Abstract How does testosterone influence decisions and choice-related neural computations in competitive environments? To address this question, we administered testosterone or placebo to female participants (n = 54) in a double-blind, randomized design. Following drug treatment, participants competed in a dot estimation task that manipulated opponent status (lower, equal, or higher) and outcome feedback (win or loss), after which they decided whether to compete against the same opponent again. All participants adjusted their behavior based on opponent status and outcome feedback. Participants who received testosterone, however, showed significantly greater sensitivity to outcome feedback: they were more willing to compete after winning and less willing after losing, and made those decisions faster - suggesting that testosterone increases the weighting of immediate, salient outcome information in competitive decision-making. At the neural level, a network comprising ventral striatum, vmPFC, bilateral TPJ and ACC processed outcome-related signals during the feedback period. Critically, neural prediction analyses at the trial-level revealed that activity in left ventral striatum and TPJ predicted subsequent decisions to compete, but only in participants who received testosterone. The direction of these effects mirrored the behavioral results: striatal activity amplified the tendency to re-compete after winning, whereas TPJ activity predicted renewed competition after losing. Together, these findings demonstrate that testosterone biases competitive decisions by amplifying the influence of outcome-related activity in reward and social cognition circuits.

The cognitive reflection test (CRT) measures reliance on intuitive thinking versus deliberate reasoning and predicts important real-world outcomes. Prior research has suggested that testosterone administration impaired CRT performance, but follow-up studies produced null results. To provide a rigorous test, we conducted a large, preregistered, double-blind, placebo-controlled experiment, unprecedented in size, with 1,000 adult men, as part of an adversarial collaboration. Participants received a single dose of intranasal testosterone or placebo, completed the CRT, and rated their confidence level. We found an insignificant treatment effect on the CRT, with the point estimate in the opposite direction of the original hypothesis (βLOGIT = 0.118, 95% confidence interval (CI) = [-0.099, 0.335]). In a second primary test, we found a significant negative treatment effect on confidence (βLOGIT = -0.329, 95% CI = [-0.558, -0.100]), which is also the opposite of our prediction. Our findings challenge earlier claims about testosterone's cognitive effects and highlight the importance of high-powered replications. Long-term or developmental testosterone effects remain potentially important but difficult to study.

A burgeoning area of research has begun to uncover a wide range of potential neurological and psychological correlates of hormonal contraceptive (HC) use. Yet there remains a limited understanding of the underlying mechanisms for how HC use alters aspects of neurobiology and related behavioral outcomes. Uncovering these processes has the potential for new discovery in the field of behavioral neuroendocrinology, particularly in the complex interplay between steroid hormone subclasses. Although prior research has often focused on the effects of HC use on progestogen and estrogen disruption, basal and reactive androgens and cortisol may also be significantly impacted by HC use and serve critical functions throughout the brain and body. We discuss important background information on the synthesis and function of three steroid hormones - testosterone, dehydroepiandrosterone-sulfate (DHEAS), and cortisol, review prior research showing how HC use is related to circulating (basal) and reactive levels, and provide sample data on salivary levels from our own research. The combined evidence shows that HC use, specifically of the OC pill, is associated with significantly reduced total, free, and salivary androgens, increased total cortisol in blood but not saliva, and a blunted salivary cortisol response to social stressors. Limited evidence provides initial indication that the specific estrogen and progestin compounds in HC formulas may differentially impact steroid hormone levels. Finally, we discuss the mechanisms by which HCs alter steroid hormone levels, the potential implications of these effects on brain and behavior outcomes, and considerations for future research.

When interacting with others in unfamiliar sociocultural settings, people need to learn the norms guiding appropriate behavior. The present research investigates an individual difference that helps this kind of learning: stress reactivity. Interactions in an unfamiliar sociocultural setting are stressful, particularly when the actor fails to follow its rules. Although stress is typically considered a liability, more stress-reactive individuals may be more motivated to improve and, thus, quicker to learn these rules. Consistent with this idea, a pilot study found that people genetically inclined to stress reactivity, as computed by a genetic profile score across 59 single-nucleotide polymorphisms on 10 different genes, learned unfamiliar sociocultural norms from experiential feedback at a faster rate (i.e., exhibited a greater increase in accuracy across trials). Study 1 found that participants with higher acute cortisol reactivity in response to a physical stressor were faster at learning unfamiliar sociocultural norms. Study 2 conceptually replicated these results using a self-report measure of dispositional stress reactivity. Study 3 found that self-reported dispositional stress reactivity similarly predicted the rate of learning in a sociocultural task and a nonsocial task. Study 4 provided evidence for the underlying mechanism-participants higher on dispositional stress reactivity experienced more stress early in the sociocultural norm learning task, which predicted faster learning overall and lower stress later on in the task. These findings indicate that more stress-reactive individuals get more stressed out from the negative feedback that they receive in social interactions in unfamiliar settings, which motivates them to learn the relevant norms. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

