Psychology ch 3

What makes up the brain stem?

The MEDULLA OBLONGATA, the PONS, and the MIDBRAIN. A significant blow to this region can cause death.

How does the brain communicate with the body?

The PNS and CNS communicate with one another. Production of psych activity that both these systems interact in a different mode of communication within the body, the endocrine system.

Hippocampus

A brain structure associated with the formation of memories.

3. Norepinephrine

Arousal, vigilance, & attention

Subcortical regions important for understanding psychological functions:

BATHH. 1. Basal ganglia. 2. Amygdala. 3. Thalamus. 4. Hippocampus. 5. Hypothalamus.

Subcortical regions

Below the cerebral cortex.

What happens when the neurotransmitter binds to the receptor?

Can cause ion channels to open or close more tightly, producing an excitatory or inhibitory signal in the postsynaptic neuron. (Excitatory encourages the neuron to fire; inhibitory discourages it.)

What's cognitive therapy about?

Strengthening your frontal lobe.

Neurons communicate by electrochemical signal. Imagine that an NT binds to a postsynaptic receptor. What would happen afterward?

Na channels open. An action potential is generated down the axon. NTs are released into synapse. Through reuptake, the NT returns to the presynaptic neuron. (one scenario)

Subcortical structures control...

Emotions & appetitive (desire to satisfy bodily needs) behaviors

Pons

Regulating sleep, wakefulness.

Heritability

(Not heredity.) A statistical estimate of the extent to which variation in a trait within a population is due to genetics. Ie, trait can't be due to env or chance. The heritability for a trait depends on the VARIATION, or the measure of the overall diff among a group of ppl for that particular trait. Eg w/in a pop of Amer women, height has a heritability of .60. This fig means that 60% of the variation in height among Amer women is genetic. Heritability estimates aid in IDing the causes of diffs between inds in a pop.

Some factors that contribute to the firing of an action potential (pre, during, end):

1. Changes in electrical potential lead to action. 2. Actions potentials spread along the axon. 3. The all-or-none principle.

3 major events that terminate the neurotransmitter's influence in the synapse area are:

1. Reuptake. 2. Enzyme deactivation. 3. Autoreception.

How long does the entire process of the action potential take?

1/1000 of a second. Permits the fast & frequent adjustments required for coordinating motor activity.

How many structural regions does a neuron have that participate in communication functions? What are they?

4. Dendrites, cell body (aka soma), axon, terminal buttons.

Endocrine system

A communication system that uses hormones to influence thoughts, behaviors, and actions. Works, coordinates with nervous system to regulate psych activity. Eg, brain receives info from NS about potential threats. (Like talking in front of a big group.) Brain communicates with endocrine system to deal with those threats.

Autonomic nervous system (ANS)

A component of the PNS; it transmits sensory signals and motor signals between the CNS and the body's glands & internal organs.

Somatic nervous system (SNS)

A component of the PNS; it transmits sensory signals and motor signals between the CNS and the skin, muscles and joints.

Split brain

A condition that occurs when the corpus callosum is surgically cut and the two hemispheres of the brain don't receive info directly from each other. Splits the mind. Left brain won't know what right brain saw.

Electrophysiology

A data collection method that measures electrical activity in the brain.

Electroencephalograph (EEG)

A device that measures electrical activity in the brain. Measurement useful bc diff behavioral states produce different & predictable EEG patterns. Limited as a measure of specific cognitives states. Reflects all brain activity, so it's too "noisy."

Sympathetic division

A division of the ANS; it preps the bod for action. Eg dilated pupils, accelerated heart beat.

Parasympathetic division

A division of the ANS; it returns the body to its resting state. Eg contracts pupils, slows heartbeat.

Myelin sheath

A fatty material, made up of glial cells (support neurons), that insulates some axons (helping them retain their electricity) to allow for faster movement of electrical impulses along the axon. Grows along an axon in short segments.

Pituitary gland

A gland located at the base of the hypothalamus; it sends signals to other endocrine glands, controlling their release of hormones. "Master gland"--controls major processes of the body.

Growth hormone (GH)

A hormone released from the pituitary gland. Prompts bone, cartilage, and muscle tissue to grow or helps them regenerate after injury. The releasing factor for GH stimulates the eating of protein by making it especially enjoyable.

