[How does the schizophrenic nuclear syndrome arise? Results of the Bonn transition series study and Anglo-American models--a comparison].

The value of neurobiological theories of schizophrenia depends in the long run on their usefulness when the genesis of diagnostically relevant features is to be made plausible. That is why in recent Anglo-American research on schizophrenia more and more subtly differentiated models have been developed to explain even highly complex psychotic changes of experiences in terms of neurobiologically founded cognitive deficits. Empirical testing, however, was hardly possible, since there did not exist any studies dealing with the hypothesized connections between psychosis and psychological deficit. This situation has now changed with the Bonn study of sequences of transition from experiences of deficiency to first rank symptoms. Its overall result permits an empirically based assessment of the genesis of all elements constituting the schizophrenic nuclear syndrome according to the "Present State Examination". In the present contribution the results concerning the genesis of thought insertion, -withdrawal, -broadcasting, and first rank verbal hallucinations are singled out and compared to the corresponding Anglo-American models. The summary results in a sweeping confirmation, yet it also reveals the insufficiency of a simply "rationalistic" view of the symptom genesis.