Implicit power motivation moderates men's testosterone responses to imagined and real dominance success

This study tested the hypothesis that implicit power motivation moderates individuals' testosterone responses to the anticipated success in and actual outcome of a dominance contest. Salivary testosterone levels were assessed in 42 male students at the beginning of the study, after they had imagined a success in an ensuing power contest, and immediately after the contest had taken place. Contest outcome (winning or losing against a competitor on a speed-based task) was varied experimentally. Participants' power motive was assessed with a picture-story exercise, in which an assertive, personalized (p Power) component was distinguished from an altruistic, socialized (s Power) component. In contrast to all other participants, individuals high only in p Power (a) had elevated testosterone after imagining a success in a subsequent dominance contest and (b) continued to have high testosterone levels after actually winning, but not after losing, the contest.     

Salivary cortisol changes in humans after winning or losing a dominance contest depend on implicit power motivation

In two studies, one with an all-male German sample and the other with a mixed-sex U.S. sample, subjects competed in pairs on reaction time-based cognitive tasks. Participants were not aware that contest outcome was experimentally varied. In both studies, implicit power motivation, defined as the non-conscious need to dominate or have impact on others, predicted changes in salivary cortisol from before to after the contest. Increased cortisol post-contest was associated with high levels of power motivation among losers but with low levels of power motivation among winners, suggesting that a dominance success is stressful for low-power individuals, whereas a social defeat is stressful for high-power individuals. These results emerged only in participants tested in the afternoon, possibly because of greater variability in cortisol in the morning due to the rapid decline after the morning peak. These studies add to the evidence that individual differences greatly influence whether a social stressor like losing a contest activates the HPA axis in humans.     

Basal and dynamic relationships between implicit power motivation and estradiol in women

This study investigated basal and reciprocal relationships between implicit power motivation (n Power), a preference for having impact and dominance over others, and both salivary estradiol and testosterone in women. 49 participants completed the Picture Story Exercise, a measure of n Power. During a laboratory contest, participants competed in pairs on a cognitive task and contest outcome (win vs. loss) was experimentally varied. Estradiol and testosterone levels were determined in saliva samples collected at baseline and several times post-contest, including 1 day post-contest. n Power was positively associated with basal estradiol concentrations. The positive correlation between n Power and basal estradiol was stronger in single women, women not taking oral contraceptives, or in women with low-CV estradiol samples than in the overall sample of women. Women's estradiol responses to a dominance contest were influenced by the interaction of n Power and contest outcome: estradiol increased in power-motivated winners but decreased in power-motivated losers. For power-motivated winners, elevated levels of estradiol were still present the day after the contest. Lastly, n Power and estradiol did not correlate with self-reported dominance and correlated negatively with self-reported aggression. Self-reported dominance and aggression did not predict estradiol changes as a function of contest outcome. Overall, n Power did not predict basal testosterone levels or testosterone changes as a function of dominance contest outcome.     

Basal and dynamic relationships between implicit power motivation and estradiol in women

This study investigated basal and reciprocal relationships between implicit power motivation (n Power), a preference for having impact and dominance over others, and both salivary estradiol and testosterone in women. 49 participants completed the Picture Story Exercise, a measure of n Power. During a laboratory contest, participants competed in pairs on a cognitive task and contest outcome (win vs. loss) was experimentally varied. Estradiol and testosterone levels were determined in saliva samples collected at baseline and several times post-contest, including 1 day post-contest. n Power was positively associated with basal estradiol concentrations. The positive correlation between n Power and basal estradiol was stronger in single women, women not taking oral contraceptives, or in women with low-CV estradiol samples than in the overall sample of women. Women's estradiol responses to a dominance contest were influenced by the interaction of n Power and contest outcome: estradiol increased in power-motivated winners but decreased in power-motivated losers. For power-motivated winners, elevated levels of estradiol were still present the day after the contest. Lastly, n Power and estradiol did not correlate with self-reported dominance and correlated negatively with self-reported aggression. Self-reported dominance and aggression did not predict estradiol changes as a function of contest outcome. Overall, n Power did not predict basal testosterone levels or testosterone changes as a function of dominance contest outcome.     

