Unit 2 AP Psychology Exam - Biological Bases of Behavior

Acetylcholine

• enables muscle action, learning, and memory

• Alzheimer's disease, ACh-producing neurons deteriorate

Dopamine

• influences movement, learning, attention, and emotion

• Oversupply linked to schizophrenia

• Undersupply linked to tremors and decreased mobility in Parkinson’s Disease

Serotonin

• affects mood, hunger, sleep, and arousal

• Undersupply linked to depression

• Some drugs that raise serotonin levels are used to treat depression.

Norepinephrine

• helps control alertness + arousal

• Undersupply can depress mood

GABA

• gamma-aminobutyric acid

• a major inhibitory neurotransmitter

• Undersupply linked to seizures, tremors, and insomnia

Glutamate

• a major excitatory neurotransmitter; involved in memory

• Oversupply can overstimulate the brain, producing migraines or seizures (which is why some people avoid MSG, monosodium glutamate, etc in food)

Endorphins

• neurotransmitters that influences the perception of pain + pleasure

• Oversupply wit opiate drugs can suppress the body’s natural endorphin supply

Neuron

a nerve cell; the basic building block of the nervous system

The Cell Body

• the part of a neuron that contains the nucleus

• the cell's life-support center

dendrites

• (The little branch-looking things near the head)

• branching extensions that receive messages and conduct impulses toward the cell body

axon

The extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

Myelin Sheath

• Covers the axon of some neurons and helps speed up neural impulses.

• A layer of fatty tissue segmentally encasing the fibers of many neurons

• enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

Glial Cells

Support, protect, and nourish neurons

action potential

A brief, electrical impulse that travels down a neuron’s axon to allow cells to communicate

threshold

The level of stimulation required to trigger a neural impulse.

refractory period

• the time following an action potential during which a new action potential cannot be initiated

• Neurons need short breaks before they can fire again

all-or-nothing response

• More stimulation does not produce a more intense neural transmission.

• Neurons either fire or they don't (like a gun)

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

neurotransmitters

chemical messengers that travel across the synapse and bind to receptor sites on the receiving neuron

reuptake

a neurotransmitter’s reabsorption by the sending neuron

endorphins

• "morphine within"

• Natural, opiatelike neurotransmitters linked to pain control and to pleasure.

agonist

A chemical substance that binds to a receptor to amplify or mimic a natural neurotansmitter

antagonist

A chemical substance that blocks receptor sites to reduce the effect of a neurotransmitter

nervous system

• The body’s main control + communication network that coordinates all actions + etc.

• Neurons release transmitters

• Neurotransmitters move across synapses

central nervous system

• the main control center of your body, consisting of the brain and the spinal cord

• Includes the brain + spinal chord

peripheral nervous system

the sensory and motor neurons that connect the central nervous system to the rest of the body

nerves

cord-like bundles of fibers that carry electrical and chemical signals between your brain, spinal cord, and the rest of your body

sensory neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord

motor neurons

• specialized nerve cells that carry electrical and chemical signals from your central nervous system to your muscles and glands to trigger movement and control bodily functions

• ex. What tells you to reach for an object

interneurons

neurons within the brain and spinal cord that communicate internally and intervene between the sensory inputs and motor outputs

somatic nervous system

• Controls voluntary muscle movements

• Transmits sensory information from the skin, sensory organs, and skeletal muscles to the central nervous system

• The division of the peripheral nervous system that controls the body's skeletal muscles

autonomic nervous system

• A subdivision of the peripheral nervous system

• Controls involuntary activity of visceral muscles and internal organs and glands.

sympathetic nervous system

• the division of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations

• “fight-or-flight”

parasympathetic nervous system

• Part of the The autonomic nervous system; controls involuntary “rest + digest” functions

• Norepinephrine is also released here.  This part of your body acts like a “break” in a car.

reflex

• Occurs only in the spinal chord before information reaches the brain

• Happens without your conscious knowing its happening to protect you from immediate danger.

• knee-jerk

endocrine system

• the body's "slow" chemical communication system

• a set of glands that secrete hormones into the bloodstream

hormones

chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues

adrenal glands

• A pair of endocrine glands that sit just above the kidneys

• Secrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress

pituitary gland

• The endocrine system's most influential gland

• Under the influence of the hypothalamus

• Regulates growth and controls other endocrine glands.

lesion

• tissue destruction

• A brain lesion is a naturally or experimentally caused destruction of brain tissue

EEG

• An amplified recording of the waves of electrical activity that sweep across the brain's surface

• These waves are measured by electrodes placed on the scalp.

