Testosterone's role in modulating human behaviors relevant to mating and parenting.

Testosterone (T) is linked to human mating and parenting. Here, we comprehensively reviewed evidence on whether, in men and women, (1) basal T levels are related to mating and parenting behaviors, (2) T responds to reproduction-relevant cues, (3) acute changes in T map onto subsequent mating and parenting behaviors, and (4) single-dose exogenous T administration causally affects mating and parenting behaviors. We examined whether the available evidence supports trade-off interpretations of T's adaptive function whereby high T levels correspond to greater mating/reproductive effort and competition and low T levels to greater parenting effort and nurturance. We found mixed support for trade-off hypotheses, suggesting that T's function in modulating human mating and parenting might be more nuanced and highly dependent on context and individual trait differences. Results were largely similar for men and women, although studies with women were scarcer than those with men for most behaviors we reviewed.

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.

Fetal Hippocampal Connectivity Shows Dissociable Associations with Maternal Cortisol and Self-Reported Distress during Pregnancy.

Maternal stress can shape long-term child neurodevelopment beginning in utero. One mechanism by which stress is transmitted from mothers to their offspring is via alterations in maternal cortisol, which can cross the placenta and bind to glucocorticoid receptor-rich regions in the fetal brain, such as the hippocampus. Although prior studies have demonstrated associations between maternal prenatal stress and cortisol levels with child brain development, we lack information about the extent to which these associations originate prior to birth and prior to confounding postnatal influences. Pregnant mothers (n = 77) completed questionnaires about current perceived stress, depressive symptoms, and anxiety symptoms, provided three to four salivary cortisol samples, and completed a fetal resting-state functional MRI scan during their second or third trimester of pregnancy (mean gestational age = 32.8 weeks). Voxelwise seed-based connectivity analyses revealed that higher prenatal self-reported distress and higher maternal cortisol levels corresponded to dissociable differences in fetal hippocampal functional connectivity. Specifically, self-reported distress was correlated with increased positive functional coupling between the hippocampus and right posterior parietal association cortex, while higher maternal cortisol was associated with stronger positive hippocampal coupling with the dorsal anterior cingulate cortex and left medial prefrontal cortex. Moreover, the association between maternal distress, but not maternal cortisol, on fetal hippocampal connectivity was moderated by fetal sex. These results suggest that prenatal stress and peripheral cortisol levels may shape fetal hippocampal development through unique mechanisms.

Relatively rapid effects of testosterone on men's ratings of female attractiveness depend on relationship status and the attractiveness of stimulus faces.

Attractiveness judgements influence desires to initiate and maintain romantic relationships. Testosterone also predicts relationship initiation and maintenance; such effects may be driven by the hormone's modulation of attractiveness judgements, but no studies have investigated causal (and situation-dependent) effects of the hormone on these judgements. Using a placebo-controlled cross-over design, our preregistered analyses revealed order- and relationship- dependent effects: single heterosexual men judged the women as more appealing when testosterone was administered first (and placebo second), but marginally less appealing when placebo was administered first (and testosterone second). In a more complex model incorporating the women's attractiveness (as rated by an independent set of observers), however, we show that testosterone increases the appeal of women -but this effect depends upon the men's relationship status and the women's attractiveness. In partnered men (n = 53) who tend to derogate attractive alternatives (by rating them as less appealing), testosterone countered this effect, boosting the appeal of these attractive alternatives. In single men (n = 53), conversely, testosterone increased the appeal of low-attractive women. These differential effects highlight the possibility of a newly discovered mechanism whereby testosterone promotes male sexual reproduction through different routes depending on relationship status, promoting partner up- rather than down-grading when partnered and reducing choosiness when single. Further, such effects were relatively rapid [within 85 (±5) minutes], suggesting a potential non-genomic mechanism of action.

"Beyond the Rink": A Multilevel Analysis of Social Identity Behaviors Captured Using the Electronically Activated Recorder.