Effects of affiliation and power motivation arousal on salivary progesterone and testosterone

Following up on earlier research suggesting a link between implicit affiliation motivation and progesterone (P) and implicit power motivation and testosterone [T; Schultheiss, O.C., Dargel, A., Rohde, W., 2003. Implicit motives and gonadal steroid hormones: Effects of menstrual cycle phase, oral contraceptive use, and relationship status. Horm. Behav. 43, 293-301.], we tested whether arousal of affiliation motivation increases P levels and whether arousal of power motivation increases T levels. Sixty subjects were randomly assigned to watch 30 min of either Bridges of Madison County (affiliation arousal) or The Godfather II (power arousal), or a documentary about the Amazon (control condition). Levels of P and T were assessed in saliva samples taken before (T1), immediately after (T2), and 45 min after the movie (T3). The efficacy of experimental conditions to differentially arouse motives was verified by assessment of changes in affiliation and power motive imagery expressed in imaginative stories written before and after the movie. After the movie, salivary P levels (T2 and T3) in the affiliation-arousal group were significantly higher than in the control group and marginally higher than in the power-arousal group. Subjects' postmovie T responses (T3) depended on premovie T levels: in men, higher premovie T levels predicted a greater likelihood of postmovie T increases in the Power Arousal condition but not in the other conditions, whereas in women, higher premovie T levels tended to be associated with postmovie T decreases in the Power Arousal condition but not in the other conditions. These findings suggest that aroused affiliation motivation has a specific stimulatory effect on P, whereas aroused power motivation has a specific stimulatory effect on T in men, but not in women, with high baseline T levels.     

Comparison of clear and narrow outcomes on testosterone levels in social competition

A contribution to a special issue on Hormones and Human Competition.Social competition is associated with marked emotional, behavioral and hormonal responses, including changes in testosterone levels. The strength and direction of these responses is often modulated by levels of other hormones (e.g. cortisol) and depends on psychological factors – classically, the objective outcome of a competition (win vs. loss) but also, hypothetically, the closeness of that outcome (e.g. decisive victory vs. close victory). We manipulated these two aspects of a social contest among male participants (N = 166), to investigate how testosterone and affect fluctuated as a function of clear vs. narrow wins and clear vs. narrow losses. We found that losing a competition by a small margin (a narrow loss) was experienced as more pleasant than a clear loss. Among individuals with higher levels of basal cortisol, winning the competition by a narrow margin was associated with a decrease in testosterone levels. These findings are discussed within the framework of the status instability hypothesis and the growing literature on how situational and physiological factors modulate testosterone reactivity to social contests.     

Winning agonistic encounters increases testosterone and androgen receptor expression in Syrian hamsters

Winning aggressive disputes is one of several experiences that can alter responses to future stressful events. We have previously tested dominant and subordinate male Syrian hamsters in a conditioned defeat model and found that dominant individuals show less change in behavior following social defeat stress compared to subordinates and controls, indicating a reduced conditioned defeat response. Resistance to the effects of social defeat in dominants is experience-dependent and requires the maintenance of dominance relationships for 14 days. For this study we investigated whether winning aggressive interactions increases plasma testosterone and whether repeatedly winning increases androgen receptor expression. First, male hamsters were paired in daily 10-min aggressive encounters and blood samples were collected immediately before and 15 min and 30 min after the formation of dominance relationships. Dominants showed an increase in plasma testosterone at 15 min post-interaction compared to their pre-interaction baseline, whereas subordinates and controls showed no change in plasma testosterone. Secondly, we investigated whether 14 days of dominant social status increased androgen or estrogen alpha-receptor immunoreactivity in brain regions that regulate the conditioned defeat response. Dominants showed more androgen, but not estrogen alpha, receptor immuno-positive cells in the dorsal medial amygdala (dMeA) and ventral lateral septum (vLS) compared to subordinates and controls. Finally, we showed that one day of dominant social status was insufficient to increase androgen receptor immunoreactivity compared to subordinates. These results suggest that elevated testosterone signaling at androgen receptors in the dMeA and vLS might contribute to the reduced conditioned defeat response exhibited by dominant hamsters.     

