Evolutionary Neuroandrogenic Theory and Universal Gender Differences in Cognition and Behavior

Sex/gender differences in cognitive abilities

Sex/gender differences in cognitive sciences are riddled by conflicting perspectives. At the center of debates are clinical, social, and political perspectives. Front and center, evolutionary and biological perspectives have often focused on 'nature' arguments, while feminist and constructivist views have often focused on 'nurture arguments regarding cognitive sex differences. In the current narrative review, we provide a comprehensive overview regarding the origins and historical advancement of these debates while providing a summary of the results in the field of sexually polymorphic cognition. In so doing, we attempt to highlight the importance of using transdisciplinary perspectives which help bridge disciplines together to provide a refined understanding the specific factors that drive sex differences a gender diversity in cognitive abilities. To summarize, biological sex (e.g., birth-assigned sex, sex hormones), socio-cultural gender (gender identity, gender roles), and sexual orientation each uniquely shape the cognitive abilities reviewed. To date, however, few studies integrate these sex and gender factors together to better understand individual differences in cognitive functioning. This has potential benefits if a broader understanding of sex and gender factors are systematically measured when researching and treating numerous conditions where cognition is altered.

Effects of interpretation bias modification on hostile attribution bias and reactive cyber-aggression in Chinese adolescents: a randomized controlled trial

Highly aggressive individuals tend to interpret others' motives and intentions as hostile in both offline and online social situations. The current study examined whether hostile interpretation bias can be modified to influence cyber-aggression in Chinese middle school students using an interpretation bias modification program. Gender differences and the heterogeneity of cyber-aggression were also investigated since previous studies suggest that they play important roles in determining the intervention effect. One hundred and twenty-one middle school students were randomized to receive either an eight-session interpretation bias modification task (CBM-I; n = 61) or an eight-session placebo control task (PCT; n = 60) over four weeks. Measures of hostile attribution bias and cyber-aggression were administered at baseline, post-training, and at one week follow-up. Results showed that compared to PCT, participants in CBM-I showed a significant reduction in reactive cyber-aggression. However, contrary to our expectation, there was no significant difference between the two groups in the reduction of hostile attribution bias after training. The moderated mediation analysis revealed that the effect of CBM-I on hostile attribution bias and the mediating role of hostile attribution bias in the relationship between CBM-I condition and reactive cyber-aggression was only observed among females, but not among males. These findings provide initial evidence for the potential of CBM-I in reducing hostile attribution bias and cyber-aggression. However, for male students, CBM-I might not be effective enough as expected.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12144-023-04433-3.

Empowerment Mitigates Gender Differences in Tertius Iungens Brokering

Tertius iungens brokering that brings together people who might not otherwise meet is crucial for organizational effectiveness. But we know little about whether and why women and men differ in their propensity to engage in this brokering. Our paper focuses on the origins and mitigation of gender differences in the propensity to bring people together. In study 1, we showed that the Totterdell et al. [Totterdell P, Holman D, Hukin A (2008) Social networkers: Measuring and examining individual differences in propensity to connect with others. Soc. Networks 30(4):283–296] propensity-to-join-others scale that we used in study 2 and the Obstfeld [Obstfeld D (2005) Social networks, the tertius iungens orientation, and involvement in innovation. Admin. Sci. Quart. 50(1):100–130] tertius iungens scale overlapped not only conceptually, but also empirically, and that these measures of tertius iungens were distinct from mediation- and separation-brokering propensities [Grosser TJ, Obstfeld D, Labianca G, Borgatti SP (2019) Measuring mediation and separation brokerage orientations: A further step toward studying the social network brokerage process. Acad. Management Discoveries 5(2):114–136]. In study 2, we used a natural experiment to examine the tertius iungens brokering propensities of 876 identical and 625 fraternal same-sex twins. We found that brokering propensity was lower for women than for men, although the propensity toward sociability in terms of making friends and acquaintances was lower for men. We also found that for women, relative to men, tertius iungens brokering propensity was largely affected by environmental influences, such as the experience of stereotyping and discrimination, rather than representing an inherited disposition. Moreover, the differences between men and women with respect to brokering were mitigated for empowered samples, such as well-educated or entrepreneurial individuals. Our research asks new questions about how environmental pressures and empowerment affect social networking. Gender differences in brokering may be amenable to mitigation through empowering practices that include education and entrepreneurial experience.

