White P M, Yee C M
Department of Psychology, University of California, Los Angeles 90095-1563, USA.
Psychophysiology. 1997 Nov;34(6):703-11. doi: 10.1111/j.1469-8986.1997.tb02145.x.
The decline in amplitude of the P50 component of the event-related potential to the second of paired clicks has been suggested as a measure of preattentional gating. Two experiments were conducted to assess the effects of attention and a psychological stressor on P50. Experiment 1 included two choice reaction time tasks designed to direct attention selectively to the first or second click in each pair. Results suggest that the N100 component was responsive to attentional manipulations, whereas P50 was not affected. Experiment 2 examined the impact of a brief psychological stressor on the P50 response. Parallel mental arithmetic tasks were administered silently and orally. Self-report and measures of autonomic activity were used to assess the level of stress occurring during the performance of the mental arithmetic tasks. Results indicate that P50 suppression was sensitive to the acute stressor, the oral mental arithmetic task. Implications of these findings for studies of P50 suppression in schizophrenia are discussed.
事件相关电位对成对点击中的第二个点击的P50成分的波幅下降，已被提议作为一种前注意门控的测量方法。进行了两项实验，以评估注意力和心理应激源对P50的影响。实验1包括两个选择反应时任务，旨在将注意力选择性地引导至每对点击中的第一个或第二个点击。结果表明，N100成分对注意力操作有反应，而P50不受影响。实验2考察了短暂心理应激源对P50反应的影响。同时进行了无声和有声的并行心算任务。使用自我报告和自主活动测量来评估心算任务执行过程中出现的应激水平。结果表明，P50抑制对急性应激源（有声心算任务）敏感。讨论了这些发现对精神分裂症中P50抑制研究的意义。