This study used ecological sampling methods to examine associations between youth athletes' experiences receiving and engaging in behaviors indicative of in-group ties, cognitive centrality, and in-group affect (i.e., social identity) during a 3-day competitive ice hockey tournament. Forty-five youth (Mage = 12.39 years; SDage = 1.14 years; 94% male) from nine teams wore an electronically activated recorder that captured brief (50-s) audio observations throughout the tournament. Participants also completed daily diary questionnaires for each day of competition. Multilevel structural equation modeling demonstrated that athletes were more likely to engage in behaviors indicative of in-group affect and cognitive centrality on days when they received as higher-than-average frequency of behaviors indicative of cognitive centrality from teammates, coaches, and parents. The findings suggest that when team members interact in ways that demonstrate they are thinking about their team, they influence fellow members to behave in ways that promote a sense of "us."

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.

The effect of testosterone on economic risk-taking: A multi-study, multi-method investigation.

Testosterone has been suggested to influence individuals' economic decision making, yet the effects of testosterone on economic behavior are not well-understood and existing research is equivocal. In response, in three studies, we examined the extent to which testosterone affected or was associated with several different facets of economic decision making. Study 1 was a double-blind, placebo-controlled, within-subjects study examining loss aversion and risk-taking (N = 26), whereas Study 2 was a larger double-blind, placebo-controlled, between-subjects study examining loss aversion and risk-taking behavior (N = 117). As a methodological compliment, Study 3 was a larger correlational design (N = 213) with a highly accurate measure of endogenous testosterone examining a wider range of economic behaviors and trait-like preferences. Broadly, the results of all three studies suggest no consistent relationship between testosterone and financial behavior or preferences. Although there were significant effects in specific cases, these findings did not replicate in other studies or would not remain significant when controlling for family-wise error rate. We consider potential contextual moderators that may determine under what circumstances testosterone affects economic decision making.

Exploratory Analysis of the Relationship between Social Identification and Testosterone Reactivity to Vicarious Combat.

Testosterone (T) fluctuates in response to competitive social interactions, with the direction of change typically depending on factors such as contest outcome. Watching a competition may be sufficient to activate T among fans and others who are invested in the outcome. This study explores the change in T associated with vicarious experiences of competition among combat sport athletes viewing a teammate win or lose and assesses how individual differences in social identification with one's team relates to these patterns of T reactivity. Twenty-six male combat athletes completed a social identity questionnaire on a neutral day. Later, salivary samples (assayed for T) were obtained before and after athletes viewed a video of a teammate engaged in a formal contest. T reactivity to viewing a teammate compete varied among participants in both the magnitude and direction of change, independent of contest outcome. Individual differences in cognitive centrality, a core feature of social identification, showed a strong positive relationship with T reactivity, particularly if their teammate won. Initial findings suggest that dominance-linked androgen responses associated with watching a teammate win a competition might depend on the belief that team membership is central to one's own identity. These exploratory results in a small sample of combat athletes should be interpreted with caution. Uncovering the role of social group dynamics in influencing T responses to competition is particularly important in light of the evolutionary history of coalitional combat in humans.

Testosterone therapy masculinizes speech and gender presentation in transgender men.

Voice is one of the most noticeably dimorphic traits in humans and plays a central role in gender presentation. Transgender males seeking to align internal identity and external gender expression frequently undergo testosterone (T) therapy to masculinize their voices and other traits. We aimed to determine the importance of changes in vocal masculinity for transgender men and to determine the effectiveness of T therapy at masculinizing three speech parameters: fundamental frequency (i.e., pitch) mean and variation (fo and fo-SD) and estimated vocal tract length (VTL) derived from formant frequencies. Thirty transgender men aged 20 to 40 rated their satisfaction with traits prior to and after T therapy and contributed speech samples and salivary T. Similar-aged cisgender men and women contributed speech samples for comparison. We show that transmen viewed voice change as critical to transition success compared to other masculine traits. However, T therapy may not be sufficient to fully masculinize speech: while fo and fo-SD were largely indistinguishable from cismen, VTL was intermediate between cismen and ciswomen. fo was correlated with salivary T, and VTL associated with T therapy duration. This argues for additional approaches, such as behavior therapy and/or longer duration of hormone therapy, to improve speech transition.

