Psychology, 1930-2026

Addiction exhibits pronounced heterogeneity across symptoms, substances, neurobiology, contexts, and treatment outcomes, constituting a persistent challenge for unified theoretical explanation. Addressing this challenge, this work examines how such variability can be systematically understood without reducing addiction to a single social, biological, or psychological mechanism. After outlining the scope of heterogeneity in addiction, the analysis turns to computational models of decision‑making—particularly Redish et al.’s vulnerability framework—as a powerful account of how failures within learning and choice systems generate addictive behavior. It is argued, however, that decision‑making models alone are insufficient unless they account for the contextual conditions in which choices are made. In response, an extended vulnerability framework is developed in which addictive behavior emerges when action selection becomes constrained by contextual and choice‑based vulnerabilities over time. This framework is then linked to precision medicine approaches, which naturally operationalize heterogeneity through individualized diagnosis and treatment. The work concludes by identifying limits of the framework and directions for future research, proposing vulnerability as a unifying lens through which addiction’s complexity can be understood.

Public reactions to athlete misconduct, particularly involving performance-enhancing drug (PED) use, play a critical role in shaping perceptions of fairness, legitimacy, and accountability in sport. While prior research has focused largely on athletes’ internal experiences, less is known about how external observers evaluate such violations. The present study examined how punishment source (sports league vs. legal court system), punishment severity (mild vs harsh), and athlete gender (male vs. female) influe public perception of athlete misconduct. In a 2 x 2 x 2 between-subjects experimental design, participants (N = 607) were randomly assigned to read a vignette describing a professional basketball player who tested positive for PEDs, with variations across the three manipulated factors. Participants then reported their perceptions of punishment fairness, institutional legitimacy, sympathy toward the athlete, and negative emotional reactions. Results indicated that punishment severity was a key driver of evaluations with harsher punishments generally associated with higher perceived fairness and legitimacy, but lower sympathy and forgiveness. Punishment source also influenced perceptions, with legal punishments often viewed as more legitimate but eliciting stronger negative emotional responses. Effects of athlete gender were more limited, though some patterns suggested a difference in moral evaluation. Additionally, individual differences in sports investment moderated responses, such as highly invested participants showed more leniency and reduced negative evaluations. These findings contribute to a broader understanding of how contextual and individual factors shape moral judgments in sport, highlighting the importance of both institutional context and personal investment in shaping public responses to ethical violations.

Why and how do individuals experience fatigue when doing repetitive motor tasks, specifically with timing tasks such as musical rhythms? Previous research into motor fatigue involving tasks without large amounts of physical exertion supports the idea that fatigue is accrued by a breakdown of the surrounding muscles. However, a separate alternative theory of fatigue, the expected value of control theory, involves fatigue accruing from a perceived value of the task and of task-switching, and this has yet to be studied in the motor domain. Three groups of participants (N = 120 total, 40 each) performed a repetitive temporal rhythm-like finger tapping task for 8 minutes, then a 5-minute break, then two testing trials. The groups differed in engagement level of the stimuli presented, but had the same motor task. Results showed that within-trial fatigue was similar across groups but mostly negligent overall, with post-rest gains not presenting in a way consistent with fatigue buildup throughout the study. This is most likely due to the study being too short and not physically demanding enough for participants to experience fatigue as expected. Results also showed that participants increased vigor over time, which is also not consistent with expected fatigue. Future research needs to be conducted to induce more fatigue and be able to evaluate fatigue difference with engagement manipulation.

With the growing use of ChatGPT and Gemini Large Language Models in professional settings, ensuring that they make fair and non-biased decisions has become increasingly important. This thesis aims to examine whether these Large Language Models display any discriminatory behavior when playing the Investor Trust Game with players of different demographic backgrounds, and how their behavior compares with that of human participants. In this Trust Game, the amount of hypothetical money allocated by the Large Language Models and human participants directly reflects the level of trust placed in the coded players. The race and gender of the coded players will be manipulated in order to observe any potential biases which may be held by the Large Language Models and human participants.

