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1.
Horm Behav ; 164: 105608, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39053138

RESUMO

Testosterone production in women is thought to systematically shift across the menstrual cycle, peaking during the mid-cycle ovulatory window, and potentially influencing women's behavior. Testosterone is a molecular intermediary to the production of estradiol, which is necessary for ovulation to occur, but the amount of testosterone escape and exposure to the peripheral tissues is not fully understood. Salivary testosterone is a common biomarker in behavioral neuroendocrinological studies and is thought to reflect the bioactive portions in serum. In N = 339 women with confirmed ovulation via luteinizing hormone tests, salivary testosterone, assayed with LC-MS/MS, was sampled four times across the mid-cycle ovulatory window the luteal phase. Within-subject analysis revealed a significant but small pattern of a mid-cycle peak and a luteal decrease at the aggregate level. However, at the individual level, there was substantial variability in the direction and magnitude of the testosterone-cycle pattern. We discuss the relevant underlying physiology, background research, issues with assay methodolody, and considerations for researchers studying testosterone levels in women.


Assuntos
Ciclo Menstrual , Saliva , Testosterona , Humanos , Feminino , Saliva/química , Saliva/metabolismo , Testosterona/análise , Testosterona/metabolismo , Ciclo Menstrual/fisiologia , Adulto , Adulto Jovem , Adolescente
2.
Horm Behav ; 162: 105540, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38652981

RESUMO

Sex/gender differences in personality associated with gender stereotyped behavior are widely studied in psychology yet remain a subject of ongoing debate. Exposure to testosterone during developmental periods is considered to be a primary mediator of many sex/gender differences in behavior. Extensions of this research has led to both lay beliefs and initial research about individual differences in basal testosterone in adulthood relating to "masculine" personality. In this study, we explored the relationships between testosterone, gender identity, and gender stereotyped personality attributes in a sample of over 400 university students (65 % female assigned at birth). Participants provided ratings of their self-perceived masculinity and femininity, resulting in a continuous measure of gender identity, and a set of agentic and communal personality attributes. A saliva sample was also provided for assay of basal testosterone. Results showed no compelling evidence that basal testosterone correlates with gender-stereotyped personality attributes or explains the relationship between sex/gender identity and these attributes, across, within, or covarying out sex assigned at birth. Contributing to a more gender diverse approach to assessing sex/gender relationships with personality and testosterone, our continuous measure of self-perceived masculinity and femininity predicted additional variance in personality beyond binary sex and showed some preliminary but weak relationships with testosterone. Results from this study cast doubt on the activational testosterone-masculinity hypothesis for explaining sex differences in gender stereotyped traits and within-sex/gender variation in attributes associated with agency and communality.


Assuntos
Identidade de Gênero , Personalidade , Testosterona , Humanos , Masculino , Feminino , Personalidade/fisiologia , Adulto Jovem , Adulto , Estereotipagem , Adolescente , Masculinidade , Saliva/química , Saliva/metabolismo , Feminilidade , Autoimagem , Caracteres Sexuais
3.
Front Neuroendocrinol ; 67: 101036, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36126748

RESUMO

Oral contraceptives (OCs) are widely used yet understudied given their potential for public health consequences. Emerging investigations scaling from single-subject, dense-sampling neuroimaging studies to population-level metrics have linked OCs to altered brain structure and function. Modeling the hypogonadal, hypergonadal, or mixed state effects of OCs in terms of their impact on hormone action in the brain is a valuable approach to synthesizing results across neuroimaging studies and comparing OC effects to companion findings from research on menstrual cycle phase effects on brain anatomy and function. Resting-state functional connectivity studies provide a powerful tool to evaluate the role of OCs on the intrinsic network connectivity that underlies multiple behavioral domains. The preponderance (but not consensus) of the current literature indicates that (1) as the menstrual cycle proceeds from a low to high progesterone state, prefrontal connectivity increases and parietal connectivity decreases; (2) OCs tend to mimic this connectivity pattern; therefore (3) OCs may produce a hyperprogestogenic state in the brain, in spite of overall reductions in endogenous steroid hormone levels. Alternative models are also considered.