Relationships between ovarian hormone concentrations and mental rotations performance in naturally-cycling women.

Circulating gonadal hormones have been linked to variation in the structure and function of the adult human brain, raising the question of how cognition is affected by sex hormones in adulthood. The impacts of progestogens and estrogens are of special interest due to the widespread use of hormone supplementation. Multiple studies have analyzed relationships between ovarian hormones and mental rotation performance, one of the largest known cognitive sex differences; however, results are conflicting. These discrepancies are likely due in part to modest sample sizes and reliance on self-report measures to assess menstrual cycle phase. The present study aimed to clarify the impact of progestogens and estrogens on visuospatial cognition by relating mental rotation task performance to salivary hormone concentrations. Across two studies totaling 528 naturally-cycling premenopausal women, an internal meta-analysis suggested a small, positive effect of within-subjects changes in progesterone on MRT performance (estimate = 0.44, p = 0.014), though this result should be interpreted with caution given multiple statistical analyses. Between-subjects differences and within-subject changes in estradiol did not significantly predict MRT. These results shed light on the potential cognitive effects of endogenous and exogenous hormone action, and the proximate mechanisms modulating spatial cognition.

Pubertal timing predicts adult psychosexuality: Evidence from typically developing adults and adults with isolated GnRH deficiency.

Evidence suggests that psychosexuality in humans is modulated by both organizational effects of prenatal and peripubertal sex steroid hormones, and by activational effects of circulating hormones in adulthood. Experimental work in male rodents indicates that sensitivity to androgen-driven organization of sexual motivation decreases across the pubertal window, such that earlier puberty leads to greater sex-typicality. We test this hypothesis in typically developing men (n = 231) and women (n = 648), and in men (n = 72) and women (n = 32) with isolated GnRH deficiency (IGD), in whom the precise timing of peripubertal hormone exposure can be ascertained via the age at which hormone replacement therapy (HRT) was initiated. Psychosexuality was measured with the Sexual Desire Inventory-2 (SDI-2) and Sociosexual Orientation Inventory-Revised (SOI-R). In both sexes, earlier recalled absolute pubertal timing predicted higher psychosexuality in adulthood, although the magnitude of these associations varied with psychosexuality type and group (i.e., typically developing and IGD). Results were robust when controlling for circulating steroid hormones in typically developing participants. Age of initiation of HRT in men with IGD negatively predicted SOI-R. We discuss the clinical implications of our findings for conditions in which pubertal timing is medically altered.

Testosterone administration in human social neuroendocrinology: Past, present, and future.

Over the past 20 years, social neuroendocrinology researchers have developed pharmacological challenge paradigms to assess the extent to which testosterone plays a causal role in human psychological and behavioural processes. The current paper provides a brief summary of this research and offers recommendations for future research examining the neuroendocrine mechanisms underlying human behaviour.

Testosterone, cortisol, and secretory immunoglobulin-A within a single day and across two sequential days among trans- and cis-gender men.

BACKGROUND: Previous research on the association between testosterone (T) and immunity has produced conflicting results. OBJECTIVES: We address two potential reasons for these empirical inconsistencies in the present research. First, the association between T and immunity may depend on which branch of the immune system is considered. Here, we examine secretory IgA (sIgA), a measure of mucosal immunity functionally related to respiratory infection risk. Second, the association between T and immunity may depend on a third regulatory variable. Therefore, we examine the interaction between T and cortisol (CORT) as well as their independent and combined effects on mucosal immunity. To do this, we explore intra-individual associations between sIgA, CORT, and T within a single day (i.e., morning vs. evening) and across 2 sequential mornings. We target two samples of men: (1) cisgender (i.e., born and identifying as men), and (2) transgender (i.e., born female but identifying as men) undergoing T therapy for gender realignment. MATERIALS AND METHODS: One hundred and forty-eight adult men (transgender n = 29) provided saliva samples at three time points: (1) upon waking, (2) before sleep on the same day, and (3) upon waking the following day. Samples were assayed in duplicate for sIgA, T and CORT. RESULTS: For cisgender men, sIgA, T, and CORT exhibited clear circadian rhythms and were significantly related within and between samples. For transgender men, evidence for circadian change was found for sIgA and CORT, but not T. Further, sIgA was associated with CORT, but not T. DISCUSSION AND CONCLUSIONS: This study provides the first evidence that salivary T and sIgA concentrations are associated within a single day and across sequential days for cisgender men. Differences between cis- and transgender men suggest that this may only be true for T levels driven by endogenous production; however, future studies should employ a larger sample size.