Cerebellum

A large convoluted protuberance at the back of the brain stem; it's essential for coordinated movement and balance.

Axon

A long narrow outgrowth of a neuron by which info is transmitted to other neurons.

Corpus callosum

A massive bridge of millions of axons that connects the hemispheres and allows info to flow between them.

Position emission tomography (PET)

A method of brain imaging that assesses metabolic activity by using a radioactive substance injected into the bloodstream. Enables researchers to find the most active brain areas.

Magnetic resonance imaging (MRI)

A method of brain imaging that uses a powerful magnetic field to produce high-quality images of the brain.

1. Changes in electrical potential lead to action

A neuron receives chem signals from nearby neurons through its dendrites. By affecting polarization, these chem signals tell the neuron whether to fire. The signals arrive at the dendrites by the 1000s and are of two types: excitatory & inhibitory.

Plasticity

A property of the brain that allows it to change as a result of experience or injury. Despite the great precision and the specificity of its contents, the brain is extremely adaptable.

Broca's area

A small portion of the left frontal region of the brain, critical for the production of lang. Damage to this area can result in trouble speaking comprehensively.

Damage to the right parietal region

A stroke or other damage to the right parietal region can result in the neurological disorder HEMINEGLECT. Patients with this syndrome fail to notice anything on their left side even tho their eyes work perfectly well.

Nucleus accumbens

A structure in our basal ganglia. Important for experiencing reward and motivating behavior. Lotsa dopamine activity in this structure.

Basal ganglia

A system of subcortical structures that are important for the planning and production of movement. Damage to the basal ganglia can produce symptoms ranging from Parkinson's disease (also dopamine) to Huntingdon's disease. Can also impair the learning of movement and habits, eg automatically looking for cars before you cross the street. Contains the nucleus accumbens.

Genetic variation

A unique genotype is created at conception, accounting for the tremendous genetic variation of the human species.

Forebrain

Above the brain stem and cerebellum is the forebrain, which consists of the two cerebral hemispheres (left and right). From the outside, the most noticeable part of the brain is the cerebral cortex. Divided into four lobes.

How do action potentials affect communication between neurons?

Action potentials cause neurons to release chems from their terminal buttons. These chems travel across the synapse and are received by other neurons' dendrites. The neuron that sends the signal is called the PRESYNAPTIC NEURON, and the one that receives the signal is called the POSTSYNAPTIC NEURON.

Action potential (aka...?)

Aka neural firing. The electrical signal that passes along the axon & subsequently causes the terminal buttons to release chems that transmit signals to other neurons. Causes neural communication.

Effects of neurotransmitters on action potential

All neurotransmitters have excitatory or inhibitory effects on action potentials by affecting the polarization of the postsynaptic cells.

Function magnetic resonance imaging (fMRI)

An imaging technique used to examine changes in the activity of the working human brain by measuring changes in the blood's oxygen levels.

How is the brain stem similar to the spinal cord?

As a continuous extension of the spinal cord, the brain stem also performs functions for the head similar to those that the spinal cord performs for the rest of the body. Many reflexes emerge from here, eg gagging.

Terminal buttons

At the ends of axons, small nodules that release chem signals from the neuron into the synapse.

3. Autoreception

Autoreceptors monitor how much neurotransmitter has been released into the synapse. When an excess is detected, the autoreceptors signal the presynaptic neuron to stop releasing the neurotransmitter.

Travel of action potential down the axon

Bc of the insulation the myelin sheath provides, the action potential skips quickly along the axon. It pauses briefly to be recharged at each node.

History of psych in terms of brain producing mental activity

Beginning of 1800s, we knew brain's basic structure pretty well. Had no clue how the brain produced mental activity. PHRENOLOGY was developed--a feeling of the skull could reveal personality. Had one thing right: the seemingly scientific principle that brain functions were localized.

Amygdala

Brain structure that serves a vital role in learning to assoc things w emotional responses and in processing emotional info. (Whole limbic system involved, but amygdala is key.) Involved in learning about biologically relevant stimuli, eg stimuli that elicit fear. Intensifies the function of memory during times of emotional arousal. Memories might not be completely accurate, however.

