Changes in testosterone mediate the effect of winning on subsequent aggressive behaviour

The intersection between alexithymia, testosterone reactivity, and coparenting in fathers predicts child's prosocial behavior

The development of prosocial skills in children is a key predictor of long-term social, cognitive, and emotional functioning. However, the role of fathers' psychological characteristics in fostering prosocial development, including during the prenatal period, and the mechanisms underlying their influence, remain relatively unexplored. This study aimed to examine whether a higher tendency of alexithymia, a difficulty to identify and verbalize emotions, in expectant fathers predicts prosocial behavior of two-year-old toddlers through the quality of coparenting and whether greater testosterone increase during a stressful parenting task moderates this indirect effect. A sample of 105 couples and their children was tracked longitudinally starting from the third trimester of pregnancy (T1), at three months (T2), and at two years postnatally (T3). Using self-report questionnaires, fathers reported on alexithymia (T1) and mothers and fathers reported on coparenting quality (T2). Additionally, fathers provided saliva samples before and after engaging in a stressful parenting task (the Inconsolable Doll Task) to measure testosterone reactivity (T1). Children's prosocial behavior was observed during an out-of-reach task (T3). A moderated mediation analysis using structural equation modeling showed that higher levels of alexithymia pre-birth predicted lower coparenting quality three months after birth, which in turn predicted lower prosocial behavior of two-year-old children, but only among fathers with mean or high testosterone increases. This study illuminates a potential mechanism by which fathers' alexithymia and testosterone reactivity forecast their toddlers' prosocial behavior.

Effects of testosterone enanthate on aggression, risk-taking, competition, mood, and other cognitive domains during 28 days of severe energy deprivation

RATIONALE

Behavioral effects of testosterone depend on dose, acute versus sustained formulation, duration of administration, personality, genetics, and endogenous levels of testosterone. There are also considerable differences between effects of endogenous and exogenous testosterone.

OBJECTIVES

This study was the secondary behavioral arm of a registered clinical trial designed to determine if testosterone protects against loss of lean body mass and lower-body muscle function induced by a severe energy deficit typical of sustained military operations.

METHODS

Behavioral effects of repeated doses of testosterone on healthy young men whose testosterone was reduced by severe energy deficit were examined. This was a double-blind, placebo-controlled, between-group study. Effects of four weekly intramuscular injections of testosterone enanthate (200 mg/week, N = 24) or matching placebo (N = 26) were evaluated. Determination of sample size was based on changes in lean body mass. Tasks assessing aggression, risk-taking, competition, social cognition, vigilance, memory, executive function, and mood were repeatedly administered.

RESULTS

During a period of artificially induced, low testosterone levels, consistent behavioral effects of administration of exogenous testosterone were not observed.

CONCLUSIONS

Exogeneous testosterone enanthate (200 mg/week) during severe energy restriction did not reliably alter the measures of cognition. Study limitations include the relatively small sample size compared to many studies of acute testosterone administration. The findings are specific to healthy males experiencing severe energy deficit and should not be generalized to effects of other doses, formulations, or acute administration of endogenous testosterone or studies conducted with larger samples using tests of cognitive function designed to detect specific effects of testosterone.

No evidence for relationship between paternal post-partum depressive symptoms and testosterone or cortisol in first-time fathers

Male life history strategies are regulated by the neuroendocrine system. Testosterone (T) and cortisol regulate male behaviors including parenting and facilitate managing tradeoffs at key transitions in development such as first-time fatherhood. Both hormones demonstrate marked fluctuations in the postnatal period, and this presents an opportunity to investigate the role of T and cortisol in postpartum depressive symptoms-comparably less studied in fathers than in mothers in the evolutionary literature. Prior work on depressive symptoms has yet to integrate insights from the "dual hormone hypothesis (DHH)" which has focused on how T and cortisol interact to jointly regulate traits associated with dominance and status-seeking (i.e., mating effort) but has yet to be included in models of parenting effort. In this research, we use secondary data to investigate the relationship between DHH and traits ostensibly opposed to status seeking (i.e., depressive symptoms). First-time fathers (n = 193) provided morning saliva samples 10 months following parturition and reported on the presence of depressive symptoms (BDI-II). Responses were decomposed into three factors: cognitive, affective, and somatic. Using hybrid latent variable structural equation modeling, we did not find evidence that T predicted variability in cognitive, affective, or somatic depressive symptom factors. We found a null effect for cortisol as well. Finally, we could not find evidence that the DHH variable (T × cortisol interaction) predicted any variability in cognitive, affective, or somatic depressive symptoms. While we did not find evidence to support our hypotheses using a secondary data set, this study contributes to research on the neuroendocrinology of depression in fathers. Discussion focuses on the limitations of sample demographics, timing of saliva and self-report collection, and the lack of extant theory specific to paternal postpartum depression.

Excluded and ashamed: Shame proneness interacts with social exclusion and testosterone reactivity to predict behavioral aggression

Exclusion from social relationships is a painful experience that may threaten an individual's status and dominance. The steroid hormone testosterone, which fluctuates rapidly in response to such threats, may be implicated in subsequent behavioral action (e.g., aggressive or prosocial responses) that aims to protect or enhance one's status after exclusion. Past research, however, indicates that the link between acute changes in testosterone and behavior depend on context-relevant individual dispositions. In the context of social exclusion, an individual's level of shame proneness-characterized by a tendency to experience shame and to react submissively-is theoretically relevant to the testosterone-induced aggression relationship but has yet to be examined empirically. Here, men (n = 167) were randomly assigned to be socially included or excluded in the virtual ball-tossing game, Cyberball, after which aggressive behavior was examined using the Point Subtraction Aggression Paradigm (PSAP). Testosterone reactivity was measured via salivary hormone samples collected pre- and post-game. Moderated multiple regression analyses were run to examine the extent to which testosterone reactivity and shame proneness moderated the effect of Cyberball condition on aggression. Results revealed a significant two-way interaction between Cyberball condition and testosterone reactivity, as well as a three-way interaction including shame proneness. For individuals low in shame proneness, exclusion was associated with higher post-cyberball aggression among those who experienced a rise in testosterone but was associated with lower post-cyberball aggression among those who experienced a decrease in testosterone. For individuals high in shame proneness, however, exclusion did not meaningfully affect aggressive responses, regardless of whether they experienced an increase or decrease in testosterone. These findings extend our understanding of the moderating roles of context and disposition on the neuroendocrinology of aggression in social interaction.

