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A contribution to a special issue on Hormones and Human Competition. Psychoneuroendocrine effects of competition have been widely accepted as a clear example of the relationship between androgens and aggressive/dominant behavior in humans. However, results about the effects of competitive outcomes are quite heterogeneous, suggesting that personal and contextual factors play a moderating role in this relationship. To further explore these dimensions, we aimed to examine (i) the effect of competition and its outcome on the psychobiological response to a laboratory competition in young men, and (ii) the moderating role of some cognitive dimensions such as causal attributions. To do so, we compared the responses of 56 healthy young men faced with two competitive tasks with different instructions. Twenty-eight men carried out a task whose instructions led subjects to think the outcome was due to their personal performance (“merit” task), whereas 28 other men faced a task whose outcome was attributable to luck (“chance” task). In both cases, outcome was manipulated by the experimenter. Salivary steroid hormones (testosterone and cortisol), cardiovascular variables (heart rate and blood pressure), and emotional state (mood and anxiety) were measured at different moments before, during and after both tasks. Our results did not support the “winner-loser effect” because no significant differences were found in the responses of winners and losers. However, significantly higher values on the testosterone and cardiovascular variables, along with slight decreases in positive mood, were associated with the merit-based competition, but not the chance-based condition. In addition, an exploratory factorial analysis grouped the response components into two patterns traditionally related to more active or more passive behaviors. Thus, our results suggest that the perception of contributing to the outcome is relevant in the psychobiological response to competition in men. Overall, our results reveal the importance of the appraisal of control and causal attribution in understanding human competitive interactions.

We previously reported that glucose intake amplifies cortisol response to psychosocial stress and smoking in healthy young men, while low blood glucose levels prevented the stress-induced activation of the hypothalamus pituitary adrenal (HPA) axis. However, it remains unknown whether this modulation is specific for glucose load or a more common effect of energy availability. To elucidate this question, 37 healthy men, who fasted for at least 8 h before the experiment, were randomly assigned to four experimental groups, who received glucose (n = 8), protein (n = 10), fat (n = 10), and water (n = 9), one h before their exposure to the Trier Social Stress Test (TSST). Blood glucose levels were measured at baseline and following stress, while salivary cortisol was assessed repeatedly measured before after the TSST. The results show that both absolute cortisol levels and net cortisol increase were greater in the glucose group in comparison to the other groups (F(3,33) = 3.00, P0.05 and F(3,33) = 3.08, P0.05, respectively. No group differences were observed with respect to perceived stress and mood. Furthermore, the cortisol response was positively correlated with blood glucose changes (r = 0.49, P0.002). In conclusion, the results suggest a central mechanism responsible for regulation of energy balance and HPA axis activation, rather than peripheral mechanisms. We thus recommend controlling for blood glucose levels when studying HPA axis responsiveness.

In 1 humans, hormonal responses to winning/losing and their relationships to mood and status change have mostly been examined in individual athletic competitions. In this study, the salivary testosterone (T) and cortisol (C) and mood responses to a real match between two professional basketball teams were investigated. Data about individuals’ contributions to outcome, performance appraisal, and attribution of outcome to internal/external factors were also collected. Results did not show statistically significant different T and C responses depending on the outcome. Negative mood was significantly enhanced, especially in the losers, while winners showed a better appraisal of team performance and a more internal attribution. T response did not show a significant relationship with mood changes, but it correlated positively with the “score/time playing” ratio, an indicator of individual participation in the outcome. Furthermore, T response correlated negatively with external attribution in winners and positively in losers. These results indicate that in a real, highly competitive situation, T changes are not directly a response to the outcome, but rather to the contribution the individual makes to it and to the causes he attributes. © 1999 Academic Press

In the caregiving model of chronic stress, few studies have been conducted with young middle-aged samples and no data exists about acute stress response in this population. To extend knowledge in this issue, health complaints and psychological, endocrine, and immunological responses to stress have been assessed in a cross-sectional sample of 41 parents of offspring with autistic spectrum disorder (ASD) in comparison with 37 non-caregiver parents. Salivary cortisol and immunoglobulin A (IgA) levels were measured before, during, and after a mental psychosocial stressor, while mood and state anxiety were evaluated before and after the stress. Health complaints, personality traits, socio-economic status, and characteristics of the care recipient were assessed. Caregivers reported more health complaints showing buffered cortisol and IgA responses and greater increases in fatigue to acute stress than the controls. In terms of predictive power of health complaints, IgA levels, care status, and severity of the care recipient are especially relevant for caregivers. Results strongly suggest a dysregulation in the immune and hormonal stress-induced responses in middle-aged caregivers, with immune component and care characteristics as the main modulators of health complaints. A deficit in the adaptive capability of stress response is plausible in this population, emphasizing the need to consider family approaches when planning protocols for assistance to ASD patients.

As a continuation of the study carried out by Svare more than 15 years ago (Horm. Behav. 22 (1988), 139) and to determine the tendencies of the evolution of behavioral endocrinology since then, our aim was to extend his work until 2000, assuming that the journal Hormones and Behavior would be representative of the field at large. To study this 14-year period and compare it with Svare's data, we kept the same criteria and categories, behavioral patterns, and species. Our results show that "sexual behavior" in "rodents" is still the most extensive field studied by behavioral endocrinologists, although frequency of other topics is increasing, above all "aggressive and emotional responses," and especially the interrelationships between them. Interestingly, studies dedicated to humans are slowly becoming more common. In addition to these analyses, we obtained the several citations received by a randomly selected sample of articles during the period that was divided by the number of years when the articles can be potentially cited. These ratios revealed that research on "humans," within the category of species, and on "memory, learning, and conditioning" and "aggressive and emotional responses," within the behavioral categories, present the highest visibility in the literature. Furthermore, this analysis was complemented with information about the main receptor journals of the papers published in Hormones and Behavior, classified by the same categories. All these data, although limited by the analysis of only one journal, permitted us to reflect on whether the evolution tendencies formulated by Beach (Horm. Behav. 15 (1981), 325) for this discipline were applicable to the period studied, thus confirming its status as a mature discipline for the last quarter of the 20th century.