Assuntos
Anticoncepcionais , Ciclo Menstrual , Feminino , Humanos , Hormônios , Progesterona , Encéfalo/diagnóstico por imagem
4.
Front Neuroendocrinol ; 66: 101015, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35835214

RESUMO

Emerging evidence suggests that hormonal contraceptives (HCs) impact psychological outcomes through alterations in neurophysiology. In this review, we first introduce a theoretical framework for HCs as disruptors of steroid hormone modulation of socially competitive attitudes and behaviors. Then, we comprehensively examine prior research comparing HC users and non-users in outcomes related to competition for reproductive, social, and financial resources. Synthesis of 46 studies (n = 16,290) led to several key conclusions: HC users do not show the same menstrual cycle-related fluctuations in self-perceived attractiveness and some intrasexual competition seen in naturally-cycling women and, further, may show relatively reduced status- or achievement-oriented competitive motivation. However, there a lack of consistent or compelling evidence that HC users and non-users differ in competitive behavior or attitudes for mates or financial resources. These conclusions are tentative given the notable methodological limitations of the studies reviewed. Implications and recommendations for future research are discussed.


Assuntos
Comportamento Competitivo , Anticoncepcionais Orais Hormonais , Comportamento Competitivo/fisiologia , Feminino , Hormônios , Humanos , Ciclo Menstrual/fisiologia , Motivação , Progesterona
5.
J Undergrad Neurosci Educ ; 20(2): A191-A206, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-38323054

RESUMO

Offering courses on the neuroscience of sex and gender can help support an inclusive curriculum in neuroscience. At the same time, developing and teaching such courses can be daunting to even the most enthusiastic educators, given the subject's complexities, nuances, and the difficult conversations that it invites. The authors of this article have all developed and taught such courses from different perspectives. Our aim is to provide educators with an overview of important conceptual topics as well as a comprehensive, but non-exhaustive, guide to resources for teaching about sex/gender in neuroscience based on our collective experience teaching courses on the topic. After defining vital terminology and briefly reviewing the biology of sex and sex determination, we describe some common topics within the field and contrast our current nuanced understandings from outdated misconceptions in the field. We review how (mis)representation of the neuroscience of sex/gender serves as a case study for how scientific results are communicated and disseminated. We consider how contextualization of sex/gender neuroscience research within a broader historical and societal framework can give students a wider perspective on the enterprise of science. Finally, we conclude with a brief discussion on how to choose learning goals for your course and implementation notes.

6.
Horm Behav ; 129: 104921, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33428922

RESUMO

The results of a recent study, Félix et al., 2020, give new information about the behavioral and endocrine correlates of individual differences in the potential for androgen response in male cichlid fish. We think the study raises issues that are pertinent to the study of hormones and competition in other species, particularly humans. Focusing mostly on androgen reactivity to social challenge, we emphasize the importance of inter-individual variability in physiology, personality, and motivation in studies of hormone responses to social encounters. Additionally, we give special attention to matters of "repeatability" and the timing of hormone sampling. We conclude with an appreciation of the value of comparative analysis in behavioral endocrinology.


Assuntos
Ciclídeos , Testosterona , Androgênios , Animais , Sistema Endócrino , Humanos , Individualidade , Masculino
8.
Horm Behav ; 92: 29-36, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28527589

RESUMO

Thirty-five women participating in one or more intramural flag-football games provided saliva samples before, immediately after, and 10min after competition and completed an after-competition questionnaire appraising their own performance during the game. As seen in other studies of elite athletes, these recreational athletes, on average, showed significant elevations in testosterone (T) and cortisol (C) across the competition period - the "competition effect". In winners and losers, T levels at all time points measured were positively related to athletes' appraisals of their own individual performance. Results from this study show that the competition effect for T and C is evident in recreational women athletes and provide preliminary evidence about the relationship between cognitive appraisal and competition-related T levels.


Assuntos
Logro , Atletas/psicologia , Comportamento Competitivo/fisiologia , Hidrocortisona/análise , Testosterona/análise , Adulto , Feminino , Humanos , Saliva/química
9.
Horm Behav ; 82: 21-37, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27103058

RESUMO

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.