The effect of COVID-19 on home advantage in high- and low-stake situations: Evidence from the European national football competitions

The Covid-19 pandemic has significantly altered the way sporting events are observed. With the absence or limited presence of spectators in stadiums, the traditional advantage enjoyed by home teams has diminished considerably. This underscores the notion that the support of home fans can often be considered a key factor of the home advantage (HA) phenomenon, wherein teams perform better in front of their own supporters. However, the impact of reduced attendance on games with higher stakes, as opposed to low-stakes friendly matches, remains uncertain. In this study, we investigate the recently concluded European football championship (EURO 20), wherein several teams had the advantage of playing at home in high-stakes games with only one-third of the stadium capacity filled. Firstly, we demonstrate that the Covid-19 restrictions, leading to reduced fan attendance, resulted in a nearly 50% decrease in HA compared to the HA exhibited by the same teams during the qualification stage preceding EURO 20, even after accounting for team strength. Secondly, we show that while low-stakes friendly matches generally exhibit a smaller overall HA compared to high-stakes games, the absence of fans led to a similar reduction in HA during the low-stakes matches. Utilizing the recently developed Home Advantage Mediated (HAM) model (Bilalić, Gula, & Vaci, 2021, Scientific Reports, 21558), we were able to attribute the reduction in both high- and low-stakes games to poorer team performance, with no significant contribution from referee bias.

Behavioral convergence in defense behaviors in pair bonded individuals correlates with neuroendocrine receptors in the medial amygdala

Monogamous, pair-bonded animals coordinate intra-pair behavior for spatially separated challenges including territorial defense and nest attendance. Paired California mice, a monogamous, territorial and biparental species, approach intruders together or separately, but often express behavioral convergence across intruder challenges. To gain a more systems-wide perspective of potential mechanisms contributing to behavioral convergence across two conspecific intruder challenges, we conducted an exploratory study correlating behavior and receptor mRNA (Days 10 and 17 post-pairing). We examined associations between convergence variability in pair time for intruder-oriented behaviors with a pair mRNA index for oxytocin (OXTR), androgen (AR), and estrogen alpha (ERα) receptors within the medial amygdala (MeA) and the anterior olfactory nucleus (AON), brain regions associated with social behavior. An intruder behavior index revealed a bimodal distribution of intruder-related behaviors in Challenge 1 and a unimodal distribution in Challenge 2, suggesting population behavioral convergence, but no significant correlations with neuroendocrine measures. However, OXTR, AR, and ERα mRNA in the MeA were positively associated with convergence in individual intruder-related behaviors, suggesting multiple mechanisms may influence convergence. Mice could also occupy the nest during intruder challenges and convergence in nest attendance was positively correlated with MeA OXTR. At an individual level, nest attendance was positively associated with MeA ERα. Vocalizations were positively associated with AR and ERα mRNA. No positive associations were found in the AON. Overall, neuroendocrine receptors were implicated in convergence of a monogamous pair's defense behavior, highlighting the potential importance of the MeA as part of a circuit underlying convergence.

Salivary hormone concentrations and technical-tactical performance indicators in beach volleyball: Preliminary evidence

The present study aimed to investigate (i) differences in salivary testosterone and cortisol concentrations before, during, and after simulated beach volleyball match, depending on match outcome (winning vs. losing); (ii) the relationship between technical-tactical performance indicators in beach volleyball and salivary hormonal concentrations (i.e., testosterone, cortisol). We hypothesized (i) salivary testosterone concentrations would be greater in winners and salivary cortisol would be lower; (ii) testosterone would associate with positive technical-tactical performance and cortisol would associate with negative technical-tactical performance. Sixteen athletes participated in the study and were grouped according to the result of a simulated game (winners: n = 8; losers: n = 8). Salivary hormone concentration of testosterone and cortisol were measured by enzyme-linked immunosorbent assay (pre-match, post first set, and post-match), and the coefficient of performance and efficiency were used as technical-tactical performance indicators. Regarding testosterone, there was a large effect size for match outcome after the first set (i.e., Winner vs. Losers) and a moderate effect size for the time in winners (pre-match vs. post-match). Regarding cortisol, there was a moderate effect size of time in losers only (pre-match vs. post-match). Moreover, cortisol pre-match was negatively correlated with the offensive performance (attack performance coefficient: r = −0.541; p = 0.030; attack efficiency: r = −0.568; p = 0.022). In conclusion, the effect of match outcome on testosterone and cortisol levels was moderate in winners and losers, respectively. Moreover, resting cortisol concentration appears to be related to a diminished attack technical-tactical performance. However, larger confirmatory studies are required to confirm these data to corroborate winning increases testosterone levels and/or reduces cortisol in a sporting setting.

Arousal/Stress Effects of "Overwatch" eSports Game Competition in Collegiate Gamers

ABSTRACT

Kraemer, WJ, Caldwell, LK, Post, EM, Beeler, MK, Emerson, A, Volek, JS, Maresh, CM, Fogt, JS, Fogt, N, Häkkinen, K, Newton, RU, Lopez, P, Sanchez, BN, and Onate, JA. Arousal/stress effects of "Overwatch" eSports game competition in collegiate gamers. J Strength Cond Res XX(X): 000-000, 2022-To date, no physical response data are available for one of the most popular eSport games, Overwatch. The purpose of this investigation was to describe the stress signaling associated with competitive Overwatch play and to understand how acute hormonal responses may affect performance. Thirty-two male college-aged gamers (age: 21.3 ± 2.7 years; estimated time played per week: 18 ± 15 hours) completed the study. Subjects were randomly assigned to a 6-player team to compete in a tournament-style match. Salivary measures of cortisol and testosterone were collected immediately before (PRE) and after (POST) the first-round game, with the heart rate recorded continuously during the match. The mean characteristics were calculated for each variable and comparisons made by the skill level. Significance was defined as p ≤ 0.05. There were no differences in measures of salivary cortisol. A differential response pattern was observed by the skill level for testosterone. The low skill group displayed a significant increase in testosterone with game play (mean ± SD, testosterone PRE: 418.3 ± 89.5 pmol·L-1, POST: 527.6 ± 132.4 pmol·L-1, p < 0.001), whereas no change was observed in the high skill group. There were no differences in heart rate characteristics between skill groups. Overall, the average heart rate was 107.2 ± 17.8 bpm with an average max heart rate of 133.3 ± 19.1 bpm. This study provides unique physiological evidence that a sedentary Overwatch match modulates endocrine and cardiovascular responses, with the skill level emerging as a potential modulator.

Beyond sex and aggression: testosterone rapidly matches behavioural responses to social context and tries to predict the future

Although androgens are widely studied in the context of aggression, androgenic influences on prosocial behaviours have been less explored. We examined testosterone's (T) influence on prosocial and aggressive responses in a positively valenced social context (interacting with a pairbond partner) and a negatively valenced context (interacting with an intruder) in socially monogamous Mongolian gerbils. T increased and decreased prosocial responses in the same individuals towards a pairbond partner and an intruder, respectively, both within 30 min, but did not affect aggression. T also had persistent effects on prosocial behaviour; males in which T initially increased prosocial responses towards a partner continued to exhibit elevated prosocial responses towards an intruder male days later until a second T injection rapidly eliminated those responses. Thus, T surges can rapidly match behaviour to current social context, as well as prime animals for positive social interactions in the future. Neuroanatomically, T rapidly increased hypothalamic oxytocin, but not vasopressin, cellular responses during interactions with a partner. Together, our results indicate that T can facilitate and inhibit prosocial behaviours depending on social context, that it can influence prosocial responses across rapid and prolonged time scales, and that it affects oxytocin signalling mechanisms that could mediate its context-dependent behavioural influences.

