William James famously described the infant's perceptual world as a “blooming, buzzing confusion,” and a century later, the same words might apply to the field of psychology. With historical roots in both physiology and philosophy, psychology has proliferated into a multitude of subdisciplines served by specialized journals and conferences. In the face of such diversity, a few conferences and publications hold fast to the goal of presenting psychological research across the broad spectrum of subdisciplines. This edited volume, together with its companion volume (Vol. 1: Social, Personal, and Cultural Aspects), represents the proceedings of the XXVIth International Congress of Psychology, convened in Montreal in 1996, with the goal of providing “the latest research developments in psychology from around the world.” The volume contains quality reviews by an international roster of authors, and demonstrates at once both the sophisticated “blooming and buzzing” of many individual research programs in cognitive and biological psychology, and a largely untapped potential for the development of unifying themes and principles across the discipline.