Sex differences in children's free drawings: a study on girls with congenital adrenal hyperplasia

Through the eyes of the parents: a transdiagnostic psychiatric perspective for children with differences of sexual development

PURPOSE

Existing literature lacks data on a subgroup exhibiting psychiatric symptoms below the DSM-5 diagnostic threshold within DSD cases. Our study aims to assess parental knowledge, attitudes toward DSD, and parental perceptions of emotional and behavioral states through a transdiagnostic perspective.

METHODS

The study was conducted with a total of 35 parents of children with DSD. Two groups were established via k-means clustering, based on psychiatric symptomatology levels, derived from The Strength and Difficulties Questionnaire - Parent Form and The Revised Children's Anxiety and Depression Scale - Parent Form: with one group exhibiting lower reported psychiatric symptoms (LPS=27) and the other demonstrating higher psychiatric symptoms (HPS=8) by parents.

RESULTS

Our study found that many parents were hesitant to disclose DSD diagnoses to their children, believing them to be too young to comprehend the information (42.9 %) and that they were unaware of the available support that could be provided by the medical team in disclosing the diagnosis (25.7 %). Our study found no differences in DSM-5 diagnoses between HPS and LPS groups (p>0.05), with ADHD being the most prevalent diagnosis (21.7 %) and a significant overrepresentation of children with a discrepancy between assigned gender at birth and gender upbringing in the HPS group compared to the LPS group (p<0.001).

CONCLUSIONS

Our study emphasizes the necessity of a transdiagnostic approach in psychiatry to move beyond binary conceptualizations and better understand the complexities of individuals with DSD.

Machine learning trial to detect sex differences in simple sticker arts of 1606 preschool children

BACKGROUND

Previous studies suggested that drawings made by preschool boys and girls show distinguishable differences. However, children's drawings on their own are too complexly determined and inherently ambiguous to be a reliable indicator. In the present study, we attempted to develop a machine learning algorithm for classification of sex of the subjects using children's artworks.

METHODS

We studied three types of simple sticker artworks from 1606 Japanese preschool children aged 51-83 months (803 boys and 803 girls). Those artworks were processed into digitalized data. Simulated data based on the original data were also generated. Logistic regression approach was applied to each dataset to make a classifier, and run on each dataset in a stratified ten-fold cross-validation with hyperparameter tuning. A probability score was calculated in each sample and utilized for sex classification. Prediction performance was evaluated using accuracy, recall, and precision scores, as well as learning curves.

RESULTS

Two models created from the original and simulated data showed comparably low metrics. The distributions of probability scores in the samples from boys and girls mostly overlapped and were indistinguishable. Learning curves of the models showed an extremely under-fitted pattern.

CONCLUSIONS

Our machine learning algorithm was unable to distinguish simple sticker arts created by boys and girls. More complex tasks will enable to develop an accurate classifier.

Is it possible to estimate sex from signatures and handwriting? A review of literature, observations, and future perspectives

Estimation of sex holds great significance in the field of Forensic Science since it helps establish the identity of an individual during a crime scene investigation. Sex differences in human behaviour are the result of natural selection. Sexually dimorphic stimuli of cognitive and behavioural activities may influence the phenotypic expression of our motor skills. Human traits such as signatures and handwriting are phenotypic manifestation of these skills. These phenotypic biological and behavioural traits have inherent sexual dimorphism and may help to identify sex in different circumstances. For instance, to establish the sex of an individual or deceased, forensic samples of the human body such as voice samples, features of fingerprints and footprints, the skeleton, or its remains are helpful. Similarly, the sex of an individual may also be identified from their corresponding handwriting and signature. Handwriting experts can extract peculiar features from handwriting and signatures which could help establish whether the signatures belong to a male or a female. A female writer may have attractive, rounded, upright, tidy, skilled, well-formed strokes, artistic design, better penmanship, and greater length of the signature compared to the signature of a male. Here, we review the studies related to the identification of sex from signatures and handwriting and present inferences about vital features and methods of sex identification through handwriting. These mainly suggest that the accuracy of sex prediction from signature and handwriting ranges from 45 to 80%. We also present writing examples to show sex-based differences in the signature and handwriting of males and females. The female's handwriting is more decorative, arranged, aligned, neat, and clean as compared to that of the male. Based on the writing samples and the review of literature, we suggest that forensic handwriting experts may eliminate suspects based on the sex of the writer, which can simplify the identification process of disputed or questionable signatures and handwriting.

