Gender-typed play and amniotic testosterone.

Sex differences in play are apparent in a number of mammalian species, including humans. Prenatal testosterone may contribute to these differences. The authors report the first attempt to correlate gender-typed play in a normative sample of humans with measurements of amniotic testosterone (aT). Testosterone was measured in the amniotic fluid of 53 children (31 boys and 22 girls). A strong sex difference was observed in aT and, at ages 4.75 to 5.8 years, on a modified version of the Child Game Participation Questionnaire. Hierarchical regression analyses on the entire group and within-sex correlations suggested that variations in aT did not contribute to individual differences in game participation as reported by the mother. A critique of explanations for this finding is presented.

Putting the five-factor model into context: evidence linking big five traits to narrative identity.

The study examined relationships between the Big Five personality traits and thematic content extracted from self-reports of life history data. One hundred and five "mature age" university students (M=30.1 years) completed the NEO PI-R trait measure, and the Personality Web Protocol. The protocol examines constituents of identity by asking participants to describe 24 key "attachments" from their life histories (significant events, people, places, objects, and possessions). Participants sorted these attachments into clusters and provided a self-descriptive label for each cluster (e.g., "adventurous self"). It was predicted that the thematic content of these cluster labels would be systematically related to Big Five trait scores (e.g., that labels referring to strength or positive emotions would be linked to Extraversion). The hypothesized links were obtained for each of the Big Five trait domains except Conscientiousness. Results are discussed with a view to broadening our understanding of the Five-Factor Model in relation to units of personality other than traits.

Fetal testosterone and empathy.

BACKGROUND: In animals, fetal testosterone (fT) plays a central role in organizing the brain and in later social behavior. In humans, exposure to atypical levels of prenatal androgens may result in masculine behavior and ability patterns. Normal inter-individual variation in fT levels has also been correlated with later sex-typed behavior. METHODS: In the current study, 38 children (24 male, 14 female), whose fT was analyzed in amniotic fluid, were followed up at age 4. They were asked to describe cartoons with 2 moving triangles whose interactions with each other suggested social relationships and psychological motivations. RESULTS: Females used more mental and affective state terms to describe the cartoons than males. fT was not associated with the frequency of mental or affective state terms. Females also used more intentional propositions than males. fT was negatively correlated with the frequency of intentional propositions, taking sex differences into account. fT was also negatively correlated with the frequency of intentional propositions when males were examined separately. Males used more neutral propositions than females. fT was directly correlated with the frequency of neutral propositions, taking sex differences into account. This relationship was not seen when males and females were examined separately. CONCLUSIONS: These findings implicate fT in human social development. The relevance of our findings to the 'extreme male brain' theory of autism is also discussed.

Foetal testosterone, social relationships, and restricted interests in children.

BACKGROUND: Sex-differences exist in some areas of human social behaviour. In animals, foetal testosterone (fT) plays a central role in organising the brain and in later social behaviour. fT has also been implicated in language development, eye-contact, and spatial ability in humans. METHODS: Fifty-eight children (35 male and 23 female), whose fT was analysed in amniotic fluid, were followed up at age 4. Their mothers completed the Children's Communication Checklist, a questionnaire assessing language, quality of social relationships and restricted interests. RESULTS: fT was negatively correlated to quality of social relationships, taking sex-differences into account. fT was also positively correlated with restricted interests in boys. CONCLUSIONS: These findings implicate fT in both social development and attentional focus. They may also have implications for understanding the sex ratio in autism.