Assuntos
Comportamento Competitivo/fisiologia , Hidrocortisona/metabolismo , Testosterona/metabolismo , Afeto/fisiologia , Agressão/fisiologia , Feminino , Humanos , Hidrocortisona/fisiologia , Masculino , Motivação/fisiologia , Percepção/fisiologia , Saliva/metabolismo , Testosterona/fisiologia
10.
Horm Behav ; 64(1): 153-60, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23523743

RESUMO

Recent research suggests that testosterone and cortisol jointly regulate dominance motivation and, perhaps, the status relationships that are affected by it. For this article, the results of six different studies of women's intercollegiate athletic competition were combined to give a sample size of almost ninety women for whom we had before- and after-competition values for salivary cortisol and testosterone for at least one and sometimes two competitions. For many of these women, we had surveys that allowed us to assess their status with teammates. In no matter what sport (soccer, softball, volleyball, and tennis) levels of salivary cortisol and testosterone increased when women participated in athletic competition. Salivary levels of C and T appear to rise in parallel during competition and increases in levels of one hormone are significantly related to increases in the other. Salivary levels of these hormones typically decreased for teammates who did not play but watched the competition from the sidelines. For women who played in two competitions, individual differences in the positive effect of competition on cortisol and testosterone were conserved from one competition to the next, affirming the personal consistency of endocrine responses to competition. Status with teammates was positively related to before-competition levels of testosterone, but only for women with relatively low before-competition levels of cortisol. This result provides novel support for the "dual-hormone hypothesis" as it relates to predicting social status in women's athletic teams - natural social groups of individuals who know each other and whose social hierarchy has evolved over the course of practice and play for at least one and, in some cases, several years of intercollegiate athletic competition.


Assuntos
Comportamento Competitivo/fisiologia , Hidrocortisona/fisiologia , Predomínio Social , Esportes/fisiologia , Testosterona/fisiologia , Mulheres , Desempenho Atlético/fisiologia , Beisebol/fisiologia , Sistema Endócrino , Feminino , Humanos , Hidrocortisona/metabolismo , Individualidade , Saliva/química , Saliva/metabolismo , Futebol/fisiologia , Tênis/fisiologia , Testosterona/metabolismo , Voleibol/fisiologia , Adulto Jovem
11.
Psychoneuroendocrinology ; 157: 106367, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37639799

RESUMO

Early evidence suggests that hormonal contraceptive (HC) use alters psychological functioning and competitive behavior. Yet, there is limited data on endocrine models for explaining how HC use affects these outcomes. In this pre-registered and open-data study, we test if HC users and naturally cycling (NC) females in their low (mid-follicular) and high (mid-luteal) progesterone phase differ in competitive persistence and whether progesterone and cortisol reactivity mediate of this effect. HC users (N = 73) in the active hormone-exposure phase and NC participants in the mid-follicular (N = 69) or mid-luteal (N = 72) phase completed two behavioral measures of competitive persistence, holding up a weight for time followed by attempting to solve an unsolvable anagram. Participants also completed measures of handgrip strength and self-reported competitiveness as well as gave saliva samples before and after the tasks for hormone assay. Results showed that NC-follicular group had greater competitive persistence in the weight-holding task compared to both NC-luteal (d = 0.38) and HC use (d = 0.43) groups independent of physical strength and self-reported competitiveness covariates. Although anagram task performance showed similar trends for group differences, analyses for this task were inconclusive. Baseline progesterone did not mediate the effect of cycle phase group on competitive persistence. HC users showed relatively blunted cortisol and progesterone reactivity, and this effect partially mediated the difference in competitive persistence between HC users and the NC-follicular group. In sum, results suggest that HC use could downregulate competitive behavior at least partly by dampening cortisol-progesterone reactivity. These findings offer a new endocrine model for understanding HC use and cycle phase effects on motivational and energetic outcomes required for optimal performance in competitive contexts.


Assuntos
Fase Folicular , Progesterona , Feminino , Humanos , Progesterona/farmacologia , Hidrocortisona/farmacologia , Ciclo Menstrual/fisiologia , Anticoncepcionais , Força da Mão , Estradiol/farmacologia
14.
Hum Nat ; 32(2): 509-527, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34231127

RESUMO

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.


