This revision of the successful text draws on the latest research in all areas of the field, including biology and biochemistry, neurology, psychology, and sociology. Presenting the concepts of motivation and emotion as related aspects of the same general phenomena, it examines the basic biological and physiological systems underlying motivational and emotional responses, emphasizing how these interact with cognitive and other higher order processes. This background is applied to a series of specific types of motives and behavior patterns, such as aggression, sexuality, emotional expression, and competence. The author goes on to examine the interaction between cognitive and physiological factors, leading to a discussion of the central theme of the book: that increasingly complex social influences have, in the course of human evolution, liberated most human behavior from direct biological / physiological control. This thoroughly revised and updated edition includes coverage of studies of the human brain via radioactive elements, a section on the facial feedback hypothesis, and an expanded treatment of the implications of right-versus-left hemisphere research. Also provided are a critical review of psychosurgery and physiological control, including a discussion of the CIA's involvement in this area, an examination of the effect of erotic films on aggressive behavior, and more.