesis
The creation of synapses; is especially prevalent during fetal brain development & following injury
Validity
The degree with which a chosen test actually measures what the researcher is interested in measuring
Membrane potential
The difference in charge between the inside & outside of a cell
Lateralization
The difference in function between the 2 hemispheres
Dermatome
The distinct areas of skin that each spinal nerve travels to
What is the membrane potential regulated by?
The distribution of sodium (Na+) & potassium (K+) ions
Loudness (sound localization)
The ear that is closer to the sound will hear it louder than the other ear, which is somewhat blocked by the head
Pharmocodynamics
The effects of the drug & the mechanisms of how the drug works (i.e. what the drug does to the body)
Axon hillock
The entrance gate of the axon; the small bump where the axon begins coming off the cell body
What do changing connections, created by modified dendritic spines, contribute to?
The establishment of neural circuits in the brain
What maintains the rods' depolarized state in the dark / hyperpolarized state in the presence of light?
The flow of sodium ions, which is controlled by cyclic guanosine monophosphate (cGMP)
Synaptogenesis
The formation of new synapses among neurons
What is a potential problem when both ears are facing straight towards a sound?
The frequency can get too high to the point that the ears can't detect sound differences between them
Pitch
The frequency of sound waves (i.e. the change in the sound pressure variation per unit over time); the highness or lowness of a sound / tone
What do the taste cells contact?
The gustatory sensory neurons
How do stress hormones work within the hippocampus?
The hippocampus is activated by stress hormones so that appropriate memories can be formed relating to these experiences
What is unique about the human cerebral cortex?
The human cerebral cortex contains the most neurons of any known mammal
What does the idea of a homeostatic state suggest? What does recent research suggest?
The idea of a homeostatic state suggests that physiological systems have ideal constant values that are maintained under healthy, non-threatening conditions BUT recent research suggests that few physiological systems are maintained at a constant state & instead vary depending on the situation (ex: walking vs. running)
What part of the nervous system is the immune response much stronger in & why? What might this explain?
The immune response is much stronger in the PNS, which has much more exposure to the outside world --> this may explain why PNS nerves regenerate much more readily than CNS nerves
What did the Phinneas Gage case reveal?
The importance of an intact frontal cortex & its interconnections with the subcortical areas
Nasal hemiretina
The inside half of the retina; located by the nose on the eyes on either side
Where might nicotine addiction be centered?
The insula
Loudness / amplitude
The intensity of sound waves; how loud or quiet the sound is
What is brightness determined by?
The intensity of the light stimulus --> amplitude
What happens to the intrafusal muscle spindle organ if the muscle is stretched?
The intrafusal muscle spindle organ is also stretched & can communicate this status via the afferent spinal root to the nervous system, which can then correct the situation by stimulating the antagonist muscle OR inhibiting the stretch
Anhedonia
The lack of reward perception, experienced by the individual as an inability to experience pleasure; may be caused by reduced activity in the brain's reward center during withdrawal
Cerebellum
The large structure located at the base of the skull that makes up 10% of the brain's total volume & contains 4x more neurons than the cerebral cortex; plays an essential role in movement coordination, balance, & muscle tone
Pia mater
The layer of the meninges that is immediately covering the brain's surface
Parvocellular layers
The layers located on the dorsal surface of the LGN; provide identifying details about the stimulus (i.e. "what")
What brain area is implicated in many emotional / affective disorders (ex: anxiety disorders)?
The limbic system
What are most drugs metabolized by?
The liver via the actions of specific enzymes
Absolute threshold
The lowest intensity of a stimulus that a person can detect 50% of the time
What might physical vigor provide clues about?
The male's entire functional genome
Where are multisensory neurons especially abundant?
The midbrain's superior colliculus
Medullary pyramids
The midbrain, pons, & anterior medulla
Arachnoid mater
The middle layer of the meninges that has an underlying space with blood vessels running through it
Scala media
The middle space of the cochlea; contains fluid, in addition to the machinery that allows for hearing (organ of corti)
Optic chiasm
The midline structure in the brain where the visual field information from each eye "crosses over" to the appropriate side of the brain for processing; where information from the eyes can cross over to the other side of the brain
Difference threshold / just noticeable difference (JND)
The minimum amount that a stimulus must change for the subject to detect a difference, regardless of whether the stimulus was light, sound, pressure, or heat
Astrocytes
The most abundant type of CNS glial cell; shaped like stars
Flexor
The muscle that closes the joint Ex: bicep
Extensor
The muscle that opens the joint back up Ex: tricep
What is an exception to skeletal (striatal) muscles being voluntary?
