Clementz B A, Geyer M A, Braff D L
Department of Psychology, University of California, San Diego 92093-0109, USA.
Biol Psychiatry. 1997 May 15;41(10):1035-44. doi: 10.1016/S0006-3223(96)00208-9.
The present report investigated the relationship between P50 suppression and habituation among 20 schizophrenia and 20 normal comparison subjects. Subjects were presented with clicks delivered over headphones in a S1-S2 paradigm (clicks were separated by 500 msec; average intertrial interval was 8 sec). There were 60 total trials; the data were analyzed separately for the first and second 30 trials. The groups did not differ either on the number of usable trials or on the morphology of their P50 responses. Consistent with previous reports, schizophrenia patients demonstrated deficient P50 suppression. The overall suppression effect was not due to a group difference on S1 P50 amplitudes, but was associated with schizophrenia patients having smaller S1-S2 P50 amplitude difference scores than normal comparison subjects. Furthermore, the suppression effect appears to be more pronounced during the first than during the second block of trials. Thus, it may be important to evaluate changes in P50 responses over time among schizophrenia and normal comparison subjects.
本报告调查了20名精神分裂症患者和20名正常对照受试者中P50抑制与习惯化之间的关系。受试者在S1-S2范式下通过耳机听到点击声（点击声间隔500毫秒；平均试验间隔为8秒）。总共有60次试验；数据分别对前30次试验和后30次试验进行分析。两组在可用试验次数或其P50反应的形态上均无差异。与先前报告一致，精神分裂症患者表现出P50抑制缺陷。总体抑制效应并非由于两组在S1 P50振幅上的差异，而是与精神分裂症患者的S1-S2 P50振幅差异得分低于正常对照受试者有关。此外，抑制效应在试验的第一组中似乎比第二组中更明显。因此，评估精神分裂症患者和正常对照受试者中P50反应随时间的变化可能很重要。