Reactive vs proactive aggression: A differential psychobiological profile? Conclusions derived from a systematic review

INTRODUCTION

Scholars have established subcategories of aggressive behavior in order to better understand this construct. Specifically, a classification based on motivational underpinnings makes it possible to differentiate between reactive and proactive aggression. Whereas reactive aggression is characterized by emotional lability, which means it is prone to impulsive reactions after provocation, proactive aggression is driven by low emotionality and high levels of instrumentality to obtain benefits. Some authors have conceived these two types as having a dichotomous nature, but others argue against this conceptualization, considering a complementary model more suitable. Hence, neuroscientific research might help to clarify discussions about their nature because biological markers do not present the same biases as psychological instruments.

AIM

The main objective of this study was to carry out a systematic review of studies that assess underlying biological markers (e.g., genes, brain, psychophysiological, and hormonal) of reactive and proactive aggression.

METHODS

To carry out this review, we followed PRISMA quality criteria for reviews, using five digital databases complemented by hand-searching.

RESULTS

The reading of 3993 abstracts led to the final inclusion of 157 papers that met all the inclusion criteria. The studies included allow us to conclude that heritability accounted for approximately 45% of the explained variance in both types of aggression, with 60% shared by both, especially, for overt and physical expression forms, and 10% specific to each type. Regarding allelic risk factors, whereas low functioning variants affecting serotonin transport and monoaminoxidase increased the risk of reactive aggression, high functioning variants were associated with proactive aggression. Furthermore, brain analysis revealed an overlap between the two types of aggression and alterations in the volume of the amygdala and temporal cortex. Moreover, high activation of the medial prefrontal cortex (PFC) facilitated proneness to both types of aggression equally. Whereas stimulation of the right ventrolateral (VLPFC) and dorsolateral (DLPFC) reduced proneness to aggression, inhibition of the left DLPFC increased it. Finally, psychophysiological and hormonal correlates in general did not clearly differentiate between the two types because they were equally related to each type (e.g., low basal cortisol and vagal variability in response to acute stress) CONCLUSIONS: This study reinforces the complementary model of both types of aggression instead of a dichotomous model. Additionally, this review also offers background about several treatments (i.e., pharmacological, non-invasive brain techniques…) to reduce aggression proneness.

Reward Dependence-Moderated Noradrenergic and Hormonal Responses During Noncompetitive and Competitive Physical Activities

The aim of this study was to reveal whether increased reward dependence (RD) plays a role in the catecholamine neurotransmitter release and testosterone hormone regulation during physical activities among healthy trained participants. Twenty-two male participants (mean age: 40.27 ± 5.4 years) participated in this study. Two conditions were constructed, namely, a noncompetitive and a competitive running task (RT), which were separated by a 2-week interval. Urine and blood samples were collected prior to and following the running tasks. Noradrenaline (NA), adrenaline (A), dopamine (D), and their metabolites, vanillylmandelic acid (VMA) and homovanillic acid (HVA), were measured from urine, while testosterone levels were analyzed from blood samples. RD was assessed using the Cloninger's Personality Inventory (PI). Mental health was evaluated using the WHO Well-Being, Beck Depression, and Perceived Life Stress Questionnaires. According to our findings, levels of NA, A, D, VMA, and testosterone released underwent an increase following physical exertion, independently from the competitive condition of the RT, while HVA levels experienced a decrease. However, we found that testosterone levels showed a significantly lower tendency to elevate in the competitive RT, compared with the noncompetitive condition (p = 0.02). In contrast, HVA values were higher in the competitive compared with the noncompetitive condition (p = 0.031), both before and after the exercise. Considering the factor RD, in noncompetitive RT, its higher values were associated with elevated NA levels (p = 0.007); however, this correlation could not be detected during the competitive condition (p = 0.233). Among male runners, the NA and testosterone levels could be predicted to the degree of RD by analyzing competitive and noncompetitive physical exercises.

Castration and emasculation in the middle age. The andrological conundrum of Peter Abelard

   : Peter Abelard (1079 - 1142) is still considered one of the giants of philosophy, theology, and psychology, and the unsurpassed master of dialectical debate. Born in Le Pallet, near Nantes, Abelard became an academic and wandering cleric of great fame, founder of several schools that attracted students from all countries, arousing the admiration of his contemporaries and the profound envy of his colleagues. Around 1115, Abelard became master of the school of the Cathedral of Notre-Dame. Shortly after, the canon Fulbert asked him to take his niece, the equally famous and highly cultured Héloïse d'Argenteuil (1092 ? - 1164), as a pupil. Thus a relationship began, celebrated for centuries to come, characterized by burning sexual and intellectual passion, famous correspondence which will be the archetype of sentimental education and the template of romantic love letters, the birth of a son and consequent marriage, and the cowardly revenge of Fulbert, who, together with a band of servants, mutilated<<those parts of my body with which I had done what was the cause of their pain>>, as Abelard wrote. While this unclear self-description has suggested to contemporaries and to posterity that Abelard was castrated, we aim to question this belief by analyzing in-depth this historical-andrological clinical case to understand if there is any evidence that could suggest that Abelard was instead the victim of an even more brutal punishment: penectomy. Signs and symptoms gleaned from the personal writings and historical perspectives of Abelard and his time are used here to provide a possible answer to a thousand-year-old question: what makes a man … a man? This article is protected by copyright. All rights reserved.

Home advantage mediated (HAM) by referee bias and team performance during covid

The fans' importance in sports is acknowledged by the term 'the 12th man', a figurative extra player for the home team. Sport teams are indeed more successful when they play in front of their fans than when they play away. The supposed mechanism behind this phenomenon, termed Home Advantage (HA), is that fans' support spurs home players to better performance and biases referees, which in turn determines the outcome. The inference about the importance of fans' support is, however, indirect as there is normally a 12th man of this kind, even if it is an opponent's. The current pandemic, which forced sporting activities to take place behind closed doors, provides the necessary control condition. Here we employ a novel conceptual HA model on a sample of over 4000 soccer matches from 12 European leagues, some played in front of spectators and some in empty stadia, to demonstrate that fans are indeed responsible for the HA. However, the absence of fans reduces the HA by a third, as the home team's performance suffers and the officials' bias disappears. The current pandemic reveals that the figurative 12th man is no mere fan hyperbole, but is in fact the most important player in the home team.

Testosterone fluctuations in response to a democratic election predict partisan attitudes toward the elected leader

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.

