Trait Anxiety Moderates the Relationship Between Testosterone Responses to Competition and Aggressive Behavior

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.

Narcissism moderates the association between basal testosterone and generosity in men

Research has linked hormones to behavioral outcomes in intricate ways, often moderated by psychological dispositions. The associations between testosterone and antisocial or prosocial outcomes also depend on dispositions relevant to status and dominance. In two studies (N1 = 68, N2 = 83), we investigated whether endogenous testosterone, measured in saliva, and narcissism, a psychological variable highly relevant to status motivation, interactively predicted men's preferences regarding resource allocation. Narcissism moderated the links between testosterone and social value orientation: among low narcissists testosterone negatively predicted generosity in resource allocation and probability of endorsing a prosocial (vs. pro-self) value orientation, whereas among high narcissists testosterone tended to positively predict generosity and the probability of endorsing a prosocial (vs. pro-self) value orientation. We discuss these results as examples of calibrating effects of testosterone on human behavior, serving to increase and maintain social status. We advocate the relevance of psychological dispositions, alongside situations, when examining the role of T in social outcomes.

Testosterone and cortisol variation due to training and fight in Judokas

BACKGROUND

The aim of this study was to evaluate the effectiveness of judo workout by determining the testosterone (T) and cortisol (C) responses and their associations with the results of a judo fight.

METHODS

A prospective study involved 17 judokas. Three blood samples were taken from each athlete: at rest, immediately after a 90 min training session and 72 hours later immediately after a 5 min fight , to evaluate T, C and lactic acid.

RESULTS

Results showed no significant difference for T (p = 0.17), C (p = 0.51) or testosterone/cortisol (T/C) ratio (t = 0.901 (16), p =0.38) after training. A significant difference was found for the C (p =0.002) and the T/C ratio (p =0.04) after the fight. In contrast with the losers, the winner judokas reported a significant increase in the C (p = 0.002) and T (p = 0.013) concentrations at rest and after the fight. No significant difference was found for C (p = 0.77) or T (p = 0.43) at rest and after training.

CONCLUSIONS

The "fight" effort induced more biological stress than the "training" effort. In addition, the cortisol response and the T/C ratio revealed an association with a subsequent victorious judo fight. Thus, the hormonal response, particularly the C concentration, to a training could allow the assessment of the readiness of judokas for a future competition. This new strategy can allow to better manage the capacity of judoka at the training for the sake of an improvement of performance during competitions.

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.

DOES PRE-COMPETITIVE ANXIETY INTERFERE IN THE PERFORMANCE OF BOXING ATHLETES IN BRAZIL? A PILOT STUDY

ABSTRACT Introduction: Pre-competitive anxiety is one of the psychological factors that can greatly influence athletes' performance, especially when it comes to individual sport like boxing. Objective: To analyze the level of pre-competitive anxiety in male athletes in the adult and young adult categories, and their correlation with the final results of the last Brazilian National Championship. Methods: A total of 60 young adult athletes participated in the study: 38 non-medalists (17.17±0.54 years and 66.38±13.21 kg) and 22 medalists (17.48±0.54 years and 66.21±12.96 kg). The “adults” group consisted of 35 athletes: 11 non-medalists (22.60±4.65 years and 68.33±14.08 kg) and 24 medalists (22.60±4.82 years and 67.33 ±13.13 kg). Results: The levels of cognitive anxiety in the young adult athletes group presented significant differences: medalists presented lower scores than non-medalists (12.77±2.62 and 15.92±5.20, respectively). In the adults group, medalists presented higher scores than non-medalists (15.23±4.42 and 12.00±4.11). Significant differences were observed in somatic anxiety levels between the young adult medalists and the other groups (p = 0.038). In addition, levels of self-confidence were high in all groups (young adult non-medalists = 29.42±4.82; adult non-medalists = 26.14±4.94, young adult medalists = 31.59±4.24 and adult medalists = 28.91±4.88). Conclusion: We conclude that self-confidence may interfere with anxiety levels, considering that medal-winning boxers are less prone to cognitive anxiety than non-medalists, and that both groups have high levels of self-confidence. Level of evidence I; High quality randomized trial with statistically significant difference or no statistically significant difference but narrow confidence intervals.

Referee height influences decision making in British football leagues

BACKGROUND

Male height is positively associated with social dominance, and more agonistic/competitive behaviours. However, the 'Napoleon complex' or 'small man syndrome' suggests that smaller males are more assertive and punitive to compensate for lack of height and social dominance. Here, we assess possible relationships between height and punitive behaviours in a real-world setting.

METHODS

Using a non-experimental correlational design, we analysed data on 61 male association football referees from four professional leagues in England, and explored relationships between their height and punitive behaviours in the form of yellow cards, red cards and penalties given during an entire season.

