Glossary of Key Terms
Definitions of key terms from behavioral psychology, motivation science, and positive psychology used throughout the Activation Science research summaries.
The following definitions are provided to support readers who may be encountering these terms for the first time. Each definition aims to capture the core meaning as used in the behavioral science literature referenced throughout this site. For more complete treatments, consult the cited primary sources in our research summaries.
Attentional Bias The tendency for perception to be influenced by recurring thought patterns, such that individuals are more likely to notice stimuli consistent with their current cognitive focus. In practical terms, someone experiencing negative mood states will more readily notice negative events, while deliberate attentional training can shift this bias toward positive or growth-related cues. Research on attentional bias modification suggests that where we direct our attention shapes our experienced reality in measurable ways.
Autonomy (SDT) One of the three basic psychological needs identified by Self-Determination Theory. Autonomy refers to the experience of volition and self-endorsement in one's actions -- the sense that behavior is self-chosen and congruent with one's values, rather than coerced or externally controlled. Autonomy does not mean independence or isolation; rather, it means acting with a sense of willingness and personal ownership. Autonomy satisfaction is consistently associated with greater persistence, wellbeing, and intrinsic motivation.
Behavioral Activation A therapeutic approach, originally developed for the treatment of depression, that emphasizes re-engaging with valued activities as a mechanism for improving mood and breaking cycles of withdrawal and avoidance. Behavioral activation operates on the principle that action precedes motivation rather than following from it. Outside clinical contexts, the core insight -- that small behavioral steps generate the motivational states traditionally thought to be their prerequisites -- has informed a range of applied frameworks.
Broaden-and-Build Theory A theory proposed by Barbara Fredrickson positing that positive emotions serve an evolutionary function by broadening an individual's momentary thought-action repertoire and building durable personal resources over time. Unlike negative emotions, which narrow attention and behavior toward specific survival responses, positive emotions expand awareness, encourage exploration, and foster the development of social, intellectual, and psychological resources. The theory predicts that positive emotional experiences create upward spirals of increasing wellbeing and adaptive functioning.
Cognitive Reappraisal A form of emotion regulation in which an individual reinterprets the meaning of an emotion-eliciting situation in order to change its emotional impact. For example, reframing a setback as a learning opportunity rather than a failure. Cognitive reappraisal is generally considered a more adaptive emotion regulation strategy than suppression, as it modifies the emotional response at its source rather than merely inhibiting its expression. Research consistently links habitual use of reappraisal with better emotional wellbeing and interpersonal functioning.
Competence (SDT) One of the three basic psychological needs in Self-Determination Theory. Competence refers to the experience of effectiveness and mastery in one's interactions with the environment -- the sense that one can produce desired outcomes and manage challenges. Competence need not involve objective expertise; it is the subjective experience of capability and growth that matters. Competence satisfaction supports intrinsic motivation and is undermined by environments that are excessively controlling, overly challenging, or devoid of feedback.
Effect Size A quantitative measure of the magnitude of a research finding, independent of sample size. While statistical significance tells you whether an effect likely exists, effect size tells you how large that effect is. Common metrics include Cohen's d (where 0.2 is considered small, 0.5 medium, and 0.8 large) and correlation coefficients. Effect sizes are essential for evaluating the practical significance of research findings, as even statistically significant results may reflect trivially small effects when samples are very large.
Ego Depletion The hypothesis, proposed by Roy Baumeister and colleagues, that self-control draws on a limited resource that becomes temporarily exhausted through use, much like a muscle fatiguing during exercise. Under this model, exercising willpower on one task reduces the capacity for self-control on subsequent tasks. While influential, the ego depletion model has faced significant replication challenges in recent years, and the field has moved toward more nuanced accounts of self-regulatory fatigue that emphasize motivation, beliefs about willpower, and task perception rather than a simple resource model.
Hedonic Adaptation The well-documented tendency for individuals to return to a relatively stable baseline level of happiness following both positive and negative life events. Also known as the "hedonic treadmill," this phenomenon explains why major positive changes (a raise, a new relationship, a move) tend to produce smaller and shorter-lived increases in life satisfaction than people expect. Hedonic adaptation has significant implications for wellbeing interventions, suggesting that sustained happiness is more likely to arise from ongoing engagement in valued activities than from the attainment of fixed outcomes.
Helper's High A colloquial term for the positive emotional and physiological states reported by individuals following acts of helping or kindness toward others. Research suggests that prosocial behavior activates neural reward systems and is associated with the release of endorphins and oxytocin. The phenomenon has been documented across age groups and cultures, and longitudinal evidence suggests that regular engagement in prosocial behavior predicts sustained improvements in mood, life satisfaction, and even physical health markers.
Implementation Intentions A self-regulatory strategy involving the formation of specific if-then plans that link situational cues to goal-directed responses (e.g., "If it is 7:00 AM, then I will walk for ten minutes"). Developed by Peter Gollwitzer, implementation intentions have been shown to significantly increase the likelihood of goal-directed behavior by automating the initiation of action in response to environmental cues. Their effectiveness is amplified when paired with goals that are self-concordant -- that is, aligned with personal values.
Intrinsic Motivation Motivation arising from genuine interest, enjoyment, or personal satisfaction in an activity, rather than from external rewards, pressures, or contingencies. Intrinsically motivated behavior is pursued for its own sake and is characterized by curiosity, engagement, and a sense of vitality. Self-Determination Theory identifies intrinsic motivation as the most autonomous and self-determined form of motivation, and extensive research links it to greater persistence, creativity, and psychological wellbeing compared to extrinsic motivation.