The muscles allowing us to maintain our posture while engaging in various tasks are skeletal BUT often under involuntary control
Where are odorants inhaled into?
The nasal cavity
Action potential
The nerve impulse that is triggered in response to relevant & meaningful info, whether it originates from the environment (ex: a bright light or shrill sound) or from another neuron (as part of a neural network)
What is a possible explanation for the results of the Iowa Gambling Task study?
The neural circuits enabling messages from the emotional areas of the brain to reach the decision making areas were disrupted
How does the brain control the endocrine system?
The pituitary gland
What happens if red & green are equally activated, according to opponent-process theory?
The red vs. green opponent process cell will not do anything (because the red & green signals cancel each other out), which will lead to you seeing yellow
What is the critical event in synaptic transmission?
The release of an appropriate & specific type of neurotransmitters between neurons
Exocytosis
The release of neurotransmitters from the vesicles
Exocytosis
The release of neurotransmitters outside of the neuron into the synaptic cleft
Homeostatic state
The resting state of our physiological responses
What makes the cochlea more responsive to vibrations?
The round window
Vestibular system
The sensory system that responds to gravity and keeps people informed of their body's location in space
Multisensory integration
The simultaneous integration of multiple sensory systems
What would happen if there were more target sites for neurons?
There would be increased places for functional connections SO more cells would survive
Conduction velocity
The speed of the action potential
Explain why a chicken can still run with its head cut off
The spinal cord contains neural networks that are involved in pre-programmed patterned behavior (like running)
Neuroethology
The study of the neural basis of animals' natural behavior, including natural responses
What does the brain look like by the time a baby is full-term?
The surface area of the cerebral cortex has many sulci & gyri
What happens at 2 months, in terms of prenatal brain development?
The swellings are reminiscent of a human brain
What is the most dorsal region of the reticular formation?
The tegmentum
Taste pore
The tiny hole at the top of the taste bud that allows taste information to activate receptor cells in the taste bud
Scala vestibuli
The top fluid-filled space of the cochlea
What types of motor units are characteristic of muscles you have more control over (ex: fingers)?
Those with fewer innervated muscle fibers
What types of motor units are characteristic of muscles you have little fine control over (ex: back muscles)?
Those with greater numbers of innervated muscle fibers by a single axon
Sclera
The white of the eye that goes around the edge
Psychotherapeutics (2)
Therapy target for various mental illnesses; include Prozac, thorazine
What happens when a photon of light is absorbed by rhodopsin in the rods?
There is a change in the shape of retinal, which activates the transformation of a G-protein (transducin) to another form that activates cGMP phosphodiesterase, which works to reduce cGMP concentrations that maintain the open sodium channels --> this results in the closure of the sodium channels & hyperpolarization of the receptor In simpler terms, the rhodopsin molecule changes shape, which opens up channels across the membrane that allow ions to flow across the membrane & cause the cell to fire
Why are action potentials slow?
There is a lot happening during an action potential & all of the movement of ions & voltage-gated ion channels takes time
What is unique about dendritic spines?
They are *motile* so can come & go depending on what kind of experiences are happening
Are taste cells neurons?
They are NOT technically neurons because they do NOT have all of the characteristics of a neuron; BUT they are still receptor cells & have a chemical neurotransmitter that allows them to communicate
What is a benefit of habits?
They are efficient
What happens while neurons are migrating to their final destinations?
They are gaining experience that will help them do their jobs later in life --> when they meet at the midline while crossing over to the opposite side, they tag each other so they know who to be in contact with, which helps define the organization of the brain
What happens once the neurotransmitters are in the synaptic cleft?
They diffuse about in the space because they don't have any machinery to move them --> the goal is for there to be enough of them to activate receptors of the next neuron because if they do, there's a chance that the next neuron will respond to them
Why are reflexes important?
They promote survival, especially because it takes a much longer time for info to travel up to the brain
Neural plate
Thickened region of the ectodermal layer that eventually gives rise to the neural tube; a region that begins to thicken & stand up, thus differentiating itself from the rest of the cell types
Deep telencephalic nuclei
Things that are not the hypothalamus or thalamus BUT are buried deep in the brain
How do myelinated axons increase conduction velocity?
Through saltatory conduction
Interaural differences
Time differences
Refractory period
Time during which the membrane's permeability to Na+ ions is low (i.e. it cannot generate another action potential) because the sodium-potassium is working to bring the cell back to its resting membrane potential; sets a maximum limit on a neuron's firing frequency
Nodes of Ranvier
Tiny gaps between the myelin sheath segments
Why do habits emerge?