Development of a single-dose intranasal testosterone administration paradigm for use in men and women

For over two decades, researchers in the field of human social neuroendocrinology have been using single-dose pharmacological challenge protocols to determine the causal effects of testosterone on psychological, behavioural, and neural processes. Most of these single-dose administration studies have so far used (1) single-sex samples and (2) varying modes of testosterone administration (intramuscular, transdermal, sublingual, and intranasal) that produced vastly different dose-response curves. Moreover, whereas studies with male participants increased men's testosterone concentrations within the high normal physiological range, studies with women typically increased testosterone concentrations to supraphysiological levels. The purpose of this study was to develop a single-dose administration protocol using intranasal testosterone that would produce a proportionally similar rise in testosterone for both sexes. We found that an 11 mg intranasal testosterone dose in men and a 0.3 mg dose in women raised testosterone concentrations to the high normal physiological range for each sex, producing similar dose-response dynamics in both sexes. This paradigm will allow researchers to design studies with mixed-sex samples that test physiologically plausible sex differences/similarities in the causal effects of testosterone. It will also provide a replicable protocol to examine the possible adaptive functions of acute increases in testosterone in both sexes.

Low Competitive Status Elicits Aggression in Healthy Young Men: Behavioral and Neural Evidence

Winners are commonly assumed to compete more aggressively than losers. Here, we find overwhelming evidence for the opposite. We first demonstrate that low-ranking teams commit more fouls than they receive in top-tier soccer, ice hockey, and basketball men's leagues. We replicate this effect in the laboratory, showing that male participants deliver louder sound blasts to a rival when placed in a low-status position. Using neuroimaging, we characterize brain activity patterns that encode competitive status as well as those that facilitate status-dependent aggression in healthy young men. These analyses reveal three key findings. First, anterior hippocampus and striatum contain multivariate representations of competitive status. Second, interindividual differences in status-dependent aggression are linked with a sharper status differentiation in the striatum and with greater reactivity to status-enhancing victories in the dorsal anterior cingulate cortex. Third, activity in ventromedial, ventrolateral, and dorsolateral prefrontal cortex is associated with trial-wise increases in status-dependent aggressive behavior. Taken together, our results run counter to narratives glorifying aggression in competitive situations. Rather, we show that those in the lower ranks of skill-based hierarchies are more likely to behave aggressively and identify the potential neural basis of this phenomenon.

Modest Exercise-Induced Increases in Testosterone Concentration Are Not Associated with Mating Strategy Change in Healthy Young Men

Research has demonstrated that increases in testosterone (T) concentration can affect the expression of behaviours and preferences that are typical of high mating effort. However, little research has considered whether such T increases affect mating strategy more generally and whether this is achievable using a physical intervention. In this pilot study, we examined whether exercise-induced changes in T covary with, or predict, changes in male mating strategy. Healthy young men (N = 94) completed a measure of short- and long-term relationship preference, before and after a series of short cycling sprints. Salivary T was measured pre- and post-exercise, along with salivary cortisol (C), which is known to moderate some behavioural effects of T. A significant group-level increase in T was observed, though this was smaller than anticipated (~ 10%, d = 0.27) with substantial intragroup variation. No group-level change in C or mating preferences emerged. Testosterone change did not significantly predict a change in short- or long-term mating preference from baseline, even with inclusion of C change as a moderator. The current findings suggest that modest exercise-induced increases in T concentration have little impact on male mating strategies. Pharmaceutical interventions, which produce larger and more consistent T increases, may be required to observe mating strategy change.

Exogenous testosterone decreases men's sensitivity to vocal cues of male dominance

Assessing dominance is important for effective social interactions, and prior research suggests that testosterone is associated with men's dominance perceptions. The present study tested for a causal effect of exogenous testosterone on men's sensitivity to vocal cues of other men's dominance, an important parameter in male-male competition across species. One hundred and thirty-nine Chinese men received a single dose (150 mg) of testosterone or placebo gel in a double-blind, placebo-controlled, between-participant design. Participants reported their own dominance and judged other men's dominance from voices. Men's dominance sensitivity was significantly weaker in the testosterone group compared to those in the placebo group. Moreover, men's dominance sensitivity was negatively associated with their self-reported dominance in our Chinese sample, consistent with findings from Western populations. These results indicate that exogenous testosterone has a causal effect in decreasing men's dominance sensitivity, consistent with the Challenge Hypothesis, suggesting that the fluctuation of testosterone concentration mediates individuals' behaviors. Additionally, the present study could motivate further work on vocal assessment in the context of competition in humans and other species.

Leader emergence and affective empathy: A dynamic test of the dual-hormone hypothesis

Personal distress is a building block of empathy, yet has received scant attention in studies of individual differences in leadership. We investigate whether the effect of leader emergence on men's distress is influenced by their personalized power motive (p Power) and changes in their testosterone (T) and cortisol (C) levels. In an experiment involving 96 males, p Power modulated the direction and intensity of T change in emergent leaders, with high p-Power leaders showing a more positive T change compared to their low p-Power counterparts. We also conducted a dynamic test of the dual-hormone hypothesis in which participants' changes in T and C interacted to produce differences in personal distress. Contrary to expectations, positive changes in T were associated with increased distress at negative changes in C. Given that high T and low C are associated with leadership, we explain these findings and question the assumption that personal distress represents a shortcoming in leaders.

Reproductive hormone measurement from minimally invasive sample types: Methodological considerations and anthropological importance

Energetic investment in human reproduction has long been recognized as costly, influencing developmental, physiological, and behavioral patterns in males and females. These effects are largely coordinated through the actions of reproductive hormones (eg, testosterone, estradiol, and progesterone). Here, the utility and limitations of minimally invasive sampling techniques are explored, providing a novel perspective on how reproductive hormone measurements can enhance reproductive endocrinology research. Salivary steroid measures are most commonly used, although several dried blood spot and urine assays are also available, and researchers continue to explore the efficacy of other sample types. These relatively simple measures have facilitated the collection of multiple samples from a single participant, allowing researchers to more accurately track the diurnal and cyclical variation exhibited by many reproductive hormones. Ultimately, the ability to collect fine-grained participant data allows biological anthropologists to better test questions central to human reproductive ecology, life history theory, and public health. For example, fieldwork using these techniques suggests that testosterone profile variation across populations is influenced by energetic constraints and reproductive status. Moreover, hormone concentrations shape the development of sex characteristics, with implications for evolutionary questions related to sexual selection. Hormone levels also can be used to identify a range of medical concerns (eg, suppressed hormone production levels linked with psychosocial stress). These findings highlight how minimally invasive collection techniques can be applied to test diverse evolutionary hypotheses and identify important health concerns. Still, more work is needed to standardize collection and laboratory analysis procedures, thereby enabling more direct data comparisons between researchers.