Keywords: Large Language Model (LLM), Biases, Demographic, Investor Trust Game

Caregivers scaffold their children’s word learning in many ways, including by adjusting their behavior to engage their children’s attention and fine-tuning their speech to meet their children’s current knowledge levels. How exactly caregivers make decisions about what type of words they want their children to learn is less clear. The current study examines how caregivers select object categories for their children to learn and whether their choices help their children learn new words. To test this question, English-learning two-year-olds learned words from four different categories (i.e., animals, vehicles, toys, food) in an eye-tracking study. In one condition, caregivers selected the categories for each word their children heard, while in the other condition, these words were instead randomly selected. We found that children did not learn more effectively when their caregivers chose the order and frequency of object categories. Caregivers primarily reasoned that their decisions were based on their children’s interests, despite mostly choosing a diverse approach (e.g., one of each category). Additionally, we found that children’s reaction time was significantly quicker for categories of higher interest and that children with a larger vocabulary size and a larger pre-existing knowledge of words in the target category were slightly more accurate in word learning. Our findings suggest that, in pedagogical settings where the goal is for their children to learn new words, caregivers predominantly motivate their choices based on their perception of their children’s interests but choose to expose their children to a diverse selection of words. Overall, our study provides an introductory exploration of the process of caregivers’ decision-making about their children’s word learning.

Psychologists and behavioral scientists have long established the relationships between trust and discretion within institutions, yet none have applied such theories to the prosecutorial discretion established in sentencing policies. The present research seeks to understand if people’s preferences for prosecutorial discretion in sentencing policies may be impacted by their overall trust in the criminal justice system. People do not passively observe policies, instead, they engage in a sensemaking process to try and understand the policymaker’s intentions, and what kind of decision they should make as a result. Such a sensemaking process is often triggered by trust. People also tend to prefer discretion to be used either conservatively or leniently, and both uses have their own set of benefits and risks. Additionally, the way discretion is exercised impacts how people perceive the person with the discretionary power and if they trust them. As such, I hypothesize that when people have low trust in the criminal justice system, they prefer prosecutors to have less discretion in sentencing decisions. Yet, when people have high trust in the criminal justice system, they will prefer that prosecutors have more discretion over sentencing. Across three experimental studies, results consistently established that people with low trust in the criminal justice system preferred prosecutors to have limited discretion, while people with higher trust in the criminal justice system preferred prosecutors to have more complete discretion. Study 1 established the correlational relationship between trust and prosecutorial discretion, across different types of crimes of varying severity. Study 2 experimentally manipulated trust across six different conditions. Study 3 expanded upon Study 2 by also experimentally manipulating trust across the same six conditions, but participants were told that if a prosecutor had limited discretion, the prosecutor had to give the maximum sentence. Participants in decreased trust conditions still preferred limited discretion, even though that meant prosecutors had to sentence the most punitive option. These results have several crucial implications for the criminal justice system and policymakers, and future research should continue to explore the intricacies of the relationship between trust and prosecutorial discretion.

Do infants explore the world merely to understand it, or are they also driven by something deeper, a fundamental desire to be the one who acts upon it? This thesis examines whether 16- to 18-month-old infants are intrinsically motivated to experience agency, defined as the ability to produce contingent outcomes through their own actions, distinct from a motivation to gain information about causal structure. Using a within-subjects design conducted remotely via Zoom, infants pressed a spacebar to interact with an on-screen button in two counterbalanced conditions. In the contingent condition, each press immediately triggered a sound and visual feedback. In the non-contingent condition, identical stimulation occurred on a preprogrammed schedule independent of the infant's actions. If infants are primarily information-seekers, they should press more when outcomes are unpredictable. If motivated by agency, they should press more when their actions reliably cause effects. A pilot study (n = 9) provided preliminary directional support, with six of nine infants pressing more in the contingent condition. In the ongoing Experiment 1 (n = 36 of 40), preliminary data shows infants pressing more in the contingent condition (M = 22.26) than the non-contingent condition (M = 14.97). These findings suggest instead that the experience of causing effects in the world is intrinsically rewarding from early in development. Confirmatory analyses will be conducted upon completion of the full sample.

