Women's hormone levels modulate the motivational salience of facial attractiveness and sexual dimorphism

Do women's natural hormonal fluctuations modulate prosociality? A within-subject analysis

Prosocial behavior is central to functional societies. While studies have shown that the administration of exogenous hormones modulates prosocial propensities, it remains unclear whether natural hormonal fluctuations track women's prosocial behavior. In this study, we investigated the relationships between women's natural salivary steroid hormone levels (estradiol, progesterone, and testosterone) and their prosociality in a variety of contexts, as measured by three behavioral tasks (Charitable Donation, Social Value Orientation, and Social Discounting tasks) and one self-reported questionnaire (the Prosocial Tendencies Measure). Participants completed five weekly laboratory tests to obtain within-subject hormonal fluctuation data and prosociality measurements. In a pre-registered analysis, we found little evidence supporting the hypotheses that women's prosociality tracked natural changes in salivary estradiol, progesterone, estradiol-to-progesterone ratio, or testosterone. Our results demonstrate the importance of performing within-subject analyses when examining the relationships between hormonal levels and social behavior.

Does testosterone predict women's preference for facial masculinity?

The influence of sex hormones on women’s mate preferences has been an intensively discussed topic for more than a decade. Yet the extent to which levels of sex hormones, and testosterone in particular, influence women’s mate preferences is unclear. Thus, the current study used multilevel modelling to investigate putative relationships between salivary testosterone and facial masculinity preferences in a sample of 68 women, while controlling for their age, partnership status, and sociosexuality. We found no significant associations between masculinity preferences and either individual differences or within-woman changes in testosterone. We did find however, that sociosexuality was positively correlated with masculinity preferences. Although it has previously been suggested that testosterone is related to women’s facial masculinity preference, our data do not support this proposal.

Sex and Physiological Cycles Affect the Automatic Perception of Attractive Opposite-Sex Faces: A Visual Mismatch Negativity Study

Facial attractiveness plays important roles in social interaction. Electrophysiological and neuroimaging studies found several brain areas to be differentially responsive to attractive relative to unattractive faces. However, little is known about the time course of the information processing, especially under the unattended condition. Based on a "cross-modal delayed response" paradigm, the present study aimed to explore the automatic mechanism of facial attractiveness processing of females with different physiological cycles and males, respectively, through recording the event-related potentials in response to (un)attractive opposite-sex faces by two experiments. The attractiveness-related visual mismatch negativity (attractiveness vMMN) in posterior scalp distribution was recorded in both the experiments, which indicated that attractive faces could be processed automatically. And high-attractive opposite-sex faces can elicit larger vMMN in males than females in menstrual period in Study 1, but similar as females in ovulatory period in Study 2. Furthermore, by comparison, the latency of attractiveness vMMN in females with the ovulatory period was the longest. These results indicated as follows: (1) Males were more sensitive to attractive female faces, (2) females in ovulatory period were also attracted by the attractive male faces, (3) the long vMMN latency in females during ovulatory period suggested a special reproductive motivation to avoid being tainted by genes, which takes priority over the breeding motivation.

Women's preferences for men's beards show no relation to their ovarian cycle phase and sex hormone levels

According to the ovulatory shift hypothesis, women's mate preferences for male morphology indicative of competitive ability, social dominance, and/or underlying health are strongest at the peri-ovulatory phase of the menstrual cycle. However, recent meta-analyses are divided on the robustness of such effects and the validity of the often-used indirect estimates of fertility and ovulation has been called into question in methodological studies. In the current study, we test whether women's preferences for men's beardedness, a cue of male sexual maturity, androgenic development and social dominance, are stronger at the peri-ovulatory phase of the menstrual cycle compared to during the early follicular or the luteal phase. We also tested whether levels of estradiol, progesterone, and the estradiol to progesterone ratio at each phase were associated with facial hair preferences. Fifty-two heterosexual women completed a two-alternative forced choice preference test for clean-shaven and bearded male faces during the follicular, peri-ovulatory (validated by the surge in luteinizing hormone or the drop in estradiol levels) and luteal phases. Participants also provided for one entire menstrual cycle daily saliva samples for subsequent assaying of estradiol and progesterone. Results showed an overall preference for bearded over clean-shaven faces at each phase of the menstrual cycle. However, preferences for facial hair were not significantly different over the phases of menstrual cycle and were not significantly associated with levels of reproductive hormones. We conclude that women's preferences for men's beardedness may not be related to changes in their likelihood of conception.