Fetal androgen signaling defects affect pancreatic β-cell mass and function, leading to glucose intolerance in high-fat diet-fed male rats

We previously demonstrated that androgen signaling expands pancreatic β-cell mass in the sexual maturation period (Am J Physiol Endocrinol Metab 314: E274-E286, 2018). The aim of this study was to elucidate whether fetal androgen signaling plays important roles in β-cell mass development and β-cell function in adulthood, defects of which are associated with type 2 diabetes mellitus. In the pancreas of male fetuses, androgen receptor (AR) was strongly expressed in the cytoplasm and at the cell membrane of Nkx6.1-positive β-cell precursor cells but was markedly reduced in insulin-positive β-cells. Administration of the anti-androgen flutamide to pregnant dams during late gestation reduced β-cell mass and Ki67-positive proliferating β-cells at birth in a male-specific manner without affecting body weight. The decrease of β-cell mass in flutamide-exposed male rats was not recovered when rats were fed a standard diet, whereas it was fully recovered when rats were fed a high-fat diet (HFD), at 6 and 12 wk of age. Flutamide exposure in utero led to the development of glucose intolerance in male rats due to a decrease in insulin secretion when fed HFD but not standard diet. Insulin sensitivity did not differ between the two groups irrespective of diet. These results indicated that the action of fetal androgen contributed to β-cell mass expansion in a sex-specific manner at birth and to the development of glucose intolerance by decreasing the secretion of insulin in HFD-fed male rats. Our data demonstrated the involvement of fetal androgen signaling in hypothesized sex differences in the developmental origins of health and disease by affecting pancreatic β-cell function.

A Study on the Relationship between Urban Residents’ Perception of Recreational Sports and Their Participation in Recreational Sports: Based on Gender Differences

Background: The health of urban residents plays an important role in increasing the well-being of citizens, and therefore promoting the sustainable development of cities. Studies in Western countries have provided some evidence of the relationship between the urban residents’ perception of the recreational sports (RS), including perception of industry, space, experience, type, and support affecting recreational behaviors. Yet, evidence in China is not sufficient and, particularly, gender difference has not been discussed anywhere. Objectives: The present study aimed to see urban residents’ perception of RS and its effect on recreational sport participation by the residents. Method: The study was conducted in three big cities (Hangzhou, Chengdu, and Shanghai) of China to test the association between the urban residents’ perception of RS and their RS participation, in which gender differences were discussed. After taking their consent, a total of 764 participants (397 male and 367 female) aged from 15 to 65 were approached between April and October, 2018. The participants were given a survey to assess their perception and behavior of RS. T-test and the structural equation modeling were used to analyze gender differences in association between perception and behavior of RS. Results: For females, industry perception (β = 0.17, p = 0.00), space perception (females: β = 0.16, p = 0.00), and support perception (females: β = 0.09, p = 0.03) had a significant positive effect on RS participation. For males, industry perception (males: β = 0.13, p = 0.01) and type perception (males: β = 0.23, p = 0.00) showed a significant positive impact on participation of RS. However, space perception of males (β = −0.12; p = 0.01) and type perception of females (β = −0.11; p = 0.01) are negatively associated with their RS participation. The perception of experience was the most important factor influencing RS behaviors. Significant gender differences have appeared in all five different perception factors. The industry perception has significant and positive effects on both males and females’ RS participation. The type perception has significant positive effects on the male but negative on the female RS, while the space perception is just the opposite. The support perception has significant positive effects on the female RS practice but the influence is not obvious in the case of males. Conclusion: By adopting some measures, perception of RS may improve urban residents’ participation in RS.