Rats Benefit from Winner and Loser Effects

Prior fighting experience of opponents can influence the outcome of conflicts. After a victory, animals are more likely to win subsequent contests, whereas after a defeat animals are more likely to lose, regardless of the identity of opponents. The underlying mechanisms and the adaptive significance of these winner and loser effects are as yet unknown. Here, we tested experimentally whether agonistic behavior of male wild‐type Norway rats is influenced by social experience, and we investigated whether this might reduce fighting costs (duration of contest, risk of injury) in subsequent encounters. Rats were randomly assigned to receive either a losing or a winning experience and subsequently tested with unfamiliar, naïve opponents. We found that most rats with a winning experience won the subsequent encounter, and all rats with a losing experience lost the next contest. Previous winners attacked more rapidly in the subsequent encounter and reduced their aggressive behavior sooner; the contests were decided more quickly, which saved time and behavioral effort to the winner. Previous losers received less aggression in the next encounter, despite emitting fewer submissive ultrasonic calls than in the preceding contest, thereby reducing the risk of being injured by the opponent. Thus, anonymous social experience influenced rats’ subsequent behavior toward size‐matched, naïve, unknown social partners. Furthermore, apparently, they benefit from showing winner and loser effects in intraspecific contests by saving time, energy, and risk.     

Previous experience and contest outcome: winner effects persist in absence of evident loser effects in a parasitoid wasp

Abstract The experience of a previous conflict can affect animals' performance during a later contest: a victory usually increases and a defeat usually decreases the probability of winning a subsequent conflict. These winner and loser effects could result from a reassessment by contestants of their perceived fighting abilities. Game-theoretic models based on this assumption predict that a loser effect can exist alone or in the presence of a winner effect, but a winner effect cannot persist alone, at least when contestants are young and without experience of contest. Moreover, when both effects coexist, the loser effect is expected to be of a greater magnitude and last longer than the winner effect. To date, these predictions have been supported by empirical evidence. Here we show for the first time that a winner effect can exist in the absence of any evident loser effect in a parasitoid wasp, Eupelmus vuilleti, when fighting for hosts. This finding consequently raises questions about the possible mechanisms involved and challenges the main assumption of previous theoretical models. We suggest an alternative explanation for the evolution of only winner effects that is based on the modification of contestants' subjective value of the resource rather than on a reestimation of their fighting abilities.     

Aggressive behaviour in rats: Effects of winning or losing on subsequent aggressive interactions

CPB-WE rats (WEzobs) tested for aggression against Tryon Maze Dull rats (S3s) were highly consistently defeated. In contrast, when tested against Wistars, these WEzobs become dominant. On the basis of these findings an experimental procedure was used in which the changes in agonistic responses as the result of experience of victory or defeat could be established. In addition, the effect of winning or losing was studied in subsequent encounters of winners and defeated WEzobs. The result of this experiment clearly indicate that a significant and relatively permanent behavioural inhibition develops in the defeated WEzobs which show less social initiative and aggression than the winners. The behavioural inhibition which is also seen in the spatial orientation of the animals within the test arena was still present after a 14 day interval. Significant loss of body weight was found in the losing animals.     

