Sex Differences in the Human Brain

Abstract

The chapter starts with how ideology enters into studies of sex differences. Next, Stuart Richie claims that he has completed the largest study of sex differences to date. His findings come next. The fact that male brains are larger and how this is irrelevant follows with a statement of what brain parts are important in sex-differences studies. Hard-wired differences in brain parts come next as well as socialization differences. A summary statement of this by Goldman is presented. Sex differences in toys chosen by boys and girls between 9 and 7 months old follows. Other differences between males and females are presented. Sex differences in mental health come next. The fact that certain brain parts differ in males and females and their behavioral consequences follows. Consequences of differences in the amygdalae are detailed. A large study by Roberta Jenkins on the sex-related asymmetry of important brain structures follows. Genetic differences in the male and female brains are then presented. Asymmetry of subcortical brain structures that are most likely to influence cognition follows. Next, a vulnerability to brain disorders due to genetic variation is presented. Sex-based differences related to mating, aggression, and parenting are detailed. Nirao Shah refers to a new “sea change” from the belief that sex differences are due to culture to brain-differences. This is followed by an overview by Richie. A summarizing conclusion ends the chapter.