This chapter reviews the social neuroscience literature on human aggression, including research in molecular genetics, neuroendocrinology, neuroimaging, and social psychology. The findings indicate that (1) the amygdala and orbitofrontal cortex (OFC) are critical components of the neural circuitry of aggression; (2) the serotonergic system plays a crucial role in modulating aggression; (3) testosterone and cortisol influence aggression, likely through modulation of the amygdala and orbitofrontal cortex; and (4) environmental risk factors (media violence) and protective factors (emotion regulation) may modulate aggression via alterations in these biological systems and neural circuits. We end the chapter by discussing new directions for future research.

There is conflicting evidence on whether testosterone affects economic preferences such as risk taking, fairness, and altruism, with most evidence coming from correlational studies or small testosterone administration studies. To credibly test this hypothesis, we conducted a large-scale, preregistered, double-blind randomized controlled trial with 1,000 male participants-10 to 20 times larger than typical prior studies. Participants were randomly allocated to receive a single dose of either placebo or intranasal testosterone, and carried out a series of economic tasks capturing social preferences, competitiveness, and risk preferences. We find no evidence of a treatment effect for any of our nine primary outcome measures, and no strong evidence of an association between basal salivary testosterone and economic preferences within men. These results fail to conceptually replicate previous high-impact publications reporting positive findings in smaller samples, calling into question the idea that short-term testosterone fluctuations are important drivers of men's economic preferences. Our results do not rule out the possibility that different effects might emerge under alternative dosages, administration protocols, or task timings, or that behavioral effects differ between men and women. The potential for developmental or long-term effects of testosterone also remains an open question for future research, though such effects are ethically challenging to investigate experimentally in humans.

Steroid hormones such as testosterone are theorized to predict financial trading success. However, studies have reported inconsistent associations between hormones and financial trading performance and have largely overlooked interactions between multiple hormone systems and psychological factors that may influence hormones during trading. One such psychological state, mindfulness, is posited to influence hormone levels and improve trading performance. However, the hormonal pathway between mindfulness and financial trading performance remains untested. To address this gap, we examined the extent to which a brief mindfulness intervention influenced changes in testosterone and cortisol levels, and how these hormonal changes jointly predicted performance in a financial trading task in financial traders. Relative to a control group, traders who underwent the mindfulness intervention exhibited a reduction in cortisol levels and an elevation in testosterone levels. This dual-hormone profile - decreased cortisol and increased testosterone - was linked to better trading performance: elevated testosterone levels predicted higher earnings among traders whose cortisol levels decreased but not among traders whose cortisol levels increased. These findings offer initial insights into mindfulness-induced hormonal changes among traders, with downstream benefits for financial performance. We propose recommendations for further research on the endocrine pathways underlying mindfulness' influence on financial performance.

Sex/gender differences in personality associated with gender stereotyped behavior are widely studied in psychology yet remain a subject of ongoing debate. Exposure to testosterone during developmental periods is considered to be a primary mediator of many sex/gender differences in behavior. Extensions of this research has led to both lay beliefs and initial research about individual differences in basal testosterone in adulthood relating to "masculine" personality. In this study, we explored the relationships between testosterone, gender identity, and gender stereotyped personality attributes in a sample of over 400 university students (65 % female assigned at birth). Participants provided ratings of their self-perceived masculinity and femininity, resulting in a continuous measure of gender identity, and a set of agentic and communal personality attributes. A saliva sample was also provided for assay of basal testosterone. Results showed no compelling evidence that basal testosterone correlates with gender-stereotyped personality attributes or explains the relationship between sex/gender identity and these attributes, across, within, or covarying out sex assigned at birth. Contributing to a more gender diverse approach to assessing sex/gender relationships with personality and testosterone, our continuous measure of self-perceived masculinity and femininity predicted additional variance in personality beyond binary sex and showed some preliminary but weak relationships with testosterone. Results from this study cast doubt on the activational testosterone-masculinity hypothesis for explaining sex differences in gender stereotyped traits and within-sex/gender variation in attributes associated with agency and communality.

