TESTOSTERONE IMPROVES MAZE PERFORMANCE AND INDUCES DEVELOPMENT OF A MALE HIPPOCAMPUS IN FEMALES

In a combined behavioral and morphometric study, we observed a testosterone-related sexual dimorphism in the granule cell layer of the hippocampus of Sprague-Dawley rats that appears to be related to sex differences in spatial performance. This cell layer was larger and laterally asymmetrical in males. Neonatal testosterone treatment of females resulted in a more male-like hippocampus. These treated females also performed better than controls, and as well as males, on a spatial navigation task. In addition, a strong correlation between the size of granule cell layers and maze performace was detected.