Neuropsychological assessment in prepubertal patients with congenital adrenal hyperplasia: preliminary study

Individuals with congenital adrenal hyperplasia (CAH) provide a test population for the theory that elevated testosterone levels alter pre-/perinatal brain development.

Seven prepuberal girls with CAH and seven matched controls has been submitted to a neuropsychological evaluation. We measured abilities where gender differences repeatedly has been observed or that had earlier shown differences between CAH subjects and controls. The following cognitive functions were tested: general intelligence, attention, verbal and non-verbal abilities, cerebral dominance for verbal and non-verbal material, frontal functions, peripheral dominance and motor fluency. Since several animal studies shown hippocampal morphological changes induced by prolonged hydrocortisone exposure, we also investigated memory functions.

No differences were recorded between two groups on those abilities that are not sexually dimorphic. The mean general intelligence level of the patients was significantly lower than the controls', in agreement with previous studies. The verbal and non-verbal tasks revealed an age-related male-like pattern (i.e., verbal disadvantage) and an inversion of the hemispheric dominances. The latter observation was supported by a right-to-left shift of the peripheral dominances. The patients memory performances were all inferior to the controls'. The results are discussed in the light of possible hormonal influences.

Our main findings support the hypothesis that elevated pre-/perinatal androgen exposure can influence some cognitive pattern of specific sexual dimorphic abilities in prepubertal subjects.