To continue to automate the selection & activation of specific movements & free up brain processing for more important tasks
What is the purpose of using both lesion methods & brain-stimulation techniques?
To get an informed picture of the role of various brain areas
What do the oculomotor, trochlear, & abducens nerves working together allow you to do?
To have both eyes working at the same time (ex: can track a car)
Why is sensory specialization important?
To prevent mass confusion & sensory overload
What do the superior colliculus & inferior colliculus work together to do?
To stack / integrate visual, auditory, & other sensory info
Where does information travel to in the corticospinal tract?
To the ventral side of the brain stem, where there is the *pyramidal decussation*
What is the problem with the EQ?
Too general to provide specific information about the distinguishing factors of the human brain because researchers did NOT know what exactly was the most important factor correlated with brain weight (ex: # and/or size of neurons, # and/or size of glia, etc.) --> all 50-gram brains do NOT necessarily contain the same # of neurons because the density of neural & non-neural cells could vary across species
What is the primary sensory portal of raccoons? What is their most prominent strength?
Touch - most prominent strength is the ability to discriminate between objects based on tactile cues
What was Helen Keller's most important sensory portal?
Touch - she could learn about objects in her environment by touching them
What experimental treatment was used on the 6 individuals who become "frozen" as if they had Parkinson's disease? How effective was it?
Transplantation of developing dopaminergic neurons from a fetus in their brains, with the goal of increasing the chances of the cells surviving & maturing into dopamine-producing cells in the adult host brain --> some patients had great improvements in their movement after the treatment BUT subsequent clinical trials demonstrated individual differences in the patients' recovery rates
Corticorubro spinal tract
Travels from the cortex to the rubro (red nucleus in the mesencephalon / midbrain) before going to the spinal cord; allows information coming down from the cortex to be modulated by inputs coming into the midbrain, specifically the red nucleus
Withdrawal symptoms
Troubling symptoms that emerge once the drug use ceases; can include fatigue, reduced pleasure, agitation, vivid dreams, irritability, anxiety, poor concentration
Eustachian tubes
Tubes that extend from the external ear to the back of the throat; function as a pressure equalizer between pressure on the inside & outside of the eardrum
How does TMS work?
When a magnet is used, the current passes along a stimulating coil positioned overt he scalp, which causes an increase in the strength of the magnetic field & subsequently, an increase in electrical current in the affected brain area --> this disrupted electrical current takes the affect brain area momentarily offline SO the neurons are temporarily unable to respond to real-time neuronal messages
Where is the hypothalamus located?
Under the thalamus
Explain how dermatomes relate to functional neuroanatomy
Understanding which parts of the body are within the dermatome for which spinal nerve pair can allow doctors to accurately diagnose things when it comes to spinal cord injuries
What is a unique feature of light transduction in the rods?
Unlike most neurons, rods are *hyperpolarized* by light & remain in a depolarized state in the dark
How long does cortical maturation continue for in humans?
Unlike other mammals, it continues through early adulthood in humans
How many different odors can humans detect?
Up to 10,000 different odors
What types of frequencies can volley theory / cross-fiber theory explain?
Up to 600 Hz
What direction do radial glia project?
Upwards --> move past the cerebral cortex layers that have already been formed in order to form the 6 layers
Echolocation
Used by bats, who generate sounds & analyze the echoes of those sounds to detect the presence of small insects up to 10 m away; also used by whales, dolphins, & has been replicated by scientists who developed sonar used by the military to detect the location of underwater objects (ex: submarines)
How did the basal ganglia used to be viewed as? What has now changed?
Used to be viewed as a "go-through" system, creating a motor loop in which the basal ganglia structures modulate information from cortical areas & then send it back to the cortex for final movement execution; BUT now, we understand that it also processes information from several surrounding brain areas & monitors internal feedback from within the basal ganglia
Stereotaxic atlas
Used to determine the precise location of the brain areas of interest based on a specific landmark (ex: bregma)
L-DOPA
Used to treat Parkinson's disease by increasing levels of dopamine in patients experiencing deficits in this neurotransmitter
Stereotaxic surgery
Uses a precise surgical instrument (stereotaxic apparatus) to accurately target a specific area for a lesion
Diffusion tensor imaging (DTI)
Uses the movement of water in the brain to detect characteristics of the fibers that make up white matter; allows researchers to visualize the network of fibers supporting the brain's communication network & to understand the role of white-matter communications in diseases (ex: Alzheimer's)
Explain how G protein-coupled receptors work
When a ligand binds to a metabotropic receptor, the receptor activates a protein called a G-protein, which is coupled with guanosinetriphosphate (energy-storing molecule) --> this G-protein then activates second messengers within the postsynaptic neuron
What does myelination of certain pathways translate to? Examples? (2)
When people can do certain things Ex: young children move their whole arm at first, but as they myelinate the nerves that go to the arm, they can start being able to use different parts of the arm separately & more easily Ex: memory increases as myelination occurs in the hippocampus
What is a critical step in decoding light?
