[A third kind of psychosis. Analysis of the literature]

Undoubtedly there exist atypical functional psychoses which differ significantly from schizophrenia and manic depressive illness. However, the atypical psychoses are conceptualized in various ways and they represent a quite heterogenous group of disorders. Regarding their main characteristics, they can be classified as 1. schizoaffective psychoses with a predominantly atypical phenomenology, 2. cycloid psychoses with a predominantly atypical course, and 3. psychogenic psychoses with a predominantly atypical etiology. For heuristic and clinical reasons it is recommendable: 1. to separate atypical psychoses from schizophrenia and manic depressive disorder and 2. to handle each of the three depicted forms of atypical psychoses as a different and independent group, regardless of possible overlaps.