Already the subject of considerable pre-publication discussion, this magisterial work by one of the nation's leading neuroscientists presents a radically new view of the function of the brain and nervous system. Its central idea is that the nervous system in each individual operates as a selective system resembling natural selection in evolution, but operating by different mechanisms. By providing a fundamental neural basis for categorization of the things of this world it unifies perception, action, and learning. The theory also completely revises our view of memory, which it considers to be a dynamic process of recategorization rather than a replicative store of attributes. This has deep implications for the interpretation of various psychological states from attention to dreaming. Neural Darwinism ranges over many disciplines, focusing on key problems in developmental and evolutionary biology, anatomy, physiology, ethology, and psychology. This book should therefore prove indispensable to advanced undergraduate and graduate students in these fields, to students of medicine, and to those in the social sciences concerned with the relation of behavior to biology. Beyond that, this far-ranging theory of brain function is bound to stimulate renewed discussions of such philosophical issues as the mind-body problem, the origins of knowledge, and the perceptual basis of language.

This pioneering study looks at the effects of prenatal testosterone on postnatal development and behavior. Hormonal effects on behavior have long been studied in animals; the unique contribution of this book is to suggest a connection between human fetal hormones and later behavior. It details for the first time testosterone's effect on social and language development, opening a new avenue of research for cognitive neuroscience.The authors look at samples of amniotic fluid taken during amniocentesis at 16 weeks' gestation, and relate the fetal level of testosterone (which is present in fetuses of both sexes, although in different quantities) to behavior at ages 1, 2, and 4 years. They argue that the amniotic fluid provides a window into the child's past -- a chemical record of that child's time in the womb -- that allows informed prediction about the child's future brain, mind, and behavior. This is not the retrospective speculation of psychoanalysis, they point out, but an opportunity to study development prospectively and trace developmental precursors and causes of later cognition.The study suggests that prenatal levels of testosterone affect a range of later behaviors in children, from the inclination to make eye contact with others to the size of the vocabulary. It also suggests that prenatal testosterone level may be related to the development of typically "masculine" and "feminine" behaviors. The study's ongoing research explores whether fetal testosterone has any link with the risk of developing autism. Connecting endocrinology and psychology, the authors propose that there is a biological component to behaviors often thought to be produced by the social environment.