Evolution of the American concept of schizoaffective psychosis.

A brief survey is given of the evolution of the concept of schizoaffective psychosis in the United States. The following phases are singled out: a first, 'prehistorical', one including description of 'mixed' psychotic syndromes regarded as subtypes of manic-depressive psychosis; a second, which covers the subsequent 30 years, in which the concept of schizoaffective psychosis is gradually included under the heading of schizophrenia, in accordance with the broad Bleulerian concept of this illness prevailing in those years; a third one, in which, under the influence of a number of factors, schizoaffective psychosis is shifted from the schizophrenic to the affective area, and even good-prognosis schizophrenia and DSM III schizophreniform disorder (a syndrome characterized by the same clinical picture of schizophrenia, but which lasts less than 6 months) are regarded as variants of affective illness. It is emphasized that the history of the evolution of the American concept of schizoaffective psychosis is, indeed, the history of the vicissitudes of the American conceptions of schizophrenia and manic-depressive psychosis.