AP Psychology Unit 2

Neuron

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

cell body

the part of a 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 fibers 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

(1) a period of inactivity after a neuron has fired.;subsequent action potentials cannot happen until the axon returns to its resting state (2) a resting period after orgasm, during which a man cannot achieve another.

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

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

the brain + spinal cord

peripheral nervous system

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

nerves

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

sensory (afferent) neurons

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

motor (efferent) 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. (AKA Skeletal Nervous System)

autonomic nervous system (ANS)

a component of the peripheral nervous system that regulates involuntary physiologic processes including heart rate, blood pressure, respiration, digestion, and sexual arousal.

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

a network of glands across the body that secrete chemical messages called hormones.

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, the pituitary regulates growth and controls other endocrine glands.

lesion

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

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.

MEG (magnetoencephalography

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

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. MRI scans show brain anatomy.

fMRI (functional MRI)

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

brainstem

the oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is 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 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; helps process for storage explicit (conscious) memories of facts and events.

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

an area at the front of the parietal lobes that registers and processes body touch and movement sensations

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

plasticity

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

neurogensesis

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 subjective 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 several aspects of a problem simultaneously; the brain's natural mode of information processing for many functions.

sequential processing

processing one aspect of a problem at a time; generally used to process new information or to solve difficult problems

behavior genetics

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

heredity

the genetic transfer of characteristics 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.

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

"above" or "in addition to" (epi) genetics; 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

social script

a culturally modeled guide for how to act in various situations

Methamphetamine

a powerfully addictive drug that stimulates the central nervous system, with speeded-up body functions and associated energy and mood changes; over time, appears to reduce baseline dopamine levels

Ecstasy (MDMA)

a synthetic stimulant and mild hallucinogen. Produces euphoria and social intimacy, but with short-term health risks and longer-term harm to serotonin-producing neurons and to mood and cognition.

Hallucinogens

psychedelic ("mind-manifesting") drugs, such as LSD, that distort perceptions and evoke sensory images in the absence of sensory input

near-death experience

an altered state of consciousness reported after a close brush with death (such as through cardiac arrest); often similar to drug-induced hallucinations

LSD

a powerful hallucinogenic drug; also known as acid (lysergic acid diethylamide)

THC

the major active ingredient in marijuana; triggers a variety of effects, including mild hallucinations

hypnosis

a social interaction in which one person suggests to another that certain perceptions, feelings, thoughts, or behaviors will spontaneously occur

posthypnotic suggestion

a suggestion, made during a hypnosis session, to be carried out after the subject is no longer hypnotized; used by some clinicians to help control undesired symptoms and behaviors

dissociation

a split in consciousness, which allows some thoughts and behaviors to occur simultaneously with others

sleep

a 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

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