A longitudinal investigation of bidirectional and time-dependent interrelationships between testosterone and training motivation in an elite rugby environment

In sport, testosterone has been positioned as a substrate for motivation with both directional and time dependencies. However, evidence is scarce when considering the complexities of competitive sport and no work has explicitly modeled these dependencies. To address these gaps, we investigated the bidirectional and time-dependent interrelationships between testosterone and training motivation in an elite rugby environment. Thirty-six male athletes were monitored across training weeks before and after eight international rugby matches. Pre-breakfast measures of salivary testosterone and training motivation (1-10 rating) were taken on training, competition, and recovery days (up to 40 tests). Using a continuous-time (CT) model, within-person estimates of autoregressive effects (persistence) and cross-lagged effects (relationships) were derived. A stronger, more persistent temporal association was identified for testosterone than for motivation. Cross-lagged effects verified that training motivation was positively related to testosterone at latter time points (p < 0.001). Discrete-time analyses revealed a non-linear association; increasing in strength from a zero-time lag to peak after 2.83 days (standardized effect = 0.25), before dissipation over longer lagged intervals. The testosterone relationship with ensuing training motivation was also positive, but non-significant. Match effects also appeared (p < 0.001) with a predicted decline in training motivation, but a rise in testosterone, at match onset. In summary, a positive association emerged between within-person fluctuations in self-appraised motivation to train and testosterone concentration in an elite rugby environment. The lagged, non-linear nature of this relationship and match predictions on both outcomes support, and extend, theoretical models linking testosterone and competitive behaviors.

Testosterone reactivity to competition and competitive endurance in men and women

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.

Is testosterone linked to human aggression? A meta-analytic examination of the relationship between baseline, dynamic, and manipulated testosterone on human aggression

Testosterone is often considered a critical regulator of aggressive behaviour. There is castration/replacement evidence that testosterone indeed drives aggression in some species, but causal evidence in humans is generally lacking and/or-for the few studies that have pharmacologically manipulated testosterone concentrations-inconsistent. More often researchers have examined differences in baseline testosterone concentrations between groups known to differ in aggressiveness (e.g., violent vs non-violent criminals) or within a given sample using a correlational approach. Nevertheless, testosterone is not static but instead fluctuates in response to cues of challenge in the environment, and these challenge-induced fluctuations may more strongly regulate situation-specific aggressive behaviour. Here, we quantitatively summarize literature from all three approaches (baseline, change, and manipulation), providing the most comprehensive meta-analysis of these testosterone-aggression associations/effects in humans to date. Baseline testosterone shared a weak but significant association with aggression (r = 0.054, 95% CIs [0.028, 0.080]), an effect that was stronger and significant in men (r = 0.071, 95% CIs [0.041, 0.101]), but not women (r = 0.002, 95% CIs [-0.041, 0.044]). Changes in T were positively correlated with aggression (r = 0.108, 95% CIs [0.041, 0.174]), an effect that was also stronger and significant in men (r = 0.162, 95% CIs [0.076, 0.246]), but not women (r = 0.010, 95% CIs [-0.090, 0.109]). The causal effects of testosterone on human aggression were weaker yet, and not statistically significant (r = 0.046, 95% CIs [-0.015, 0.108]). We discuss the multiple moderators identified here (e.g., offender status of samples, sex) and elsewhere that may explain these generally weak effects. We also offer suggestions regarding methodology and sample sizes to best capture these associations in future work.

Testosterone reactivity is associated with reduced neural response to reward in early adolescence

The marked increase in adolescent reward-seeking behavior has important implications for adaptive and maladaptive development. Reward-seeking is linked to increased testosterone and increased neural responses to reward cues. How acute testosterone changes modulate neural reward systems remains unclear. Based on previous work, adolescents, particularly males, showing an increase in endogenous testosterone reactivity were hypothesized to show increased neural response to reward in ventromedial prefrontal cortex, ventral striatum, and posterior cingulate cortex. Sixty-one healthy adolescents aged 10-13 (38 female, mean age = 12.01 [SD = 1.00]) completed a reward-cue processing task during fMRI. Saliva samples to be assayed for testosterone were collected immediately before and after scanning. Acute testosterone changes were not associated with variation in behavioral performance. Within ventromedial prefrontal and posterior cingulate cortices, increased acute testosterone change was associated with reduced discrimination between rewarded and un-rewarded trials. Results suggest that increasing levels of testosterone may result in reduced attention to/salience of task irrelevant information. In contrast to previous studies that found a positive association between testosterone and neural response to reward, the reward information in the current paradigm was irrelevant to success in task performance. These results are consistent with theoretical conceptualization of testosterone's role in reproduction, which involves a shift in salience to short-term relative to long-term goals. These data further emphasized the need to consider context in the study of hormones; specific behaviors will be up- or down-regulated by a hormone based on the fit of the behavior with the broader contextual goal being orchestrated by the hormone.

Exogenous testosterone increases status-seeking motivation in men with unstable low social status

Testosterone is associated with status-seeking behaviors such as competition, which may depend on whether one wins or loses status, but also on the stability of one's status. We examined (1) to what extent testosterone administration affects competition behavior in repeated social contests in men with high or low rank, and (2), whether this relationship is moderated by hierarchy stability, as predicted by the status instability hypothesis. Using a real effort-based design in healthy male participants (N = 173 males), we first found that testosterone (vs. placebo) increased motivation to compete for status, but only in individuals with an unstable low status. A second part of the experiment, tailored to directly compare stable with unstable hierarchies, indicated that exogenous testosterone again increased competitive motivation in individuals with a low unstable status, but decreased competition behavior in men with low stable status. Additionally, exogenous testosterone increased motivation in those with a stable high status. Further analysis suggested that these effects were moderated by individuals' trait dominance, and genetic differences assessed by the androgen receptor (CAG-repeat) and dopamine transporter (DAT1) polymorphisms. Our study provides evidence that testosterone specifically boosts status-related motivation when there is an opportunity to improve one's social status. The findings contribute to our understanding of testosterone's causal role in status-seeking motivation in competition behavior, and indicate that testosterone adaptively increases our drive for high status in a context-dependent manner. We discuss potential neurobiological pathways through which testosterone may attain these effects on behavior.

Taking the fight out of people: Exploring how defeat modulates the automatic aggressive response to facial anger

Past studies indicate that angry facial expressions automatically activate an aggressive response, seeming to support the view that humans possess an inborn, automatic tendencies to aggress. However, the current authors drew on influential models from evolutionary game theory to suggest that experiences of defeat may modulate this tendency. To examine this, four experiments were conducted to explore how defeat may modulate this aggressive response. In each study, participants executed simulated fight or flight responses based a computerized opponent's facial expression. Across studies, participants were typically faster to initiate fight (than flight) responses against an angry opponent. Simply losing simulated fights (Experiment 1) or experiencing aversive, white noise following simulated losses (Experiment 2) did not eliminate this tendency. However, when aversive noise was specifically experienced after losing to an angry opponent, the automatic aggressive response was eliminated (Experiment 3). This result was directly replicated (Experiment 4). Thus, these studies isolate the cues which automatize submissive behavior and show that fighting experience can modulate even our automatic aggressive responses to others' anger displays.