When trauma history is introduced as mitigating evidence in criminal proceedings, it may simultaneously reduce perceptions of blame and heighten fears of future dangerousness. This study investigated whether providing jurors with information about both a defendant's trauma history and the treatability of trauma-related conditions could shift perceptions of culpability, sentencing, and reoffense likelihood. An online sample of 372 adults participated in a mock jury task. We predicted that trauma information, when presented with treatability information, would reduce culpability, sentencing, and reoffense as compared to without. We found that trauma information reduced culpability and increased reoffense predictions, treatability information partially counteracted the aggravating effect on reoffense when trauma was known, and neither independent variable affected sentencing. These findings underscore the importance of pairing trauma evidence with treatability information in forensic testimony.

This paper examines self-censorship in higher education and how it affects students. While universities promote free inquiry and open discussion, research shows that many students and professors choose not to express their opinions, especially on controversial topics. Drawing on studies and psychological theories such as the spiral of silence and groupthink, this paper explores why self-censorship occurs and how it is shaped by social and academic environments. It argues that fear of judgment and social isolation play a key role in limiting open discussion. The paper also considers how this environment can affect students’ learning, confidence, and ability to engage with different perspectives. Overall, the evidence suggests that self-censorship is a widespread issue and has real consequences, pointing to the need for more open but still respectful discussion in academic settings.

Individuals make preconceived judgments about whether they have the ability or desire to complete a task prior to completing it. A novice will opt for learning to play Mary had a little lamb over learning Rhapsody in Blue. The need to identify a desirable level of difficulty for motor learning is important to promote engagement, enjoyment and longevity in motor skill development. However, we don't know what makes something difficult to learn or what causes one motor task to seem much harder than the next, even when the task is nearly identical. Previous literature suggests that you must perform the task first to determine the desirable level of difficulty, however this can be costly and dangerous. This study explores if people can make an accurate similarity and difficulty judgment for motor learning, and whether this metacognitive assessment of motor learning is accurate to predict performance. I examine how metacognitive judgements of task similarity and difficulty influence performance, if there is an optimal task dissimilarity for optimal learning and whether people know their own desirable level of difficulty when motor learning during a test case scenario. I do this by asking participants to judge the difficulty in different motor sequences that would be analogous to playing a short melody on a piano. I examine if the participants' internal estimates and metacognitive judgments can predict their performance. I found participants are unable to reliably identify similarities between motor sequences and therefore cannot gauge task difficulty from their similarity scores. Instead, participants can reliably gauge task difficulty using execution time. These findings support previous findings from Wilson and Colleagues (2018) and Bjork & Bjork (2020) that there is a desirable level of difficulty, where there is a harmony between difficulty rating and task duration.

This paper explores how family-related motivational factors influence the long-term sustainability of necessity-driven entrepreneurial ventures, specifically in Ipoh, Malaysia. While entrepreneurship is often associated with innovation and opportunity, a significant number of individuals pursue this path out of necessity due to unemployment, limited job access, or financial hardship. These entrepreneurs, especially those motivated to support their families, may experience emotional and psychological dynamics that differ significantly from those of opportunity-driven entrepreneurs.

Using the frameworks of Self-Determination Theory (SDT) and Expectancy Theory, this study examines how family obligation shapes motivation, resilience, and perceived business sustainability. A mixed-methods design was employed, including surveys, semi-structured interviews, and in-person observations with 13 necessity-driven food entrepreneurs operating small, family-run businesses. Measures focused on family motivation, resilience, entrepreneurial identity, and perceived long-term sustainability.

The findings suggest that family-related motivation is a strong driver of persistence, with most participants reporting that financial responsibility toward family members motivates them to continue their business despite challenges. However, results also indicate that this form of motivation does not uniformly lead to long-term sustainability. Entrepreneurs who reported high family obligation but low autonomy or emotional support were more likely to rely on persistence driven by pressure rather than internal fulfillment. In contrast, those who demonstrated higher levels of autonomy, stronger entrepreneurial identity, and supportive family relationships showed greater resilience and confidence in sustaining their businesses over time.

Overall, the study highlights that while family motivation can initiate and sustain necessity-driven entrepreneurship, its long-term effectiveness depends on the extent to which it is internalized and supported by autonomy and emotional resources. These findings contribute to a more nuanced understanding of motivation in constrained socioeconomic contexts and suggest that sustainable entrepreneurship is not solely driven by necessity, but by the quality and structure of underlying motivational forces.