The ‘home advantage’ is necessary for a full winner effect and changes in post-encounter testosterone

Winning aggressive contests can both enhance future winning ability and change post-encounter hormones; however, it remains unclear if the context of a fight also influences such winner effects and hormone changes. We investigated this issue by using California mice (Peromyscus californicus) to test if the effect of residency status is necessary to improve future winning ability and alter post-encounter hormones. Male mice were subjected to an aggressive contest and their blood was collected 45 min after the fight. Upon contest initiation, focal mice had a ‘home advantage’ and three prior winning experiences, only one of these factors, or neither factor. Only individuals with a ‘home advantage’ and prior winning experience showed a full winner effect. Post-encounter changes in testosterone and progesterone resulted from an interaction between residency status and winning experience. These data indicate that in male California mice a ‘home advantage’ is necessary to produce the full winner effect and that residency status helps regulate inter-individual variation in the expression of post-encounter testosterone pulses and progesterone changes. Furthermore, these respective behavioral and physiological phenomena might be modulated in a context-specific manner, in part by the surrounding physical environment.     

Dominance,Politics, and Physiology: Voters' Testosterone Changes on the Night of the 2008 United States Presidential Election

Background

Political elections are dominance competitions. When men win a dominance competition, their testosterone levels rise or remain stable to resist a circadian decline; and when they lose, their testosterone levels fall. However, it is unknown whether this pattern of testosterone change extends beyond interpersonal competitions to the vicarious experience of winning or losing in the context of political elections. Women''s testosterone responses to dominance competition outcomes are understudied, and to date, a clear pattern of testosterone changes in response to winning and losing dominance competitions has not emerged.

Methodology/Principal Findings

The present study investigated voters'' testosterone responses to the outcome of the 2008 United States Presidential election. 183 participants provided multiple saliva samples before and after the winner was announced on Election Night. The results show that male Barack Obama voters (winners) had stable post-outcome testosterone levels, whereas testosterone levels dropped in male John McCain and Robert Barr voters (losers). There were no significant effects in female voters.

Conclusions/Significance

The findings indicate that male voters exhibit biological responses to the realignment of a country''s dominance hierarchy as if they participated in an interpersonal dominance contest.     

Interspecies hormonal interactions between man and the domestic dog (Canis familiaris)

To date, hormonal influence in interspecies interaction has not been examined. In a study of a dog agility competition among human/dog teams, men's pre-competition basal testosterone (T) levels were positively related to changes in dogs' cortisol levels from pre- to post-competition, but only among losing teams. Furthermore, pre-competition basal T in men on losing teams predicted more than half of the variance in dogs' cortisol change. This relationship was mediated through men's punitive and affiliative behaviors towards their dogs immediately after competition. Men's T change was also a significant predictor of dogs' change in cortisol such that men who experienced greater decreases in T after a loss were associated with dogs that experienced greater increases in cortisol. In winning teams, men's pre-competition T and T changes were unrelated to dogs' cortisol changes. These results are discussed in light of T as a proxy for dominance motivation as well as T's relation to stress across the species boundary.     

Implicit motives and gonadal steroid hormones: effects of menstrual cycle phase,oral contraceptive use,and relationship status

Implicit motives for power and affiliation, salivary levels of testosterone, estradiol, and progesterone, and relationship status were measured in 18 normally cycling (NC) women, 18 women using oral contraceptives (OC), and 18 men at three assessments, corresponding to the menstrual, midcycle, and premenstrual phases of women's menstrual cycle. NC and OC women had elevated levels of affiliation motivation and decreased levels of power motivation at midcycle. Power motive changes were particularly pronounced in NC women across cycle phases. OC women and participants not engaged in an intimate relationship had significantly heightened levels of affiliation motivation, averaged across all cycle phases. Testosterone and power motivation, both averaged across all cycle phases, were positively correlated in men and in single women, but not in women engaged in an intimate relationship. Averaged levels of estradiol and power motivation were positively correlated in engaged women, but not in single women or men. Averaged levels of progesterone and affiliation motivation were negatively correlated in men, and there was evidence for a positive association between luteal affiliation motivation and periovulatory and luteal progesterone in NC women. This study therefore provides evidence that implicit motivational states fluctuate across the menstrual cycle, that the power motive is associated with testosterone and, in women, with estradiol, and that the affiliation motive and progesterone are associated in different ways in men and NC women.     

