Plain-language definitions
Glossary
Quick definitions with routes into the deeper evidence, examples, and limitations.
Affective forecasting
Predicting how one will feel after a future event, often with errors about intensity or duration.
Read the full article →Anchoring
The influence of an initial value on later numerical estimates, even when the starting point is weakly informative.
Read the full article →Attachment theory
A framework describing how repeated experiences with caregivers shape expectations about support and close relationships.
Read the full article →Attribution and context
A tendency in some settings to explain others’ behavior through dispositions while underweighting situational constraints.
Read the full article →Availability heuristic
Estimating likelihood or frequency partly from how easily examples come to mind.
Read the full article →Barnum effect
Rating vague, broadly applicable personality descriptions as uniquely accurate.
Read the full article →Bystander effect
In some emergencies, an individual may be less likely to help when other bystanders are present.
Read the full article →Change blindness
Difficulty noticing substantial changes when they coincide with an interruption or visual disruption.
Read the full article →Classical conditioning
Learning that one event predicts another, allowing a previously neutral cue to elicit a response.
Read the full article →Cognitive dissonance
Psychological discomfort or motivational tension arising from inconsistent beliefs, choices, or actions.
Read the full article →Confirmation bias
The tendency to seek, interpret, and remember information in ways that fit an existing belief.
Read the full article →Correlation and causation
Correlation describes variables changing together; causation claims that changing one produces change in another.
Read the full article →Dunning–Kruger effect
A debated pattern in which low performers may have difficulty accurately evaluating their own performance.
Read the full article →Emotion regulation
Processes that influence which emotions occur, when they occur, and how they are experienced or expressed.
Read the full article →Empathy
A family of capacities for understanding or sharing another person’s emotional state.
Read the full article →Framing effect
A shift in preference caused by presenting equivalent information in different ways.
Read the full article →Gestalt grouping principles
Principles describing how visual elements tend to be organized into coherent wholes.
Read the full article →Habit formation
The development of context-linked action tendencies that become easier to initiate with repetition.
Read the full article →Halo effect
A favorable impression in one area can color judgments of unrelated qualities.
Read the full article →Hedonic adaptation
Emotional responses to changed circumstances often diminish as those circumstances become familiar.
Read the full article →Hindsight bias
After learning an outcome, seeing it as more predictable than it was beforehand.
Read the full article →Illusion of transparency
Overestimating how clearly one’s private thoughts and emotions are visible to others.
Read the full article →In-group favoritism
Giving preferential evaluation or treatment to people categorized as part of one’s own group.
Read the full article →Inattentional blindness
Failing to notice a visible, unexpected object while attention is engaged elsewhere.
Read the full article →Loss aversion
In many choices, a loss relative to a reference point weighs more heavily than an equal-sized gain.
Read the full article →Measurement quality
The reliability and validity of observations used to represent a psychological construct.
Read the full article →Mere exposure effect
Repeated exposure can increase liking for initially neutral stimuli under some conditions.
Read the full article →Misinformation effect
Post-event information can alter later reports about an experienced event.
Read the full article →Obedience
Behavior performed in response to an authority’s direct instruction.
Read the full article →Observational learning
Learning by attending to others’ actions and their consequences.
Read the full article →Operant conditioning
Learning in which consequences change the future probability of behavior.
Read the full article →Overconfidence
Confidence that is higher than the accuracy or precision of one’s judgments warrants.
Read the full article →Peak–end rule
Retrospective evaluations can be disproportionately influenced by an experience’s most intense point and its ending.
Read the full article →Placebo and nocebo effects
Changes in symptoms or outcomes associated with expectations, context, and learning around treatment.
Read the full article →Procrastination
Voluntarily delaying an intended action despite expecting the delay to be worse overall.
Read the full article →Publication bias
The scientific record can become distorted when some results are more likely to be published than others.
Read the full article →Reconstructive memory
The idea that remembering is an active reconstruction shaped by stored traces, knowledge, and the retrieval situation.
Read the full article →Replication and cumulative evidence
Replication examines whether a finding can be observed again under similar or deliberately varied conditions.
Read the full article →Representativeness heuristic
Judging probability by similarity to a prototype, sometimes underweighting base rates.
Read the full article →Retrieval practice
Actively recalling information can strengthen later retention more than additional passive exposure alone.
Read the full article →Selective attention
The prioritization of some information for processing while other available input receives less attention.
Read the full article →Self-concept
The organized beliefs and knowledge a person holds about who they are.
Read the full article →Self-determination theory
A theory proposing that autonomy, competence, and relatedness support high-quality motivation and well-being.
Read the full article →Serial-position effects
Items near the beginning and end of a sequence are often remembered better than items in the middle.
Read the full article →Social comparison
Evaluating oneself partly through comparison with other people.
Read the full article →Social facilitation
The presence of others can improve performance on well-practiced tasks and impair difficult or unfamiliar ones.
Read the full article →Social loafing
People sometimes exert less individual effort when contributions are pooled and difficult to identify.
Read the full article →Social proof
Using other people’s behavior as information about what is appropriate or likely correct.
Read the full article →Spacing effect
Learning episodes distributed over time generally support longer-term retention better than the same time massed together.
Read the full article →Spotlight effect
Overestimating how much other people notice one’s appearance or behavior.
Read the full article →Stress appraisal
The evaluation of whether a situation threatens resources and whether coping options are available.
Read the full article →Stroop effect
Slower or less accurate color naming when a word’s meaning conflicts with its ink color.
Read the full article →Sunk cost effect
Continuing because of resources already spent even when only future costs and benefits should guide the choice.
Read the full article →Understanding effect size
Effect size describes the magnitude of a difference or relationship, complementing evidence about uncertainty.
Read the full article →Working memory
A limited system for temporarily maintaining and manipulating information in service of a task.
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