Psychopathy in Italian female murderers

Over the years, the number of homicides in Italy has progressively decreased, ultimately becoming one of the lowest rates in Europe (357 = 0.7 per 100,000 inhabitants in 2017, according to ISTAT). The number of homicides committed by women was about 9% of the total number of homicides during our study period. The percentage has increased in recent years because the total number of homicides has decreased without a proportionate decrease in the number of female homicides. Indeed, murder is an unusual type of crime for a woman and is often associated with a mental disorder, so when a woman committed a homicide, a psychiatric assessment was often performed. A forensic psychiatry expert was assigned to investigate the offender's psychopathology and mental state at the time of the offense. The root causes of the crime remained unexplained, however, due to the lack of a psychiatric precedent to justify this kind of assessment. The role of psychopathy in homicide has seldom been studied in female offenders, even though psychopathy has an important role in violent crimes. The investigators examined, clinically and historically, a sample of women who committed murder with different levels of criminal responsibility (female homicide offenders found not guilty by reason of insanity, having partial criminal responsibility, and convicted as criminally responsible and sentenced to prison) to identify the prevalence of the psychopathic dimension and its possible role in this sample. Prevalence and degree of psychopathic traits were examined in these female offenders using the Psychopathy Checklist-Revised. This study showed that females who had committed homicide were likely to suffer from mental illness; most of the homicidal acts were committed impulsively; and most female homicides occurred within the family, especially among women who were psychotic, but less so if they were psychopathic. Psychopathy tended to co-occur more with personality disorders than with psychotic psychopathology. Psychopathy was more evident among female homicide offenders who had been abused or traumatized. Psychopathic women who killed had high factor F1 scores and low antisocial component of factor F2.

Role of androgens in energy metabolism affecting on body composition, metabolic syndrome, type 2 diabetes, cardiovascular disease, and longevity: lessons from a meta-analysis and rodent studies

Testosterone is a sex hormone produced by testicular Leydig cells in males. Blood testosterone concentrations increase at three time-periods in male life-fetal, neonatal (which can be separated into newborn and infant periods), and pubertal stages. After peaking in the early 20s, the blood bioactive testosterone level declines by 1-2% each year. It is increasingly apparent that a low testosterone level impairs general physical and mental health in men. Here, this review summarizes recent systematic reviews and meta-analyses of epidemiological studies in males (including cross-sectional, longitudinal, and androgen deprivation studies, and randomized controlled testosterone replacement trials) in relation to testosterone and obesity,  body composition, metabolic syndrome, type 2 diabetes, cardiovascular disease, and longevity. Furthermore, underlying mechanisms are discussed using data from rodent studies involving castration or androgen receptor knockout. This review provides an update understanding of the role of testosterone in energy metabolism. Abbreviations AR: androgen receptor; CV: cardiovascular; FDA: US Food and Drug Administration; HFD: high-fat diet; KO: knockout; MetS: metabolic syndrome; RCT: randomized controlled trial; SHBG: sex hormone binding globulin; SRMA: systematic review and meta-analysis; TRT: testosterone replacement therapy; T2DM:type 2 diabetes mellitus.

Human mating strategies: from past causes to present consequences

In both humans and nonhuman animals, mating strategies represent a set of evolutionary adaptations aimed at promoting individual fitness by means of reproduction with the best possible partners. Given this critical role, mating strategies influence numerous aspects of human life. In particular, between-sex divergence in the intensity of intrasexual competition could account for robust cross-cultural sex differences in psychology and behavior (e.g., personality, psychiatric disorders, social behavior, violence). Several other factors (including individual differences, relationship type and environment) affect-in an evolutionarily consistent manner-variation in mating strategy that individuals pursue (as one example, awareness of one's own attractiveness impinges on mating standards). Here we provide an overview of relevant theoretical frameworks and empirical evidence on variation in mating strategies. Given its multifaceted nature and intense research interest over several decades, this is a challenging task, and we highlight areas where further investigation is warranted in order to achieve a clearer picture and resolve apparent inconsistencies. However, we suggest that addressing outstanding questions using a variety of different methodological approaches, a deeper understanding of the cognitive representations involved in mating strategies is within reach. WIREs Cogn Sci 2018, 9:e1456. doi: 10.1002/wcs.1456 This article is categorized under: Cognitive Biology > Evolutionary Roots of Cognition Neuroscience > Behavior Neuroscience > Cognition.

