Quantitative electroencephalogram (QEEG) spectrum analysis of patients with schizoaffective disorder compared to normal subjects

Objective: The aim of this study was to achieve a better understanding of schizoaffective disorder. Therefore,we obtained electroencephalogram (EEG) signals from patients with schizoaffective disorder and analyzed them in comparison to normal subjects. Method: Forty patients with schizoaffective disorder and 40 normal subjects were selected randomly and their electroencephalogram signals were recorded based on 10-20 international system by 23 electrodes in open- and closed-eyes while they were sitting on a chair comfortably. After pre-processing for noise removal and artifact reduction,we took 60-second segments from each recorded signals. Then,the absolute and relative powers of these segments were evaluated in all channels and in 4 frequency bands (i.e.,delta,theta,alpha and beta waves). Finally,Data were analyzed by independent t-test using SPSS software. Results: A significant decrease in relative power in the alpha band,a significant decrease in power spectra in the alpha band and a significant increase in power spectra in the beta band were found in patients compared to normal subjects (P 0.05). The predominant wave in the centro-parietal region was the beta wave in patients,but it was the alpha band in normal subjects (P = 0.048). Also,the predominant wave of the occipital region in patients was the delta wave,while it was the alpha wave in normal subjects (P = 0.038). Conclusion: Considering the findings,particularly based on the significant decrease of the alpha waves in schizoaffective patients,it can be concluded that schizoaffective disorder can be seen in schizophrenia spectrum.