Red background color biases gender categorization of human faces

Color carries gender information (e.g., red-female). This study explored whether background color could influence the gender categorization of human faces. Visual stimuli were generated from faces whose sexually dimorphic content was morphed monotonically from female to male perception. The face stimulus was presented upright (Experiment 1) and inverted (Experiment 2) with three background colors (i.e., red, green, and gray). Participants were instructed to categorize the gender of the face stimulus as male or female by pressing one of two labelled keys. Results showed that a red background could bias the gender of an ambiguous upright face toward a female compared with green and gray background colors (Experiment 1). However, this red effect was diminished when the face stimulus was inverted (Experiment 2). These results suggest that red background color interacting with facial configuration features biases gender perception toward a female face, possibly through top-down processing of learned associations between the color red and femininity.

Sex differences matter: Males and females are equal but not the same

Sex differences between males and females can be detected early in life. They are present also later even to a much greater extent affecting our life in adulthood and a wide spectrum of physical, psychological, cognitive, and behavioral characteristics. Moreover, sex differences matter also in individual's health and disease. In this article, we reviewed at first the sex differences in brain organization and function with respect to the underlying biological mechanisms. Since the individual functional differences in the brain, in turn, shape the behavior, sex-specific psychological/behavioral differences that can be observed in infants but also adults are consequently addressed. Finally, we briefly mention sex-dependent variations in susceptibility to selected disorders as well as their pathophysiology, diagnosis, and response to therapy. The understanding of biologically determined variability between males and females can have important implications, especially in gender-specific health care. We have the impression that it is very important to emphasize that sex matters. Males and females are differently programmed by nature, and it must be respected. Even though we as males and females are not the same, we would like to emphasize that we are still equal and together form a worthy colorful continuum.

The sexual selection of creativity: A nomological approach

Cultural innovations, such as tools and other technical articles useful for survival, imply that creativity is an outcome of evolution. However, the existence of purely ornamental items obfuscates the functional value of creativity. What is the functional or adaptive value of aesthetic and intellectual ornaments? Recent evidence shows a connection between ornamental creativity, an individual's attractiveness, and their reproductive success. However, this association is not sufficient for establishing that creativity in humans evolved by sexual selection. In this critical review, we synthesize findings from many disciplines about the mechanisms, ontogeny, phylogeny, and the function of creativity in sexual selection. Existing research indicates that creativity has the characteristics expected of a trait evolved by sexual selection: genetic basis, sexual dimorphism, wider variety in males, influence of sex hormones, dysfunctional expressions, an advantage in mating in humans and other animals, and psychological modules adapted to mating contexts. Future studies should investigate mixed findings in the existing literature, such as creativity not being found particularly attractive in a non-WEIRD society. Moreover, we identified remaining knowledge gaps and recommend that further research should be undertaken in the following areas: sexual and reproductive correlates of creativity in non-WEIRD societies, relationship between androgens, development, and creative expression, as well as the impact of ornamental, technical and everyday creativity on attractiveness. Evolutionary research should analyze whether being an evolved signal of genetic quality is the only way in which creativity becomes sexually selected and therefore passed on from generation to generation. This review has gone a long way toward integrating and enhancing our understanding of ornamental creativity as a possible sexual selected psychological trait.

Transformation of Children's Paintings into Public Art to Improve Public Spaces and Enhance People's Happiness

Characteristics of children's paintings have been suggested considered for application in public art since they are known to positively evoke a sense of well-being when people see them. This study aims to understand the impact of artistic features from children's drawings on people's well-being; then analyzing the adaptive design principles of 3D public art featuring children's paintings on people's happiness; and finally, exploring the influence of 3D public art featuring children's paintings on improving public spaces and enhancing people's well-being. The results lead to proposing a conceptual framework for public artworks in public spaces for improving people's happiness. The proposed conceptual framework recommends that, by applying the visual and thinking features of children's paintings to public art, artists can design high-quality artworks suitable for a city, which could improve people's happiness in public spaces. This study recommends further research into how public art can promote public spaces and shape the urban culture. It contributes to enhancing the quality of public art and public spaces, and inspiring a sense of well-being among citizens through the use of appropriate public art. The results are significant because they will help artists to create more high-quality public artworks for urban public spaces in order to evoke people's happiness.

Gender Development in Gender Diverse Children

Within "mainstream" developmental science, gender researchers largely study the developmental trajectory of children considered to be "gender-typical", while research housed primarily in psychiatry and clinical psychology often documents the trajectories of gender diverse children. This article aims to bridge the studies of gender diversity and "mainstream" gender development. First, we review literature on the development of four commonly studied subgroups of gender diverse children - children referred to medical clinics because of their gender identity and expression, transgender children, female children with congenital adrenal hyperplasia, and tomboys - highlighting how these gender trajectories do or do not align with modal developmental patterns. We then describe social, cognitive, and biological determinants of gender in light of their implications for understanding diverse gender development. Finally, we note methodological suggestions for future research, with an eye toward better integrating research on gender diversity into "mainstream" gender development research.

