Abstract
Etiopathogenetic research gives rise to the suspicion that the classifications on hand pool heterogeneous disturbances under the heading of schizophrenia. This has drawn increasing attention to the necessity of identifying schizophrenic subsyndromes. Investigations using factor analysis revealed convincingly three major groups of schizophrenic symptoms: 1. a "negative factor", 2. a "psychoticism factor", comprising delusions and hallucinations and 3. a "disorganization syndrome" whose cardinal item is formal thought disorder. These studies have not yet furnished final results, but already opened insights enabling the conceptualization of syndrom-oriented therapies. The observation that the psychoticism symptomatology occurs in the frame of a "dynamic instability", based on a thymopsychic hyperreactivity, is in this regard especially important. In schizophrenic patients this hyperreactivity may be caused by secondary biological compensation mechanisms - such as perhaps an "up-regulation" of postsynaptic dopamine receptors. "Classic" neuroleptics can only correct the dynamic instability and thus eliminate psychoticism symptoms and reduce the accentuation of disorganization symptoms. They have, however, no influence upon negative symptomatology and can moreover aggravate "secondary" negative symptoms and especially impede cognitive functions. New "atypical" neuroleptics do not produce these side effects. They seem to have a reducing influence on negative symptoms and to improve cognitive functions. In each neuroleptic therapy a stepwise drug withdrawal should make clear whether or not a continous treatment is necessary. In the first case the needed efficacious dosis must be identified. The patients must learn to recognize relapse prodromes and to prevent the appearance of acute episodes through appropriate modifications of the medication. This strategy requires the combination with adequate psychotherapeutic methods enabling the patient to master persistent negative and disorganization symptoms in the best possible way.