8 - Gender Differences in the Functional Organization of the Brain

Abstract

The existence of sex differences in brain anatomy and physiology has implications for understanding the neural organization of behavior in healthy people and its disruption in illness. This chapter reviews the available evidence for gender differences in behavior that may relate to differences in brain anatomy and physiology. Gender differences in cognition have been well documented with standardized measures. Women perform better on verbal and memory tasks, whereas men excel in spatial tasks. Sex-related differences in behavior have been observed across species and are increasingly being linked to sex differences in neurobiologic substrates. Efforts to relate gender differences in cognition to neurobiologic substrates have followed three main avenues: correlation of cognitive performance with hormonal state; examination of neuroanatomic measures in structural imaging and postmortem studies; and examination of neurophysiologic measures using functional imaging. Gender differences are also observed in affect and emotion processing. Women perform better in speeded emotion recognition tasks and in tasks requiting facial expression of emotions. Sex differences in brain anatomy have been increasingly documented with methods for morphometric analysis of MRI data.