Draw yourself: How culture influences drawings by children between the ages of two and fifteen

The place children live strongly influence how they develop their behavior, this is also true for pictorial expression. This study is based on 958 self-portraits drawn by children aged 2-15 years old from 35 countries across 5 continents. A total of 13 variables were extracted of each drawing allowing us to investigate the differences of individuals and environment representations in these drawings. We used a principal component analysis to understand how drawing characteristics can be combined in pictorial concepts. We analyzed the effect of age, gender, socioeconomic, and cultural factors in terms of complexity and inclusion of social (human figures) and physical (element from Nature and man-made elements) environments, their frequencies, size, and proportions of these elements on each drawing. Our results confirm the existence of cultural variations and the influence of age on self-portrait patterns. We also observed an influence of physical and socio-cultural contexts through the level of urbanization and the degree of individualism of the countries, which have affected the complexity, content and representation of human figures in the drawings studied.

Sexual differentiation of the human hypothalamus: Relationship to gender identity and sexual orientation

Gender identity (an individual's perception of being male or female) and sexual orientation (heterosexuality, homosexuality, or bisexuality) are programmed into our brain during early development. During the intrauterine period in the second half of pregnancy, a testosterone surge masculinizes the fetal male brain. If such a testosterone surge does not occur, this will result in a feminine brain. As sexual differentiation of the brain takes place at a much later stage in development than sexual differentiation of the genitals, these two processes can be influenced independently of each other and can result in gender dysphoria. Nature produces a great variability for all aspects of sexual differentiation of the brain. Mechanisms involved in sexual differentiation of the brain include hormones, genetics, epigenetics, endocrine disruptors, immune response, and self-organization. Furthermore, structural and functional differences in the hypothalamus relating to gender dysphoria and sexual orientation are described in this review. All the genetic, postmortem, and in vivo scanning observations support the neurobiological theory about the origin of gender dysphoria, i.e., it is the sizes of brain structures, the neuron numbers, the molecular composition, functions, and connectivity of brain structures that determine our gender identity or sexual orientation. There is no evidence that one's postnatal social environment plays a crucial role in the development of gender identity or sexual orientation.

Human gender development

Human gender-related behavior/psychology is shaped by a developmental system that involves numerous influences interacting over time. Understanding of the full range of elements in the system and how they interact is currently incomplete. The available evidence suggests, however, that early exposure to testosterone, postnatal socialization, e.g., by parents and peers, and self-socialization related to cognitive understanding of gender are important elements. This article focuses on prenatal and early neonatal influences of testosterone on gender-related psychological/behavioral outcomes, and contextualizes these hormonal influences within an understanding of socialization influences. There is consistent evidence that early testosterone exposure influences childhood gender role behavior, including sex-typical toy play, as well as gender identity and sexual orientation. Evidence for similar hormonal influences on spatial ability and on traits related to autism, or autistic spectrum disorder, is inconsistent. Evidence from girls exposed to elevated testosterone prenatally suggests that they experience alterations in processes of external socialization, as well as self-socialization, and that these, along with early testosterone exposure, shape gender-related outcomes.

Gender dysphoria and XX congenital adrenal hyperplasia: how frequent is it? Is male-sex rearing a good idea?

INTRODUCTION

The frequency of gender dysphoria (GD) among 46,XX congenital adrenal hyperplasia (CAH) patients is unknown. These data are needed to put into perspective the debate about the timing of reconstructive surgery and possible male-raising of the most severely virilized children.

OBJECTIVE

To analyze the frequency of female to male GD between 46,XX individuals raised as females; to identify subgroups with higher chances of showing GD; to describe the results of male-raising among 46,XX CAH patients.

MATERIALS AND METHODS

Analytic/descriptive literature review (January 1988 to April 2018).

RESULTS

Female-raised patients frequently report the desire to be male, adopt male-typical behavior and are frequently homosexual/bisexual as adults, but this does not correspond to GD. Declared GD among 46,XX CAH patients attained 9% of the reported cohorts, generally in late adolescence/adulthood. We could not prove a relationship between inadequate treatment, null-genotype, late diagnoses, a higher degree of virilization, type of CAH or higher levels of androgens and female to male GD, but this may be due to statistical limitations. Male gender raised patients (MGR) were 10.1% of CAH cohorts included in this review, mostly from underdeveloped countries, with a high proportion of late diagnoses (76.3%) and familial choices. GD was more common in this group than among female-raised patients. Opting for male gender relates to a short final height, the need for multiple surgeries, surgical castration before puberty and infertility.