Neuroscience Application to Noncontact Anterior Cruciate Ligament Injury Prevention

Context:

Many factors, including anatomy, neuromuscular control, hormonal regulation, and genetics, are known to contribute to the noncontact anterior cruciate ligament (ACL) injury risk profile. The neurocognitive and neurophysiological influences on the noncontact ACL injury mechanism have received less attention despite their implications to maintain neuromuscular control. Sex-specific differences in neurocognition may also play a critical role in the elevated female ACL injury risk. This report serves to frame existing literature in a new light to consider neurocognition and its implications for movement control, visual-motor function, and injury susceptibility.

Evidence Acquisition:

Sources were obtained from PubMed, MEDLINE, Web of Science, and LISTA (EBSCO) databases from 1990 onward and ranged from diverse fields including psychological and neuroscience reviews to injury epidemiology and biomechanical reports.

Study Design:

Clinical review.

Level of Evidence:

Level 5.

Results:

Neurological factors may contribute to the multifactorial ACL injury risk paradigm and the increased female injury susceptibility.

Conclusion:

When developing ACL injury prevention programs, considering neurocognition and its role in movement, neuromuscular control, and injury risk may help improve intervention effectiveness.

Hypogonadism alters cecal and fecal microbiota in male mice

Low testosterone levels increase the risk for cardiovascular disease in men and lead to shorter life spans. Our recent study showed that androgen deprivation via castration altered fecal microbiota and exacerbated risk factors for cardiovascular disease, including obesity, impaired fasting glucose, excess hepatic triglyceride accumulation, and thigh muscle weight loss only in high-fat diet (HFD)-fed male mice. However, when mice were administered antibiotics that disrupted the gut microbiota, castration did not increase cardiovascular risks or decrease the ratio of dried feces to food intake. Here, we show that changes in cecal microbiota (e.g., an increased Firmicutes/Bacteroidetes ratio and number of Lactobacillus species) were consistent with changes in feces and that there was a decreased cecal content secondary to castration in HFD mice. Castration increased rectal body temperature and plasma adiponectin, irrespective of diet. Changes in the gut microbiome may provide novel insight into hypogonadism-induced cardiovascular diseases.

Neural Correlates of Sex/Gender Differences in Humor Processing for Different Joke Types

Humor operates through a variety of techniques, which first generate surprise and then amusement and laughter once the unexpected incongruity is resolved. As different types of jokes use different techniques, the corresponding humor processes also differ. The present study builds on the framework of the 'tri-component theory of humor,' which details the mechanisms involved in cognition (comprehension), affect (appreciation), and laughter (expression). This study seeks to identify differences among joke types and between sexes/genders in the neural mechanisms underlying humor processing. Three types of verbal jokes, bridging-inference jokes (BJs), exaggeration jokes (EJs), and ambiguity jokes (AJs), were used as stimuli. The findings revealed differences in brain activity for an interaction between sex/gender and joke type. For BJs, women displayed greater activation in the temporoparietal-mesocortical-motor network than men, demonstrating the importance of the temporoparietal junction (TPJ) presumably for 'theory of mind' processing, the orbitofrontal cortex for motivational functions and reward coding, and the supplementary motor area for laughter. Women also showed greater activation than men in the frontal-mesolimbic network associated with EJs, including the anterior (frontopolar) prefrontal cortex (aPFC, BA 10) for executive control processes, and the amygdala and midbrain for reward anticipation and salience processes. Conversely, AJs elicited greater activation in men than women in the frontal-paralimbic network, including the dorsal prefrontal cortex (dPFC) and parahippocampal gyrus. All joke types elicited greater activation in the aPFC of women than of men, whereas men showed greater activation than women in the dPFC. To confirm the findings related to sex/gender differences, random group analysis and within group variance analysis were also performed. These findings help further establish the mechanisms underlying the processing of different joke types for the sexes/genders and provide a neural foundation for a theory of sex/gender differences in humor.

Personality and gender differences in global perspective

Men's and women's personalities appear to differ in several respects. Social role theories of development assume gender differences result primarily from perceived gender roles, gender socialization and sociostructural power differentials. As a consequence, social role theorists expect gender differences in personality to be smaller in cultures with more gender egalitarianism. Several large cross-cultural studies have generated sufficient data for evaluating these global personality predictions. Empirically, evidence suggests gender differences in most aspects of personality-Big Five traits, Dark Triad traits, self-esteem, subjective well-being, depression and values-are conspicuously larger in cultures with more egalitarian gender roles, gender socialization and sociopolitical gender equity. Similar patterns are evident when examining objectively measured attributes such as tested cognitive abilities and physical traits such as height and blood pressure. Social role theory appears inadequate for explaining some of the observed cultural variations in men's and women's personalities. Evolutionary theories regarding ecologically-evoked gender differences are described that may prove more useful in explaining global variation in human personality.

