To Investigate Some Event-Related Potentials In Schizophrenia

Objective:To investigate some components of Event-Related Potentials p300 and Sensory Gating Event-Related Potentials p50 in Schizophrenia Patients as to provide a basis for clinic diagnosis.Method:Using the NihonKohden EEG evoked potential equipment of Japan to record the event-related potentials auditory evoked p300 and sensory Gating event-related potentials p50 amplitude ratios (S2/S1)% of the patients with first-episode schizophrenia (n=36 antipsychotics-naive),chronic schizophrenia (n=33 only take atypical antipsychotics),chronic patients (n=14 antipsychotics-naive/stop taking any antipsychotics at least 6 months) and 42 control subjects at Cz electrodes.Resulte:1.All 3 groups of patient show the reduced N1,P3b amplitude obviously (P<0.05) and delayed N2,P3a,P3b latency compared with the cotrol subjects.2. Reduced N2 amplitude only happens in patients of first-episode compared with the control subjects.3. Compared with normal subjects patients of frist-epsode schizophrenia and chronic schizophrenia using drug show impaired P50 ratios with obvious difference (p<0.05). However patients of chronic schizophrenia using no drug show P50 amplitude ratio with little difference from that of control groups (p>0.05).Conclusion:1. Schizophrenia have defects throughout almost all the cognitively processing.2. All patient groups show reduced N1, P3b amplitude, delayed N2, P3a, P3b latency unaffected by drugs and duration of diseases which may be the trait marker of schizophrenis.3. Amplitude reduction of N1, N2,P3b, latency delay of N2, P3a, P3b and impaired p50 amplitude ratios appear in the first-episode schizophrenia, thus those index can be used for early diagnosis and screens of schizophrenia.4.The reduction of amplitude of N2 only happens in the first-episode schizophrenia. It needs future study that amplitude of N2 is a index more sensitive than early affected indicators.5. Identification of the Event-Related Potentials p300 and Sensory Gating Event-Related Potentials p50 as the trait marker still need longitudinal further study.