Assuntos
Identificação Social , Esportes , Comportamento Competitivo , Humanos , Masculino , Saliva , Inquéritos e Questionários , Testosterona
17.
Physiol Behav ; 142: 48-51, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25647361

RESUMO

Recent research suggests that cortisol (C) level moderates testosterone (T) reactivity to the Trier Social Stress Test (TSST) in men. The extent to which C moderates T reactivity in other circumstances and in women is not known. In this retrospective study, before- and after-competition salivary levels of C and T from 97 intercollegiate women athletes competing in one of four different sports (soccer, volleyball, softball, tennis) were used to evaluate the influence of before-competition C level on T reactivity in women's athletic competition. Athletic competition was associated with a substantial increase in salivary levels of C and T in the vast majority of athletes. Before-competition level of C significantly moderated testosterone reactivity to athletic competition - women with relatively low levels of C showed larger increases in T to competition than women with higher levels of C. Clearly, the moderating effect of C on T reactivity is not limited to laboratory settings intended to increase social stress, but is also seen in (as we show here) the context of athletic competition.


Assuntos
Atletas , Hidrocortisona/metabolismo , Saliva/metabolismo , Testosterona/metabolismo , Beisebol/fisiologia , Comportamento Competitivo/fisiologia , Feminino , Humanos , Estudos Retrospectivos , Futebol/fisiologia , Estresse Psicológico/metabolismo , Tênis/fisiologia , Universidades , Voleibol/fisiologia
18.
Physiol Behav ; 147: 84-90, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25866255

RESUMO

This study examined the salivary testosterone (T) and cortisol (C) responses of elite women hockey players across 4 activities (light and heavy training, club and International competitions). The players formed an oral contraceptive (OC) group (n=10) and a Non-OC (n=19) group for analysis. The Non-OC group had higher T levels (by 31-52%) across all activities, whilst the OC group showed signs of reduced T and C reactivity when data were pooled. As a squad, positive T and C changes occurred with heavy training (45%, 46%), club competitions (62%, 80%) and International competitions (40%, 27%), respectively. Our results confirm that OC use lowers T levels in women athletes whilst reducing the T and C responses to training and competition activities within the sporting environment. Differences in the physical and/or psychological demands of the sporting activity could be contributing factors to the observed hormone responses. These factors require consideration when applying theoretical models in sport, with broader implications for women around exercising behaviours and stress physiology.


Assuntos
Anticoncepcionais Orais/farmacologia , Hidrocortisona/metabolismo , Saliva/efeitos dos fármacos , Saliva/metabolismo , Ensino , Testosterona/metabolismo , Adulto , Atletas , Comportamento Competitivo/fisiologia , Feminino , Hóquei , Humanos , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Fatores de Tempo , Adulto Jovem
19.
Int J Exerc Sci ; 5(1): 60-71, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-27182375

RESUMO

This study attempts to determine whether the presentation of an experimentally manipulated somatic experience during a physically strenuous task can influence physical performance and symptom reporting. The study also compares the relative influence of experimentally manipulated somatic information (state somatization) with stable individual differences in the tendency to amplify physical symptoms (trait somatization) on performance and symptom reporting. 194 participants completed standardized measures of somatization tendencies, state anxiety, neuroticism and conscientiousness. Participants where then given a mock physical exam, with individuals randomly assigned to receive either favorable or unfavorable somatic information. All participants then had their body mass index assessed and completed a rigorous exercise task, with quantification of performance. Physiological measures of blood pressure and pulse were also assessed before and after the exercise task. The experimentally manipulated presentation of somatic information predicted both performance and physical symptoms, even after controlling for BMI, neuroticism, conscientiousness, and state anxiety. Moreover, expected performance uniquely and significantly predicted performance above and beyond condition, anxiety, BMI, neuroticism, and conscientiousness. Somatosensory amplification tendencies also predicted symptom endorsement, but not performance. Findings suggest that both state and trait expectations with respect to somatic experiences influence symptom reporting and to a lesser extent performance, even after controlling for variables known to strongly influence each of these outcomes. Results are consistent with the cognitive-perceptual and the cognitive-appraisal models of somatic interpretation.

20.
Org Lett ; 13(20): 5444-7, 2011 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-21957974

RESUMO

Aziridines are important synthetic intermediates which readily undergo ring-opening reactions. It is demonstrated that electron-rich phosphines are efficient catalysts for the regioselective rearrangement of N-acylaziridines to oxazolines. The reactions occur in excellent yield under neutral conditions. Evidence is provided for an addition/elimination mechanism by generation of a phosphonium intermediate. Similar intermediates may be useful for the development of alternate aziridine ring-opening processes and stereoselective synthesis with enantiopure phosphines.

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