CONCLUSION

Both male to female and female to male GD may present in 46,XX CAH patients in a contemporaneous cohort. The proportion of GD is higher among patients raised as males. DSD patients sexual maladjustments are complex and not comparable to the transgender population. Many 46,XX CAH patients with GD define themselves as gender-fluid and do not seek for legal/formal transition. Male-raising Prader 4/5 46,XX CAH patients imply infertility and multiple surgeries. There is no proof that any subgroup of CAH is more prone to GD, despite null genotypes, salt wasting phenotypes and Prader 4/5 cases being related to male-typical behavior and female homosexuality.

TYPE OF STUDY

Descriptive/analytic non-systematic REVIEW.

LEVEL OF EVIDENCE

3.

Neurodiversity and Artistic Performance Characteristic of Children With Autism Spectrum Disorder

Neurodiversity refers to the notion that seemingly 'impaired' cognitive as well as emotional features characteristic of developmental disorders such as autism spectrum disorder (ASD) fall into normal human behavioral variations that should enjoy some selective advantages. In the present experiment, the author compared what was depicted in subjects' drawings after they experienced an identical event, e.g., going on a picnic to a garden in the vicinity of their nursery school, between children with ASD and IQ-matched, typically developing (TD) children. When the material was coded according to types of drawn objects, such as human, animal, plant, food, vehicle, building, and others, the overall variability of the objects did not differ between TD children and children with ASD. However, TD children were more likely than children with ASD to depict human images. Conversely, other objects were more likely to be drawn by children with ASD than by TD children. While TD children were more likely to focus on humans than on non-human objects when drawing, children with ASD were more likely to focus on non-human objects than on humans even after both had experienced an identical event. The author argues that such findings are empirical evidence for the claim that there is some selective advantage of enhanced capabilities characteristic of ASD, i.e., neurodiversity, that may represent a balance toward "folk physics" at the expense of "folk psychology."

Gender and creativity: an overview of psychological and neuroscientific literature

The topic of gender differences in creativity is one that generates substantial scientific and public interest, but also courts considerable controversy. Owing to the heterogeneous nature of the findings associated with this line of research, the general picture often appears puzzling or obscure. This article presents a selective overview of psychological and neuroscientific literature that has a relevant bearing on the theme of gender and creativity. Topics that are explored include the definition and methods of assessing creativity, a summary of behavioral investigations on gender in relation to creativity, postulations that have been put forward to understand gender differences in creative achievement, gender-based differences in the structure and function of the brain, gender-related differences in behavioral performance on tasks of normative cognition, and neuroscientific studies of gender and creativity. The article ends with a detailed discussion of the idea that differences between men and women in creative cognition are best explained with reference to the gender-dependent adopted strategies or cognitive style when faced with generative tasks.

CAN BODY PROPORTIONS SERVE AS A PREDICTOR OF RISK-TAKING BEHAVIOURS IN WOMEN AND MEN?

The second to fourth digit ratio (2D:4D) is claimed to be a biomarker of prenatal sex steroids. This study compared 2D:4D and waist-hip ratio (WHR) in men and women with nose deformity caused by injuries suggesting risky behaviour with those of unaffected controls. This kind of facial trauma was accepted as an indicator of risk-taking behaviour. The study involved 100 patients (50 women aged 30.74±8.09 years and 50 men aged 30.98±10.86 years) who underwent rhinoplasty due to nose trauma in a hospital in Łódź, Poland, in 2015. For comparison purposes, a control sample of 70 women (aged 23.03±3.36 years) and 70 men (aged 22.87±3.46 years) was recruited. In both groups the following measurements were taken: body height, waist and hip circumferences, II and IV digit lengths and body weight. The results showed that women and men who had suffered nose injury had significantly higher values of WHR than controls. The 2D:4D in women with post-traumatic nose deformity was significantly different than the ratio in control women (p<0.0001) and presented the male pattern. It is concluded that in women risky behaviours seem to be associated with prenatal sex hormone influence, while differences in WHR suggest that this tendency is also related to postnatal hormonal factors. Risky behaviours in men should be linked to postnatal hormonal changes rather than to increased prenatal androgen exposure.