Anxiety is a pervasive challenge among undergraduate students, particularly during high-stress academic periods such as midterm examinations. This study examined the effects of two cognitive reappraisal techniques - Construal and Repurpose - on undergraduate anxiety levels. Additionally, the role of peer social influence in the transmission of emotion regulation strategies was investigated through the manipulation of the proportion of trained individuals within each group. Thirty-two Princeton University Undergraduates were assigned to reappraisal conditions (Construal or Repurpose) or a Control group, and further divided into High (3 trained) and Low (2 trained) proportion conditions based on the number of trained peers within each discussion group. Participants completed pre-, post-, and follow-up questionnaires assessing anxiety levels, predicted and observed grades, stress management ability, perceived grade importance, group connectedness, and discussion usefulness across three timepoints: before, immediately after, and two weeks following the group discussion session conducted over Zoom. Despite null ANOVA findings, descriptive trends indicated that Construal conditions demonstrated the most consistent reductions in anxiety across timepoints compared to Repurpose conditions. Findings suggest that intuitive, accessible reappraisal strategies, such as Construal may be more effectively transmitted through peer social influence and more beneficial in fostering group cohesion alongside emotion regulation adoption. Future research engaging with larger samples, longer follow-up periods, and more direct measures of social influence is needed to build on these preliminary findings.

The study of episodic memory is an intricate yet fundamental aspect of human cognition. This idea is supported by individuals suffering from a system malfunction–either due to physical damage as a result of neuropathology (e.g. medial temporal lobe damage) or a circuit level disruption of the system in healthy individuals (episodic retrieval inhibition under high cognitive load). The data underlying the former instance (memory inhibition resulting from physical damage) is more clear cut, however, understanding the breakdown among individuals with no apparent damage has been more of a challenge. In the existing literature, the breakdown of episodic memory retrieval often coincides with situations that induce high cognitive load–moments that exhaust our limited amount of cognitive resources (e.g. police interrogation, student exams, etc.), however, it is unknown as to why this occurs. In this literature review, we argue that the mechanistic breakdown of episodic memory retrieval under high cognitive load may come as a result of a theta-gamma oscillatory coupling dysfunction–a known mechanism for episodic memory retrieval. In support, individuals suffering from neurological or psychiatric diseases with known episodic memory retrieval deficits (e.g. Alzheimer’s disease, schizophrenia, temporal lobe epilepsy), provide evidence of a theta-gamma coupling dysfunction. Cognitive load also seems to have a direct effect on the inhibition of theta-gamma coupling, as an increase in load has been shown to cause shifts in phase coherence, an excitatory-inhibitory circuit imbalance, and an initial increase in coupling that is followed by a decrease after the load reaches a threshold. While there is evidence to suggest a relationship between high cognitive load and theta-gamma coupling dysfunction, future studies are necessary to examine the relationship between cognitive load and theta-gamma coupling directly. Key words: episodic memory, theta-gamma coupling, cognitive load, phase coherence

Current research extensively explores the buffering role of social support in response to adversity. However, less attention has been given to the conditions under which social support is mobilized including when adversity occurs, who provides the support, or what type of support is exchanged. In the current research, we examine how past adversity and recent stress relate to support-seeking and support receiving across family and friend networks and different types of social support (i.e. emotional, informational, practical, and financial). Using longitudinal data from participants in a low- to middle-income community (n = 385) collected at baseline and a first follow-up survey, we assess how past adversity and recent stress influence social network responses to a recent stressor. Results indicate that recent stress is unrelated to support-seeking but is associated with greater support-receiving from family. In contrast, past adversity predicts reduced support-seeking from friends and is unrelated to support-receiving. These findings highlight the importance of distinguishing between recent stress and past adversity and the consequences adversities may have on social support. Future research should focus on addressing the potential mechanisms between adversity and social support. Additionally, future interventions aimed at reducing stigma may provide valuable support for those with higher instances of adversities when support-seeking.

