Cortical thickness, or the tissue volume and tissue composition of the cerebrum, has long been explored as a possible explanation for behavioral differences in men and women. Magnetic Resource Image (MRI) studies have shown that gray matter, white matter, and brain size are smaller in women than men, even after controlling for body size. When both gray and white matter normalize, adult men have a greater proportion of white matter, whereas women demonstrate a greater proportion of gray matter (Allen et al., 2003; Gur et al., 1999). Women also demonstrate significantly greater global and regional cortical thickness, while no significant thickening is observed in men. This significant cortical thickening in women is localized in anatomical regions consistent with studies that support sexual dimorphism (Kiho et al., 2006). During childhood and adolescence, white matter volume increases faster in boys than in girls. When examining specific brain regions, greater diffusivity was found in the corticospinal tract and the frontal white matter in the right hemisphere for boys, whereas greater diffusivity was found in the occipital-parietal regions and the most superior aspect of the corticospinal tracts in the right hemisphere in girls (Rabinowicz, Dean, Petetot, & de Courten-Myers, 1999). Coincidently, girls show a greater organization in the right hemisphere compared to the left hemisphere for boys. These differences in brain matter and diffusivity may indicate differing develop