Gender difference in the theta/alpha ratio during the induction of peaceful audiovisual modalities

Gender differences in emotional perception have been found in numerous psychological and psychophysiological studies. The conducting modalities in diverse characteristics of different sensory systems make it interesting to determine how cooperation and competition contribute to emotional experiences. We have previously estimated the bias from the match attributes of auditory and visual modalities and revealed specific brain activity frequency patterns related to a peaceful mood. In that multimodality experiment, we focused on how inner-quiet information is processed in the human brain, and found evidence of auditory domination from the theta-band activity. However, a simple quantitative description of these three frequency bands is lacking, and no studies have assessed the effects of peacefulness on the emotional state. Therefore, the aim of this study was to use magnetoencephalography to determine if gender differences exist (and when and where) in the frequency interactions underpinning the perception of peacefulness. This study provides evidence of auditory and visual domination in perceptual bias during multimodality processing of peaceful consciousness. The results of power ratio analyses suggest that the values of the theta/alpha ratio are associated with a modality as well as hemispheric asymmetries in the anterior-to-posterior direction, which shift from right to left with the auditory to visual stimulations in a peaceful mood. This means that the theta/alpha ratio might be useful for evaluating emotion. Moreover, the difference was found to be most pronounced for auditory domination and visual sensitivity in the female group.

Gender differences in creative thinking: behavioral and fMRI findings

Gender differences in creativity have been widely studied in behavioral investigations, but this topic has rarely been the focus of neuroscientific research. The current paper presents follow-up analyses of a previous fMRI study (Abraham et al., Neuropsychologia 50(8):1906-1917, 2012b), in which behavioral and brain function during creative conceptual expansion as well as general divergent thinking were explored. Here, we focus on gender differences within the same sample. Conceptual expansion was assessed with the alternate uses task relative to the object location task, whereas divergent thinking was assessed in terms of responses across both the alternate uses and object location tasks relative to n-back working memory tasks. While men and women were indistinguishable in terms of behavioral performance across all tasks, the pattern of brain activity while engaged in the tasks in question was indicative of strategy differences between the genders. Brain areas related to semantic cognition, rule learning and decision making were preferentially engaged in men during conceptual expansion, whereas women displayed higher activity in regions related to speech processing and social perception. During divergent thinking, declarative memory related regions were strongly activated in men, while regions involved in theory of mind and self-referential processing were more engaged in women. The implications of gender differences in adopted strategies or cognitive style when faced with generative tasks are discussed.

Sex differences in college students' free drawings and their relationship to 2D:4D ratio and recalled childhood play behavior

In a prior study, we observed that female-typical characteristics in elementary school girls' drawings were correlated with a feminized digit ratio (2D:4D), a marker for prenatal androgen exposure. However, this observation was limited to older girls, suggesting that social factors mediate the relationship between 2D:4D and drawing. To examine the hypothesis that the influence of prenatal androgen on girls' drawing is mediated by an effect of early androgens on sex-typical behavior, we examined 2D:4D, free drawings, and scores on the Recalled Childhood Gender Identity (RCGI) Questionnaire in a population of college students. Characteristics of participants' free drawings were assessed and those that showed sex differences were compared with 2D:4D and RCGI scores. Men had smaller 2D:4D ratios than women, used fewer total colors, used fewer pinks, purples, and blues, and had higher gender-typical scores on the RCGI. Women's drawings were more likely to contain flowers and animals and men's drawings were more likely to represent sports. Within-sex RCGI and 2D:4D scores were not significantly correlated. Significant within-sex relationships between 2D:4D and RCGI and drawing behavior were observed but the effects appeared to be independent; the hypothesis that gender-typical childhood behavior mediates the effect of prenatal androgen on drawing characteristics was not supported.

Psychiatric approaches for disorders of sex development: experience of a multidisciplinary team

OBJECTIVE

Disorders of sex development (DSD) are a group of congenital medical conditions that affect life as a whole. In this study, we aimed to reflect the experience of a multidisciplinary team in the clinical/psychiatric follow-up of a group of children and adolescents with DSD.

METHODS

The study group consisted of 51 patients diagnosed with DSD. The Kiddie-Schedule for Affective Disorders and Schizophrenia, Wechsler Intelligence Scale for Children-Revised, Draw a Person Test and Children's Apperception Test, and the Clinical Global Impression Scale (CGIS) were used for psychiatric evaluations.

