Electrophysiological subtypes of psychotic states

Objective: This research sought neurobiological features common to psychotic states displayed by patients with di. erent clinical diagnoses. Method: Cluster analysis with quantitative electroencephalographic (QEEG) variables was used to subtype drug-naive, non-medicated, and medicated schizophrenic, depressed and alcoholic patients with psychotic symptoms, from the USA and Germany. QEEG source localization brain images were computed for each cluster. Results: Psychotic patients with schizophrenia, depression and alcoholism, and drug-naive schizophrenic patients, were distributed among six clusters. QEEG images revealed one set of brain regions di. erentially upregulated in each cluster and another group of structures downregulated in the same way in every cluster. Conclusion: Subtypes previously found among 94 schizophrenic patients were replicated in a sample of 390 non-schizophrenic as well as schizophrenic psychotics, and displayed common neurobiological abnormalities. Collaborative longitudinal studies using these economical methods might improve di. erential understanding and treatment of patients based upon these features rather than clinical symptoms.