NSCI 111 Final Exam

language pathway for repeating a spoken word

- auditory cortex - wernickes - arcuate fasciculus - brocas - motor cortex

brocas

- damage to motor association cortex - nonfluent speech - good comprehension

Wernicke's area

- damage to posterior temporal lobe - fluent speech - poor comprehension

Neural coding of olfaction

-receptors are typically g=protein coupled receptors - olfactory receptor cells are bipolar cells that make up the cranial nerve - each odorant binds to a specific combination of receptors, which produces a unique pattern in glomeruli

Place the sequence of events of the process of long-term potentiation (LTP) in the proper order

1. Glutamate binds to NMDA and AMPA receptors 2. Depolarization leads to a magnesium ion being removed from the NMDA receptor channel 3. Calcium enters through the NMDA receptor channel and activates kinase 4. AMPA receptors are phosphorylated, and more AMPA receptors move into the postsynaptic density in the dendritic spine 5. Activated transcription factors lead to changes in gene transcription, and downstream protein production and structural changes in the cell

speaking a written word

1. striate cortex 2. angular gyrus 3. wernickes 4. arculate fasciculus 5. brocas 6. motor cortex

What behavioral effect defines a Supertasker?

Ability to perform multiple tasks simultaneously with no decrease in performanc

Describe the multiple hit hypothesis of neuropsychiatric disorders. (1 pts) Give a brief explanation of each of the three multiple domains of 'hits'. (1 pt) Then explain how 'hits' or causes of disorders ultimately generate dysfunction in the brain to affect structure/function. (1 pt)

Answer: the Multiple Hit Hypothesis: many risk factors contribute to create a greater likelihood for developing a neuropsychiatric disorder. These include: -Genetic predisposition: inherited genes passed down through families or mutated genes -Environmental toxins: infections, malnutrition, hypoxic conditions, toxins, and fever can increase risk, especially in the pre/perinatal phase -Trauma exposure: social stressors, feelings of isolation, and use of drugs can change a person's physical health and become a risk factor for disease The combination of 'hits' or factors make it more likely for nuerotransmitter dysregulation, causing neurocircuitry dysregulation and structural abnormalities, and thus creating the symptoms of disorders

According to the cell assembly model of memory storage, which of the following is true?

B. Activation of one or more cells in the assembly will lead to activation of the whole assembly, and therefore the entire memory.

touch pathways

DRG cell axon enters spinal cord, sensory receptor cell ascends via dorsal column, synapses iin dorsal column nucleus, decussation in medial leminiscus in medulla, synapse in thalamus, synapse in somatosensory cortex

Which resource would be most valuable for diagnosing a neuropsychiatric disorder

DSM5

What neurotransmitter system is the focus of the major 'hypothesis' of dysregulation in the brain related to schizophrenia, and is targeted by typical antipsychotic medications?

Dopamine

the pain pathway?

Dorsal root ganglion cell enters spinal cord where it synapses, and the next cell crosses to the contralateral side and synapses in thalamus, and the next neuron projects to the somatosensory cortex

Classic experiments identified the medial forebrain bundle (MFB) as the site where what occurred?

Electrical stimulation acted as a reinforcer to increase lever pressing for self-stimulation

What kind of drives underlie feeding behavior in a rat?

Homeostatic mechanisms to maintain energy stores, Hedonic sensation/reward

What feature of the hypothalamus allows it to control endocrine gland activity?

Its connections with the pituitary allows it to release hormones into the bloodstream, for communication to many target regions.

Describe the differences in the magnocellular (M) pathway and parvocellular (P) pathway:

Magnocellular pathway uses rods (for clarity and motion detection even in low light), visual motion processing, and corresponds to the "where". The parvocellular pathway uses cones (for color detection), and the reaction is slow and sustained and determines the "what" of a stimulus.

Describe the role that two different glutamate receptor types play together in the development of long-term potentiation (LTP). How does one receptor affect the other's activity in response to glutamate (be sure to name them to clarify which is which)? (1 pt) Which receptor allows ion flow that is critical for LTP (name that ion!)? (1 pt) How does the level/expression/placement of each receptor change with the development of LTP? (1 pt)

NMDA receptors are activated once AMPA receptors are stimulated by spatial or temporal summation causing the influx of sodium ions and the depolartization of the cell, causing the removal of magnesium ions from the NMDA receptors. The NMDA receptors are needed for long term potentiation with the influx of calcium ions. There are then more AMPA receptors which are themselves phosphorylated and move into the dendritic spine to create the postsynaptic density

When the stress of an exam is over, what is the process that will allow your HPA axis to stop signaling (1 pt), and which molecule (1 pt) is involved in that process (one phrase or sentence)? What happens if that process is not effective, such as is the case when chronic stress occurs?