Stress is an established risk factor for negative health outcomes. Salivary cortisol and testosterone concentrations increase in response to acute psychosocial stress. It's crucial to reduce stress for health and well-being through evidence-based interventions. Body-mind interventions such as meditation and Tai Chi have shown reduced cortisol levels but mixed results in testosterone concentration after stress. To address this research gap, we conducted a pilot randomized controlled trial to examine the modulating effects of a short-term (seven 20-minute sessions) mindfulness meditation on testosterone and cortisol in response to acute stress. Using one form of mindfulness meditation - Integrative Body-Mind Training (IBMT) and an active control-relaxation training (RT), we assessed salivary cortisol and testosterone concentrations at three stages of stress intervention - rest, stress, and an additional 20-min IBMT or RT practice. We found increased cortisol and testosterone concentrations after acute stress in both groups, but testosterone rise was not associated with cortisol rise. Moreover, an additional practice immediately after stress produced higher testosterone concentrations in the IBMT group than the RT group, whereas cortisol concentration increased in the RT group than in the IBMT group at the same time point. These findings indicate that brief mindfulness intervention modulates a dual-hormone profile of testosterone and cortisol in response to acute stress presumably via the co-regulation of hypothalamus-pituitary-adrenal and hypothalamus-pituitary-testicular axes.

Objective A goal of behavioral neuroendocrinology is to understand how basal hormone levels relate to behavior. Studies of human participants sometimes measure self-reported personality traits, in addition to or instead of direct behavioral observation. Although personality traits often predict their respective behaviors, whether personality explains hormone-behavior relationships remains unclear. Methods We obtained data from eight previous studies (total N = 985) that examined baseline testosterone and cortisol as predictors of status-relevant behavior (competitiveness, dominance, risk-taking, aggression, affiliation, and social status). We tested whether the previously reported hormone-behavior relationships are mediated by self-reported personality traits (e.g., trait dominance, prestige, extraversion). As a secondary research question, we also tested whether trait dominance moderated the testosterone-behavior relationships. Results As expected, self-reported personality traits often predicted status-relevant behaviors, but there was little evidence that traits also correlated with basal testosterone or the testosterone × cortisol interaction. Across all eight studies, personality traits did not significantly mediate hormone-behavior relationships. Indeed, the effect sizes of the hormone-behavior relationships were robust to the inclusion of personality traits as covariates. Further, we did not find strong or consistent evidence that trait dominance moderates the testosterone-behavior association. Conclusion Results suggest that basal testosterone and cortisol predict status-related behavior independent of self-reported personality. We discuss how these results may have broader implications for the physiological mechanisms by which testosterone and cortisol influence behavior, a process that could be unconscious and automatic. We also discuss alternative explanations, limitations, and future directions.

Previous research indicates that higher testosterone levels are related to increased aggressive and dominant behaviors, particularly in males. One possible mechanism for these hormone-behavior associations could involve threat perception. However, the causal influence of testosterone on men's recognition of threatening facial expressions remains unknown. Here, we tested the causal effect of exogenous testosterone on men's sensitivity to facial threat by combining a psychophysical task with computational modeling. We administered a single dose (150 mg) of testosterone or placebo gel to healthy young men (n = 120) in a double-blind, placebo-controlled, between-participant design. Participants were presented with morphed emotional faces mixing anger/fear and neutral expressions and made judgments about the emotional expression. Across typical regression analysis, signal detection analysis, and drift diffusion modeling, our results consistently showed that individuals who received testosterone (versus placebo) exhibited a lower perceived sensitivity to angry facial expressions. But we observed no significant effects of testosterone administration on fearful facial expressions. The findings indicate that testosterone attenuates sensitivity to facial threat, especially angry facial expressions, which could lead to a misestimation of others' dominance and an increase in one's own aggressive and dominant behaviors.