RESULTS

Overall there was no effect of referee height on fouls awarded. However, there was a main effect of height on yellow cards awarded, with shorter referees issuing more yellow cards. The same effect was found for red cards and penalties, though this was moderated by league. In the lower leagues, more red cards and penalties were awarded by relatively shorter referees, but in the higher leagues more red cards and penalties were awarded by relatively taller referees.

CONCLUSIONS

These findings from real-life public dominance encounters show that height is associated with punitive behaviours, but is sensitive to context.

Unstable correspondence between salivary testosterone measured with enzyme immunoassays and tandem mass spectrometry

Although some studies reveal that saliva handling and storage practices may influence salivary testosterone concentrations measured with immunoassays, the effect of these method factors on the validity of testosterone immunoassays remains unknown. The validity of immunoassays can be assessed by comparing hormone concentrations measured with immunoassays to a standard reference method: liquid chromatography tandem mass spectrometry (MS). We previously reported the correspondence between salivary testosterone measured with enzyme immunoassays (EIAs) and with MS when there was less variance in (or more control over) method factors related to saliva handling and storage across measurement methods (Welker et al., 2016). In the present study, we expanded the original dataset and compared the correspondence between Salimetrics EIAs and MS when there was greater variance in (or less control over) method factors across EIAs and MS (high method variance), to when there was less variance in these factors (low method variance). If variance in these method factors impacts the validity of testosterone measurement, then the EIA-MS correspondence should be stronger when method variance is low compared to when it is high. Our results contradicted this hypothesis: Salimetrics EIA-MS correspondence was stronger when variance in method factors was high compared to when it was low. The composite average correlation across both method variance comparisons provides an updated estimate of Salimetrics EIA-MS correspondence, but the instability in this correspondence may pose challenges to the reproducibility of psychoneuroendocrinology research. We discuss possible explanations for the surprising pattern of results and provide recommendations for future research.

Fathers: The interplay between testosterone levels and self-control in relation to parenting quality

In this study, we examined the potential interaction effect between fathers' basal testosterone levels and their ability to control their impulses in relation to their quality of parenting. Participants included 159 fathers and their preschoolers. Evening and morning salivary samples were analyzed with isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) to determine basal testosterone (T) levels. During a home-visit, fathers' self-control was measured with a computerized Go/NoGo task, and their sensitivity and respect for child autonomy was observed in a free-play session. We found that higher T levels in the evening were related to less respect for child autonomy, but only in fathers with low self-control. Further, higher T in the evening was related to more sensitive parenting, yet only in fathers with high self-control. These findings indicate that different aspects of fathers' quality of parenting are differently affected by the interaction between T and self-control. Further research is needed to clarify the interplay between fathers' neuro-endocrine system functioning and their trait characteristics in relation to the development of father-child relationships.

Aggression Toward Sexualized Women Is Mediated by Decreased Perceptions of Humanness

Researchers have argued that the regulation of female sexuality is a major catalyst for women's intrasexual aggression. The present research examined whether women behave more aggressively toward a sexualized woman and whether this is explained by lower ratings of the target's humanness. Results showed that women rated another woman lower on uniquely human personality traits when she was dressed in a sexualized (vs. conventional) manner. Lower humanness ratings subsequently predicted increased aggression toward her in a behavioral measure of aggression. This effect was moderated by trait intrasexual competitiveness; lower humanness ratings translated into more aggression, but only for women scoring relatively high on intrasexual competition. Follow-up studies revealed that the effect of sexualized appearance on perceived humanness was not due to the atypicality of the clothing in a university setting. The current project reveals a novel psychological mechanism through which interacting with a sexualized woman promotes aggressive behavior toward her.

Aggression-related brain function assessed with the Point Subtraction Aggression Paradigm in fMRI

The Point Subtraction Aggression Paradigm (PSAP) measures aggressive behavior in response to provocations. The aim of the study was to implement the PSAP in a functional neuroimaging environment (fMRI) and evaluate aggression-related brain reactivity including response to provocations and associations with aggression within the paradigm. Twenty healthy participants completed two 12-min PSAP sessions within the scanner. We evaluated brain responses to aggressive behavior (removing points from an opponent), provocations (point subtractions by the opponent), and winning points. Our results showed significant ventral and dorsal striatal reactivity when participants won a point and removed one from the opponent. Provocations significantly activated the amygdala, dorsal striatum, insula, and prefrontal areas. Task-related aggressive behavior was positively correlated with neural reactivity to provocations in the insula, the dorsal striatum, and prefrontal areas. Our findings suggest the PSAP within an fMRI environment may be a useful tool for probing aggression-related neural pathways. Activity in the amygdala, dorsal striatum, insula, and prefrontal areas during provocations is consistent with the involvement of these brain regions in emotional and impulsive behavior. Striatal reactivity may suggest an involvement of reward during winning and stealing points.

