Keith M. Welker

A comparison of salivary testosterone measurement using immunoassays and tandem mass spectrometry

Enzyme immunoassays (EIAs) are widely used to measure salivary testosterone. However, little is known about how accurately different EIAs assess testosterone, partially because estimates across various EIAs differ considerably. We compared testosterone concentrations across EIAs of three commonly used manufacturers (DRG International, Salimetrics, and IBL International) to liquid chromatography tandem mass spectrometry (LC-MS/MS). Relative to EIAs from Salimetrics and IBL International, EIAs supplied by DRG International provided the closest approximation to LC-MS/MS testosterone concentrations, followed closely by EIAs from Salimetrics, and then IBL. Additionally, EIAs tended to inflate estimates of lower testosterone concentrations in women. Examining our results and comparing them to existing data revealed that testosterone EIAs had decreased linear correspondence with LC-MS/MS in comparison to cortisol EIAs. Overall, this paper provides researchers with information to better measure testosterone in their research and more accurately compare testosterone measurements across different methods.

Preliminary evidence that testosterone's association with aggression depends on self-construal☆

Abstract A contribution to a special issue on Hormones and Human Competition. Previous research and theory suggest testosterone is an important hormone for modulating aggression and self‐regulation. We propose that self‐construal, a culturally‐relevant difference in how individuals define the self in relation to others, may be an important moderator of the relationship between testosterone and behaviors linked to aggression. Within two studies (Study 1 N = 80; Study 2 N = 237) and an integrated data analysis, we find evidence suggesting that acute testosterone changes in men are positively associated with aggressive behavior for those with more independent self‐construals, whereas basal testosterone is negatively associated with aggression when individuals have more interdependent self‐construals. Although preliminary, these findings suggest that self‐construal moderates the association between testosterone and aggression, thereby paving the way toward future work examining the potential cultural moderation of the behavioral effects of testosterone. HighlightsSelf‐construal moderates how mens testosterone is associated with aggression.Basal testosterone negatively predicted aggression in interdependent men.Testosterone reactivity to competition predicted aggression in independent men.These findings suggest cultural differences may alter how testosterone is linked with behavior.

Commentary: Facial Width-to-Height Ratio (fWHR) Is Not Associated with Adolescent Testosterone Levels

Facial width-to-height ratio (fWHR), the ratio of the distance between the left and right zygomatic bones to the distance between the upper lip and brow, predicts many traits, displays, and behaviors, including male aggression, trustworthiness, risk-taking, and physical formidability (e.g., Carre et al., 2009; Stirrat and Perrett, 2010; Welker et al., 2015; Zilioli et al., 2015). One theorized mechanism for linking fWHR to these behavioral traits and displays is pubertal exposure to testosterone, which may reflect androgenic organizational effects on neural circuitry related to these behaviors (Carre and McCormick, 2008). Lending support to this possibility, some work suggests that low-dose administrations of testosterone modulate craniofacial growth in boys with delayed puberty (Verdonck et al., 1999), but until now, research has not examined this association.

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

ABSTRACT 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.

Does the Biosocial Model Explain the Emergence of Status Differences in Conversations among Unacquainted Men

Fifteen triads of unacquainted men conversed for ten minutes while stress was measured in real time by pulse rate and thumb blood volume (TBV). Salivary measures of testosterone (T), cortisol (C), and the stress-related enzyme alpha-amylase (AA) were measured at the beginning and end of the session. Fully or partially transitive status hierarchies formed in 14 triads. (Highest ranked man was scored 1, lowest 3, with ties allowed.) Ten of the triads participated in Study 1, where nothing was at stake in the casual conversation. Five additional triads were run in Study 2, intended to introduce competition by offering a

Social anxiety, cortisol, and early-stage friendship

20 reward to the man afterward chosen as having led the conversation. Most results from the two studies are similar, suggesting that the

5-HTTLPR polymorphism is associated with nostalgia proneness: The role of neuroticism

20 reward had little effect. Combining studies, pulse and TBV show that conversation is more stressful than watching a video beforehand. Within the conversation, speaking turns are more stressful than listening turns, especially among the lowest ranked men, less so among those higher in rank. This supports a stress-based mechanism for status allocation among humans. Apparently, human speech is a form of status signaling, homologous with nonlinguistic status signals used by other primates, as posited by the “biosocial model.” The biosocial model also posits that a physiological substrate (T, C, and AA) is related to dominance or status. Predicted effects are not replicated here, except for an inverse relationship between the stress enzyme AA and status. The mostly null results, obtained from conversations where there was little or nothing at stake, suggest that T and C (and their interaction) are not relevant to emergent status in the absence of serious competition.

Basal cortisol’s relation to testosterone changes may not be driven by social challenges

Socially anxious people report less closeness to others, but very little research has examined how social anxiety is related to closeness in real-time social interactions. The present study investigated social anxiety, closeness, and cortisol reactivity in zero-acquaintance interactions between 84 same-sex dyads (168 participants). Dyads engaged in either a high or low self-disclosure discussion task and completed self-report measures of closeness and desired closeness post-task. Salivary cortisol was collected before, during, and after the self-disclosure task. Multilevel models indicated that in the high self-disclosure condition, individuals higher in social anxiety displayed flatter declines in cortisol than those lower in social anxiety; cortisol declines were not significantly related to social anxiety in the low self-disclosure condition. Further, across both conditions, individual’s social anxiety was associated with decreased levels of closeness and desired closeness, particularly when individuals were paired with partners higher in social anxiety. These findings are discussed in relation to previous work on hypothalamic–pituitary–adrenal function, social anxiety, and interpersonal closeness.

Music as an emotion regulation strategy: An examination of genres of music and their roles in emotion regulation:

ABSTRACT Nostalgia, a sentimental longing for the past, is a self-relevant and social emotion. Nostalgia proneness is associated with alleviation of distress or instability (e.g., neuroticism). Although nostalgia proneness is heritable, the specific molecular contributors to this heritability are unknown. We focused on a polymorphism in the promoter of the serotonin transporter gene (5-HTTLPR) as a possible biological basis of nostalgia proneness, because the serotonin system has been associated with sensitivity to negative experience. Participants (N = 397 adults) who had reported levels of nostalgia proneness were genotyped. A subsample also completed a measure of neuroticism. Participants with the 5-HTTLPR short allele were higher on nostalgia proneness than those without this allele. Neuroticism mediated the relation between 5-HTTLPR and nostalgia proneness. These findings enrich our understanding of the genetic and personality underpinnings of nostalgia.

Does the facial width-to-height ratio map onto variability in men's testosterone concentrations?

Multiple studies show a negative correlation between basal cortisol and testosterone changes in the presence of competition and social-evaluative stressors. These negative associations are proposed to be derived from psychological responses to competition and social-evaluative stress. However, we argue that the association between basal cortisol and testosterone change may instead be a statistical consequence of positively associated variables. In this paper, we present a mathematical rationale for this alternative explanation and examples from two studies that are consistent with this alternative explanation. Both studies show that the associations between basal cortisol and testosterone change have covariance patterns consistent with this alternative possibility. We conclude that the often-found positive association between basal cortisol and basal testosterone opens the door for alternative explanations of the basal cortisol-testosterone change association rooted in the patterns of associations between hormones measured over time. We also suggest future research directions and methods for testing alternative explanations.