Are men and women really different? Or is this a result of our social stereotypes. We've all heard that "Men are from Mars and women are from Venus," but do physiological differences account for the perceived emotional, psychological and intellectual differences (if these do exist and are not a figment of our imaginations). Are boys really better in math (and should girls just give up)? Will men just never understand women (and will the football game always be beyond the female understanding)? In studying humans, we must first understand the physiology that may cause the sexual dimorphism and then we may be able to relate these differences to the actual populations under study, to draw more conclusive, science-based arguments. There is a clear correlation between the development of the brain and more complex tool use, development of language and art, and social hierarchies. Considering that physical differences gave rise to the more complex populations, analysis of brain differences among the modern populations may yield some interesting data about the differences between current humans.

Scientific studies have focused on specific areas of the brain, using fMRI, PET and CT scans to distinguish between the variable regions and compare these regions among the subjects. Brain analysis is also used to study handedness, sexual orientation, diseases (particularly those affecting the brain), speech ability, skills and to find correlation between brain and social status. Certain areas of the brain have been found to directly correlate between sex and the difference in actions between men and women, and have led to a greater understanding of how the brain is organized as well as how the differences in brain structure may effect human function.