The Family Biorhythm: Contributions of the HPA and HPG Axes to Neuroendocrine Attunement.

Objective: The vast majority of research on biobehavioral influences on development has focused on mothers and infants, whereas research on paternal biobehavioral influences remains sparse. This study aims to increase understanding of paternal influences on the biobehavioral dynamics of the family unit, using a multi-system approach. Methods: Participants consisted of 32 predominantly high-risk families recruited during pregnancy who completed monthly questionnaires and in-home visits when infants were 4, 12, and 18 months of age. In-home visits included semi-structured interaction tasks and saliva samples for cortisol and progesterone assays. Results: Mothers and infants, but not fathers and infants, showed adrenocortical attunement, with the strongest attunement at 18 months. Second, mothers' couple satisfaction did not significantly impact infants' cortisol levels or mother-infant cortisol attunement, but mothers' progesterone moderated the relationship between couple satisfaction and infant cortisol levels such that mothers with low couple satisfaction, but high progesterone, had infants with lower cortisol levels. Finally, mothers' and fathers' progesterone levels were attuned across the time points. Conclusions: This is some of the first evidence of the establishment of the family biorhythm and suggests that fathers play an indirect role in facilitating mother-infant adrenocortical attunement. Supplementary Information: The online version contains supplementary material available at 10.1007/s40750-023-00215-0.

Women's Mating Strategies and Mate Value Are Associated with Viewing Time to Facial Masculinity.

Sexual selection has shaped women's preferences for ideal physical features in men that signal good health. Facial masculinity is often used as a proxy in signaling health, viability, and disease resistance, and it is thought to be attractive because it advertises heritable benefits. Preferences for facial masculinity are also associated with individual differences in one's sociosexuality and mate value, where women oriented toward a short-term mating orientation and are of high mate value may prefer men with masculine features. The current study examined women's sociosexuality and mate value (i.e., self-rating of overall desirability) in rating attractiveness and visual attention to facial masculinity in men's faces using an eye-tracking task. Overall, women (N = 72) did not show any significant preferences for men with masculinized over feminized faces. However, women who scored high on sociosexuality (i.e., unrestricted sociosexuality) and mate value demonstrated increased visual attention and looking frequency to masculinized over feminized faces. The study highlights the unique role of cognitive mechanisms in visually assessing a potential mate and how individual differences in short-term mating strategies and mate value may moderate those preferences. These findings underscore the importance of examining individual differences in mate preferences research.

An Eye Tracking Study Examining the Role of Mating Strategies, Perceived Vulnerability to Disease, and Disgust in Attention to Pathogenic Cues.

Disgust is an emotion that regulates disease avoidance and reduces the likelihood of pathogenic infections. Existing research suggests a bidirectional relationship between disgust and mating, where disgust inhibits sexual behavior and sexual behavior inhibits disgust. In the current study, we investigated the role of individual differences and mating motivations on visual attention to pathogenic cues. Participants (N = 103) were randomly assigned to a mating prime or control condition, and they were asked to view images of pathogenic cues (i.e., rotten food, exposed cuts, bodily fluids) paired with their non-pathogenic counterparts. The findings showed no effect of mating prime on visual attention to pathogenic stimuli; however, dispositional mating strategies (SOI-R) were associated with attention to pathogenic stimuli. Individuals with unrestricted sociosexual orientations viewed pathogenic stimuli longer. The findings demonstrate that dispositional mating orientation is associated with greater attention to disgusting images, a link between pathogens and mating orientation that warrants further exploration.

Ecological influences and visual attention to infant phenotypes.