Brain imaging

Brain's electrical activity assoc w changes in the flow of blood. BRAIN IMAGING METHODS measure changes in the rate of the flow of blood to diff regions of the brain. By keeping track of these changes, researchers can monitor which brain areas are active when ppl perform certain tasks or experience certain events. Imaging is a powerful tool for finding where diff systems are in the brain and how diff brain areas interact to process info.

2. Hypothalamus

Brain's master regulatory structure. Regulates indispensable bodily functions, eg blood pressure, eg circadian rhythms. Controls our endocrine system (eg someone startles you, your stress response kicks in. Hypothalamus tells adrenal glands to produce adrenaline). Also influences our basic motivated behaviors, including thirst, hunger, aggression, and lust.

Dendrites

Branchlike extensions of the neuron that detect info/chem signals from other neurons.

4. Serotonin

Celebrate on EID. Emotional states & impulsiveness. (Low levels of serotonin assoc w sad, anxious, food cravings, aggressive behavior. SELECTIVE SEROTONIN REUPTAKE INHIBITORS, like Prozac, target serotonin to treat depression.) Dreaming.

Hormones

Chem substances, released from endocrine glands, that travel through the bloodstream to targeted tissues; bind to receptor sites and the tissues are subsequently influenced by the hormones.

Neurotransmitters

Chems made in the axon and stored in vesicles (small, fluid-filled sacs). When released by the vesicles, the neurotransmitters convey signals across the synapse to postsynaptic cells, from one neuron to another.

3. Interneurons

Communicate within local or short-distance circuits. Integrate neural activity within a single area, don't transmit info to other brain structures or body organs.

Neurons are specialized in...?

Communication. They are powered by electrical impulses and communicate with other nerve cells through chem signals.

What is the functional basis of all psych activity?

Complex networks of neurons sending and receiving signals.

Experience fine-tunes neural connections

Connections form between brain structures when growing axons are directed by certain chems that tell them where to go/where not to go. Major connections established by chemical messengers, but the detailed connections are governed by experience.

Gating mechanism

Controls the flow of ions through each channel. When a gate is open, ions flow in & out of the cell membrane. A closed gate prevents their passage.

Membrane

Covers neuron. A fatty barrier. Semipermeable, so some substances move in/out of the membrane, some don't.

Brain plasticity throughout life

Decreases with age, but old brains can still rewire and grow. The rewiring and growth within the brain reps the biological basis of learning.

Excitatory signals

Depolarize the cell membrane (ie, decrease polarization by decreasing neg charge inside the cell). Through depolarization, these signals increase the likelihood that the neuron will fire.

Complications in amygdala can lead to

Depression, anxiety

1. Sensory neurons

Detect info from the phys world and pass that info to the brain. Usually through the spinal cord. Sensory nerves that provide info from the skin & muscles are called SOMATOSENSORY NERVES.

2. Motor neurons

Direct muscles to contract or relax, thereby producing movement.

Agonists

Drugs & toxins that enhance the actions of NTs

Antagonists

Drugs & toxins that inhibit the actions of NTs.

Problem in Tirets

Dysfunctional basal ganglia. Basal ganglia "the gate." Vocalizations get thru that shouldn't get thru.

Eight NTs are esp important in understanding how we think, feel, and behave. 8 major NTs & their functions follows.

ENDSGAGE. 1. Epinephrine. 2. Norepinephrine. 3. Dopamine. 4. Serotonin. 5. GABA (gamma-aminobutyric acid). 6. Acetylcholine (ACh). 7. Glutamate. 8. Endorphins.

Genes, polypeptides, and protein

Each gene specifies an exact instruction to manufacture a distinct POLYPEPTIDE. One or more polypeptides make up a protein. Proteins are the basic chains that make up the structure of cells and direct their activities. The env determines which proteins are produced and when they are produced.

Why is the electric charge of the neuron the way it is?

Electric charge inside/outside the membrane is different bc ratio of - to + ions is greater inside the neuron than outside. Electric charge inside neuron slightly more - than electric charge outside--typically -70 millivolts.

Endocrine system & NS

Endocrine system ultimately under CNS's control. Brain interprets in/external stimuli, then sends signals to the endocrine system which then responds by initiating various effects on body/behavior. Endocrine system primarily controlled by the hypothalamus via signals to the pituitary gland.

7. Glutamate

Enhancement of action potentials. Learning & memory. (excessive glutamate--overexcitement of brain--seizures, destruction of neurons. Much of the brain damage post stroke or trauma is caused by excessive glutamate that naturally follows a brain injury.

