[Subsyndromes in chronic schizophrenia. The heterogeniety of schizophrenic psychoses]

Recent psychopathological studies consistently identified a delusional, a negative, and a disorganised subsyndrome in chronic schizophrenia. Neuropsychological studies found the delusional sub-syndrome to be associated with an impaired delayed recognition, while the negative subsyndrome showed a marked deficit in delayed recall. In addition, the delusional and the negative subsyndromes shared procedural memory changes. The disorganised subsyndrome was associated with neurological soft signs and a poor working memory performance. Following neuroimaging studies, the delusional subsyndrome showed a significantly reduced hippocampal activity, while the asthenic sub-syndrome presented with a pronounced hypofrontality and significantly decreased activity in the corpus callosum. At the same time, both subsyndromes were associated with a decreased activity in the anterior cingulum and medial frontal cortex. The disorganised subsyndrome corresponded with an increased activity in the parietal cortex and motor strip. When compared with the healthy controls, these findings were not specific for the respective subsyndrome, since they were observed among all schizophrenics, but to a different extent. It is suggested that the subsyndromes of chronic schizophrenia represent psychopathological dimensions which may co-occur in the individual patient.