Effects of affiliation arousal (hope of closeness) and affiliation stress (fear of rejection) on progesterone and cortisol

Our prior research has suggested a connection between progesterone (PROG) and implicit affiliation motivation, the non-conscious drive for positive social contact. In particular, experimental arousal of affiliation motivation led to relative PROG increase in women and men [Schultheiss, O.C., Wirth, M.M., Stanton, S.J., 2004. Effects of affiliation and power motivation arousal on salivary progesterone and testosterone. Horm. Behav. 46(5), 592-599]. The present study aimed to (1) replicate this effect, (2) simultaneously assess cortisol (CORT) levels in this paradigm in order to rule out non-specific adrenal effects induced by affiliation arousal, and (3) examine effects on PROG and CORT of approach (hope for closeness, HOC) versus avoidance (fear of rejection, FOR) affiliation arousal. These motivational states were experimentally aroused in participants using film segments containing approach- or avoidance-oriented affiliation-related themes; a neutral film segment was used as a control condition. The film segments affected participants' implicit affiliation motivation and self-reported mood, demonstrating effectiveness of the manipulation. In the FOR condition, participants' CORT and PROG were increased post-film, consistent with the idea that fear of rejection is stressful. We did not replicate our prior finding of PROG increase following the HOC manipulation. However, relationships between PROG and implicit affiliation motivation were apparent across conditions. In particular, PROG co-varied positively with affiliation motivation, and baseline affiliation motivation positively predicted PROG increase in the FOR condition. As prior research implicates PROG in down-regulation of stress, we speculate that PROG release during stress may encourage affiliation for stress reduction purposes.     

Testosterone and cortisol release among Spanish soccer fans watching the 2010 World Cup final

This field study investigated the release of testosterone and cortisol of a vicarious winning experience in Spanish fans watching the finals between Spain and the Netherlands in the 2010 FIFA World Cup Soccer. Spanish fans (n = 50) watched the match with friends or family in a public place or at home and also participated in a control condition. Consistent with hypotheses, results revealed that testosterone and cortisol levels were higher when watching the match than on a control day. However, neither testosterone nor cortisol levels increased after the victory of the Spanish team. Moreover, the increase in testosterone secretion was not related to participants' sex, age or soccer fandom, but the increase in total cortisol secretion during the match was higher among men than among women and among fans that were younger. Also, increases in cortisol secretion were greater to the degree that people were a stronger fan of soccer. Level of fandom further appeared to account for the sex effect, but not for the age effect. Generally, the testosterone data from this study are in line with the challenge hypothesis, as testosterone levels of watchers increased to prepare their organism to defend or enhance their social status. The cortisol data from this study are in line with social self-preservation theory, as higher cortisol secretion among young and greater soccer fans suggests that especially they perceived that a negative outcome of the match would threaten their own social esteem.     

The effects of competition and implicit power motive on men's testosterone,emotion recognition,and aggression

A contribution to a special issue on Hormones and Human Competition.We investigated the effects of competition on men's testosterone levels and assessed whether androgen reactivity was associated with subsequent emotion recognition and reactive and proactive aggression. We also explored whether personalized power (p Power) moderated these relationships. In Study 1, 84 males competed on a number tracing task and interpreted emotions from facial expressions. In Study 2, 72 males competed on the same task and were assessed on proactive and reactive aggression. In both studies, contrary to the biosocial model of status (Mazur, 1985), winners' testosterone levels decreased significantly while losers' levels increased, albeit not significantly. Personalized power moderated the effect of competition outcome on testosterone change in both studies. Using the aggregate sample, we found that the effect of decreased testosterone levels among winners (compared to losers) was significant for individuals low in p Power but not for those with medium or high p Power. Testosterone change was positively related to emotion recognition, but unrelated to either aggression subtype. The testosterone-mediated relationship between winning and losing and emotion recognition was moderated by p Power. In addition, p Power moderated the direct (i.e., non-testosterone mediated) path between competition outcome and emotion recognition and both types of aggression: high p-Power winners were more accurate at deciphering others' emotions than high p-Power losers. Finally, among high p-Power men, winners aggressed more proactively than losers, whereas losers aggressed more reactively than winners. Collectively, these studies highlight the importance of implicit power motivation in modulating hormonal, cognitive, and behavioral outcomes arising from human competition.     