The way we feel—and how we manage those feelings—likely starts at home. Indeed, researchers have begun charting how both cultures and parents shape emotion regulation habits. In particular, individuals from East Asian cultures report that their parents use more authoritarian parenting styles, which are characterized by strict power structures, and also report greater use of expressive suppression (inhibiting emotional expression) to regulate their own emotions. In contrast, individuals from Western cultures report that their parents use greater authoritative parenting styles (characterized by less strict power structures and an emphasis on warm support) and report less use of expressive suppression as an emotion regulation strategy. Studies also link being raised in authoritative households with greater use of cognitive reappraisal (changing how one thinks about a situation to change how one feels). However, evidence for associations between culture and cognitive reappraisal is mixed, and no study has directly investigated whether parenting styles serve as a generational conduit that connects culture to offsprings’ emotion regulation habits. Here, we test this question in a pre-registered study. We also developed a task-based measure of emotion regulation choice (suppression vs. reappraisal) to test how parenting and culture related to both self-reported and task-evoked regulation strategy use. Adults (N = 380, 50% East Asian, 50% White) completed questionnaires on emotion regulation and parenting, alongside the regulation strategy selection task. In line with prior work, East Asian participants reported greater use of suppression than White participants, and White participants reported greater use of reappraisal than East Asian participants. Furthermore, parenting styles were significantly associated with emotion regulation strategies and partially mediated cultural differences in reappraisal. However, self-report and task measures differed in regards to reappraisal, with both parenting styles positively associated with reappraisal in the self-reported questionnaire but negatively associated in the selection task, stressing the importance of a multi-method assessment. The findings of this study contribute to the current growing body of research that emphasizes how patterns of emotion regulation differ across cultures, suggesting that cultural differences in emotion regulation are partly transmitted through parenting, highlighting the meaningful role that parenting plays in shaping how individuals choose to regulate their emotions. Future research should continue to expand upon these processes across international populations and contexts to better understand how emotion regulation skills develop.

Does reviewing and imagining past failures enhance performance more than reviewing and imagining past successes? This thesis examines the relationship between performance review, positive and negative mental imagery, and its effects on motor performance. Drawing from research on feedback learning theories and athlete video, it looks into how reviewing past performances can lead to simulation, which presumably eventually has effects on motor performance. There has been a wide range of studies on mental imagery as a whole and how it is used in so many aspects of brain function, but the extent of how negative and positive imagery affects motor performance is limited. To determine the effects of film review and positive and negative mental imagery, a qualitative questionnaire and quantitative experiment of an arbitrary motor task is used to accomplish the goal of this experiment. This dual approach experiment provides insight into real life scenarios and data from a simple motor task. In all, the study looks to determine how positive and negative mental imagery, influenced by reviewing film on past performance, affects motor performance within people. The main goal of this study is to evaluate the very limited understanding of the benefits of negative mental imagery enhancement on motor performance through error learning.

Recent studies indicate that the effectiveness of interpersonal emotion regulation (IER) varies across genders; women often derive added emotional benefits from regulating through social interactions, whereas men tend to derive little to no added emotional benefits compared to regulating on their own. In this thesis, we examined whether language—specifically the words that people use when regulating their emotions—could explain gender differences in the effectiveness of interpersonal emotion regulation within certain gendered interpersonal contexts. We aimed to answer three exploratory questions: (1) How do female and male linguistic patterns differ in interpersonal emotion regulation when supporting a female or male friend? (2) How do female and male support quality differ in interpersonal emotion regulation when supporting a female or male friend? (3) How do linguistic patterns differentially predict support quality for women and men? We explored these questions through an online study. Participants (N = 493) read a hypothetical scenario of a person venting about a romantic breakup. Participants were then asked to imagine the person as their closest female or male friend and provide an emotional support response. A separate participant pool (N = 162) rated the efficacy of each response, based on three dimensions: warmth, feeling better, and feeling understood. Analyses tested (1) whether linguistic patterns differ systematically as a function of participant gender, target gender, and/or the interaction between these factors (2) whether support quality differs systematically as a function of participant gender, target gender, and/or the interaction between these factors (3) whether the relationship between linguistic patterns and support quality differs as a function of participant gender. By integrating linguistic and emotional measures, this project aims to provide new insights into how gender and language interact to shape the effectiveness of interpersonal emotion regulation. Understanding these dynamics will not only advance our understanding of emotion regulation but also promote more gender-inclusive models of social support.