Preliminary evidence that acute stress moderates basal testosterone's association with retaliatory behavior

A contribution to a special issue on Hormones and Human Competition. Testosterone is theorized to increase retaliation after social provocation. However, empirical evidence in support of these theories is mixed. The present research investigated whether acute stress causally suppresses testosterone's association with retaliation. We also explored sex differences in behavioral responses to acute stress. Thirty-nine participants (51.28% male) were randomly assigned to a high- or low-stress condition. Then participants engaged in 20 one-shot rounds of the ultimatum game, which was used to assess retaliatory behavioral responses to unfair treatment. Participants provided two saliva samples to measure testosterone and cortisol concentrations - one sample before the stress manipulation, and the second after the ultimatum game (20minutes post-stressor). Results revealed a positive association between basal testosterone and retaliation in the low-stress condition, but not in the high-stress condition. Further, cortisol concentrations increased in the high- compared to the low-stress condition, and these cortisol changes moderated the association between basal testosterone and retaliation. The associations between basal testosterone and retaliation under varying levels of stress were similar in men and women. However, there was a sex difference in behavioral responses to the stress manipulation that was independent of testosterone. In women, the high-stress condition reduced retaliation compared to the low-stress condition, whereas in men the opposite pattern emerged. Collectively, this study (i) provides preliminary evidence that experimentally manipulated stress blocks basal testosterone's association with retaliation, and (ii) reveals a sex difference in retaliation under varying levels of stress. Discussion focuses on mechanisms, limitations, and the need for follow-up studies with larger sample sizes.

The Point Subtraction Aggression Paradigm as a laboratory tool for investigating the neuroendocrinology of aggression and competition

A contribution to a special issue on Hormones and Human Competition.The ease of measuring steroids in saliva has led to an increase in investigating their role in competition and aggression in laboratory settings and using behavioral measures of aggression. We review here the Point-Subtraction-Aggression-Paradigm (PSAP) as a measure of costly aggression and we compare and contrast the PSAP to other aggression measures. We describe our use of the PSAP, highlighting how it can be modified to investigate a broad array of experimental questions. We review studies that have investigated neuroendocrine function and the PSAP, and we conclude that across studies the relationship between fluctuations in testosterone and PSAP aggression scores are directionally positive, and are likely specific to men. Investigations of other neuroendocrine measures and the PSAP are fewer, limiting conclusions that can be drawn for other hormones. We provide two versions of the PSAP that can be used with E-PRIME® software for researchers interested in this measure for their laboratories.

Effects of competition outcome on testosterone concentrations in humans: An updated meta-analysis

A contribution to a special issue on Hormones and Human Competition. Since Archer's (2006) influential meta-analysis, there has been a major increase in the number of studies investigating the effect of competition outcome on testosterone reactivity patterns in humans. Despite this increased research output, there remains debate as to whether competition outcome modulates testosterone concentrations. The present paper examines this question using a meta-analytic approach including papers published over the last 35years. Moreover, it provides the first meta-analytic estimate of the effect of competition outcome on testosterone concentrations in women. Results from a meta-analysis involving 60 effect sizes and >2500 participants indicated that winners of a competition demonstrated a larger increase in testosterone concentrations relative to losers (D=0.20)-an effect that was highly heterogeneous. This 'winner-loser' effect was most robust in studies conducted outside the lab (e.g., in sport venues) (D=0.43); for studies conducted in the lab, the effect of competition outcome on testosterone reactivity patterns was relatively weak (D=0.08), and only found in studies of men (D=0.15; in women: D=-0.04). Further, the 'winner-loser' effect was stronger among studies in which pre-competition testosterone was sampled earlier than (D=0.38, after trim and fill correction) rather than within (D=0.09) 10min of the start of the competition. Therefore, these results also provide important insight regarding study design and methodology, and will be a valuable resource for researchers conducting subsequent studies on the 'winner loser' effect.

The effects of competition and implicit power motive on men's testosterone, emotion recognition, and aggression

A contribution to a special issue on Hormones and Human Competition. We investigated the effects of competition on men's testosterone levels and assessed whether androgen reactivity was associated with subsequent emotion recognition and reactive and proactive aggression. We also explored whether personalized power (p Power) moderated these relationships. In Study 1, 84 males competed on a number tracing task and interpreted emotions from facial expressions. In Study 2, 72 males competed on the same task and were assessed on proactive and reactive aggression. In both studies, contrary to the biosocial model of status (Mazur, 1985), winners' testosterone levels decreased significantly while losers' levels increased, albeit not significantly. Personalized power moderated the effect of competition outcome on testosterone change in both studies. Using the aggregate sample, we found that the effect of decreased testosterone levels among winners (compared to losers) was significant for individuals low in p Power but not for those with medium or high p Power. Testosterone change was positively related to emotion recognition, but unrelated to either aggression subtype. The testosterone-mediated relationship between winning and losing and emotion recognition was moderated by p Power. In addition, p Power moderated the direct (i.e., non-testosterone mediated) path between competition outcome and emotion recognition and both types of aggression: high p-Power winners were more accurate at deciphering others' emotions than high p-Power losers. Finally, among high p-Power men, winners aggressed more proactively than losers, whereas losers aggressed more reactively than winners. Collectively, these studies highlight the importance of implicit power motivation in modulating hormonal, cognitive, and behavioral outcomes arising from human competition.