Hormonal and emotional responses to competition using a dyadic approach: Basal testosterone predicts emotional state after a defeat

The present study analyzes the testosterone (T), cortisol (C) and emotional response in competitive interactions between dyads, as well as the relationship between basal T and the emotional response. Seventy-two men and women (36 dyads) participated in same-sex dyads in a face-to-face laboratory competition, and thirty-two men and women (16 dyads) carried out the same task in a non-competitive condition. Salivary samples (5 ml of saliva, plastic vials) were provided at three time points (baseline, task, and post-task), and subsequently T (pg/ml) and C (nmol/L) concentrations were measured using ELISA method. Participants completed self-reported measures of emotional valence, emotional arousal and perceived dominance by means of the Self-Assessment Manikin (SAM), at three time points (pre-task, task, and post-task). Two-level crossed Multilevel Models (MLM) showed a participants' stability in C (Mean ± SEM: baseline: 3.84 ± 0.28, task: 2.92 ± 0.28 and post-task: 2.62 ± 0.3), emotional valence (pre-task: 4 ± 0.06, task: 3.66 ± 0.1 and post-task: 3.84 ± 0.09), arousal (pre-task: 3.29 ± 0.09, task: 3.83 ± 0.09 and post-task: 3.38 ± 0.1) and dominance (pre-task: 3.28 ± 0.08, task: 3.4 ± 0.1 and post-task: 3.44 ± 0.09) values, which in the case of emotional valence and dominance was modulated by time-point, outcome and sex. Furthermore, analyses revealed that opponents' C, arousal and dominance values at one time-point influenced participants' values at the following time-point modulated by outcome, sex and time-point. Moreover, MLM indicated that in loser men, individuals higher in basal T (126.31 ± 6.4) displayed higher negative emotional valence after the defeat (post-task: 3.6 ± 0.21), while in women basal T (99.78 ± 12.6) was not significantly related to post competition emotional valence. These findings reinforce the importance of studying the relationship between hormonal and psychological changes in dyadic competition, and confirm that men and women differ in their psychophysiological responses to competition.

Testosterone reduces the threat premium in competitive resource division

Like other animals, humans are sensitive to facial cues of threat. Recent evidence suggests that we use this information to dynamically calibrate competitive decision-making over resources, ceding more to high-threat individuals (who appear more willing/able to retaliate) and keeping more from low-threat individuals. Little is known, however, about the biological factors that support such threat assessment and decision-making systems. In a pre-registered, double-blind, placebo-controlled, cross-over testosterone administration study ( n = 118 men), we show for the first time that testosterone reduces the effects of threat on decision-making: participants ceded more resources to high-threat (versus low-threat) individuals (replicating the 'threat premium'), but this effect was blunted by testosterone, which selectively reduced the amount of resources ceded to those highest in threat. Thus, our findings suggest that testosterone influences competitive decision-making by recalibrating the integration of threat into the decision-making process.

Why and How Should We Integrate Biomarkers into Complex Trials? A Discussion on Paradigms and Clinical Research Strategies

BACKGROUND

Research in complementary and alternative medicine (CAM) encounters a variety of challenges, such as potentially synergistic, multimodal, and complex interventions which are often dependent on the relationship between practitioner and patient, on specific settings, and on patients' individual preferences, expectations, beliefs, and motivations. Moreover, patients seeking CAM care often suffer from chronic disease conditions, and multiple symptoms and/or pathologies. On the other hand, CAM interventions are often challenged as being solely dependent on subjective and nonspecific factors without biologically based mechanisms of action. If we agree that biomarkers as outcomes are important for the understanding of CAM interventions, a hypothesis- and strategy-driven process for the selection of the most appropriate biomarkers is needed.

METHODS

This paper presents the results of an expert panel on how to integrate biomarkers in whole system research of an interdisciplinary workshop on research methodology in CAM held in November 2012.

RESULTS

The following main CAM research challenges were identified: (a) finding appropriate biomarkers, which are able to picture the complex pathophysiological pathways and likewise complex interventions under study; (b) integrating these biomarkers into clinical trials in CAM; and (c) identifying the biomarkers specific to the particular CAM intervention being applied.

CONCLUSION

The paper provides a disease/condition/symptom- and intervention-driven strategy regarding how to identify the outcomes of interest and possible related biomarkers. The research approach presented here allows the selected biomarkers to be grounded in conventional physiology/pathophysiology as well as complementary and alternative concepts, including traditional systems of medicine. The goal is to provide researchers in the field with a framework on how to integrate biomarkers into complex trials.

Putting the flight in "fight-or-flight": Testosterone reactivity to skydiving is modulated by autonomic activation

Sensation-seeking (SS) involves the tendency to pursue exciting activities, potentially including risky behaviors (e.g., substance use, risky sexual behavior). Testosterone is associated with cortisol, SS, and autonomic nervous system (ANS) functioning. Testosterone reactivity/recovery during sky-diving and its relationship to cortisol response, ANS response and SS were examined. Forty-four participants provided reactive saliva samples and autonomic activity data before, during and after sky-diving and as well as basal day saliva samples. Testosterone reactivity/recovery to skydiving was significantly greater than basal day measurements. Testosterone responsivity to skydiving was predicted by increased cortisol, increased sympathetic activity (heart rate) and reduced parasympathetic activity (RMSSD). Independent of physiological effects, increased SS predicted testosterone responsivity to skydiving. These data suggest that testosterone reactivity, and its relationship to ANS responsivity, may be associated with pleasurable responses to risky/intense situations. These data may be useful in developing novel intervention strategies for risky behaviors.

Sleep restriction alters reactive aggressive behavior and its relationship with sex hormones

Few studies have experimentally manipulated sleep to study its effect on aggressive behavior. The current study examined how reactive aggression was affected by having sleep restricted to 4-hours on a single night, a level of disruption commonly experienced. Both rested and sleep-restricted participants completed the Point Subtraction Aggression Paradigm (PSAP), a laboratory task in which participants seek to earn points, are provoked by a fictitious opponent stealing their points, and may choose to steal points in response. Logistic mixed-effect models were used to investigate the effect of sleep restriction and the role of sex hormones on the odds of choosing to steal. For men, and women in the luteal phase of the menstrual cycle, sleep restriction did not result in significant changes reactive aggression, although the patterns of aggressive behavior appeared less reactive and retaliatory in nature. For women in the follicular phase of the menstrual cycle, sleep restriction was associated with higher levels of reactive aggression. For both men and women in the luteal phase, sleep restriction disrupted an association between hormone change over the task (testosterone and estradiol, respectively) and reactive aggression that was observed in their control participants. In addition, higher testosterone before the PSAP in men was associated with maintaining a high level of stealing over the task. These results indicate a complex dynamic in which sex hormones and sleep interact to predict aggressive behavior in response to provocation.

Sex differences in testosterone reactivity during marital conflict

When attempting to resolve relationship problems, individuals in close relationships sometimes challenge their partners with statements that oppose their partners' point of view. Such oppositional behaviors may undermine those partners' relational value and threaten their status within the relationship. We examined whether perceptions of opposition from a partner during a series of problem-solving interactions were associated with reactivity in testosterone levels and whether those associations were different for men and women. Fifty newlywed couples discussed four marital problems. Each member of the couple reported how much oppositional behavior they perceived from their partner during the discussions. Pre- and post-discussion saliva samples were assayed for testosterone. For men, but not for women, perceptions of oppositional behavior were associated with heightened testosterone reactivity, and this result replicated across three different measures of testosterone reactivity. Findings were specific to men's perceptions of oppositional behavior, and held controlling for objective measures of oppositional behavior coded from videos of the conversations. Results highlight the benefits of considering pair-bonded relationships as a novel context for investigating associations involving hormones and behavior. Findings also raise the possibility that sex differentiated hormonal reactions to opposition partly explain why conflict among heterosexual partners can be so divisive.