When the image is projected onto the retina
Saltatory conduction
When the impulse jumps from one node of Ranvier to another one
What are some exceptions to axons having myelin sheaths?
When the nerve impulse doesn't have to travel very far, there might not be a myelin sheath Ex: small neurons in the spinal cord that transmit information about pain are unmyelinated
Explain how hearing works at the inner ear
When the oval window gets a signal from the ossicles, it will begin vibrating, which will then lead the basilar membrane to vibrate at the frequency that it came in --> this vibration causes the organ of corti to move, which then leads to the tectorial membrane vibrating in a free-floating way at a different frequency than the basilar membrane underneath --> this causes "shearing" of the cilia (i.e. they are bent & displaced), which then leads the hair cells to send a signal to the brain
How does myelin speed up signals?
When the signal gets to the end of the myelin, there's still enough of the graded potential to allow the next node of Ranvier section to hit threshold & generate another action potential
When is the loudness idea of sound localization especially helpful?
When the sound is a sustained sound --> can take the time to orient towards it correctly
How do voltage-gated ion channels open?
When the voltage shifts, it puts force on the proteins the make up the channel, causing them to undergo a *conformational change* that allow them to shift just enough for the channel to open
Terminal ending / axon ending / terminal bouton
Where a transfer of message occurs; this usually occurs with some component of a 2nd neuron (ex: a dendritic spine) BUT also can transfer messages to non-neuronal tissue (ex: muscles & glands throughout the body)
What is a behavioral experiment showing that pheremones (& smells in general) can influence our behavior
White t-shirt experiment --> people can predict better than chance: - whether a male or female wore the shirt - which shirt they wore - if the t-shirt came from a family member - which t-shirt their newborn baby wore, even if the mother has not held the baby yet
What does the biofeedback technique demonstrate?
With the appropriate feedback, humans can alter functions like their heart rate & blood flow
Explain how women's ovulation cycles relate to the white t-shirt experiment
Women will rate the pleasantness of t-shirts in differing ways based on their ovulation --> when they are ovulating, they tend to rate the shirts of non-family members as more pleasant, while when they are not ovulating, they tend to rate the shirts of family members as more pleasant
Linda Buck
Won the Nobel Prize for figuring out how the olfactory receptor cells work & that there are 300+ receptors
Explain how T cells & B cells work together?
Work together to establish adaptive immunity by maintaining a memory of the pathogens following the 1st exposure
Explain Fechner's general experiments
Would gradually increase a light / sound / heat & would ask subjects to report when they noticed a change in intensity
Can short & long effects happen at the same time as hyperpolarization (IPSP) or depolarization (EPSP)?
Yes
Do agonist drugs bind to receptor sites?
Yes - they can fit the receptor site & result in a pharmacological response
Can progesterone enter the CNS?
Yes, it can cross the blood-brain barrier to enter the CNS (& the brain even produces some progesterone)
Explain the saying "gains in the brain are all about the stain"
You can only see as much information as the tool you are using allows you to see
Why is it important that the cornea is transparent?
You don't want blood vessels or anything else impeding your ability to see
Explain how dopamine, norepinephrine, & epinephrine build upon each other
You need dopamine to make norepinephrine & you need norepinephrine to make epinephrine
What would happen if the optic nerve was severed in one eye?
You would be completely blind in that eye
What would happen if the optic tract was severed?
You would lose the entire left visual world (or the entire right visual world)
What would happen to your perception of the taste of a jellybean if olfaction was removed?
You would only be able to tell that the jellybean is sweet (NOT that the flavor is cherry, for example)
What evidence do we have that Von Economo neurons may be responsible for hunches / "gut feelings"?
fMRI study revealed that the anterior cingulate cortical area & the frontoinsular cortical (location of the Von Economo neurons) are activated when participants were making fast-paced decisions based on hunches & intuitive thinking, indicating that the Von Economo neurons are likely engaged