Public speaking in front of an unreceptive audience increases implicit power motivation and its endocrine arousal signature

The present study explored the motivational characteristics of the Trier Social Stress Test (TSST; Kirschbaum, Pirke, & Hellhammer, 1993). Seventy-two participants either completed the public-speaking component of the TSST or, as a control condition, the friendly TSST (Wiemers, Schoofs, & Wolf, 2013) and wrote picture stories both before and after treatment. Stories were coded for motivational imagery related to power, achievement, and affiliation as well as for activity inhibition, a marker of functional brain lateralization during stress. The TSST had a specific arousing effect on power motivation, but not on other motivational needs, on activity inhibition, or on story length. TSST-elicited increases in power imagery, but not in achievement or affiliation imagery, were associated with a relatively greater salivary alpha-amylase response and with a relatively lesser salivary cortisol response. These findings suggest that the TSST specifically induces power-related stress.     

Women's intercollegiate volleyball and tennis: Effects of warm-up, competition, and practice on saliva levels of cortisol and testosterone

In virtually all sports, participants “warm-up” prior to formal competition. Women athletes from a highly ranked varsity college volleyball team and, in a second study, a highly ranked varsity college tennis team gave saliva samples before warm-up, at mid-warm-up (volleyball) or after warm-up (tennis), and immediately after intercollegiate competition. For volleyball and tennis, warm-up was associated with a substantial elevation in saliva levels of testosterone which was carried over through the period of actual competition. Cortisol levels were relatively unchanged during warm-up, but typically rose during competition. Thus, as women prepare for athletic competition by warming up, testosterone levels rise in apparent anticipation of the coming contest and then remain high through the period of play. In volleyball and tennis, after-practice testosterone level was significantly higher than before-practice level, and practice session increases in testosterone (but not cortisol) were positively correlated with increases in testosterone during intercollegiate competition. When practice and competitive play share as yet undetermined key elements, individual differences in this endocrine response to “competition” appear stable across practice and intercollegiate competition.     

Reciprocity between endocrine state and contest behavior in the killifish, Kryptolebias marmoratus

Given the dramatic behavioral effects of winning and losing contests, and pronounced changes in stress and sex steroid hormones post-fight, it is reasonable to suppose that these hormones also dictate future behavior. We sampled water-borne cortisol, testosterone (T), and 11-ketotestosterone (KT) before and after contests in the mangrove killifish, Kryptolebias marmoratus, to determine how endogenous steroid hormone levels might predict and respond to contest dynamics or success. Pre-fight cortisol related negatively, and pre-fight T related positively to contest initiation and winning, particularly in the smaller opponent. In the pairs where a larger fish won the contest, winners with higher pre-fight T and lower pre-fight cortisol delivered more attacks to the losers. Contest duration and escalation influenced post-fight hormone concentrations primarily in losers. Escalation significantly increased post-fight cortisol, T, and KT for losers but not for winners. However, winners that attacked losers at higher rates had higher levels of post-fight cortisol. Losers also demonstrate the most consistent post-fight hormone responses, particularly to contest escalation and duration. Despite the bidirectional relationship between hormones and contest behavior, we found no overall mean differences in pre- or post-fight cortisol, T, or KT between eventual winners and losers. Thus, it is evident that the categorical states of winner and loser cannot alone reveal the complex, reciprocal associations between endocrine systems and social behavior.