ABSTRACT
Sex differences in a variety of spatial learning tasks had been demonstrated in nonhuman species, suggesting sexual differentiation in spatial functions is not a uniquely human phenomenon. Two of the most important sources of evidence for testing the role of early life hormones in sexual differentiation of cognitive function are people with congenital adrenal hyperplasia (CAH) and people born of pregnancies in which the mothers ingested the synthetic estrogen diethylstilbestrol (DES) during gestation. An important corollary source of information about the sexual differentiation of spatial functions comes from studies of people exposed to the synthetic estrogen DES during gestation. DES is a nonsteroidal estrogen that was widely prescribed for the prevention of miscarriage from the 1940s to the early 1970s. The hypothesis that there is an organizational effect of early androgens on spatial abilities in humans is supported by evidence from people with CAH and by the work by Grimshaw incorporating a direct assay of testosterone in amniotic fluid.