RESULTS

The mean age of the patients was 7.8 years (median: 7.8; min: 1.0; max: 18.0). Genetic evaluation showed 46,XX configuration in 15 patients (29.4%) and 46,XY in 35 (68.6%). One patient (2.0%) was diagnosed to have a sex chromosome disorder. Forty patients (78.4%) had no problems with their given gender identity and gender role. Thirty-four (66.7%) patients had normal intellectual capacity. Twenty-eight (54.9%) patients did not have any psychiatric problem. Depression, anxiety disorders, attention deficit/hyperactivity disorder, and adjustment disorders were the common diagnoses. The mean score of symptom severity on CGIS-severity-baseline was 6.15±0.68 and after one year, it was 1.46±0.51 (Z=-3.236 p=0.001). The mean score of CGI-Improvement was 1.23±0.44.

CONCLUSION

It is important to identify and treat the psychiatric disorders encountered in patients with DSD. A psychiatrist needs to be included in the professional team following these patients. Examination and observation results need to be shared by holding periodic team meetings to establish a wholesome point of view for every unique child.

Sexual differentiation of the brain in man and animals: of relevance to Klinefelter syndrome?

The developing brain is highly sensitive to the organizing effects of steroids of gonadal origin in a process referred to as sexual differentiation. Early hormone effects prime the brain for adult sensitivity to the appropriate hormonal milieu, maximizing reproductive fitness via coordinated physiology and behavior. Animal models, in particular rodents, have provided insight into general principles and the cellular and molecular mechanisms of brain differentiation. Cellular endpoints influenced by steroids in the developing brain include neurogenesis, migration, apoptosis, dendritic growth, and synaptic patterning. Important roles for prostaglandins, endocanabinoids, and epigenetics are among the many cellular mediators of hormonal organization. Transference of general principles of brain sexual differentiation to humans relies on observations of individuals with genetic anomalies that either increase or decrease hormone exposure and sensitivity. The physiology and behavior of individuals with XXY (Klinefelter syndrome) has not been considered in the context of sexual differentiation of the brain, most likely due to the delay in diagnoses and highly variable presentation. The behavioral phenotype and impairments in the domains of speech and language that are characteristic of individuals with XXY is consistent with the reduced androgen production associated with the syndrome. Hormone replacement appears effective in restoring some deficits and impact may be further improved by increased understanding of the hormonally mediated sexual differentiation of the brain.

Men and women exhibit a differential bias for processing movement versus objects

Sex differences in many spatial and verbal tasks appear to reflect an inherent low-level processing bias for movement in males and objects in females. We explored this potential movement/object bias in men and women using a computer task that measured targeting performance and/or color recognition. The targeting task showed a ball moving vertically towards a horizontal line. Before reaching the line, the ball disappeared behind a masking screen, requiring the participant to imagine the movement vector and identify the intersection point. For the color recognition task, the ball briefly changed color before disappearing beneath the mask and participants were required only to identify the color shade. Results showed that targeting accuracy for slow and fast moving balls was significantly better in males compared to females. No sex difference was observed for color shade recognition. We also studied a third, dual attention task comprised of the first two, where the moving ball briefly changed color randomly just before passing beneath the masking screen. When the ball changed color, participants were required only to identify the color shade. If the ball didn't change color, participants estimated the intersection point. Participants in this dual attention condition were first tested with the targeting and color tasks alone and showed results that were similar to the previous groups tested on a single task. However, under the dual attention condition, male accuracy in targeting, as well as color shade recognition, declined significantly compared to their performance when the tasks were tested alone. No significant changes were found in female performance. Finally, reaction times for targeting and color choices in both sexes correlated highly with ball speed, but not accuracy. Overall, these results provide evidence of a sex-related bias in processing objects versus movement, which may reflect sex differences in bottom up versus top-down analytical strategies.

The effects of user factors and symbol referents on public symbol design using the stereotype production method

This study investigated the influence of user factors and symbol referents on public symbol design among older people, using the stereotype production method for collecting user ideas during the symbol design process. Thirty-one older adults were asked to draw images based on 28 public symbol referents and to indicate their familiarity with and ease with which they visualised each referent. Differences were found between the pictorial solutions generated by males and females. However, symbol design was not influenced by participants' education level, vividness of visual imagery, object imagery preference or spatial imagery preference. Both familiar and unfamiliar referents were illustrated pictorially without much difficulty by users. The more visual the referent, the less difficulty the users had in illustrating it. The findings of this study should aid the optimisation of the stereotype production method for user-involved symbol design.

Early-life soy exposure and gender-role play behavior in children

BACKGROUND

Soy-based infant formula contains high levels of isoflavones. These estrogen-like compounds have been shown to induce changes in sexually dimorphic behaviors in animals exposed in early development.

