AP Psychology Vocabulary Terms with Definitions

Empiricism

The view that knowledge comes from experience and that science should rely on observation and experimentation.

Structuralism

An early school of psychology that used introspection to explore the structure of the human mind.

Functionalism

A school of psychology focused on how mental and behavioral processes function and enable organisms to adapt.

Behaviorism

The view that psychology should be an objective science and study behavior without reference to mental processes.

Humanism

A perspective emphasizing personal growth, self-actualization, and free will.

Cognitive Psychology

The study of mental processes such as perception, thinking, memory, and language.

Biopsychosocial Approach

An integrated perspective that incorporates biological, psychological, and social-cultural levels of analysis.

Nature vs. Nurture

The debate over the relative contributions of biology and experience to human development.

Basic vs. Applied Research

Basic research aims to increase knowledge; applied research solves practical problems.

Operational Definition

A statement of the procedures used to define research variables.

Independent Variable (IV)

The factor that is manipulated in an experiment.

Dependent Variable (DV)

The outcome that is measured in an experiment.

Control Group

The group not exposed to the treatment; serves as a comparison.

Experimental Group

The group exposed to the treatment.

Confounding Variable

A variable that may interfere with the relationship between the IV and DV.

Placebo Effect

Experimental results caused by expectations alone.

Double-Blind Procedure

Neither the participants nor the researchers know who is receiving the treatment.

Correlation vs. Causation

Correlation shows a relationship, not a cause-effect link.

Ethical Guidelines (APA)

Principles to ensure the ethical treatment of research participants.

Neuron

A nerve cell that transmits information.

Dendrite

The part of a neuron that receives messages.

Axon

The extension of a neuron that sends impulses.

Synapse

The gap between neurons.

Action Potential

A neural impulse.

Neurotransmitters

Chemical messengers that cross synapses.

Dopamine

Involved in movement, learning, attention, and emotion.

Serotonin

Affects mood, hunger, sleep, and arousal.

Acetylcholine (ACh)

Enables muscle action, learning, and memory.

Central Nervous System (CNS)

The brain and spinal cord.

Peripheral Nervous System (PNS)

Connects the CNS to the body.

Sympathetic Nervous System

Arouses the body in stressful situations.

Parasympathetic Nervous System

Calms the body.

Amygdala

Linked to emotion.

Hippocampus

Involved in memory.

Hypothalamus

Regulates hunger, thirst, and body temperature.

Frontal Lobe

Involved in decision-making and planning.

Parietal Lobe

Processes sensory information.

Occipital Lobe

Processes visual information.

Temporal Lobe

Processes auditory information.

Corpus Callosum

Connects the two brain hemispheres.

Plasticity

The brain’s ability to change.

Endocrine System

Glands that secrete hormones.

Absolute Threshold

The minimum stimulation needed to detect a stimulus.

Difference Threshold (JND)

The minimum difference a person can detect.

Weber’s Law

The principle that to be perceived as different, two stimuli must differ by a constant percentage.

Signal Detection Theory

Predicts how we detect a signal amid noise.

Sensory Adaptation

Diminished sensitivity due to constant stimulation.

Top-Down Processing

Perception driven by cognition.

Bottom-Up Processing

Analysis of the stimulus begins with the sensory receptors.

Transduction

Conversion of sensory input into neural signals.

Selective Attention

Focusing on one particular stimulus.

Gestalt Principles

Rules that describe how the human eye perceives visual elements.

Depth Perception

The ability to see in 3D.

Monocular Cues

Depth cues available to each eye separately.

Binocular Cues

Depth cues that require both eyes.

Classical Conditioning

Learning through association.

Unconditioned Stimulus (UCS)

A stimulus that naturally triggers a response.

Unconditioned Response (UCR)

The natural response to the UCS.

Conditioned Stimulus (CS)

A previously neutral stimulus that now triggers a response.

Conditioned Response (CR)

The learned response to the CS.

Operant Conditioning

Learning through rewards and punishments.

Positive Reinforcement

Adding a pleasant stimulus.

Negative Reinforcement

Removing an unpleasant stimulus.

Positive Punishment

Adding an unpleasant stimulus.

Negative Punishment

Removing a pleasant stimulus.

Schedules of Reinforcement

Patterns that define how often a behavior is reinforced.

Shaping

Reinforcing behaviors closer to the desired behavior.

Latent Learning

Learning that occurs but is not apparent until needed.

Observational Learning

Learning by watching others.

Modeling

Imitating observed behavior.