Genetic mutations

Errors occur sometimes during cell division, leading to mutations, or alterations in the DNA. Mutations can be adaptive (benign, produce a selective adv in terms of survival or reproduction) or maladaptive (malign, selective disadv in terms of survival or reproduction). Adaptive mutations may spread thru the pop.

What is the nervous system responsible for?

Everything ppl think, feel, or do.

Brain divided into three sections

Fore-, mid-, and hind-brain. Hind-brain is an extension of spinal surface. Fore-is outer surface. Hind-brain pretty much the same as animals (survival).

Cerebral hemispheres made up of...

Four "lobes": the occipital, parietal, temporal, and frontal lobes.

MONOAMINES

Four transmitters (ENDS: epinephrine, norepinephrine, dopamine, and serotonin) grouped together bc they have the same basic molecular structure. Major functions to regulate arousal, regulate feelings, and motivate behavior.

Prefrontal cortex

Frontmost portion of the frontal lobes, esp prominent in humans: important for attention, working memory, decision making, appropriate social behavior, and personality. Indispensable for rational activity. (Not how much of that part we have, but its complexity that matters.) Provides sense of self and empathy.

1. Thalamus

Gateway to the brain. Receives almost all incoming sensory info, organizes it, and relays it to the cortex. (Can decide to not pay attention to nearby convo til you hear your name pop up.) Only exception is the oldest and most fundamental sense, that of smell. During sleep, the thalamus partially shuts the gate on incoming sensations while the brain rests.

Mechanisms in the membrane that contribute to polarization by affecting ion flow

Gating mechanism, cell membrane's selective permeability, and the sodium-potassium pump.

Medulla oblongata

Goes right to spinal cord. Controls heart, breathing, core life functions. Can live without cortex, midbrain, can't live without a medulla.

Human Genome Project

Has mapped the basic sequence of DNA, providing info that will help scientists increase their understanding of ind diffs in ppl's characteristics and develop treatments for genetically based disorders.

DEEP BRAIN STIMULATION

Helps the motor symptoms of Parkinson's. Stimulates regions affected by the disorder.

Diagram of action potential

Hyperpolarization after repolarization, past -70 millivolts.

Inhibitory signals

Hyperpolarize the cell (ie, increase polarization by increasing the neg charge inside the cell). Through hyperpolarization, these signals decrease the likelihood that the neuron will fire.

6. GABA

IA. Inhibition of action potentials (epileptic seizures may be caused by low levels of GABA). Anxiety reduction (drugs that are GABA agonists are widely used to treat anxiety disorders).

When is the action potential generated as a result of these signals?

If the total amount of excitatory input surpasses the neuron's firing threshold (-55 millivolts), an action potential is generated, aka the neuron is fired.

What is the role of the membrane in communication between neurons?

Important. The membrane controls the movement of ions, so it regulates the concentration of electrically charged molecules (ions) that are the basis of the neuron's electrical activity.

Receptors

In neurons, specialized protein molecules located on the postsynaptic membrane that specifically respond to the chem structure of the neurotransmitter available in the synapse. Neurotransmitters bind to those molecules after passing along the synpase.

Lobotomy

In the 1930s, the LOBOTOMY, a from of brain surgery that deliberately damaged the prefrontal cortex, was developed. Lobotomy left patients lethargic, emotionally flat, and therefore easier to manage.

Brain stem

In the base of the skull. An extension of the spinal cord; it houses structures that control functions associated with survival, eg heart rate, breathing, swallowing, vomiting, urination, and orgasm.

2. Epinephrine

Initially called adrenaline. (inc heart rate & blood sugar). Resp for bursts of energy after an event that's exciting or threatening (the flight-or fight response).

Spinal cord

It's a rope of neural tissue. One of its functions is the coordination of reflexes. Most important function to carry sensory info up to the brain and carry motor signals from the brain to the body parts below to initiate action.

The brain recovering from injury

Just as the brain reorganizes in response to amount of use, it also reorganizes in response to brain damage. Following injury in the cortex, the surrounding gray matter assumes the funct of the damaged area. Remapping. But brain damage is permanent. Can't naturally heal.