In humans, the allocation of resources, such as parental care and attention, is vital to offspring survival. Life history strategies are influenced by cues in the environment, particularly those that signal the availability of resources. What has yet to be determined is how individuals allocate resources to infants as a function of perceived ecological harshness and life history strategy. In the current research we hypothesized that perceived ecology would influence infant ratings (Study 1), and that visual attention to infant phenotypes would be associated with life history strategies (Study 2). Study 1 investigated the effect of ecological conditions (control vs. harsh) on preferences to infant phenotypes (i.e., underweight, average weight, overweight). Participants (N = 246) were less likely to rate infants favorably under a harsh ecological condition. Study 2 investigated visual perception in processing infant images. Using an eye-tracking task, participants (N = 239) viewed images of infants while their eye movements were recorded. Participants displayed an early attentional bias (i.e., first fixation duration) to the head of the infant and focused most of their visual attention to the torso of infants (i.e., total visit duration). The results of the both studies indicate that ecological factors play an important role in rating infants, and data from eye-tracking demonstrates that phenotypes influence the amount of attention given to infants.

The role of hormones in attraction and visual attention to facial masculinity.

The current study investigated the ovulatory shift hypothesis, which suggests that women prefer more masculine traits when estradiol is high, and progesterone is low (E/P ratio). The current study used an eye tracking paradigm to measure women's visual attention to facial masculinity across the menstrual cycle. Estradiol (E) and progesterone (P) were collected to determine if salivary biomarkers were associated with visual attention to masculine faces in a short- and long-term mating context. Women (N = 81) provided saliva samples at three time points throughout their menstrual cycle and were asked to rate and view men's faces that had been manipulated to appear feminine and masculine. Overall, masculine faces were viewed longer compared to feminine faces and this was moderated by mating context, where women viewed masculine faces longer for a long-term relationship. There was not any evidence suggesting that E/P ratio was associated with preferences for facial masculinity, but there was evidence to suggest that hormones were associated with visual attention to men in general. In line with sexual strategies theory, there was evidence to suggest that mating context and facial masculinity are important in mate choice; however, there was no evidence to suggest that women's mate choice was associated with shifts across the menstrual cycle.

The Interacting Effects of Height and Shoulder-to-Hip Ratio on Perceptions of Attractiveness, Masculinity, and Fighting Ability: Experimental Design and Ecological Validity Considerations.

Previous research has shown that men's height and upper body size are both associated with the perception of attractiveness, because they might be cues to men's genetic fitness, fighting ability, and resource holding power. However, the combined effects of men's height and upper body size have not been explored. In this research, across four studies (N = 659 heterosexual women), we systematically explored the perception of men's muscular upper body at different heights on perceptions of attractiveness, masculinity, and fighting ability. Women rated male stimuli with heights ranging from 160 cm (5'3″) to 190 cm (6'3″) and three values of shoulder-to-hip ratio (SHR). In general, results showed that women considered taller men and men with larger SHR as more attractive, masculine, and better in fighting ability. However, a robust interaction between height and SHR was dependent on participants being exposed to variation on both variables and the ecological validity of the stimuli (silhouettes vs. more realistic rendered figures).

The Modification of Offspring Stress-Related Behavior and the Expression of Drd1, Drd2, and Nr3c1 by a Western-Pattern Diet in Mus Musculus.

The impact of early developmental experience on neurobiological pathways that may contribute to the association between diet and behavior have not yet been elucidated. The focus of the current study was to determine whether the impact of prenatal stress (PS) could be mitigated by a diet that stimulates the same neuroendocrine systems influenced by early stress, using a mouse model. Behavioral and genetic approaches were used to assess how a Western-pattern diet (WPD) interacts with PS and sex to impact the expression of anxiety-like behavior in an open-field arena, as well as the expression of the glucocorticoid receptor in the hippocampus, D1 dopamine receptors in the nucleus accumbens, and D2 dopamine receptors in the ventral tegmental area. Overall, the results demonstrated that a prenatal WPD mitigates the effects of maternal stress in dams and offspring. These results help to elucidate the relationship between pre- and post-natal nutrition, gene expression, and behaviors that lead to long-term health effects.

Women's Preferences for Strong Men Under Perceived Harsh Versus Safe Ecological Conditions.

