AP Psychology - All Terms

nature–nurture issue

The controversy over the contributions of genes and experience to the development of psychological traits and behaviors.

natural selection

The principle that inherited traits enabling an organism to survive and reproduce are likely to be passed on to succeeding generations.

evolutionary psychology

The study of the evolution of behavior and mind using principles of natural selection.

behavior genetics

The study of the relative influence of genetic and environmental factors on behavior.

mutation

A random error in gene replication leading to a change.

environment

Every nongenetic influence, from prenatal nutrition to experiences with people and things.

heredity

The genetic transfer of characteristics from parents to offspring.

genes

The biochemical units of heredity.

genome

The complete instructions for making an organism.

identical (monozygotic) twins

Individuals developed from a single fertilized egg that split in two, creating two genetically identical organisms.

fraternal (dizygotic) twins

Individuals developed from separate fertilized eggs, no closer genetically than ordinary siblings.

interaction

The interplay that occurs when the effect of one factor depends on another factor.

epigenetics

The study of how environments influence genetic expression without a DNA change.

nervous system

The body's speedy, electrochemical communication network comprising all nerve cells.

central nervous system (CNS)

The brain and spinal cord.

peripheral nervous system (PNS)

The sensory and motor neurons connecting the CNS to the rest of the body.

nerves

Bundled axons forming neural cables connecting the CNS with muscles, glands, and sensory organs.

sensory (afferent) neurons

Neurons carrying incoming information from the body’s tissues 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 and process information.

somatic nervous system

The division of the PNS controlling the body's skeletal muscles.

autonomic nervous system (ANS)

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 ANS that arouses the body, mobilizing its energy.

parasympathetic nervous system

The division of the ANS that calms the body and conserves energy.

reflex

A simple, automatic response to a sensory stimulus.

neuron

A nerve cell; the basic unit of the nervous system.

cell body

The part of a neuron containing the nucleus; the cell's life-support center.

dendrites

Branching extensions of a neuron that receive and integrate messages.

axon

The segmented extension of a neuron passing messages to other neurons or muscles.

myelin sheath

A fatty tissue layer encasing axons, speeding up neural impulse transmission.

glial cells (glia)

Cells supporting, nourishing, and protecting neurons in the nervous system.

action potential

A neural impulse; a brief electrical charge traveling down an axon.

threshold

The level of stimulation needed to trigger a neural impulse.

refractory period

A brief resting pause after a neuron fires, preventing subsequent action potentials.

all-or-none response

A neuron's reaction of either firing or not firing with full strength.

synapse

The junction between sending and receiving neurons, including the synaptic gap.

neurotransmitters

Chemical messengers crossing the synaptic gap between neurons.

reuptake

The reabsorption of a neurotransmitter by the sending neuron.

endorphins

Natural, opioid-like neurotransmitters linked to pain control and pleasure.

agonist

A molecule that increases a neurotransmitter's action.

antagonist

A molecule that inhibits or blocks a neurotransmitter's action.

endocrine system

The body's slow chemical communication system; glands secreting hormones.

hormones

Chemical messengers manufactured by endocrine glands affecting other tissues.

psychoactive drug

A chemical substance altering brain function, affecting perceptions and moods.

substance use disorder

A disorder involving continued substance use despite disruption in life.

depressants

Drugs that reduce neural activity and slow body functions.

tolerance

The diminishing effect of a drug with regular use requiring larger doses.

addiction

Compulsive substance use or behavior continuing despite harmful consequences.

withdrawal

Discomfort following the discontinuation of an addictive drug or behavior.

barbiturates

Drugs that depress CNS activity, reducing anxiety but impairing memory.

opioids

Opiates and derivatives that depress neural activity, lessening pain and anxiety.

stimulants

Drugs that excite neural activity and speed up body functions.

hallucinogens

Psychedelic drugs distorting perceptions and evoking sensory images.

near-death experience

An altered state of consciousness reported after a close brush with death.

biological psychology

The study of the links between biological and psychological processes.

biopsychosocial approach

An integrated approach incorporating biological, psychological, and social-cultural levels.

levels of analysis

Complementary views for analyzing any phenomenon, from biological to social-cultural.

neuroplasticity

The brain's ability to change, reorganizing after damage or based on experience.

lesion

Tissue destruction in the brain, either naturally or experimentally.

EEG (electroencephalogram)

An amplified recording of electrical activity waves across the brain.

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 combined into a composite representation of the brain.

PET (positron emission tomography)

A technique for detecting brain activity that displays where a radioactive form of glucose goes while the brain performs a given task.

MRI (magnetic resonance imaging)

Technique using magnetic fields and radio waves to produce images of soft tissue.

fMRI (functional MRI)

Technique revealing brain activity by comparing successive MRI scans.

hindbrain

Consists of the medulla, pons, and cerebellum; directs essential survival functions, such as breathing, sleeping, and wakefulness, as well as coordination and balance.

midbrain

Found atop the brainstem; connects the hindbrain with the forebrain, controls some motor movement, and transmits auditory and visual information.

forebrain

Consists of the cerebral cortex, thalamus, and hypothalamus; manages complex cognitive activities, sensory and associative functions, and voluntary motor activities.

brainstem

The central core of the brain, responsible for automatic survival functions.

medulla

The hindbrain structure that is the brainstem’s base; controls heartbeat and breathing.

thalamus

The forebrain’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 that travels through the brainstem into the thalamus; it filters information and plays an important role in controlling arousal.

cerebellum

The hindbrain’s “little brain” at the rear of the brainstem; its functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory.

limbic system

Neural system located mostly in the forebrain — below the cerebral hemispheres — that includes the amygdala, hypothalamus, hippocampus, thalamus, and pituitary gland; associated with emotions and drives.

amygdala

Neural clusters in the limbic system linked to emotion.

hypothalamus

A limbic system neural structure; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system, and is linked to emotion and reward.

hippocampus

A neural center in the limbic system that helps process explicit (conscious) memories — of facts and events — for storage.

cerebral cortex

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

frontal lobes

The portion of the cerebral cortex lying just behind the forehead. They enable linguistic processing, muscle movements, higher- order thinking, and executive functioning (such as making plans and judgments).

parietal lobes

Cerebral cortex area receiving sensory input for touch and body position.

occipital lobes

Cerebral cortex area receiving visual field information.

temporal lobes

Cerebral cortex area involved in auditory processing and language.

motor cortex

Cerebral cortex area controlling voluntary movements.

somatosensory cortex

A cerebral cortex 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 involved in higher mental functions such as learning, remembering, thinking, and speaking.

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

Condition resulting from surgery separating the brain's two hemispheres.

consciousness

Our subjective awareness of ourselves and our environment.

cognitive neuroscience

The interdisciplinary study of the brain activity linked with cognition (thinking, knowing, remembering, and communicating).

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

Processing multiple aspects of a stimulus or problem simultaneously.

sequential processing

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

sleep

A periodic, natural loss of consciousness — distinct from unconsciousness from a coma, general anesthesia, or hibernation.

circadian rhythm

Our 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.

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.