Radical hemispherectomy

Kids affected with severe/uncontrollable epilepsy who have paralyzed limb(s) sometimes undergo a radical hemispherectomy, a surgical procedure that removes an entire cerebral hemisphere. Kids' brains can reorganize for this (remaining hemisphere takes over); adults' cannot.

Brain is lateralized

Left and right sides don't do the exact same thing. Lang a highly lateralized skill.

Neurotransmitters bind with specific receptors and their influence upon them

Like a lock and key, each receptor can be influenced by only one type of neurotransmitter. Once a neurotransmitter is released into the synapse, it continues to bind w receptors and continues to exert an excitatory or inhibitory effect. It also blocks new signals until its influence is terminated.

Ion channels

Located in the membrane. Specialized pores that allow IONS to pass in/out of the cell when the neuron transmits signals down the axon. Each channel matches a specific type of ion.

Why different?

Males' brains bigger--doesn't nec mean better. Men and women perform the same cognitive task by using different parts of the brain. Nurture can influence nature: everything a person experiences alters his/her brain. Males/females experience diff things, have diff hormonal makeups. Females' brains more bilaterally organized for language. Also the two halves are connected by more neural fibers.

Estrus

Many nonhuman female animals experience a finite period, estrus, when the female is sexually receptive and fertile. Surgical removal of the ovaries terminates estrus. No longer sexually receptive, female ends sexual behavior. Injection of estrogen reinstates estrus.

Women's sexual behavior

May have to do more with androgens than estrogen. Women's sexual activity not esp linked to menstrual cycle, but linked to ovulation.

Neurotransmitters affect what in general in us?

Mental activity and behavior.

Ions

Molecules, some charged +ly some charged -ly.

Monozygotic v dizygotic twins

Monozygotic: identical twins, share the same genes. Dizygotic: Fraternal, or nonidentical, twins; twins that are no more similar genetically than nontwin siblings.

1. Acetylcholine (ACh).

Motor control over muscles at the junction between muscles and nerves. Learning, memory, sleeping, dreaming (antagonists can cause temp amnesia. Alzheimer's disease diminishes ACh functioning. Agonists can enhance memory).

How do we know what we know about NTs?

Much of what we know has been learned through the systematic study of how drugs and toxins affect emotion, thought, and behavior.

Main difference between the NS and endocrine system in their mode & speed of communication:

NS fast and communicates via electrochemical signals, endocrine system slow & communicates via hormones.

The roles of sodium (Na) and potassium (K) ions

Na & K the most imp ions in contributing to a neuron's resting membrane potential.

Axons without myelin?

Na channels along each part of the membrane must open. Action potentials are still generated, but the speed of conduction is decreased greatly.

How the pituitary gland works

Neural activation causes the hypothalamus to secrete a particular one of its many RELEASING FACTORS. The particular releasing factor causes the pituitary to release a hormone specific to that factor, and the hormone then travels through the bloodstream to endocrine sites throughout the body. Once the hormone reaches the target sites, it touches off the release of other hormones, which subsequently affect bodily reactions or behaviors.

Neuron's response to incoming stimulation

Neural communication depends on a neuron's ability to respond to incoming stimulation. The neuron responds by changing electrically and then passing along signals to other neurons.

All communication systems in this chapter link...

Neurochemical and physiological processes to behaviors, thoughts, and feelings. These systems are fully integrated and interact to facilitate survival.

Neural networks

Neurons communicate selectively w other neurons to form circuits, or neural networks.

Neurons in spatial relation to one another.

Neurons don't touch each other. They're separated by a small space called the synapse.

Basic idea of neuron to neuron communication?

Neurotransmitters bind to receptors across the synapse.

Inside each terminal button are...?

Neurotransmitters. Those chem signals we were just talking about.

Epigenetics

New field of genetic study wherein researchers look at the processes by which the env affects genetic expression. Further research will reveal how ind' life circumstances might change how their genes operate and how such processes may affect future generations.

How do hemispheres normally operate?

Normally work together, complement one another.

Phenotype

Observable physical characteristics, which result from both genetic and env influences.

2. Enzyme deactivation

Occurs when an enzyme destroys the neurotransmitter in the synapse.

Optogenetics

One prob w most studies of brain funct is that they use correl methods. Optogenetics provides precise control over when a neuron fires, enabling researchers to better understand the causal relationship between neural firing and behavior. Optogenetics (and gene manipulation) alter membrane ion channels so that optogenetics can trigger neuron firing.