MEG

a brain imaging technique that measures magnetic fields from the brain's natural electrical activity

CT Scan

• A series of X-ray photographs taken from different angles

• combined by a computer into a composite representation of a slice of the brain

PET

a visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

MRI

• a technique that uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of soft tissue

• allows us to see structures within the brain

fMRI

A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans

brainstem

• The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull

• responsible for automatic survival functions

medulla

• the base of the brainstem

• controls heartbeat and breathing

thalamus

• The brain's sensory switchboard

• located on top of the brainstem

• It directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

reticular formation

a nerve network in the brainstem that plays an important role in controlling arousal

cerebellum

• the "little brain" at the rear of the brainstem

• functions include processing sensory input and coordinating movement output and balance

limbic system

• neural system (including the hippocampus, amygdala, and hypothalamus) located below the cerebral hemispheres

• associated with emotions and drives

amygdala

• two lima bean-sized neural clusters in the limbic system

• linked to emotion

hypothalamus

• A neural structure lying below the thalamus

• it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland

• linked to emotion and reward

hippocampus

A neural center located in the limbic system that helps process explicit memories for storage

cerebral cortex

• The intricate fabric of interconnected neural cells covering the cerebral hemispheres

• the body's ultimate control and information-processing center

frontal lobes

• the portion of the cerebral cortex lying just behind the forehead

• involved in speaking and muscle movements and in making plans and judgments

parietal lobes

• portion of the cerebral cortex lying at the top of the head and toward the rear

• receives sensory input for touch and body position

occipital lobes

• portion of the cerebral cortex lying at the back of the head

• includes areas that receive information from the visual fields

temporal lobes

• portion of the cerebral cortex lying roughly above the ears

• includes the auditory areas, each receiving information primarily from the opposite ear

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements

somatosensory cortex

• area at the front of the parietal lobes

• registers and processes body touch and movement sensations

association areas

• Areas of the cerebral cortex

• Not involved in primary motor or sensory functions

• Rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

plasticity

The brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

neurogenesis

the formation of new neurons

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them.

split brain

a condition resulting from surgery that isolates the brain's two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them.

consciousness

our awareness of ourselves and our environment

cognitive neuroscience

the interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language)

dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks

blindsight

a condition in which a person can respond to a visual stimulus without consciously experiencing it

parallel processing

• The processing of many aspects of a problem simultaneously

• The brain's natural mode of information processing for many functions, including vision

• Contrasts with the step-by-step (serial) processing of most computers and of conscious problem solving

sequential processing

• the processing of one aspect of a problem at a time

• used when we focus attention on new or complex tasks

behavior genetics

the study of the relative power and limits of genetic and environmental influences on behavior

heredity

the passing on of physical or mental characteristics genetically from one generation to another.

environment

every nongenetic influence, from prenatal nutrition to the people and things around us

chromosomes

Threadlike structures made of DNA molecules that contain the genes

DNA

A complex molecule containing the genetic information that makes up the chromosomes.

genes

• the biochemical units of heredity that make up the chromosomes

• a segment of DNA capable of synthesizing a protein

genome

the complete instructions for making an organism, consisting of all the genetic material in that organism's chromosomes

identical twins

twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms

fraternal twins

• twins who develop from separate fertilized eggs

• They are genetically no closer than brothers and sisters, but they share a fetal environment

heritability

• The proportion of variation among individuals that we can attribute to genes

• The heritability of a trait may vary, depending on the range of populations and environments studied

interaction

the interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

molecular genetics

the subfield of biology that studies the molecular structure and function of genes

molecular behavior genetics

the study of how the structure and function of genes interact with our environment to influence behavior

epigenetics

the study of environmental influences on gene expression that occur without a DNA change

evolutionary psychology

the study of the evolution of behavior and the mind, using principles of natural selection

natural selection

the principle that, among the range of inherited trait variations, those contributing to reproduction and survival will most likely be passed on to succeeding generations

mutation

a random error in gene replication that leads to a change

social script

culturally modeled guide for how to act in various situations

sleep

periodic, natural loss of consciousness--as distinct from unconsciousness resulting from a coma, general anesthesia, or hibernation

circadian rhythm

the biological clock; regular bodily rhythms that occur on a 24-hour cycle

REM sleep

• Rapid eye movement sleep, a recurring sleep stage during which vivid dreams commonly occur

• Also known as paradoxical sleep, because the muscles are relaxed (except for minor twitches) but other body systems are active

Alpha waves

the relatively slow brain waves of a relaxed, awake state

NREM sleep

non-rapid eye movement sleep; encompasses all sleep stages except for REM sleep

hallucinations

false sensory experiences, such as seeing something in the absence of an external visual stimulus

hypnagogic sensations

sensations of falling or floating while transitioning to sleep

delta waves

the large, slow brain waves associated with deep sleep

suprachiasmatic nucleus

a pair of cell clusters in the hypothalamus that controls circadian rhythm