Preprint "Effects of male testosterone and its interaction with cortisol on self- and observer-rated personality states in a competitive mating context"

Increases in human male testosterone (T) levels have been found after intrasexual competitions and exposure to females, facilitating competitive and courtship behaviours. This suggests that T reactivity should affect relevant personality state changes that are also observable to others. How exactly T reactivity, also under potential buffering effects of Cortisol (C), relates to personality state changes is unclear. In a preregistered study, we aimed at inducing T increases in young men (N=165) through dyadic intrasexual competitions while exposed to a female experimenter. We investigated self-reported and video-based observer-rated personality state changes, as captured by the Interpersonal Circumplex and social impressions, in relation to hormonal levels. Results revealed increases in self-reported competitiveness, as well as observer-rated dominance and self-assurance, relative to a control group and moderated by T reactivity and partly by TxC interactions. Thus, male T reactivity in a competitive mating context increased competitiveness/dominance, but did not decrease nurturance. This provides further insights into how hormonal and personality responses to challenges are intertwined in men, and partly supports a role of T in mediating a life history trade-off between mating/competing and parenting, as well as signalling dominance to rivals and potential mates.

A Comparison of Characteristics of Improved Total Contact Insoles

The purpose of this study is to investigate the effects of two kinds of total contact insoles (TCI). Traditional TCI reflects the shape of foot, while deformed total contact insole(DTCI) was established basing on the shape of footprints on clay prototypes. A female experimenter was asked to exert different loadings on clay prototypes to make footprints. Shapes of the footprints have been recorded by a reverse engineering method. Force distribution results in given preconditions were reflected and recorded for quantified comparison. shapes of two total contact insoles were rebuilt under different loadings. Having deformation of different magnitude over each area as a reference, effect and possibility of further improvement have been explored. Our findings showed that insoles based on larger deformation can be utilized to redistribute peak pressure effectively under normal loading. The results indicates that DTCI in this study can be used as a more important tool in adjusting functions or comfort ratings of shoes.

Effects of a Smile on Mood and Helping Behavior

In this study 480 native Dutch passers-by (240 men and 240 women) were approached with a request to participate in an investigation. The request was made by either a female or male experimenter wearing either a smile or a neutral expression. Results showed that a smiling experimenter elicited a smile from participants more often than when a neutral expression was displayed. Furthermore, there was a distinct correlation between a participant's smiling and his/her willingness to help, and a smile from a male experimenter was more likely to elicit helpfulness than from a female experimenter. Participants who agreed to help also answered a few written questions. These results showed that participants who received a smile from an experimenter were in a more positive mood than those who were approached by an experimenter wearing a neutral expression. It was also found that women smiled more often than men.

EFFECT OF EXPERIMENTER ATTIRE AND SEX ON PARTICIPANT PRODUCTIVITY

The experimental environment is complex and many subtle variables can influence the research findings. We investigated whether the sex of experimenter, the formality of experimenter attire, and the sex of participant affected respondents' productivity when asked to describe a business executive. The results revealed a significant interaction between experimenter sex and attire. Participants generated more terms and took longer to describe the business executive when the female experimenter was dressed casually and when the male experimenter was dressed professionally.

Smiling of Male and Female Infants to Mother vs Stranger at 2 and 3 Months of Age

The study examined the recognition-assimilation hypothesis of infant smiling. The subjects were 64 (32 female and 32 male) full-term infants who were visited at their home at ages two and three months by a female experimenter. The mother and then the female stranger each interacted face-to-face with the infants for 3 min. All interactions were videotaped and later independent coders recorded the cumulative amount of time that the infants smiled to the mother and to the stranger. The results show that, whereas female infants smiled significantly more to the stranger than to the mother at both ages, male infants smiled more to the mother only at two months. At three months, male infants smiled about the same length of time to both mother and stranger. The results support the recognition-assimilation hypothesis and suggest that females develop faster socially.

The Effects of Self-Presentation on Perceived Exertion

This study was designed to examine the audience-pleasing and self-constructional aspects of self-presentation on perceived exertion. Subjects performed two 18-min sessions on a cycle ergometer at light, moderate, and heavy workloads, during which perceived exertion and heart rate were collected. Each subject participated in a male and female experimenter condition. Males reported significantly lower perceived exertion in the female experimenter condition at the heavy load, compared to the same load in the male experimenter condition. There were no other significant differences for males or females at any of the workloads in either condition. Responses on the Self-Monitoring Inventory were used to assign subjects to either a high or low self-construction group. Results indicated that high self-constructors recorded significantly lower perceived exertion, compared to low self-constructors, at the low and moderate workloads.

Maternal Education and Cognitive Processing at Three Months as Shown by the Infants' Vocal Response to Mother vs. Stranger

The main objective of this study was to examine whether infants of high education mothers show higher cognitive processing than infants of lower education mothers at age three months. Cognitive processing was assessed by the infants' differential vocal responsiveness (DVR) to mother vs. stranger, a behaviour that has been shown to relate to later intelligence. The subjects were 14 infants from highly educated mothers and 21 infants from less educated mothers. When the infants were 3 months old a female experimenter visited them in their home where the mother and the experimenterstranger each talked to the baby for three minutes. The infants' vocalisations were recorded and subsequently an independent coder assigned a DVR score to each infant by subtracting its non-distress vocal output in response to the stranger from its vocal output in response to the mother. Infants of higher education mothers were found to have significantly higher DVR scores than infants of less educated mothers.

Evaluating Competence of Women and Men: Effects of Experimenter Gender and Group Gender Composition

College students (78 females, 79 males) were placed in all-female, all-male, or mixed-gender groups. In the presence of a male or female experimenter, subjects evaluated an article written by a female or male job applicant. Subjects in mixed-gender groups generally evaluated the female applicant more favorably in the presence of the female experimenter than the male experimenter. Subjects in mixed-gender groups also rated the female applicant more favorably than the male applicant in the presence of the female experimenter. Male subjects generally were more influenced than were females by the experimenter's gender, tending to give higher ratings to the applicant of the same gender as the experimenter.

Increasing Treatment Efficiency through Effective Intake Interviews

Male patients in an alcohol detoxification unit were measured to determine whether the method of acquiring symptoms and sex of the experimenter affected the number and severity of symptoms elicited. A male or female experimenter administered a checklist of symptoms and the Marlowe-Crowne Social Desirability Scale to 100 patients. A MANCOVA indicated there was a significant difference between method 1 (nondirective) and method 2 (leading). Subsequent univariate analyses yielded significant differences between the methods and both dependent measures, number of symptoms acquired and their severity. The leading method was more effective for acquiring symptoms, and more moderate symptoms, which were typically overlooked by the patients during the nondirective phase, were obtained.