Application of N100, P300 and QEEG as a Biological Marker in Patients with Schizophrenia

Lim, Yongsoo; Lee, Seung Hwan; Hong, Suk In

Abstract

OBJECTIVE
This study was carried out to investigate the clinical availability of event related potential (ERP) P300, N100 and QEEG as biological markers in schizophrenia (SPR) patients.
METHODS
The 23 SPR patients who met Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) criteria of SPR and age and sex matched 23 normal controls (NC) were recruited. Positive and Negative Syndrome Scale (PANSS) was used to evaluate the clinical symptoms. The three electrodes (Cz, CPz, Pz) were used to measure the amplitude and latency of each ERP components. The qEEG was analyzed by the ranges of Hz: delta (1-3 Hz), theta (4-7 Hz), alpha (8-12 Hz), beta (13-30 Hz) and gamma (30-50 Hz).
RESULTS
P300 amplitudes of SPR patients were reduced across Cz, CPz and Pz (F=5.81, p<0.05). There was no difference in P300 latency, N100 amplitude and N100 latency between SPR and NC. P300 amplitudes were not influenced by demographic characteristics and PANSS scores in SPR patients. The PANSS positive, negative, general subscale scores were positively correlated with N100 latency at Cz, CPz. SPR patients showed significantly decreased alpha activity (SPR vs. NC=24.44+/-6.98% vs. 29.55+/-6.74%, p<0.05) and increased gamma activity (SPR vs. NC=19.48+/-5.47% vs. 16.42+/-4.69%, p<0.05) compared with those of NC.
CONCLUSION
The results suggest that the amplitude of P300 and alpha activity can be considered as a biological marker of SPR. And there is a possibility that the latency of N100 may reflect symptom severity of schizophrenia patients.