Schizophrenia is a chronic and disabling mental disorder characterized by distortions in thinking, perception, emotions, language, sense of self and behaviour. The oscillatory pattern of electrical activity generated by synchronized neuronal firing at rest might help in identifying the subjects of schizophrenia. Though various studies have tried to assess the underlying functional connectivity and its impairment in the patients of schizophrenia, the exact mechanism remains to be elucidated. The present study was conducted in the Department of Physiology in collaboration with the Department of Psychiatry, S. M. S. Medical College, Jaipur (Rajasthan). Twenty-one newly diagnosed schizophrenia patients aged 18-40 years from Psychiatry OPD were recruited as cases and an equal no. of age matched healthy subjects were recruited as controls from the accompanying attendants of patients. The inter and intra-hemispheric coherence among various brain areas was evaluated in delta, theta, alpha 1, alpha 2, beta 1, beta 2and gamma frequency bands. The resting EEG coherence was significantly reduced between various electrode pairs in schizophrenia patients in delta (C3-P3, P3-T3, F3-P3&P3-P4), theta (C3-P3, P3-T3, F3-P3&P3-P4), alpha-1(C3-P3, P3-T3& C4-T4), alpha-2 (C3-P3, P3-T3&C4-T4) and gamma (C3-P3& P3-P4) frequency bands as compared to healthy controls. The schizophrenia patients exhibit functional dysconnectivity in frontal, central, parietal and temporal regions that might underlie the impaired thought process in schizophrenia patients, especially in the left hemisphere.

Keywords: Schizophrenia, Electroencephalogram (EEG), Coherence, Functional Connectivity, Inter-hemispheric and Intra-hemispheric.

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Ashok Kumar Kumawat

Senior Professor, Department of Physiology, S. M. S. Medical College, Jaipur (Rajasthan)