8. Endorphins

Pain reduction (pain useful. Signals whether hurt or in danger, therefore to escape or withdraw. But pain can interfere with adaptive functioning. If pain interferes w things like eating, competing, or mating, the animals fail to pass along their genes. Endorphins' painkilling, or analgesic, effects help animals perform these behavior even when they are in pain.

Critical periods

Plasticity has critical periods. During these times, particular experiences must occur for development to proceed normally. Eg newborn cat v adult cat getting eyes sown shut and reopened weeks later; former permanently blind, latter eventually regains eyesight.

Castration

Prior to puberty, surgical removal of the testes. Diminishes capacity for an erection, lowers sexual interest. Man castrated post-puberty can perform sexually if he receives the injection of testosterone. So, males' success in sexual behavior depends on having a min amount of testosterone.

1. Reuptake

Process whereby a neurotransmitter is taken back into the presynaptic terminal buttons, thereby stopping its activity. An action potential prompts terminal buttons to RELEASE the neurotransmitter back into the synapse and then take it back for recycling. Reuptake, release.

Neurogenesis

Production of new neurons. May underlie neural plasticity.

Reflexes

REFLEXES are our automatic motor responses. They occur before we even think about those responses. Combination of sensory and motor neurons.

5. Dopamine

RMMP, like the resting membrane potential. Reward and motivation. Motor control over voluntary movement (dopamine depletion indicated by Parkinson's disease). Planning bc additional rewards of objects & experiences.

Occipital lobes

Regions of the cerebral cortex at the back of the brain: important for vision. Includes PRIMARY VISUAL CORTEX, major destination for visual info. Visual info typically organized for the brain in a way that preserves spatial relationships. Secondary visual areas process things like colors, forms, and motions. Important for visualizations, too: your mind's eye.

Frontal lobes

Regions of the cerebral cortex important for movement and higher-level psychological processes assoc w the prefrontal cortex. includes the PRIMARY MOTOR CORTEX. This includes neurons that project directly into the spinal cord to move the body's muscles.

Temporal lobes

Regions of the cerebral cortex important for processing auditory info, for memory, and for object & face perception. Hold the PRIMARY AUDITORY CORTEX, the brain region responsible for hearing. At the intersection of the temporal and occipatal lobes is the FUSIFORM FACE AREA. Damage to this area can cause specific impairments in recognizing people but not objects.

Parietal lobes

Regions of the cerebral cortex: important for the sense of touch and for attention to the environment (like spatial coordination, predicting where thrown ball will go). Left hemisphere receives touch info from right side of bod & vice versa. In each parietal lobe, this info is directed to the PRIMARY SOMATOSENSORY CORTEX (this groups nearby sensations, eg sensations on the fingers are near sensations on the palms). SOMATOSENSORY HOMUNCULUS distorted bc more cortical area is devoted to the bod's more sensitive areas, eg face & fingers.

Psychophysiological assessment

Researchers examine how bodily functions (physiology) change in assoc w behaviors or mental states (psychology). Eg polygraphs (NOT reliable, tho).

Testing agonists/antagonists

Researchers often inject agonists/antagonists into animals to assess how NTs affect behavior. Eg, researchers want to test the hypo that a certain NT in a specific brain region leads to increased eating. Injecting an agonist in that brain region should lead to increased eating. Injecting an antagonist should lead to decreased eating.

Phineas Gage

Rod went through the frontal lobes (exec functions), his personality changed. Reconstruction of his brain tells us that the prefrontal cortex was most damaged by the rod. Realized this area esp concerned w social phenomena.

Sensory & motor neurons & myelin

Sensory & motor neurons must maintain their myelin to generate fast signals over long distances: to allow for your reflexes, which can help you survive. The loss of myelin means that visual info is disrupted and motor actions become jerky and uncoordinated.

Cell body (aka soma)

Site in neuron where info from 1000s of other neurons is collected and integrated.

Nodes of Ranvier

Small gaps of exposed axon, between the segments of myelin sheath, where action potentials take place.

2 primary components of PNS

Somatic nervous system and the autonomic nervous system.

