Neurobiology of Schizophrenia: Electrophysiological indices

The objective of the WPA section on Psychoneurobiology is the promotion of the integration of findings from research fields such as neurophysiology, psychology, neuropsychology and psychiatry. This chapter focuses on the importance of electroencephalographic (EEG) studies for the section's objectives and especially for (a) the study of functional brain abnormalities related to liability to psychosis and schizophrenia pathophysiology and (b) characterization of schizophrenia psychopathological dimensions. The introduction will highlight the importance of EEG investigations in psychiatry, outlining a model of brain function, based on the notion of state-dependent information processing, and providing examples relevant to schizophrenia research. The second paragraph will summarize the current state of knowledge about resting state EEG connectivity in subjects with schizophrenia (SCZ) and draw some tentative conclusions about the possible links to the range of cognitive and behavioural abnormalities observed in these patients. The third paragraph will illustrate findings from event-related potential (ERP) studies of subjects at risk for psychosis who later develop schizophrenia-spectrum disorders. Some of the ERP parameters are proposed as biomarkers of the transition to psychosis and, if further validated, can be used to identify subjects for early interventions. The final paragraph of the chapter will summarize findings relevant to the characterization of the psychopathological dimensions of schizophrenia.