[Psychoses in epilepsy--classification and EEG-studies (author's transl)].

It is necessary to classify the epileptic psychoses before starting a comparative study between psychopathological and electroencephalographic findings. The knowledge of the epileptic psychoses is at the moment too incomplete for a systematic order following aetiological or topic aspects. The traditionally system of epileptic psychoses distributes in chronic and episodic, phasic, especially circular, reversible and irreversible psychopathological manifestations. We differentiate psychotic states with or without disturbances of consciousness. Well-known in EEG studies of symptomatic and endogenic psychoses is, that in these psychoses the same clinical syndrom can be related to normal and to pathological electroencephalographic findings. This contradiction could often be explained when the activity of the psychoses was taken into consideration. The activity of the psychoses is to be determined by the duration, number, intensity and variability of the psychopathological symptoms. From his own investigations from 30 patients with schizophreniform epileptic psychoses, episode affective disorders and both depressive and manic psychoses, it could be shown, that normal EEGs are markedly infrequent. Most often they occur in subacute schizophreniform epileptic psychoses. The EEG of active and particularly of schizophreniform epileptic psychoses is most often characterized by simultaneous appearance of sharp waves, paroxysmal dysrhythmias and abnormal rhythm formations. Active schizophreniform psychoses correlate usually with abnormal rhythms. These abnormal rhythms ("parenrhythmien") diminish parallel with loss of activity of the psychotic process, are correspondingly seldom seen in subacute psychoses, and are not demonstrable in inactive psychoses. The experience of an alternating correspondence between epileptic psychoses and frequency of seizures could be confirmed.