Interest in biological psychology, the study of psychological processes in terms of biological functions, has grown dramatically in the last few years. Not only does it play a key role in the study of artificial intelligence, but the drive to find physical solutions to the 'addictions' and 'psychiatric disorders' which afflict modern society is increasing in momentum. A major obstacle to understanding dialogue in the field has always been the terminology. The terms are drawn from a variety of non-psychological sources such as clinical medicine, psychiatry and neuroscience, as well as specialist areas of psychology such as ethology, learning theory and psychophysics. In the past the only source of help has often been a medical dictionary in which terms are defined in language which itself requires definition for the non-specialist. For the first time, a distinguished international team of contributors has now drawn these terms together and defined them both in terms of their physical properties and their behavioural significance. The result creates a vital link between the various disciplines active in the field, enabling social and biological scientists to work together more productively and read each other's literature with a greater degree of understanding. The Dictionary will prove an invaluable source of reference for undergraduates in psychology wrestling with the fundamentals of brain physiology, anatomy and chemistry, as well as researchers and practitioners in the neurosciences, psychiatry and the professions allied to medicine. It is an essential resource both for teaching and for independent study, reliable for fact-checking and a solid starting point for wider exploration. Entries include: 5-hydroxyindoleactic acid (5-HIAA), anorexia, computational vision, agnosia, crack babies, lateral hypothalamic syndrome, narcolepsy, peyote, post-traumatic stress disorder, precollicular-postmammillary transection, pleasure, xanthines. Editorial Consultants: Marlene Behrmann Carnegie-Mellon University, USA;Ian J.Reid University of Dundee, UK; Howard C. Eichenbaum Boston University, USA; Barry Everitt University