1,453 research outputs found

    An X-ray Investigation of the Crystal Structure of Meta- Azotoluene

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    Beyond the challenge hypothesis: The emergence of the dual-hormone hypothesis and recommendations for future research

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

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

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    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 (20 minutes post-stressor). Results revealed a positive association between basal t estosterone 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

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

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    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

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

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    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

    The causal effect of testosterone on men’s competitive behavior is moderated by basal cortisol and cues to an opponent’s status: Evidence for a context-dependent dual hormone hypothesis

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    Testosterone has been theorized to direct status-seeking behaviors, including competitive behavior. However, most human studies to date have adopted correlational designs, and findings across studies are inconsistent. This experiment (n = 115) pharmacologically manipulated men’s testosterone levels prior to a mixed-gender math competition and examined basal cortisol (a hormone implicated in stress and social avoidance) and context cues related to an opponent’s perceived status (an opponent’s gender or a win/loss in a prior competition) as factors that may moderate testosterone’s impact on competitive behavior. We test and find support for the hypothesis that testosterone given to low-cortisol men evokes status-seeking behavior, whereas testosterone given to high-cortisol men evokes status-loss avoidance. In the initial rounds of competition, testosterone’s influence on competitive decisions depended on basal cortisol and opponent gender. After providing opponent-specific win-lose feedback, testosterone’s influence on decisions to re-enter competitions depended on basal cortisol and this objective cue to status, not gender. Compared to placebo, men given exogenous testosterone who were low in basal cortisol showed an increased tendency to compete against male and high-status opponents relative to female and low-status opponents (status-seeking). Men given exogenous testosterone who were high in basal cortisol showed the opposite pattern - an increased tendency to compete against female and low-status opponents relative to male and high-status opponents (status-loss avoidance). These results provide support for a context-dependent dual hormone hypothesis: Testosterone flexibly directs men’s competitive behavior contingent on basal cortisol levels and cues that signal an opponent’s status

    No Compelling Evidence that Self-Reported Personality Traits Explain Basal Testosterone and Cortisol’s Associations with Status-Relevant Behavior

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

    Correction to: No Compelling Evidence that Self-Reported Personality Traits Explain Basal Testosterone and Cortisol’s Associations with Status-Relevant Behavior

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    The originally published version of this article contained mistakes. The article note that can be found in the first page of the published article that says “These authors contributed equally” should be changed to “The first two authors contributed equally to this work”

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

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    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

    The subconvexity problem for \GL_{2}

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    Generalizing and unifying prior results, we solve the subconvexity problem for the LL-functions of \GL_{1} and \GL_{2} automorphic representations over a fixed number field, uniformly in all aspects. A novel feature of the present method is the softness of our arguments; this is largely due to a consistent use of canonically normalized period relations, such as those supplied by the work of Waldspurger and Ichino--Ikeda.Comment: Almost final version to appear in Publ. Math IHES. References updated
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