Negative feedback turns off the HPA axis via CORT unless under conditions of chronic stress in which there is a constant low level of CORT being released, causing the supression of the immune system, growth, reproduction, and digestion, which is detrimental to the system.

What is one specific piece of research evidence provided in class that dopamine is critical for experiencing reward?

One piece of research evidence is that monkeys given juice exhibit increased rate of firing of DA neurons in VTA with reward, and another is that microdialysis in NAc shows higher level of DA after food (especially highly palatable food) compared to baseline

Describe the kind of coding that is used to distinguish different odorants, from receptor activation in olfactory receptor cells to the populations of cells activated in the next steps in the pathway.

Population coding relies on the combination of receptors that are activated by a particular odorant to perceive that scent. Since each olfactory receptor cell expresses one specific receptor, a certain combination of receptor cells will be activated for each unique odorant; they go on to signal to specific mitral cells which carry that coded signal on in the pathway.

What do fMRI and PET imaging share in common?q

Require a scanner, Have good spatial precision (relative to EEG), Show what brain regions are active during a given time period, Measure activity indirectly based on indicators of resource utilization

Describe the basic setup of a "block design" task used in functional neuroimaging. Include what the subject is doing during each phase of the procedure (1 pt; no need to describe a specific task - you can just say "perform the task" or equivalent). Describe how the activity at each phase is then used (1 pt) to produce the results (1 pt; e.g. what are the results we describe from a functional neuroimaging study?).

Subjects are asked to perform a task (ex: listen to a story or report whether they see something) for a period of time, and then asked to rest (e.g. awake with eyes open) for a period of time. Participants alternate between these "blocks," and activity of brain regions is compared across times performing the task versus not. The results tell us what brain regions are more (or less) activated when doing the task, compared to at rest.

What determines what specific type of aphasia will be seen after a stroke? (1 pt) Give examples of two different aphasias and what different effects of stroke you'd expect to see that would explain each aphasia? (2 pts)

The area in which there is disrupted blood and oxygen flow determines which kind of aphasia may be presented. One aphasia is Wernickes, in which the posterior temporal lobe is damaged, causing a reduction in comprehension of language. In Broca's aphasia, the motor association cortex of the frontal lobe is damaged, causing a reduction in speech ability.

When a cell in the hippocampus becomes active in response to an image of a celebrity, what does it most likely represent?

The cell is part of the cell assembly or neural network representing the memory - by activating this cell through recognition it will activate the cells connected in the network. The elements of the visual pathway will be activated first, leading to the ability to recognize the image.

What brain region is considered the "master regulator", sensing perturbations of various systems and responding to maintain homeostasis? (.5 pts) What kind of hormones (i.e. general molecular structure) are produced here?

The hypothalamus is the master regulator of the endocrine system and releases steroid hormones. In the HPA axis, the hypothalamus releases CRH to the anterior pituitary, which releases ACTH to the adrenal gland to produce cortisol, which is the stress hormone in humans and causes physiological arousal and supression of the immune system, growth, reproduction, and digestion in order to covert the energy into movement. This is a negative feedback system, so the cortisol will then supress the activation of the HPA axis at the hypothalamus once the stressor is over.

Describe the place theory for encoding sound frequency, including the relative locations where high and low frequency are processed in the cochlea. (2 pts) Why can't volley theory explain all frequencies of sound? (1 pt)

The place theory uses the idea that the location of the hair cell on the basilar membrane determines sound frequency such that hair cells in the base of the cochlea code for high frequency sounds since this area of the cochlea is narrow and rigid. This theory best explains high frequency sounds, though it states that low frequency sounds are coded for at the apex, which wide and floppy. The volley theory states that sound frequency is based on the firing speed of action potentials, but this does not explain high frequency sounds, such that action potentials cannot be generated that quickly.

gustatory system

This structure is a taste receptor cell from the gustatory sensory system. The first order neurons synapse in the gustatory nucleus, the second order neurons synapse to the thalamus, and the third order neurons synapse to the primary gustatory cortex.

What is the effect of the partial decussation of the visual system?