What does it take to live a good life? Although it is considered healthy to down-regulate negative emotions, one context in which people can benefit from approaching uncomfortable emotions is when pursuing eudaimonic goals (i.e., goals that involve achieving personal growth, acting in line with values, and finding meaning in life). Such “contrahedonic instrumental emotion regulation” (i.e., choosing to feel bad to reach specific goals) may be particularly important in adolescence, a stage of life where people actively develop their sense of self and personal values. Here, we examine this question in the context of music, a highly naturalistic source of emotion. We ask: Do adolescents use negative music to pursue eudaimonic goals, and if so, how does this habit relate to mental health? We hypothesized that (i) adolescents would be more likely than adults to choose negative music to pursue eudaimonic goals, (ii) individuals with higher levels of internalizing symptoms would be more likely to choose negative music to pursue eudaimonic goals, and (iii) this relationship would be moderated by age. We first established that the stimuli in our task evoked the intended emotions and goals with a pilot study (N = 60, aged 13 to 30). For the main study, participants (ages 13 to 30, N = 53) performed a music selection task where they were asked how useful they believed 12 songs (3 happy, 3 sad, 3 angry, 3 calm) would be in preparing them for two scenarios with a clear eudaimonic goal. In line with our first hypothesis, (i) we found that younger participants perceive negative music as more useful in eudaimonic scenarios compared to older participants. However, (ii) higher internalizing symptoms were associated with lower perceived usefulness of negative music in eudaimonic contexts. Finally, (iii) perceived usefulness of negative music was more strongly associated with internalizing symptoms in older participants. These findings support prior work showing that negative emotions can serve context-specific functions, while also highlighting that their perceived utility for promoting growth may vary across development.

Emotions shape cognition, motivation, and decision-making behavior in many ways. While prior research has linked integral (naturally occurring) climate emotions to climate engagement, little experimental work has tested whether experimentally inducing incidental emotional states in a context independent of climate change shifts climate policy support. In the present study, participants completed an autobiographical writing task to induce a hope, fear, or neutral state. We examined the resulting support for various climate mitigation policies, hypothesizing that hope induction would increase support for proactive policies while fear induction would increase support for regulatory policies based on their action tendencies. We also explored whether these effects vary by political identity and climate beliefs, which are more stable and contain emotionally rich information, unlike the isolated and transient emotional states induced in the study. Emotion induction successfully shifted self-reported emotions in the intended directions; however, it had little effect on overall policy support, which was instead consistently predicted by pre-existing climate beliefs and political identity. Policy support ratings for Democrats were largely unaffected by emotion, potentially due to ceiling effects in climate belief and policy support. Exploratory analyses revealed that among Republicans, a hope state increased support for a ban on the purchase of new gas or diesel cars relative to fear and neutral conditions, possibly reflecting a misattribution of positive feelings to the policy judgment and greater cognitive flexibility under hope. Overall, these results indicate that stable political identity and climate beliefs, rather than transient incidental emotions, are the primary drivers of climate policy support, while incidental emotion states demonstrate small, policy-specific effects. Keywords: emotions, climate policy support, political identity, climate beliefs

Climate change attribution norm misperceptions (i.e., inaccurate beliefs about what other people think regarding the link between climate change and extreme weather) are an important but still understudied way that partisan media may be contributing to polarization around climate change. This study builds on previous research (Nichols et al., 2025) by looking at how different sequences of Fox News hurricane clips shape these misperceptions among both Democrat and Republican viewers. Participants (n = 927) were randomly assigned to watch one of three Fox-labeled sequences consisting of five clips: a fully conservative sequence, a “mixed-middle” sequence (where a liberal clip was inserted in the middle of four conservative clips), or a “mixed-end” sequence (where the liberal clip was inserted after four conservative clips). Misperceptions of Republican, Democrat, and overall American climate attribution norms were measured as the difference between respondents’ perceptions of each group’s likelihood of attributing hurricanes to climate change and that group’s actual self-reported attribution. Misperceptions of Republican norms were the key outcome of interest as Fox News serves as an identity-relevant cue for Republicans. Across all sequence conditions, both Democrats and Republicans consistently underestimated the climate attribution norms of all three groups, and, contrary to hypotheses, the mixed sequences did not reduce misperceptions of Republican norms for either party. However, sequence effects were observed in Republican respondents’ perceptions of Democrat and American norms, where the mixed sequences were associated with reduced underestimation. Overall, these findings suggest that a single ideologically inconsistent clip is not enough to correct partisan norm misperceptions, and highlight the need for more research on how partisan media shapes how people understand others’ climate attitudes.