Facing off with the phalangeal phenomenon and editorial policies: A commentary on Swift-Gallant, Johnson, Di Rita and Breedlove (2020).

Swift-Gallant et al. (2020) provide a thought-provoking perspective on the topic of digit ratio research, research that has had some prominence in the journal Hormones and Behavior, and is research that has garnered much controversy. In this commentary on their paper, we add to the discussion of why there is skepticism of the use of digit ratios as a measure of individual differences in prenatal androgens, we comment on the mis-use of the facial width-to-height ratio as a measure of individual differences in testosterone, the grey areas in the interpretation of evidence, and we address the concern raised in their article regarding editorial policies at Hormones and Behavior (spoiler alert: there are no secret policies).

Does testosterone impair men's cognitive empathy? Evidence from two large-scale randomized controlled trials.

The capacity to infer others' mental states (known as 'mind reading' and 'cognitive empathy') is essential for social interactions across species, and its impairment characterizes psychopathological conditions such as autism spectrum disorder and schizophrenia. Previous studies reported that testosterone administration impaired cognitive empathy in healthy humans, and that a putative biomarker of prenatal testosterone exposure (finger digit ratios) moderated the effect. However, empirical support for the relationship has relied on small sample studies with mixed evidence. We investigate the reliability and generalizability of the relationship in two large-scale double-blind placebo-controlled experiments in young men (n = 243 and n = 400), using two different testosterone administration protocols. We find no evidence that cognitive empathy is impaired by testosterone administration or associated with digit ratios. With an unprecedented combined sample size, these results counter current theories and previous high-profile reports, and demonstrate that previous investigations of this topic have been statistically underpowered.

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.

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.

Using a Psychopharmacogenetic Approach To Identify the Pathways Through Which-and the People for Whom-Testosterone Promotes Aggression.

Little is known about the neurobiological pathways through which testosterone promotes aggression or about the people in whom this effect is observed. Using a psychopharmacogenetic approach, we found that testosterone increases aggression in men ( N = 308) with select personality profiles and that these effects are further enhanced among those with fewer cytosine-adenine-guanine (CAG) repeats in exon 1 of the androgen receptor (AR) gene, a polymorphism associated with increased AR efficiency. Testosterone's effects were rapid (~30 min after administration) and mediated, in part, by subjective reward associated with aggression. Testosterone thus appears to promote human aggression through an AR-related mechanism and to have stronger effects in men with the select personality profiles because it more strongly upregulates the subjective pleasure they derive from aggression. Given other evidence that testosterone regulates reward through dopaminergic pathways, and that the sensitivity of such pathways is enhanced among individuals with the personality profiles we identified, our findings may also implicate dopaminergic processes in testosterone's heterogeneous effects on aggression.

Taking risks for personal gain: An investigation of self-construal and testosterone responses to competition.

Recent research on testosterone and risk-taking behavior is beginning to focus on the role of context-dependent changes in testosterone. Extending this research, our study investigated the association between testosterone reactivity to competitive outcomes and risk-taking in the context of a video game based competition. The study also examined whether self-construal moderated this relationship. Results indicated that a rise in testosterone during competition did not predict subsequent risk-taking behavior. However, a rise in testosterone during competition predicted subsequent risk-taking behaviors within winners with independent self-construals. Nevertheless, results did not reveal an association between basal testosterone and risk-taking, nor did competitive outcomes modulate a differential testosterone response. Overall, we treat these findings as preliminary, as there were multiple analyses conducted and effect sizes were relatively small. We discuss these results in the context of recent animal findings that testosterone facilitates success at future competitions after winning a competition, as well as recent research suggesting self-construal moderates associations between testosterone and aggression.