Limbic system

Some subcortical structures belong to the limbic system. This system serves as the border between the evolutionarily older parts of the brain (brain stem & cerebellum) and the evolutionarily newer part (cerebral cortex). Brain structures in limbic system esp imp for controlling emotions and appetitive behaviors. "Wasn't thinking too clearly"--limbic system was dominant over frontal lobe.

"Knockouts"

Some transgenic mice are called knockouts, meaning particular genes have been "knocked out," or rendered inactive by being removed from the genome or disrupted within the genome. This experimental technique (connects genes to functions) has revolutionized genetics.

Chromosomes

Structures within the cell body that are made up of DNA, segments of which comprise individual genes.

Behavioral genetics

Study of how genes and env interact to influence psych activity. Behavioral genetics has provided imp info abt the extent to which bio influences mind, brain, and behavior. Who we are is determined by how are genes are expressed in distinct envs.

Divisions of the ANS

Sympathetic and parasympathetic divisions. Two types of signals, para/sympathetic, travel from the CNS to glands and organs, controlling their activity.

Wernicke's area

Temporal lobe. Understanding lang (incl ASL, reading and/or understanding that reading). Damage to this area can result in trouble understanding, comprehending.

For what two phenomena does the fire together, wire together theory account for?

The "burning in" of an experience (a pattern of neural firing becomes more likely to recur, and its recurrence leads the mind to recall an event), and the ingraining of habits (repeating a behavior makes the person tend to perform that behavior automatically). Wiring in the brain affected by the amount of use.

What is the pituitary gland often referred to as?

The "master gland" of the body: by releasing hormones into the bloodstream, it controls all other glands and governs major processes like development, ovulation, and lactation.

In cross section, the spinal cord is seen to be composed of two distinct tissue types:

The GRAY MATTER (mostly neurons' cell bodies), and the WHITE MATTER (mostly axons and the fatty myelin sheaths that surround them). In the brain, gray matter is mostly neuron bodies that have nonmyelinated axons and communicate w nearby neurons. White matter is mostly myelinated axons that travel between brain regions.

The brain stem houses...

The basic programs of survival.

Neurons

The basic units of the nerv system; cells that receive, integrate & transmit info in the nerv system. They operate through electrical impulses, communicate with other neurons through chemical signals, and form neural networks.

Reticular formation

The brain stem also contains a network of neurons, known collectively as the RETICULAR FORMATION. The reticular formation projects up into the cerebral cortex (outer portion of the brain) and affects general alertness. Also involved in inducing and terminating the different stages of sleep.

Selective permeability

The cell membrane's selective permeability; partially why more K than Na is inside the neuron.

Effects of neurotransmitters on receptors

The effects of a neurotransmitter are not a property of the chem. Instead, the effects are a function of the receptor to which the neurotransmitter binds. As is true of all receptors, whether NT's effects will be excitatory or inhibitory dep's on the receptor.

Resting membrane potential

The electrical charge of a neuron when it is not active.

Synapse

The gap between the axon of a "sending" neuron and the dendrites of a "receiving" neuron; the site at which chem communication occurs between neurons. Chems leave one neuron, cross the synapse, and pass signals along to other neurons' dendrites.

Genotype

The genetic constitution of an organism, determined at the moment of conception.

1980s

The invention of brain imaging methods swiftly and dramatically changed our abilities for studying ongoing mental activity in the working brain. Scientists can now watch the working brain.

Gonads

The main endocrine glands involved in sexual behavior. In males, the testes; in females, the ovaries.

Genome

The master blueprint that provides detailed instructions for everything. Eg how to grow a gallbladder, where the nose gets placed on the face.

Sympathetic division--when is it dominant?

The more aroused you are, the greater the sympathetic system's dominance. Activated by things like a fire alarm, seeing someone attractive--sexual arousal. SNS also activated by psych states like anxiety, unhappiness, or stress.

For patients with multiple sclerosis (MS), what part of their nervous system is damaged?

The myelin sheath, myelin producing cells, and nerve fibers.

Cerebral cortex

The outer layer of brain tissue, which forms the convoluted, wrinkled surface of the brain; the site of all thoughts, perceptions, and complex behaviors. Underlies complex mental activity.

To test w brain imaging methods, regardless of the method. One limitation of brain imaging.

The participant performs a task that differs from the first one in only one way and that reflects the particular mental funct of interest. The researchers then compare images (in fMRI case, to examine diffs in blood flow and therefore brain activity). Limitation is that the findings are necessarily correlational.

