CONTENTS: List of Contributors. Acknowledgements. Preface. Genetic and immunological factors in affective disorders and schizophrenia (J. Mendlewicz and S. Sevy). Two syndromes in schizophrenia and the viral hypothesis (T.J. Crow, G.R. Taylor and D.A.J. Tyrrell). Brain noradrenaline and schizophrenia (O. Hornykiewicz). Dopamine agonists in the treatment of schizophrenia (M. Del Zompo, A. Bocchetta, M.P. Piccardi and G.U. Corsini). Nutrition and psychoses (A. Wunderink, L. Pepplinkhuizen and J. Bruinvels). Indoleamines in depression and suicide (H.M. van Praag). Anxiety and the benzodiazepine receptor (T.R. Norman and G.D. Burrows). Cholenergic dysfunction in Alzheimer disease: cause or effect? (D.A. Plotkin and L.F. Jarvik). Immunocytochemical localization of vasopressin in the human brain; its possible consequences for therapeutic strategies in aging and dementia (D.F. Swaab, E. Fliers and W.A. van Gool). Neurons with multiple messengers - distribution and possible functional significance (T. HÖkfelt, G. Fried, S. Hansen, V. Holets, J.M. Lundberg and L. Skirboll). Synthesis, function and degradation of catecholamine neurotransmitters (C.W. Abell). Pituitary regulation in endogenous depression (E.A. Young, S.J. Watson and H. Akil). Post-mortem neurochemistry of human brain (M.N. Rossor). Neuropeptides and cognitive disorders (J. Jolles). Pituitary proopiomelanocortin peptides in mental disorders (F. Brambilla, F. Petraglia, F. Facchinetti, M. Maggioni and A.R. Genazzani). Opioid peptides in the cerebrospinal fluid of psychiatric patients (L. Terenius and F. Nyberg). Antipsychotic action of *g-type endorphins: animal and human studies (J.M. van Ree, W.M.A. Verhoeven, F.H.J. Claas and D. de Wied). Cholecystokinin and schizophrenia (N.P.V. Nair, S. Lal and D.M. Bloom). Animal models in psychiatric research (S. Matthysse). Subject index.