New techniques for peering into the human brain have changed the nature of the questions being asked and the kinds of answers that can be expected. Although it is a comprehensive and up-to-date synthesis of scientific theory and research into how, why, when, and to what extent females and males differ in intellectual abilities, it conveys complex ideas and interrelationships among variables in an engrossing and understandable manner, bridging the gap between sensationalized 'pop' literature and highly technical scientific journals. In contrast, among the area measurements of the corpus callosum and 22 subdivisions, only 1 exhibited a significant sex difference, which would be expected by chance. There have been surprising new findings on the influence of sex hormones on cognitive abilities across the life span, as well as an increasing number of studies examining how attention paid to category variables such as one's sex, race, or age affects unconscious and automatic cognitive processes. Halpern's thought-provoking perspectives on this controversial topic will be of interest to students and professionals alike. However, sex differences in bulbosity did not reach significance in children aged yr. This new edition reflects the explosion of theories and research in the area over the past several years. She provides a comprehensive context for understanding the theories and research on this controversial topic. Written in a clear, engaging style, this new edition takes a refreshing look at the science and politics of cognitive sex differences. Abstract The sexual dimorphism of the corpus callosum has remained controversial since the original report by de Lacoste-Utamsing and Holloway in , for several reasons: These anatomical sex differences could, in part, underlie gender-related differences in behavior and neuropsychological function. In adults, the midsagittal surface area of the cerebral cortex decreased significantly with age in women but not in men. It is a beautifully written book by a master teacher who really cares about presenting a clear and honest picture of contemporary psychology's most politicized topic. The area of the corpora callosa increased significantly with age in children and decreased significantly with age in adults. While we observed a dramatic sex difference in the shape of the corpus callosum, there was no conclusive evidence of sexual dimorphism in the area of the corpus callosum or its subdivisions.