Spatial function in adolescents and young adults with congenital adrenal hyperplasia: clinical phenotype and implications for the androgen hypothesis.

Females with the classic form of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency are said to perform better than unaffected female controls on tests of mental rotation or other visuospatial abilities, but findings are conflicting. We studied 31 adolescents and young adults with CAH and 19 unaffected sibling controls, who were given standardized spatial tests and tests of other sexually differentiated cognitive functions (verbal fluency, perceptual speed). The possible role of CAH subtype (salt-wasting or simple-virilizing) was evaluated. Only females with the more severe, salt-wasting form of CAH, but not females with the simple-virilizing form, performed significantly better than sex-matched sibling controls on measures of mental rotation. Subtype differences were not significant for verbal fluency or perceptual speed. Severity of prenatal genital virilization, but not postnatal age when medication was started, predicted accuracy on the Mental Rotations Test. Results are consistent with the possibility of an organizational effect of androgens in the central nervous system that impacts the development of spatial abilities. Implications for the timing of the hypothetical critical period are discussed.