OBJECTIVE

We examined gender-role play behavior in relation to soy-based and non-soy-based infant feeding methods among children in the Avon Longitudinal Study of Parents and Children.

METHODS

We studied 3,664 boys and 3,412 girls. Four exposure categories were created using data from questionnaires administered at 6 and 15 months postpartum: primarily breast, early formula (referent), early soy, and late soy. Gender-role play behavior was assessed using the Pre-School Activities Inventory (PSAI). Associations between infant feeding and PSAI scores at 42 months of age were assessed using linear regression. Post hoc analyses of PSAI scores at 30 and 57 months were also conducted.

RESULTS

Early-infancy soy use was reported for approximately 2% of participants. Mean [95% confidence interval (CI)] PSAI scores at 42 months were 62.3 (62.0, 62.6) and 36.9 (36.6, 37.2) for boys and girls, respectively. After adjustment, early soy (vs. early formula) feeding was associated with higher (less feminine) PSAI scores in girls (β = 2.66; 95% CI: 0.19, 5.12) but was not significantly associated with PSAI scores in boys. The association between soy exposure and PSAI scores in girls was substantially attenuated at 30 and 57 months.

CONCLUSIONS

Although not consistent throughout childhood, early-life soy exposure was associated with less female-typical play behavior in girls at 42 months of age. Soy exposure was not significantly associated with play behavior in boys.

Oxytocin and social motivation

Humans are fundamentally social creatures who are ‘motivated’ to be with others. In this review we examine the role of oxytocin (OT) as it relates to social motivation. OT is synthesized in the brain and throughout the body, including in the heart, thymus, gastrointestinal tract, as well as reproductive organs. The distribution of the OT receptor (OTR) system in both the brain and periphery is even more far-reaching and its expression is subject to changes over the course of development. OTR expression is also sensitive to changes in the external environment and the internal somatic world. The OT system functions as an important element within a complex, developmentally sensitive biobehavioral system. Other elements include sensory inputs, the salience, reward, and threat detection pathways, the hypothalamic-pituitary-gonadal axis, and the hypothalamic-pituitary-adrenal stress response axis. Despite an ever expanding scientific literature, key unresolved questions remain concerning the interplay of the central and peripheral components of this complex biobehavioral system that dynamically engages the brain and the body as humans interact with social partners over the course of development.

Sexual differentiation of human behavior: effects of prenatal and pubertal organizational hormones

A key question concerns the extent to which sexual differentiation of human behavior is influenced by sex hormones present during sensitive periods of development (organizational effects), as occurs in other mammalian species. The most important sensitive period has been considered to be prenatal, but there is increasing attention to puberty as another organizational period, with the possibility of decreasing sensitivity to sex hormones across the pubertal transition. In this paper, we review evidence that sex hormones present during the prenatal and pubertal periods produce permanent changes to behavior. There is good evidence that exposure to high levels of androgens during prenatal development results in masculinization of activity and occupational interests, sexual orientation, and some spatial abilities; prenatal androgens have a smaller effect on gender identity, and there is insufficient information about androgen effects on sex-linked behavior problems. There is little good evidence regarding long-lasting behavioral effects of pubertal hormones, but there is some suggestion that they influence gender identity and perhaps some sex-linked forms of psychopathology, and there are many opportunities to study this issue.

Sexual differentiation of the human brain: relation to gender identity, sexual orientation and neuropsychiatric disorders

During the intrauterine period a testosterone surge masculinizes the fetal brain, whereas the absence of such a surge results in a feminine brain. As sexual differentiation of the brain takes place at a much later stage in development than sexual differentiation of the genitals, these two processes can be influenced independently of each other. Sex differences in cognition, gender identity (an individual's perception of their own sexual identity), sexual orientation (heterosexuality, homosexuality or bisexuality), and the risks of developing neuropsychiatric disorders are programmed into our brain during early development. There is no evidence that one's postnatal social environment plays a crucial role in gender identity or sexual orientation. We discuss the relationships between structural and functional sex differences of various brain areas and the way they change along with any changes in the supply of sex hormones on the one hand and sex differences in behavior in health and disease on the other.