3. All-or-none principle

The principle that when a neuron fires, it fires with the same potency each time; a neuron either fires or not--it can't partially fire, although the frequency of the firing can vary. The stronger the stimulation, the more frequently the neuron fires action potentials.

Polygenic

The trait is influenced by many genes (as well as by env). Variety of skin color is polygenic. Not the end product of a single dom/recessive gene pairing.

Genes

The units of heredity that help determine the characteristics of an organism. (Humans have v few genes, but the subtleties in how those genes are expressed and regulated might matter more.)

Transcranial magnetic stimulation (TMS)

The use of strong magnets to briefly interrupt normal brain activity as a way to study brain regions. Limited in that it can only be used for short durations to examine brain areas close to the scalp. When used in conjunction w brain imaging, it's a powerful method for examining which brain regions are necessary for specific psych functions.

Female and male brains -- how do they compare?

They're mostly similar, but have many revealing differences. (One source of data strokes.)

Sodium-potassium pump

This pump increases K and decreases Na inside the neuron, activity that helps maintain the resting membrane potential.

Types of neurons

Three basic types are: 1. sensory neurons (includes somatosensory nerves, skin and muscles), 2. motor neurons, 3. interneurons.

Sum up action potential thru charge?

Thus, during the process, the electrical charge inside the cell starts out slightly - in its initial resting state (-70 millivolts). As the cell fires and allows more + ions inside (depolarization), the charge becomes +. Through natural restoration, including the activity of the Na-K pump, the charge then returns to its slightly - resting state.

Behavioral genetics methods

Twin studies (compare similarities between diff types of twins to determine the genetic basis of sci traits), and adoption studies (compare similarities between bio relatives & adoptive relatives. Similarities among non-biological adopted siblings have more to do w env than genes).

Gonadal hormones

Two major gonadal hormones are identical in males and females. Quantity differs. More ANDROGENS (eg testosterone) in males, more ESTROGENS in females. Gonadal hormones influence the development of secondary sex characteristics (puberty) and sexual behavior.

How many divisions does the nervous system have? What are they?

Two--the central nervous system (CNS) (the brain and spinal cord), and the peripheral nervous system (PNS) (all nerve cells in the body that are not part of the CNS. The PNS includes the somatic and autonomic nervous systems. CNS & PNS are anatomically sep but highly interdependent functions.

Genetics

Used to describe how characteristics are passed along to offspring through inheritance; also refers to processes involved in turning genes "on" and "off."

What happens when the neuron fires? (Long)

When a neuron fires, the Na gates in the cell membrane open. The open gates allow Na ions to rush into the neuron. This influx of Na causes the inside of the neuron to become slightly more +ly charged than the outside. A fraction of a sec later, K channels open up to let K ions inside the cell rush out. This change from a - charge to a + charge inside the neuron is the basis of the action potential. As the ion channels close, the Na ions stop entering the cell. Same with the K ions.

Polarized state

When a neuron has more - ions inside that outside, the neuron's described as being POLARIZED. The polarized state of the resting neuron creates the electrical energy necessary to power the firing of the neuron.

2. Action potential spread along the axon

When the neuron fires, the cell membrane's depolarization moves along the axon like a wave. Na ions rush thru their channels, causing adjacent Na channels to open. Thus, like toppling dominoes, Na ion channels open in a series. The action potential always moves down the axon away from the cell body to the terminal buttons. These electrical signals travel quickly down most axons bc of the fatty myelin sheath that encases and insulates many axons.

Fire together, wire together theory

When two neurons fire simultaneously, the synaptic connection makes these neurons more likely to fire together in the future. Conversely, not firing weakens the connections between the neurons.

Gene expression

Whether a particular gene is turned on or off. Involved in all psych activity. Research has shown that env factors can affect gene expression.

What determines whether a cell becomes a gallbladder or a nose?

Which genes are turned on or off within that cell. These actions are in turn determined by cues from both inside/outside the cell.

What happens when an action potential reaches the terminal buttons?

it causes the vesicles to attach to the presynaptic membrane and release the neurotransmitters into the synapse. These neurotransmitters then travel across the synapse and attach themselves, or BIND, to receptors on the postsynaptic neuron.