The human brain is the inner universe through which all external events are perceived. That fact alone should ensure that neuroscience will eventually receive top priority in the list of human endeavors. The brain represents the pinnacle of sophistication in the realm of living systems. Yet it is an imperfect organ, whose failures in disease processes lead to the occupation of more than half of all hospital beds and whose variable performance in the healthy state contributes in undetermined degree to the world's social problems. Every significant advance in or understanding of the brain has yielded enormous practical dividends. There is every reason to believe the future holds even greater promise. In the preface to our first edition, we drew attention to the establishment of graduate programs in dozens of universities around the world and the emergence of numerous international journals devoted to interdisciplinary work on the brain. The discoveries that have flowed from this activity have required extensive updating of the details of this book, which is a testimony to the fruitfulness of neuroscience research. Yet the basics remain the same. It is more important than ever that the neuroscientist be presented with the fundamental subdisciplines that together make up the total of brain research in an integrated manner.