Effects of stress on women's preference for male facial masculinity and their endocrine correlates

Women's preferences for masculinity in men's faces seem to vary across the menstrual cycle and are assumed to be strongest around ovulation. A number of hormones have been proposed to underlie these subtle cyclic shifts. Furthermore, mating preferences are context-dependent, and stress has been found to alter mate choice, both in animals and humans. Currently, the effects of stress on women's preference for masculinity remain unknown. To examine the hormonal basis and the impact of stress on facial masculinity preference, we tested for within-subject changes in 52 healthy young women who underwent the Trier Social Stress Test (TSST) and the placebo-TSST in randomized order in the late follicular and mid-luteal phases of their menstrual cycle. Menstrual cycle phase and hormone levels were confirmed using estradiol, testosterone, progesterone, and cortisol analyses from saliva. Results show that women were more likely to be attracted to masculine-faced men right before ovulation than in the mid-luteal phase. Estradiol modulated this masculinity preference with high estradiol levels being related to stronger masculinity preference. When stressed however, women experienced a decrease in male facial masculinity preference. In line with these findings, the higher the cortisol increase to stress, the less were masculine faces preferred to more feminine faces. Mate choice is a central component of reproduction. The present results provide information about the effects of stress and hormonal influences on mate preferences in women.

Expectations for future relationship satisfaction: Unique sources and critical implications for commitment

Contemporary perspectives on relationship commitment posit that intimates decide whether or not to maintain a relationship based on their commitment to that relationship, and that they base such commitment partially on their current satisfaction with that relationship. Nevertheless, given that ending a relationship requires knowing about both the current state of the relationship and the likely future state of the relationship, we propose that people base their commitment to a relationship more on their expected future satisfaction with the relationship than on their current satisfaction with that relationship. Six studies provided evidence for these ideas. Study 1 demonstrated that expected satisfaction is shaped by not only current satisfaction but also several unique indicators of the likelihood of future satisfaction, including anticipated life events, plans to improve the relationship, and individual differences. Then, using a combination of cross-sectional, experimental, and longitudinal methods, Studies 2 through 6 demonstrated that (a) expected satisfaction was a stronger predictor of relationship commitment, maintenance behaviors, and/or divorce than was current satisfaction and (b) expected satisfaction mediated the association between current satisfaction and these outcomes. These findings highlight not only the need to incorporate expected satisfaction into extent perspectives on commitment, but also the importance of expectations for decision-making processes more broadly. (PsycINFO Database Record

The Motivational Salience of Faces Is Related to Both Their Valence and Dominance

Both behavioral and neural measures of the motivational salience of faces are positively correlated with their physical attractiveness. Whether physical characteristics other than attractiveness contribute to the motivational salience of faces is not known, however. Research with male macaques recently showed that more dominant macaques’ faces hold greater motivational salience. Here we investigated whether dominance also contributes to the motivational salience of faces in human participants. Principal component analysis of third-party ratings of faces for multiple traits revealed two orthogonal components. The first component (“valence”) was highly correlated with rated trustworthiness and attractiveness. The second component (“dominance”) was highly correlated with rated dominance and aggressiveness. Importantly, both components were positively and independently related to the motivational salience of faces, as assessed from responses on a standard key-press task. These results show that at least two dissociable components underpin the motivational salience of faces in humans and present new evidence for similarities in how humans and non-human primates respond to facial cues of dominance.

