中文摘要：

目的探讨听觉感觉门控电位P50对精神分裂症的诊断价值。方法共入组56例患者（患者组）和22名正常对照（对照组）。患者符合美国精神障碍诊断与统计手册第4版（DSM-IV）的精神分裂症诊断标准。采用听觉条件（S1）-测试刺激（S2）范式检测P50电位,计算S2与S1波幅的比值即P50比值。使用阳性与阴性综合征量表（PANSS）评定患者的精神症状。结果患者组P50比值（89.7±57.1）高于对照组（47.2±26.4）,差异有统计学意义（t=2.97,P〈0.01）。患者组P50比值与PANSS总分和病程之间无相关性（r值分别为0.123、0.119）。P50比值的ROC曲线下面积（AUC）=0.743。以34为临界值,灵敏度和特异度分别为96.4%和45.5%;以50为临界值,灵敏度和特异度分别为80.4%和50.0%。结论精神分裂症患者存在感觉门控障碍,P50比值与其病情和病程无关,P50比值在精神分裂症有中等诊断价值。

英文摘要：

Objective：To explore the diagnostic value of auditory sensory gating P50 in schizophrenia.Methods：A total of 56 patients with schizophrenia and 22 normal controls were enrolled from January 2008 to December 2009.All patients met Diagnostic and Statistical Manual of Mental Disorders 4th edition （DSM-IV） criteria for schizophrenia.Conditions （S1）-test （S2） stimulus paradigm was used to detect the P50 auditory evoked potential in subjects.P50 ratio was defined as the ratio of P50 amplitudes for S2 and S1 （S2/S1）.The efficacy was evaluated by positive and negative syndrome scale （PANSS）.Results：Schizophrenia patients had significant higher P50 ratio（89.7±57.1） than control groups（47.2±26.4）（t=2.97,P0.01）.There was no relationship between P50 ratio and PANSS total score or duration of illness in schizophrenia patients.The area under ROC curve of P50 ratio was 0.743.The sensitivity and specificity were 96.4% and 45.5%,respectively,when 34 was used as a cut-off point,or they were 80.4% and 50.0%,respectively,when 50 was used as a cut-off point.Conclusion：Schizophrenia patients have sensory gating dysfunction.There is no relationship between sensory gating and severity of clinical symptoms or duration of illness in schizophrenia patients.P50 ratio has moderate value in the diagnosis of schizophrenia.