Comparison of Frontal Area's Beta Waves of Schizophrenic Patients with Negative and Positive Symptoms with a Healthy Group

Frontal lobe, especially prefrontal areas dysfunction, is one of the assumptions in the pathogenesis of schizophrenia. Consistent with this hypothesis, a deficit of prefrontal cortex oligodendrocytes was reported in schizophrenic patients. Quantitative Electroencephalography (Q-EEG) studies in these patients indicated that there is an increased in beta, delta and theta waves but a lack of alpha activity. The objective of this study was to study the frontal lobe beta activity in symptomatic and asymptomatic schizophrenic patients and normal individuals. Thirty patients diagnosed with schizophrenia (diagnosed by DSM-IV-TR criteria), and 30 normal individuals entered this study. Patients group was divided in to symptomatic and asymptomatic subgroups by Assessment of Negative Symptoms (SANS) and Scale for Assessment of Positive Symptoms (SAPS) tests. The results of SANS and SAPS indicated that 14 patients had negative and 16 patients had positive symptoms. Q-EEGs of patients and control groups were obtained from 8 areas of frontal lobes and the results were compared. Results indicated that there were significantly differences between the groups in 4 areas of frontals waves (Fz, Fp2, Fpz, Fp1). Activity of beta waves, in patient groups was generally increased. Moreover in patients with positive symptoms, activity of beta was higher than in patients with negative symptoms. It is concluded that obtained beta waves from different areas of frontal lobes, in addition to borderline of frontal lobes, differed significantly from obtained beta waves from the same areas of frontal lobes in normal individuals.