Criminality and the 2D:4D ratio: testing the prenatal androgen hypothesis

A decade old theory hypothesizes that brain exposure to androgens promotes involvement in criminal behavior. General support for this hypothesis has been provided by studies of postpubertal circulating levels of testosterone, at least among males. However, the theory also predicts that for both genders, prenatal androgens will be positively correlated with persistent offending, an idea for which no evidence currently exists. The present study used an indirect measure of prenatal androgen exposure-the relative length of the second and fourth fingers of the right hand (r2D:4D)-to test the hypothesis that elevated prenatal androgens promote criminal tendencies later in life for males and females. Questionnaires were administered to 2,059 college students in Malaysia and 1,291 college students in the United States. Respondents reported their r2D:4D relative finger lengths along with involvement in 13 categories of delinquent and criminal acts. Statistically significant correlations between the commission of most types of offenses and r2D:4D ratios were found for males and females even after controlling for age. It is concluded that high exposure to androgens during prenatal development contributes to most forms of offending following the onset of puberty.

An Underexamined Inequality

Social psychological research has sought to understand and mitigate the psychological barriers that block women’s interest, performance, and advancement in male-dominated, agentic roles (e.g., science, technology, engineering, and math). Research has not, however, correspondingly examined men’s underrepresentation in communal roles, traditionally occupied by women (e.g., careers in health care, early childhood education, and domestic roles including child care). In this article, we seek to provide a roadmap for research on this underexamined inequality by (a) outlining the benefits of increasing men’s representation in communal roles; (b) reviewing cultural, evolutionary, and historical perspectives on the asymmetry in status assigned to men’s and women’s roles; and (c) articulating the role of gender stereotypes in creating social and psychological barriers to men’s interest and inclusion in communal roles. We argue that promoting equal opportunities for both women and men requires a better understanding of the psychological barriers to men’s involvement in communal roles.

When the difference is in the details: a critique of Zentner and Mitura (2012) "Stepping out of the caveman's shadow: Nations' gender gap predicts degree of sex differentiation in mate preferences"

In a recent 10-nation study, Zentner and Mitura (2012) reported observing smaller sex differences in mate preferences within nations that have higher gender parity. As noted in previous research, and in a re-analysis of Zentner and Mitura's own data, sex differences in some mate preferences (e.g., long-term mate preferences for physical attractiveness) are either unrelated to or actually get larger with higher national gender parity. It is critically important to distinguish among mate preference domains when looking for patterns of sexual differentiation across nations. Indeed, for many psychological domains (e.g., attachment styles, Big Five traits, Dark Triad traits, self-esteem, personal values, depression, emotional expression, crying behavior, intimate partner violence, tested mental abilities, health indicators; see Schmitt, 2012), sex differences are demonstrably larger in nations with higher sociopolitical gender parity. By not distinguishing among mate preferences, Zentner and Mitura committed a form of the ecological fallacy-making false conclusions about individual mate preferences when looking only at associations among groups of mate preferences.

Capturing the psychopathic female: a prototypicality analysis of the comprehensive assessment of psychopathic personality (CAPP) across gender

Psychopathy in women has been subject to little systematic investigation; no coherent conceptualization of the disorder in women exists. Previous research is constrained by the reliance both on a male conceptualization of psychopathy and on assessment instruments developed, and primarily validated, with men. This study utilized a newly developed, broad, personality-based, and gender-sensitive lexical model of psychopathy, the Comprehensive Assessment of Psychopathic Personality (CAPP). Prototypical analysis was used to explore gender differences in the construct and the content validity of the CAPP model across gender. Symptoms were rated by international mental health professionals (N = 132). The findings support the content validity of the CAPP across gender and suggest that - at symptom and domain levels - psychopathic men and women have key similarities, but also that important gender differences exists. This has implications for the assessment of psychopathy in women, and has relevance for the proposed revision of diagnostic criteria for personality disorders.