A longitudinal analysis of women's salivary testosterone and intrasexual competitiveness

Research on within-subject changes in women's intrasexual competitiveness has generally focused on possible relationships between women's intrasexual competitiveness and estimates of their fertility. While this approach is useful for testing hypotheses about the adaptive function of changes in women's intrasexual competitiveness, it offers little insight into the proximate mechanisms through which such changes might occur. To investigate this issue, we carried out a longitudinal study of the hormonal correlates of changes in intrasexual competitiveness in a large sample of heterosexual women (N=136). Each woman provided saliva samples and completed an intrasexual competitiveness questionnaire in five weekly test sessions. Multilevel modeling of these data revealed a significant, positive within-subject effect of testosterone on intrasexual competitiveness, indicating that women reported greater intrasexual competitiveness when testosterone was high. By contrast, there were no significant effects of estradiol, progesterone, estradiol-to-progesterone ratio, or cortisol and no significant effects of any hormones on reported relationship jealousy. This is the first study to demonstrate correlated changes in measured testosterone levels and women's reported intrasexual competitiveness, implicating testosterone in the regulation of women's intrasexual competitiveness.

Lady in Red

Recent evidence supports the idea that women use red clothing as a courtship tactic, and results from one study further suggested that women were more likely to wear red on days of high fertility in their menstrual cycles. Subsequent studies provided mixed support for the cycle-phase effect, although all such studies relied on counting methods of cycle-phase estimation and used between-subjects designs. By comparison, in the study reported here, we employed frequent hormone sampling to more accurately assess ovulatory timing and used a within-subjects design. We found that women were more likely to wear red during the fertile window than on other cycle days. Furthermore, within-subjects fluctuations in the ratio of estradiol to progesterone statistically mediated the within-subjects shifts in red-clothing choices. Our results appear to represent the first direct demonstration of specific hormone measurements predicting observable changes in women’s courtship-related behaviors. We also demonstrate the advantages of hormonal determination of ovulatory timing for tests of cycle-phase shifts in psychology or behavior.

Facial coloration tracks changes in women's estradiol

Red facial coloration is an important social cue in many primate species, including humans. In such species, the vasodilatory effects of estradiol may cause red facial coloration to change systematically during females' ovarian cycle. Although increased red facial coloration during estrus has been observed in female mandrills (Mandrillus sphinx) and rhesus macaques (Macaca mulatta), evidence linking primate facial color changes directly to changes in measured estradiol is lacking. Addressing this issue, we used a longitudinal design to demonstrate that red facial coloration tracks within-subject changes in women's estradiol, but not within-subject changes in women's progesterone or estradiol-to-progesterone ratio. Moreover, the relationship between estradiol and facial redness was observed in two independent samples of women (N = 50 and N = 65). Our results suggest that changes in facial coloration may provide cues of women's fertility and present the first evidence for a direct link between estradiol and female facial redness in a primate species.

Sex difference in the relationship between salivary testosterone and inter-temporal choice

Humans often prefer a small immediate reward to large reward in the future. This myopic tendency in inter-temporal choice is termed delay discounting, and has been the focus of intensive research in the past decades. Recent studies indicate that the neural regions underlying delay discounting are influenced by the gonadal steroids. However, the specific relationship between the testosterone levels and delay discounting is unclear at this point, especially in females. The present study investigated the relationship between salivary testosterone concentrations and discounting rates in delay- and probability-discounting tasks with healthy males and females. The results revealed a positive correlation between testosterone concentrations and delay-discounting rates in females and a negative correlation in males. Testosterone concentrations were unrelated to probability-discounting rates. Although causal effects of testosterone cannot be certain in this correlational study, if testosterone directly influenced this behavior, observed sex differences in delay discounting may be evidence of a curvilinear effect of testosterone. Alternatively, the findings may reflect inverse pattern of responsiveness to testosterone between male and female neural systems, or basic sex-difference in the neural mechanism underlying delay-discounting independent of testosterone itself.