Human social neuroendocrinology: Review of the rapid effects of testosterone

Contribution to Special Issue on Fast effects of steroids. It is well documented that testosterone concentrations change rapidly within reproductively relevant contexts (e.g., competition, mate-seeking). It has been argued that such rapid changes in testosterone may serve to adaptively fine-tune ongoing and/or future social behaviour according to one's social environment. In this paper, we review human correlational and experimental evidence suggesting that testosterone fluctuates rapidly in response to competition and mate-seeking cues, and that such acute changes may serve to modulate ongoing and/or future social behaviours (e.g., risk-taking, competitiveness, mate-seeking, and aggression). Some methodological details, which limit interpretation of some of this human work, are also discussed. We conclude with a new integrative model of testosterone secretion and behaviour, the Fitness Model of Testosterone Dynamics. Although we focus primarily on human aggression in this review, we also highlight research on risk-taking, competitiveness, and mate-seeking behaviour.

Testosterone and Cortisol Responses to Five High-Intensity Functional Training Competition Workouts in Recreationally Active Adults

To determine the salivary steroid response to high-intensity functional training (HIFT) competition workouts, saliva samples were collected from ten recreationally trained male and female competitors during a 5-week (WK1–WK5) international competition. Competitors arrived at their local affiliate and provided samples prior to (PRE) their warm-up, immediately (IP), 30-min (30P), and 60-min (60P) post-exercise. Samples were analyzed for concentrations of testosterone (T), cortisol (C), and their ratio (TC). Generalized linear mixed models with repeated measures revealed significant main effects for time (p < 0.001) for T, C, and TC. Compared to PRE-concentrations, elevated (p < 0.05) T was observed at IP on WK2–WK5 (mean difference: 135–511 pg·mL⁻¹), at 30P on WK3 (mean difference: 81.0 ± 30.1 pg·mL⁻¹) and WK5 (mean difference: 56.6 ± 22.7 pg·mL⁻¹), and at 60P on WK3 (mean difference: 73.5 ± 29.7 pg·mL⁻¹) and WK5 (mean difference: 74.3 ± 28.4 pg·mL⁻¹). Compared to PRE-concentrations, elevated (p < 0.05) C was noted on all weeks at IP (mean difference: 9.3–15.9 ng·mL⁻¹) and 30P (mean difference: 6.0–19.9 ng·mL⁻¹); significant (p < 0.006) elevations were noted at 60P on WK1 (mean difference: 9.1 ± 3.0 ng·mL⁻¹) and WK5 (mean difference: 12.8 ± 2.9 ng·mL⁻¹). Additionally, TC was significantly reduced from PRE-values by 61% on WK1 at 60P (p = 0.040) and by 80% on WK5 at 30P (p = 0.023). Differences in T, C, and TC were also observed between weeks at specific time points. Although each workout affected concentrations in T, C, and/or the TC ratio, changes appeared to be modulated by the presence of overload and workout duration. During periods of elevated training or competition, athletes and coaches may consider monitoring these hormones for consistency and as a means of assessing workout difficulty.

When anger expression might be beneficial for African Americans: The moderating role of chronic discrimination

OBJECTIVES

Anger expression is assumed to have mostly negative health effects. Yet, evidence is mixed on how anger expression influences African Americans' cardiovascular health. The present research aimed to clarify this link by examining moderating effects of chronic discrimination on the relationship between anger expression and cardiovascular risk among African Americans in experimental (Study 1) and epidemiological (Study 2) studies.

METHOD

Study 1 examined how African Americans' trait anger expression was linked to (a) physiologic reactivity to acute social rejection during an interracial encounter (Session 1); and (b) total/HDL cholesterol assessed two months later (Session 2). Study 2 examined the relationship between anger expression and total/HDL cholesterol with a larger sample of African Americans from the Midlife in the United States (MIDUS) survey. Both studies examined perceptions of chronic discrimination as a moderator of the relationships between anger expression and biological responses.

RESULTS

In Study 1 higher anger expression was associated with quicker cortisol recovery and greater testosterone reactivity following outgroup social rejection in Session 1 and lower total/HDL cholesterol in Session 2. Study 2 replicated the relationship between anger expression and lower total/HDL cholesterol and further showed that this relationship was unique to the expressive aspect of anger. Importantly, in both studies, these potentially beneficial effects of anger expression were only evident among individuals with lower perceptions of chronic discrimination.

CONCLUSIONS

These findings suggest that anger expression, when coupled with low levels of chronic discrimination, is associated with adaptive patterns of physiologic responses among African Americans. (PsycINFO Database Record

Reactive aggression tracks within-participant changes in women's salivary testosterone

The relation between testosterone and aggression has been relatively well documented in men, but it is less well understood in women. Here we assessed the relationship between salivary testosterone and reactive aggression (i.e., rejection rate for unfair offers) in the Ultimatum Game. Forty naturally cycling women were tested twice, once in the late follicular phase (around ovulation) and once during the luteal phase. Ovulation was determined using urine test strips measuring luteinizing hormone levels. Salivary samples were assayed for testosterone, estradiol, progesterone, and cortisol at both test sessions. There was no association with the cycle, but multilevel modeling revealed a significant within-participant association between testosterone and rejection rate for extremely unfair offers (i.e., high reactive aggression), indicating that women showed greater reactive aggression when their testosterone levels were higher. Additionally, we found that women with relatively high individual concentrations of testosterone were more likely to reject extremely unfair offers than women with relatively low concentrations of testosterone. This study is the first to demonstrate that women react more aggressively in response to provocation when their testosterone level is high than when their testosterone is low, suggesting that testosterone plays an important role in the regulation of women's aggressive behavior following social provocation.

The salivary testosterone response to a chance-determined contest is associated with face-gazing behaviours in athletic women

Human gaze is an important indicator of dominant and submissive behaviours related to positioning in a social hierarchy. This study investigated face gazing after a chance-determined contest and its linkage to salivary testosterone (sal-T) reactivity in athletic women. Twenty-six women athletes completed a coin-toss game on days 7 (D7), 14 (D14) and 21 (D21) of a single menstrual cycle. The game was played against an unknown opponent of similar age with the winner congratulated and rewarded with all coins. Gazing towards an opponent's head or face was timed after each contest (over 2 min) from video footage. Salivary T (sal-T) was assessed before and 15 min after these contests. The sal-T residuals increased after winning and decreased after losing on D7, D14 and D21 (p < 0.05). Gaze times were longer after a loss (M = 7.8 s) than a win (M = 3.1 s) across all days. Regression analyses revealed that the sal-T residuals and contest outcome interacted to predict gaze time. Upon deconstruction we found that, when losing a contest, a larger sal-T response (i.e., smaller decline) predicted a longer gaze (β = 1.71, p = 0.004), but no association was evident when winning (β = -0.06, p = 0.821), and these slope patterns differed (p = 0.011). In conclusion, winning a contest by chance increased sal-T responsivity and decreased opponent gaze across the menstrual cycle. A positive relationship between individual sal-T reactivity and gaze duration was observed, but only when losing. These preliminary results support suggestions that women's T may help modulate post-competition behaviours (e.g., face gazing) possibly to achieve social cohesion and cooperation.

