AP Psych Unit 2 Test

Neuron

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

cell body

The part of the neuron that contains the nucleus; the cell's life-support center

Dendrites

a neuron's bushy, branching extensions that receive messages and conduct impulses toward the cell body

Axon

the neuron extension that passes messages through its branches to other neurons or to muscles or glands

myelin sheath

A layer of fatty tissue segmentally encasing the axons of many neurons; enables vastly greater transmission speed of neural impulses as the impulse hops from one node to the next.

glial cells

cells in the nervous system that support, nourish, and protect neurons

action potential

a neural impulse; a brief electrical charge that travels down an axon

threshold

the level of stimulation required to trigger a neural impulse

refractory period

in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state

all-or-none response

a neuron's reaction of either firing (with a full-strength response) or not firing.

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 cross the synaptic gaps between neurons

Reuptake

a neurotransmitter's reabsorption by the sending neuron

Endorphins

"morphine within"--natural, opiate-like neurotransmitters linked to pain control and to pleasure.

Agonist

a molecule that increases a neurotransmitter's action

Antagonist

a molecule that inhibits or blocks a neurotransmitter's action

REM 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.

NREM sleep

encompasses all sleep stages except for REM sleep

hypnagogic sensations

bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep

suprachiasmatic nucleus (SCN)

a pair of cell clusters in the hypothalamus that controls circadian rhythm. In response to light, the SCN causes the pineal gland to adjust melatonin production, thus modifying our feelings of sleepiness

manifest content

according to Freud, the remembered story line of a dream

latent content

according to Freud, the underlying meaning of a dream

consciousness

our awareness of ourselves and our environment

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

alpha waves

the relatively slow brain waves of a relaxed, awake state

Hallucinations

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

delta waves

the large, slow brain waves associated with deep sleep

insomnia

recurring problems in falling or staying asleep

Narcolepsy

A sleep disorder characterized by uncontrollable sleep attacks. The sufferer may lapse directly into REM sleep, often at inopportune times.

sleep apnea

a sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings

night terrors

a sleep disorder characterized by high arousal and an appearance of being terrified; unlike nightmares, night terrors occur during NREM-3 sleep, within two or three hours of falling asleep, and are seldom remembered

REM rebound

the tendency for REM sleep to increase following REM sleep deprivation (created by repeated awakenings during REM sleep)

lesion

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

MEG (magnetoencephalography)

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

EEG (electroencephalogram)

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.

CT (computed tomography) scan

a series of X-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body. Also called CAT scan.

PET (positron emission tomography) scan

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

MRI (magnetic resonance imaging)

a technique that uses magnetic fields and radio waves to produce computer-generated images of soft tissue

fMRI (functional MRI)

A technique for revealing bloodflow 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; it is responsible for automatic survival functions

Medulla

the base of the brainstem; controls heartbeat and breathing

Thalamus

the brain's sensory control center, 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, and is linked to emotion and reward.

Hippocampus

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

behavior genetics

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

Heredity

Passing of traits from parents to offspring

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 (deoxyribonucleic acid)

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 (monozygotic) twins

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

fraternal (dizygotic) twins

develop from separate fertilized eggs. They are genetically no closer than ordinary brothers and sisters, but they share a prenatal 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.

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 inherited traits that better enable an organism to survive and reproduce in a particular environment will (in competition with other trait variations) most likely be passed on to succeeding generations

Mutation

a random error in gene replication that leads to a change

peripheral nervous system

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

nervous system

the body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems

central nervous system

brain and spinal cord

Nerves

bundled axons that form neural "cables" connecting the central nervous system with muscles, glands, and sense organs

sensory neurons

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

motor neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands

Interneurons

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

somatic nervous system

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

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart)

sympathetic nervous system

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

parasympathetic nervous system

the division of the autonomic nervous system that calms the body, conserving its energy

reflex

a simple, automatic response to a sensory stimulus, such as the knee-jerk response

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 and 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, it regulates growth and controls other endocrine glands.

occipital lobe

portion of the cerebral cortex lying at the back of the head; includes areas that receive information from the visual fields

temporal lobe

portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each receiving information primarily from the opposite ear

association areas

areas of the cerebral cortex that are not involved in primary motor or sensory functions; rather, they are involved in higher mental functions such as learning, remembering, thinking, and speaking

neurogenesis

the formation of new neurons

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

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

sequential processing

the processing of one aspect of a problem at a time

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 that registers and processes body touch and movement sensations

Plasticity

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

corpus callosum

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

consciousness

our subjective awareness of ourselves and our environment

cerebral cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center.

frontal lobe

portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgements

parietal lobe

A portion of the cerebral cortex lying at the top of the head and toward the rear; receives sensory input for touch and body position

substance use disorder

disorder characterized by continued substance craving and use despite significant life disruption and/or physical risk