The roles of testosterone and cortisol in friendship formation

Although research has investigated the neuroendocrine correlates of romantic relationships, the neuroendocrine correlates of friendship formation are largely unexplored. In two conditions, participants' salivary testosterone and cortisol were measured before and after a high versus low closeness activity with another same-sex participant. In the high closeness task, participants took turns answering questions that fostered increases in self-disclosure. The low closeness task fostered low levels of self-disclosure. Dyadic multilevel models indicated that lower basal testosterone and decreases in testosterone were associated with increased closeness between recently acquainted strangers. Our results suggest that people high in testosterone felt less close to others and desired less closeness. Further, lower basal cortisol and dynamic cortisol decreases were associated with greater closeness and desired closeness in the high closeness condition. Finally, we found that the partners of those who had lower cortisol desired more closeness. These findings suggest that lower testosterone and cortisol are linked to the facilitation of initial social bonds and that these social bonds may, in turn, be associated with changes in these hormones.

Threatening Men's Mate Value Influences Aggression Toward an Intrasexual Rival: The Moderating Role of Narcissism

Correlational research has linked low mate value (MV)--one's worth as a mating partner to members of the opposite sex--with aggression in men. In 2 experiments, we examined the effects of self-perceived MV on men's reported willingness to aggress directly toward a hypothetical mate poacher (Experiment 1, N = 60) and observable aggression toward a same-sex rival in a laboratory paradigm (Experiment 2, N = 54). In both experiments, the roles of narcissism in moderating the effect of MV condition on subsequent aggression were examined. Results of Experiment 1 indicated that men randomly assigned to the low MV condition were significantly more willing to report aggressive intention than men in the high MV condition. This relationship was moderated by narcissism such that men in the low MV condition who were also high in narcissism were the most likely to aggress. Results of Experiment 2 similarly showed that men in the low MV condition relative to the high MV condition aggressed more toward a same-sex rival when they were high in narcissism. These findings support evolutionary hypotheses surrounding the importance of self-perceived MV in directing aggressive mating efforts, as situated in the framework of threatened egotism.

Testosterone, cortisol, and human competition

Testosterone and cortisol figure prominently in the research literature having to do with human competition. In this review, we track the history of this literature, concentrating particularly on major theoretical and empirical contributions, and provide commentary on what we see as important unresolved issues. In men and women, athletic competition is typically associated with an increase in testosterone (T) and cortisol (C). Hormone changes in response to non-athletic competition are less predictable. Person (e.g., power motivation, mood, aggressiveness, social anxiety, sex, and baseline levels of T and C) and context (e.g., whether a competition is won or lost, the closeness of the competition, whether the outcome is perceived as being influenced by ability vs. chance, provocations) factors can influence hormone responses to competition. From early on, studies pointed to a positive relationship between T and dominance motivation/status striving. Recent research, however, suggests that this relationship only holds for individuals with low levels of C - this is the core idea of the dual-hormone hypothesis, and it is certain that the broadest applications of the hypothesis have not yet been realized. Individuals differ with respect to the extent to which they embrace competition, but the hormonal correlates of competitiveness remain largely unexplored. Although rapid increases in both T and C associated with competition are likely adaptive, we still know very little about the psychological benefits of these hormonal changes. Administration studies have and will continue to contribute to this inquiry. We close with a discussion of what, we think, are important methodological and mechanistic issues for future research.

Social neuroendocrinology of human aggression: examining the role of competition-induced testosterone dynamics

A large body of evidence indicates that individual differences in baseline concentrations of testosterone (T) are only weakly correlated with human aggression. Importantly, T concentrations are not static, but rather fluctuate rapidly in the context of competitive interactions, suggesting that acute fluctuations in T may be more relevant for our understanding of the neuroendocrine mechanisms underlying variability in human aggression. In this paper, we provide an overview of the literature on T and human competition, with a primary focus on the role of competition-induced T dynamics in the modulation of human aggression. In addition, we discuss potential neural mechanisms underlying the effect of T dynamics on human aggression. Finally, we highlight several challenges for the field of social neuroendocrinology and discuss areas of research that may enhance our understanding of the complex bi-directional relationship between T and human social behavior.