Ecological conditions provide information about available resources for one's environment. In humans, this has been shown to influence reproductive behavior, as individuals may engage in trade-offs between partner quality and investment. For instance, many women may trade-off preferences for men with physical features indicative of social dominance and health over physical features indicative of commitment and investment. The current study explored women's preferences for formidable men under safe vs. harsh ecological conditions. Across three studies, U.S. university women (N = 1,098) were randomly assigned to a perceived harsh or safe ecological condition. They were asked to rate the attractiveness of men's body types (i.e., muscular vs. less muscular). Findings revealed that in general, women rated stronger men as more attractive than weaker men irrespective of the ecological condition. Evidence for preference as a function of ecology appeared only when a two-alternative forced-choice task was used (Study 3), but not in rating tasks (Studies 1 and 2). Study 3 showed that women had a relatively stronger preference for stronger men for short-term relationships in a resource scarce ecological condition. This research provides some evidence that perceived ecological conditions can drive women's preferences for men with enhanced secondary sex characteristics as a function of mating context. These findings are consistent with previous research indicating the importance of physical characteristics in men's attractiveness, and it adds to the existing literature on ecological factors and mating preferences.

The endocrinology of female friendships: Cortisol and progesterone attunement after separation.

Friendships constitute important relationships, and often function to reduce stress, but have been under-studied. In mother-child dyads, infants coordinate their stress response with their caregivers without experiencing the stressor themselves. The current study used a modified version of the Trier Social Stress Test to examine whether i) friends are physiologically attuned (i.e., cortisol and progesterone); ii) attunement differs as a function of social acceptance or rejection external to the dyad; and, iii) friends can 'catch' a stress response only through non-verbal cues. Friends showed both cortisol and progesterone attunement at the beginning of the study. Friends showed cortisol attunement across time and conditions. Friends' progesterone levels were significantly, but negatively associated across time and conditions. They did not, however, show a stress contagion as a result of one friend experiencing stress. These findings suggest that cortisol and progesterone play different roles in the attunement of stress and subsequent affiliation.

Effects of Women's Short-Term Mating Orientation and Self-Perceived Attractiveness in Rating and Viewing Men's Waist to Chest Ratios.

Women's mating strategies are dependent on multiple factors, such as identifying which men advertise physical features indicating high genetic quality, as well as identifying which men are willing to invest in offspring. Research has suggested that women pursuing short-term mating prioritize physical attraction to facilitate the acquisition of good genes. Although it is known that physical characteristics are important in mate choice, research investigating the saliency of physical features in assessing male fitness has not been readily explored. The current study used an eye-tracking paradigm to investigate the role of short-term mating in women and their attraction and visual attention to men's waist to chest ratios (WCRs). Women's short-term mating orientation (N = 130) was associated with attraction to men with low WCRs; however, their visual attention was not influenced by their mating strategy. Interestingly, women who perceived themselves as attractive rated men with low WCRs as more attractive and allocated attentional resources to physical features important in mate choice, such as the head and midriff region. The findings from this study lend some support to sexual strategies theory (Buss & Schmitt, 1993) and strategic pluralism (Gangestad & Simpson, 2000), and they suggest that mate preferences may be calibrated as a function of one's mate value.

An Eye Tracking Examination of Men's Attractiveness by Conceptive Risk Women.

Previous research has indicated that women prefer men who exhibit an android physical appearance where fat distribution is deposited on the upper body (i.e., shoulders and arms) and abdomen. This ideal physical shape has been associated with perceived dominance, health, and immunocompetence. Although research has investigated attractability of men with these ideal characteristics, research on how women visually perceive these characteristics is limited. The current study investigated visual perception and attraction toward men in Hispanic women of Mexican American descent. Women exposed to a front-posed image, where the waist-to-chest ratio (WCR) and hair distribution were manipulated, rated men's body image associated with upper body strength (low WCR 0.7) as more attractive. Additionally, conceptive risk did not play a strong role in attractiveness and visual attention. Hair distribution did not contribute to increased ratings of attraction but did contribute to visual attraction when measuring total time where men with both facial and body hair were viewed longer. These findings suggest that physical characteristics in men exhibiting upper body strength and dominance are strong predictors of visual attraction.