How Social Status Shapes Person Perception and Evaluation: A Social Neuroscience Perspective

Inferring the relative rank (i.e., status) of others is essential to navigating social hierarchies. A survey of the expanding social psychological and neuroscience literatures on status reveals a diversity of focuses (e.g., perceiver vs. agent), operationalizations (e.g., status as dominance vs. wealth), and methodologies (e.g., behavioral, neuroscientific). Accommodating this burgeoning literature on status in person perception, the present review offers a novel social neuroscientific framework that integrates existing work with theoretical clarity. This framework distinguishes between five key concepts: (1) strategic pathways to status acquisition for agents, (2) status antecedents (i.e., perceptual and knowledge-based cues that confer status rank), (3) status dimensions (i.e., domains in which an individual may be ranked, such as wealth), (4) status level (i.e., one's rank along a given dimension), and (5) the relative importance of a given status dimension, dependent on perceiver and context characteristics. Against the backdrop of this framework, we review multiple dimensions of status in the nonhuman and human primate literatures. We then review the behavioral and neuroscientific literatures on the consequences of perceived status for attention and evaluation. Finally, after proposing a social neuroscience framework, we highlight innovative directions for future social status research in social psychology and neuroscience.

Thin Slices of Athletes' Nonverbal Behavior Give Away Game Location: Testing the Territoriality Hypothesis of the Home Game Advantage

The present research investigated whether perceivers could detect who is playing at home or away in soccer matches based on thin slices of professional (Experiment 1) and amateur (Experiment 3) athletes' nonverbal behavior prior to the match and whether perceivers rated athletes playing at home relatively higher on behavioral dimensions (Experiments 2 and 3) linked to territoriality. In Experiment 1 ( N = 80), participants watched short videos depicting soccer players prior to a UEFA Champions League match and rated whether athletes were more likely to be playing at home or away. In Experiment 2 (two groups N = 102 and N = 101), perceivers rated these videos in terms of assertiveness, dominance, and aggression. In Experiment 3, we replicated the procedure of Experiments 1 and 2 with different stimulus material from amateur soccer ( N = 112). Participants could significantly differentiate between home playing and away playing athletes (Experiment 1: d = 0.44 and Experiment 3: d = 1.07). Experiments 2 and 3 showed that perceivers rated professional and amateur soccer players higher on assertiveness ( d = 0.34-0.63), dominance ( d = 0.20-0.55), and aggression ( d = 0.16-0.49) when playing at home compared to playing away. Findings are supportive of evolutionary accounts of nonverbal behavior, ecological approaches to person perception, and the thin slices of behavior hypothesis by demonstrating that humans change their nonverbal behavior depending on game location. We discuss the relevance of the present findings for the home advantage in sports.

Exogenous Testosterone Enhances the Reactivity to Social Provocation in Males

Testosterone affects human social behavior in various ways. While testosterone effects are generally associated with muscular strength and aggressiveness, human studies also point towards enhanced status–seeking motives after testosterone administration. The current study tested the causal influence of exogenous testosterone on male behavior during a competitive provocation paradigm. In this double blind, randomized, placebo (PL)-controlled study, 103 males were assigned to a PL or testosterone group receiving a colorless PL or testosterone gel. To induce provocation, males played a rigged reaction time game against an ostensible opponent. When participants lost, the opponent subtracted money from the participant who in return could subtract money from the ostensible opponent. Participants subjectively indicated anger and self-estimated treatment affiliation (testosterone or PL administration). A trial-by-trial analysis demonstrated that provocation and success during the repeated games had a stronger influence on participants’ choice to reduce money from the opponent if they had received testosterone. Participants who believed to be in the testosterone group were angrier after the experiment and increased monetary reductions during the task course. In line with theories about mechanisms of testosterone in humans, provocation is shown to be necessary for the agency of exogenous testosterone. Thus, testosterone reinforces the conditional adjustment of aggressive behavior but not aggressive behavior per se. In contrast undirected frustration is not increased by testosterone but probably interferes with cognitive appraisals about biological mechanisms of testosterone.

Implicit and Explicit Motivational Tendencies to Faces Varying in Trustworthiness and Dominance in Men

Motivational tendencies to happy and angry faces are well-established, e.g., in the form of aggression. Approach-avoidance reactions are not only elicited by emotional expressions, but also linked to the evaluation of stable, social characteristics of faces. Grounded in the two fundamental dimensions of face-based evaluations proposed by Oosterhof and Todorov (2008), the current study tested whether emotionally neutral faces varying in trustworthiness and dominance potentiate approach-avoidance in 50 healthy male participants. Given that evaluations of social traits are influenced by testosterone, we further tested for associations of approach-avoidance tendencies with endogenous and prenatal indicators of testosterone. Computer-generated faces signaling high and low trustworthiness and dominance were used to elicit motivational reactions in three approach-avoidance tasks, i.e., one implicit and one explicit joystick-based paradigm, and an additional rating task. When participants rated their behavioral tendencies, highly trustworthy faces evoked approach, and highly dominant faces evoked avoidance. This pattern, however, did not translate to faster initiation times of corresponding approach-avoidance movements. Instead, the joystick tasks revealed general effects, such as faster reactions to faces signaling high trustworthiness or high dominance. These findings partially support the framework of Oosterhof and Todorov (2008) in guiding approach-avoidance decisions, but not behavioral tendencies. Contrary to our expectations, neither endogenous nor prenatal indicators of testosterone were associated with motivational tendencies. Future studies should investigate the contexts in which testosterone influences social motivation.

External motivation to avoid prejudice alters neural responses to targets varying in race and status

Those who are high in external motivation to respond without prejudice (EMS) tend to focus on non-racial attributes when describing others. This fMRI study examined the neural processing of race and an alternative yet stereotypically relevant attribute (viz., socioeconomic status: SES) as a function of the perceiver's EMS. Sixty-one White participants privately formed impressions of Black and White faces ascribed with high or low SES. Analyses focused on regions supporting race- and status-based reward/salience (NAcc), evaluation (VMPFC) and threat/relevance (amygdala). Consistent with previous findings from the literature on status-based evaluation, we observed greater neural responses to high-status (vs low-status) targets in all regions of interest when participants were relatively low in EMS. In contrast, we observed the opposite pattern when participants were relatively high in EMS. Notably, all effects were independent of target race. In summary, White perceivers' race-related motivations similarly altered their neural responses to the SES of Black and White targets. Specifically, the findings suggest that EMS may attenuate the positive value and/or salience of high status in a mixed-race context. Findings are discussed in the context of the stereotypic relationship between race and SES.