Visual input from the right visual field is transmitted to the left side of the brain, and vice-versa.

foxp2

a. Codes for a transcription factor that activates other genes b. Mutations in the FOXP2 gene lead to difficulty with movement of lower facial muscles for speech production c. A family with many members with a mutation in the FOXP2 gene demonstrated little to no speech production and other poor cognitive skills

evidence for universality of human language capability

a. Infants process language in the same brain regions as adults b. American Sign Language uses the same pathways as verbal language c. A patient with brain injuries or strokes affecting language can sometimes recover abilities by recruiting other brain regions d. Specific language areas like Broca's are located in the same place in most individuals. e. brain areas not normally involved in communication can be recruited to do so

PET

activation of specific brain regions in a given condition with temporal resolution in minutes

fmri

activation of specific brain regions in response to a stimulus with millisecond precision

In addition to the hippocampus, this region is important in learning from sensory inputs, especially emotional learning:

amygdala

true about the dorsal column and anterolateral pathways?

both pathways involve tracts that ascend from spinal cord to brain, first order cell for both is the dorsal root ganglion, Receptors in the dorsal column pathway are encapsulated by connective tissue structures, while the receptors in the anterolateral pathway occur at free nerve endings.

correct regarding similarities and differences between the NMDA receptor and the AMPA receptor

both play a role in development of LTP, only NMDA receptors are blocked by Mg ion at rest and are permeable to Ca+ when activated, both are glutamate receptors

receptor potential

change in membrane potential in a receptor cell inresponse to appropriate stimulus

taste buds

clusters of cells, each cell responding to specific tastant

auditory pathway

cochlea - cochlear nucleus - superior olive - inferior colliculus - thalamus - auditory cortex

positive symptoms of schizophrenia

delusions, hallucinations, anhedonia

negative symptoms schizophrenia

disorganized speech, difficulty initiating goal directed behavior , social deficits

the nerve ending of a Pacinian Corpuscle

encapsulated in connective tissue and responds to pressure

sensory memory

fleeting memory of sensations

the article we discussed in class by Medeiros-Ward, Watson and Strayer focused on attention in Supertaskers. What specific technique was used to observe activity in the brain when subjects changed their cognitive load? [A] What two brain regions were the focus of the study, where significant group differences were found? [B]

fmri, PFC and ACC

A slow adapting receptor will fire

for the duration a stimulus is applied

[A] is a peptide hormone that acts as an orexigenic signal when it is released from the stomach. It acts on receptors in the [B] which regulates feeding behavior to maintain homeostasis. This orexigenic signal is a [C]-term (short/long) signal, which will lead to a(n) [D] (increase/decrease) in feeding

ghrelin, hypothalamus, short, increase

engram

group of cells that collectively store a memory

When stimulated by light, photoreceptor cells are __________, leading to __________release.

hyperpolarized, decreased glutamate

Why is attention important?

improves reaction time, enhances sensory sensitivity

calcium

ion critical for LTP that activates kinases

short term

memory lasting minutes that has not yet been permanently stored

working memory

memory lasting seconds to minutes that allows you to keep info available without permanently storing it

declarative

memory of facts

What type of information is detected by the muscle spindle

muscle stretch and proprioceptive stimuli

consolidation

process by which long term memories are stored, requiring protein synthesis

refraction

process by which the cornea and lens bend light so that it hits a specific part of the retina (fovea)

vestibular pathway

projections to brain regions controlling reflexive movements, projectections from vestibular apparatus via vestibular nerve, projections to cerebellum

Define the term proprioception. Is this a conscious or unconscious type of somatosensation?

proprioception is the sense of where the body is in space - there are both conscious and unconscious proprioceptive pathways.

hair cells

releasse neurotransmittger

A patient with brain trauma cannot remember events prior to the time of trauma. Which type of amnesia does this symptom indicate?

retrograde

Which of the following pathways play an important role in sexual behavior?

somatosensation, reward, movement, autonomic nervous system

MRI

structures

Where do SECOND order neurons in the auditory pathway synapse on THIRD order neurons?

superior olivary nucleus

What is common to all sensory systems:

they receive an external stimulus, transduce a specific stimulus into an electrochemical signal, signal moves through pathway to the brain

relays of gustatory

tongue, gustatory nucleus, thalamus, primary gustatory cortex ; first order neurons relay at the gustatory nucleus at the medulla

nondeclarative

type of memory that includes skills such as riding a bike

theory for low freq sounds

volley theory

DTI

white matter tracts