Knowledge-Action Gap The persistent discrepancy between what individuals know they should do and what they actually do. Despite having accurate information about beneficial behaviors (exercise, nutrition, stress management), most people fail to act consistently on that knowledge. Research suggests that the knowledge-action gap is not primarily an information problem but a motivation and implementation problem, pointing to the need for behavioral frameworks that address action initiation rather than simply providing more information.
Meta-Analysis A statistical method for combining the results of multiple independent studies addressing the same research question. By pooling data across studies, meta-analyses provide more precise estimates of effect sizes and can identify patterns that individual studies lack the statistical power to detect. Meta-analyses occupy a high position in the evidence hierarchy because they synthesize findings across different samples, methodologies, and contexts, reducing the influence of any single study's idiosyncratic features. See our guide on How to Read This Research for more on interpreting meta-analytic findings.
Micro-Habit A behavioral strategy involving the reduction of desired behaviors to their smallest possible form -- typically requiring two minutes or fewer to complete. Based on research in habit formation and behavioral activation, micro-habits leverage the principle that consistency of initiation matters more than magnitude of effort for establishing durable behavioral patterns. By reducing the activation threshold to a near-trivial level, micro-habits bypass many of the self-regulatory barriers that derail conventional behavior change programs.
Positive Psychology A branch of psychology, formalized by Martin Seligman and Mihaly Csikszentmihalyi around 2000, that focuses on the scientific study of strengths, wellbeing, and optimal human functioning rather than exclusively on pathology and dysfunction. Positive psychology investigates topics including happiness, flow, character strengths, gratitude, and resilience. While sometimes criticized for being insufficiently rigorous or overly optimistic, the field has produced a substantial body of empirical work on interventions that reliably enhance wellbeing in non-clinical populations.
Prosocial Behavior Voluntary behavior intended to benefit others, including acts of helping, sharing, comforting, and cooperating. Research consistently demonstrates that engaging in prosocial behavior produces measurable benefits for the actor as well as the recipient, including enhanced positive affect, greater life satisfaction, and reduced depressive symptoms. The wellbeing benefits of prosocial behavior appear to be particularly robust when acts are varied, self-chosen, and perceived as meaningful by the individual performing them.
Relatedness (SDT) The third basic psychological need in Self-Determination Theory. Relatedness refers to the experience of meaningful connection with others -- feeling cared for, understood, and significant to other people. Relatedness is satisfied not merely by social contact but by interactions characterized by warmth, mutual regard, and a sense of belonging. Satisfaction of the relatedness need is associated with greater wellbeing, more effective self-regulation, and deeper internalization of social values.
Self-Compassion A construct developed by Kristin Neff involving three core components: self-kindness (treating oneself with warmth rather than harsh self-judgment during difficulty), common humanity (recognizing that suffering and imperfection are shared human experiences rather than isolating personal failures), and mindfulness (holding painful experiences in balanced awareness rather than over-identifying with them). Research links self-compassion to greater emotional resilience, reduced anxiety and depression, and -- contrary to intuitive concerns -- maintained rather than diminished motivation and personal standards.
Self-Concordance The degree to which personal goals align with an individual's enduring interests, values, and sense of self. Developed by Kennon Sheldon and Andrew Elliot, the self-concordance model predicts that goals pursued because they reflect genuine personal values (rather than external pressures or introjected obligations) generate greater sustained effort, higher rates of attainment, and more wellbeing upon completion. Self-concordance serves as a critical moderator of the effectiveness of many goal-pursuit strategies.
Self-Determination Theory (SDT) A comprehensive theory of human motivation developed by Edward Deci and Richard Ryan, positing that optimal motivation and wellbeing require the satisfaction of three basic psychological needs: autonomy, competence, and relatedness. SDT distinguishes between autonomous motivation (driven by interest, values, or personal importance) and controlled motivation (driven by external rewards, punishments, or internalized pressure), with extensive evidence demonstrating that autonomous motivation produces superior outcomes across domains including education, healthcare, work, and personal goal pursuit.
Self-Discrepancy Theory A theory proposed by E. Tory Higgins that examines the emotional consequences of perceived gaps between different self-representations: the actual self (who you are), the ideal self (who you would like to be), and the ought self (who you believe you should be). Discrepancies between the actual and ideal self are associated with dejection-related emotions (sadness, disappointment), while discrepancies between the actual and ought self are associated with agitation-related emotions (anxiety, guilt). The theory has implications for goal-setting and values clarification, as it highlights the importance of pursuing goals aligned with one's ideal self rather than externally imposed obligations.
Self-Efficacy An individual's belief in their capacity to execute the behaviors necessary to produce specific outcomes. Developed by Albert Bandura, self-efficacy theory holds that confidence in one's ability to perform a given task is a powerful predictor of whether one will attempt the task, how much effort will be invested, and how long persistence will continue in the face of difficulty. Self-efficacy is domain-specific (one can have high self-efficacy in one area and low in another) and is built primarily through mastery experiences, vicarious observation, and social persuasion.
Upward Spiral A concept drawn from Broaden-and-Build Theory describing the self-reinforcing cycle in which positive emotions broaden awareness and behavioral flexibility, which in turn builds personal resources, which in turn generates further positive emotions. Upward spirals contrast with the downward spirals characteristic of depression and anxiety, in which negative emotions narrow attention, reduce behavioral engagement, and erode coping resources. Research suggests that even modest, consistent positive emotional inputs can initiate upward spirals that compound over time.
Values Elicitation A structured process through which individuals identify and articulate their core personal values -- the qualities and principles that matter most deeply to them. Unlike goal-setting, which focuses on specific outcomes, values elicitation focuses on directions and qualities of action. Research in acceptance and commitment therapy and self-concordance theory demonstrates that explicit awareness of personal values enhances goal selection, increases autonomous motivation, and improves the coherence of an individual's overall goal system. Values elicitation is distinguished from values clarification by its emphasis on discovery rather than education.