Effects of sex, free testosterone, and androgen receptor cag repeat number on spatial cognition and virtual navigation performance

EFECTS OF SEX, FREE TESTOSTERONE, AND ANDROGEN RECEPTOR CAGREPEAT NUMBER ON SPATIAL COGNITION AND VIRTUAL NAVIGATIONPERFORMANCEbyNICOLE T. NOWAKMay 2012Advisor: Dr. Scott D. MoffatMajor: Psychology (Behavioral and Cognitive Neuroscience)Degree: Doctor of PhilosophyThe male advantage typically found on some measures of spatial cognition (e.g.,mental rotations) has been approached for three decades from the perspective thatandrogens contribute to this sex difference. To date, evidence to support the notion thatandrogens affect spatial cognition in healthy young individuals is balanced by evidenceto the contrary. The present study sought to clarify the association between androgensand spatial performance by extending our measurements of androgenicity to includeboth a measure of circulating testosterone as well as a receptor-specific marker.The aims of this dissertation were to assess the effects of sex, testosterone, andandrogen receptor CAG repeat number on spatial performance and experience in agroup of healthy young men and women. The hypothesis that men would outperformwomen on measures of spatial skills was largely supported, with some caveats.Predictions that testosterone would relate directly to spatial performance were notconfirmed; however, results indicate that number of CAG repeats may have a directimpact on cognition, and may modify the relationship between testosterone and spatial