Intergroup competitions such as democratic elections can intensify intergroup polarization and conflict. Partisan attitudes toward the elected leader can also shift from before to after an election, but the biology underlying these attitudinal shifts remains largely unknown. An important factor could be the hormone testosterone, which is theorized to fluctuate during competition and to influence status seeking. In a naturalistic study of 113 registered voters, we measured changes in testosterone levels and attitudes toward the winner of the 2012 US Presidential Election. We found that supporters of the losing candidate (Mitt Romney) showed acute increases in testosterone levels compared to supporters of the winner (Barack Obama) on the evening of Election Day. Supporters of the losing candidate also demonstrated flatter diurnal testosterone slopes on Election Day that persisted up to two days after the election. Furthermore, greater increases in acute testosterone levels and flatter diurnal slopes among supporters of the losing candidate were associated with less positive evaluations of the winning candidate. These testosterone-moderated attitudinal shifts observed in the days after the election showed a directionally similar pattern with a weaker effect size six months later. Finally, we confirmed that the main results were robust to alternative data analytic choices using multiverse specification curve analysis. The findings from this paper suggest that hormonal responses to large-scale intergroup competitions may shape how we perceive our elected leaders, shedding light on the biology of intergroup relations.

**Objective**: Hormones are often conceptualized as biological markers of individual differences and have been associated with a variety of behavioral indicators and characteristics, such as mating behavior or acquiring and maintaining dominance. However, before researchers create strong theoretical models for how hormones modulate individual and social behavior, information on how hormones are associated with dominant models of personality are needed. Although there have been some studies attempting to quantify the associations between personality traits, testosterone, and cortisol, there are many inconsistencies across these studies. **Methods**: In this registered report, we examined associations between testosterone, cortisol, and Big Five personality traits. We aggregated 25 separate samples to yield a single sample of 3,964 (50.3% women; 27.7% of women were on hormonal contraceptives). Participants completed measures of personality and provided saliva samples for testosterone and cortisol assays.**Results**: The results from multi-level models and meta-analyses revealed mostly weak, non-significant associations between testosterone or cortisol and personality traits. The few significant effects were still very small in magnitude (e.g. testosterone and conscientiousness: r = -0.05). A series of moderation tests revealed that hormone-personality associations were mostly similar in men and women, those using hormonal contraceptives or not, and regardless of the interaction between testosterone and cortisol (i.e., a variant of the dual-hormone hypothesis). **Conclusions**: Altogether, we did not detect many robust associations between Big Five personality traits and testosterone or cortisol. The findings are discussed in the context of biological models of personality and the utility of examining heterogeneity in hormone-personality associations.

The challenge hypothesis makes specific predictions about the association between testosterone and status-seeking behaviors, but the findings linking testosterone to these behaviors are often inconsistent. The dual-hormone hypothesis was developed to help explain these inconsistencies. Specifically, according to this hypothesis, testosterone's association with status-seeking behavior depends on levels of cortisol. Here, we (1) describe the dual-hormone hypothesis in relation to the challenge hypothesis; (2) review recent studies that tested the dual-hormone hypothesis as well as meta-scientific evidence of heterogeneous dual-hormone findings across studies; (3) discuss potential explanations for this heterogeneity, including methodological considerations, contextual factors, and individual differences; and (4) provide recommendations for new work aimed at testing and extending the dual-hormone hypothesis.

We review the literature on the relationships between cortisol, stress and various forms of social status, concluding that cortisol (and stress) is typically elevated when one chronically lacks, or may soon lose, status. Moreover, cortisol is lower when status is higher as long as that status is stable, enhances one’s sense of control, and does not also substantially increase one’s responsibilities. Because cortisol is both an output (stress indicator) and input (cause of behavioral inhibition), this low cortisol may be both a cause and consequence of stable status. Altogether, the cortisol-status relationship depends not just on one’s status but on what that status means for the individual (e.g., How frequent and severe are stressors? Does one feel a sense of control? Does one need to be vigilant and deferential?).

