Cognitive abilities in women with complete androgen insensitivity syndrome and women with gonadal dysgenesis

Background: Many questions regarding the mechanisms behind sex differences in cognitive abilities are still unanswered. On a group level, men typically outperform women on certain spatial tasks, whereas women perform better on certain tests of memory and verbal ability. The prevailing theories concerning the biological predispositions for these and other differences in behaviour and brain function focus on early and prolonged exposure to sex hormones. There is, however, evidence of direct effects of sex chromosomes on sex-typical behaviour in other species. Objectives: To study the influence of sex hormones and sex chromosomes on cognition in women with Complete androgen insensitivity (CAIS) and Gonadal dysgenesis (GD). Methods: Eighteen women with CAIS, 6 women with 46,XYGD, and 7 women with 46,XXGD were compared with age-matched male and female controls on tests of spatial and verbal abilities, memory functions, and emotion recognition. Results: Women with CAIS, XYGD, and XXGD performed similar to female controls on cognitive tasks. However, on a test of emotion recognition, women with XXGD outperformed the other groups, whereas women with CAIS and XYGD performed similar to male controls. Conclusion: Our results support theories of androgen effects on cognitive abilities and suggest that factors related to sex chromosomes may influence emotion recognition. Implications of an atypical sex hormone situation and sex chromosome variation are discussed.