AP Psychology Units 1.1–1.4 Vocabulary

A complete set of vocabulary flashcards covering key terms and definitions from AP Psychology Units 1.1 through 1.4.

Biological psychology

The study of how biological processes influence behavior and mental processes.

Genes

Units of heredity made of DNA that influence traits and biological processes.

DNA

The molecule that carries genetic information.

Chromosome

A DNA-containing structure that carries many genes.

Genotype

An individual's genetic makeup.

Phenotype

Observable characteristics resulting from genes and environmental influences.

Behavior genetics

The study of how genes and environment contribute to behavioral differences.

Heritability

The proportion of variation in a trait within a population associated with genetic differences.

Evolutionary psychology

The study of behavior through the lens of adaptation and natural selection.

Natural selection

The process in which traits that improve survival or reproduction become more common over generations.

Adaptation

An inherited characteristic that helps an organism survive or reproduce.

Twin studies

Research comparing twins to examine genetic and environmental influences on traits.

Identical twins

Twins from one fertilized egg who share nearly all of their DNA.

Fraternal twins

Twins from two separate eggs who are genetically similar to ordinary siblings.

Epigenetics

The study of how environmental factors can affect gene expression without changing DNA.

Neuron

A nerve cell that receives, processes, and transmits information.

Dendrites

Branch-like structures that receive signals from other neurons.

Soma / cell body

The main part of the neuron containing the nucleus and maintaining the cell.

Axon

A long fiber that carries neural impulses away from the cell body.

Myelin sheath

A fatty insulating covering around some axons that speeds neural transmission.

Nodes of Ranvier

Gaps in the myelin sheath where the action potential is regenerated.

Axon terminals

The ends of axons that release neurotransmitters.

Synapse

The junction or small gap between neurons where chemical communication occurs.

Resting potential

The neuron's stable, negatively charged state when it is not firing.

Action potential

A brief electrical impulse that travels down a neuron's axon.

Threshold

The minimum stimulation needed to trigger an action potential.

All-or-none principle

A neuron either fires completely after reaching threshold or does not fire.

Refractory period

A short period after an action potential when the neuron resets and is less able to fire.

Reuptake

The reabsorption of neurotransmitters by the sending neuron.

Excitatory signal

A signal that increases the likelihood that a neuron will fire.

Inhibitory signal

A signal that decreases the likelihood that a neuron will fire.

Neurotransmitter

A chemical messenger released by neurons that affects another neuron, muscle, or gland.

Acetylcholine (ACh)

Neurotransmitter involved in muscle movement, learning, memory, and attention.

Dopamine

Neurotransmitter involved in movement, motivation, reward, attention, and learning.

Serotonin

Neurotransmitter involved in mood, sleep, appetite, and other functions.

Norepinephrine

Neurotransmitter involved in alertness, arousal, attention, and stress.

GABA

The major inhibitory neurotransmitter in the brain.

Glutamate

The major excitatory neurotransmitter in the brain; important for learning and memory.

Endorphins

Natural chemicals involved in pain reduction and pleasure.

Agonist

A substance that mimics or increases a neurotransmitter's effects.

Antagonist

A substance that blocks or decreases a neurotransmitter's effects.

Nervous system

The body's communication network.

Central nervous system (CNS)

The brain and spinal cord.

Peripheral nervous system (PNS)

All nerves outside the brain and spinal cord.

Somatic nervous system

The PNS division involved in voluntary movement and sensory information.

Autonomic nervous system (ANS)

The PNS division controlling involuntary functions.

Sympathetic nervous system

The ANS division that arouses the body for action or stress.

Parasympathetic nervous system

The ANS division that calms the body and supports rest and digestion.

Sensory / afferent neurons

Carry information from sensory receptors toward the CNS.

Motor / efferent neurons

Carry commands from the CNS to muscles and glands.

Interneurons

Neurons within the CNS that connect and process information between neurons.

Reflex

A rapid, automatic response to a stimulus.

Brainstem

Structures connecting the brain to the spinal cord; controls basic survival functions.

Medulla

Controls vital functions such as heartbeat and breathing.

Pons

Helps regulate sleep, arousal, breathing, and communication between brain areas.

Reticular formation

A network involved in arousal, alertness, and attention.

Thalamus

The brain's sensory relay station; routes most sensory information to the cortex.

Cerebellum

Helps coordinate movement, balance, posture, and motor learning.

Hypothalamus

Regulates homeostasis, hunger, thirst, body temperature, and endocrine functions.

Pituitary gland

A major endocrine gland regulated by the hypothalamus; releases hormones affecting growth and other glands.

Limbic system

A group of structures involved in emotion, motivation, memory, and related functions.

Amygdala

Involved in processing emotion, especially fear and threat.

Hippocampus

Important for forming and consolidating new explicit memories.

Cerebral cortex

The brain's outer layer; involved in complex thought, perception, language, and voluntary movement.

Frontal lobe

Involved in planning, decision-making, personality, judgment, and voluntary movement.

Parietal lobe

Processes touch and body sensations and supports spatial processing.

Occipital lobe

Primary region for processing visual information.

Temporal lobe

Involved in hearing, language comprehension, memory, and recognition.

Motor cortex

Area of the frontal lobe controlling voluntary muscle movements.

Somatosensory cortex

Area of the parietal lobe processing touch and body sensations.

Visual cortex

Region in the occipital lobe that processes visual information.

Auditory cortex

Region in the temporal lobe that processes sound.

Broca's area

Region usually in the left frontal lobe involved in producing speech.

Wernicke's area

Region usually in the left temporal lobe involved in language comprehension.

Corpus callosum

Large bundle of fibers connecting the left and right cerebral hemispheres.

Left hemisphere

Generally more involved in language and analytical processing, although functions are distributed across both hemispheres.

Right hemisphere

Generally more involved in spatial and some nonverbal processing, although functions are distributed across both hemispheres.

Lateralization

The specialization of some functions in one cerebral hemisphere more than the other.

Prefrontal cortex

Frontal region involved in planning, judgment, decision-making, and impulse control.