Sex differences in the brain, behavior, and neuropsychiatric disorders

Sex differences in the brain are reflected in behavior and in the risk for neuropsychiatric disorders. The fetal brain develops in the male direction due to a direct effect of testosterone on the developing neurons, or in the female direction due to the absence of such a testosterone surge. Because sexual differentiation of the genitals takes place earlier in intrauterine life than sexual differentiation of the brain, these two processes can be influenced independently of each other. Gender identity (the conviction of belonging to the male or female gender), sexual orientation (heterosexuality, homosexuality, or bisexuality), pedophilia, sex differences in cognition, and the risks for neuropsychiatric disorders are programmed into our brains during early development. There is no proof that postnatal social environment has any crucial effect on gender identity or sexual orientation. Structural and functional sex differences in brain areas, together with changes in sex hormone levels and their receptors in development and adulthood, are closely related to sex differences in behavior and neuropsychiatric disorders. Knowing that such a relationship exists may help bring about sex-specific therapeutic strategies.

What can development teach us about menopause?

Development and aging are often mirror image processes and this may be equally true in the effects of estradiol, a potent endogenous steroid regulating brain development as well as a therapeutic used to relieve the negative components of perimenopause. Both the developing and perimenopausal brain are characterized by a sensitive period of hormone responsiveness, and in both cases, the neurotransmitters GABA and glutamate, as well as synaptogenesis and cell proliferation are major hormone targets. This review compares and contrasts the effects of estradiol on the developing and aging brain and highlights new avenues of exploration and therapeutic development.

Infants' preferences for toys, colors, and shapes: sex differences and similarities

Girls and boys differ in their preferences for toys such as dolls and trucks. These sex differences are present in infants, are seen in non-human primates, and relate, in part, to prenatal androgen exposure. This evidence of inborn influences on sex-typed toy preferences has led to suggestions that object features, such as the color or the shape of toys, may be of intrinsically different interest to males and females. We used a preferential looking task to examine preferences for different toys, colors, and shapes in 120 infants, ages 12, 18, or 24 months. Girls looked at dolls significantly more than boys did and boys looked at cars significantly more than girls did, irrespective of color, particularly when brightness was controlled. These outcomes did not vary with age. There were no significant sex differences in infants' preferences for different colors or shapes. Instead, both girls and boys preferred reddish colors over blue and rounded over angular shapes. These findings augment prior evidence of sex-typed toy preferences in infants, but suggest that color and shape do not determine these sex differences. In fact, the direction of influence could be the opposite. Girls may learn to prefer pink, for instance, because the toys that they enjoy playing with are often colored pink. Regarding within sex differences, as opposed to differences between boys and girls, both boys and girls preferred dolls to cars at age 12-months. The preference of young boys for dolls over cars suggests that older boys' avoidance of dolls may be acquired. Similarly, the sex similarities in infants' preferences for colors and shapes suggest that any subsequent sex differences in these preferences may arise from socialization or cognitive gender development rather than inborn factors.

Congenital adrenal hyperplasia: classification of studies employing psychological endpoints

Psychological outcomes in persons with congenital adrenal hyperplasia (CAH) have received substantial attention. The objectives of this paper were to (1) catalog psychological endpoints assessed in CAH outcome studies and (2) classify the conceptual/theoretical model shaping the research design and interpretation of CAH-related psychological effects. A total of 98 original research studies, published between 1955 and 2009, were categorized based on psychological endpoints examined as well as the research design and conceptual model guiding analysis and interpretation of data. The majority of studies (68%) investigated endpoints related to psychosexual differentiation. The preponderance of studies (76%) examined a direct relationship (i.e., inferring causality) between prenatal androgen exposure and psychological outcomes. Findings are discussed in relation to the observed imbalance between theoretical interest in the role of prenatal androgens in shaping psychosexual differentiation and a broader conceptual model that examines the role of other potential factors in mediating or moderating the influence of CAH pathophysiology on psychological outcomes in both affected females and males. The latter approach offers to identify factors amenable to clinical intervention that enhance both health and quality of life outcomes in CAH as well as other disorders of sex development.

Learning disabilities spectrum and sexual dimorphic abilities in girls with congenital adrenal hyperplasia

Congenital adrenal hyperplasia could provide a promising model for the study of the effects of hormones on cognition. The aim of this study was to assess sexual dimorphic abilities related to oral language, spatial abilities, and verbal fluency and to determine the existence of learning disabilities in 11 congenital girls with adrenal hyperplasia compared with 11 healthy girls. Both groups underwent a neuropsychological evaluation using the Child Neuropsychological Assessment battery for Spanish-speaking children. Results showed that the congenital adrenal hyperplasia group had a significantly lower performance than the control group in the repetition and expression domains, right-left comprehension task, and verbal semantic fluency task. A higher incidence of learning disabilities (predominantly reading related) in the patient group compared with their controls was also evident. Thus, the presence of weak verbal areas along with a high incidence of learning disabilities related primarily, though not exclusively, to reading was documented in these girls.