Testosterone is associated with behaviors such as aggression and sensation seeking as well as behavioral disorders such as impulse-control disorders including drug addiction and eating disorders, but to what degree and how testosterone affects cognition and decisionmaking remains unclear. Given the role of testosterone in mating and reproduction, Nave, Nadler, Zava, and Camerer (2017) suggested that the “facilitation of rapid intuitive responses by testosterone could be biologically adaptive in contexts in which reproductive success depends on instincts (e.g., during copulation) and when responding slowly might be especially costly (e.g., during physical challenges)” (p. 1404). This led them to hypothesize that testosterone biases decision-making away from reflective and deliberate responses and toward rapid and intuitive ones, thereby elucidating one potential mechanism by which testosterone might cause behaviors and behavioral disorders. To study their hypothesis, Nave et al. conducted a single experiment (N = 243) in which they randomly administered either exogenous testosterone or placebo to participants and then measured their performance on the Cognitive Reflection Test (CRT), a simple three-item assessment of intuitive versus deliberate decision-making (Frederick, 2005). Each CRT item has an intuitive but incorrect response with which most people respond; discerning the correct response requires one to inhibit this intuitive response and to perform deliberate but easy calculations. For example, one item reads,

Transient shifts in testosterone occur during competition and are thought to positively influence dominance behavior aimed at enhancing social status. However, individual differences in testosterone reactivity to status contests have not been well-studied in relation to real-time expressions of competitive behavior among men and women. This research tests the association between changes in endogenous testosterone levels during competition and performance in terms of competitive endurance. Participant sex, social presence, and relative status outcomes (e.g., winning vs. losing) are tested as moderators of this relationship. In two studies, men and women (total N = 398) competed in the competitive will task (timed weight-holding) either individually or in the presence of an opponent (Study 1) or as a team with and without the presence of a competitor team (Study 2). Results showed a positive relationship between testosterone reactivity and performance for men, particularly those who won or ranked highest among their group - with increasing testosterone predicting better performance and decreasing testosterone predicting worse performance. For women, the effect only emerged among individuals who competed in dyads and lost. In Study 2, an exploratory mediation analysis revealed that individual differences in trait dominance predicted both testosterone reactivity to competition and task performance, with testosterone reactivity (moderated by sex and status outcome) partially explaining the direct relationship between dominance-related traits and behavior. Our goal was to examine testosterone reactivity in relation to real-time competitive effort and highlight the potential role of this relationship in explaining how individual differences in trait dominance produce competitive behavior.

This chapter reviews literature having to do with the social-behavioral neuroendocrinology of competition, dominance, and status hierarchies in humans. After defining these terms, their importance, and everyday relevance, the chapter discusses the major research findings that suggest a bidirectional influence between these social behaviors and the steroid hormones cortisol and testosterone. Specifically, the association between cortisol and social rank and cortisol’s reactivity to social challenges are discussed. Further, this chapter discusses research that tests the predictions that basal testosterone is related to status-motivated behavior, that testosterone levels are transiently altered during contests for status, and that these changes function to promote subsequent status-seeking behavior. Noting the nuance of these findings, the personality and context factors that appear to moderate testosterone–status relationships are highlighted. Finally, this chapter includes both a new theoretical model for the testosterone–social status relationship that captures this complexity and, in closing, summarizes promising areas of future research.

Testosterone has been theorized to direct status-seeking behaviors, such as competitive decision-making. However, individual differences in basal cortisol and cues that signal an opponent’s status (an opponent’s gender or a prior win/loss in a competition) may moderate testosterone’s relationship with status-seeking behavior. This experiment (n = 115) examines the causal effect of testosterone treatment on men’s competitive behavior before and after receiving relative performance feedback (i.e. win/loss feedback) in mixed-gender math competitions, while also accounting for the moderating role of endogenous basal cortisol. Men given testosterone treatment who had high basal cortisol showed an increased tendency to compete against female opponents and avoid competition against male opponents; men given testosterone treatment who had low basal cortisol showed the opposite pattern (OR = 2.54, 95%CI [1.47, 4.37], p<.001). After providing trial-by-trial feedback, men given testosterone who had high basal cortisol re-entered competitions against low status opponents (prior losers) and avoided competition against high status opponents (prior winners); men given testosterone who had low basal cortisol preferred to re-enter competitions against high status opponents (prior winners) and avoid low status opponents (prior losers; OR = 10.21, [1.84, 56.54], p = .008). These results provide experimental support for a context-dependent dual hormone hypothesis: Testosterone flexibly directs men’s competitive behavior contingent on basal cortisol levels and cues that signal an opponent’s status.