Ritter W, Sussman E, Deacon D, Cowan N, Vaughan H G
Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Psychophysiology. 1999 Nov;36(6):835-8.
Event-related potentials (ERPs) were recorded during a go/no-go reaction time (RT) task in which subjects responded to rare target tones and withheld response to frequent tones. In a predictable condition, a rare visual stimulus signalled the impending occurrence of a rare tone, whereas a frequent visual stimulus signalled that a frequent tone would be presented. The rare visual stimuli elicited P3, associated with violations of expectations, whereas the rare tones, being predictable, did not. The rare tones elicited the mismatch negativity (MMN), a component associated with preattentive deviance detection, despite the fact that they were expected. RT was faster in the predictable condition than in another condition in which the tones were not predictable. The P3 and RT data indicate, respectively, that subjects anticipated and were ready to respond to the target tones. The MMN result indicates that immediately before target tones, the preattentive system underlying the MMN was set for frequent tones, being unaffected by the information available to the higher order system. Thus, the higher order cognitive system associated with P3 and the lower order cognitive system associated with the MMN were prepared simultaneously for opposite events.
在一个“执行/不执行”反应时（RT）任务中记录事件相关电位（ERP），在该任务中，受试者对罕见的目标音调做出反应，而对频繁出现的音调不做反应。在可预测条件下，一个罕见的视觉刺激预示着即将出现一个罕见音调，而一个频繁出现的视觉刺激则预示着将呈现一个频繁出现的音调。罕见的视觉刺激引发了与预期违背相关的P3，而可预测的罕见音调则没有。尽管罕见音调是可预测的，但它们仍引发了失配负波（MMN），这是一种与前注意偏差检测相关的成分。在可预测条件下的反应时比音调不可预测的另一种条件下更快。P3和反应时数据分别表明，受试者预期并准备好对目标音调做出反应。MMN结果表明，就在目标音调出现之前，MMN背后的前注意系统针对频繁出现的音调进行了设置，不受高阶系统可用信息的影响。因此，与P3相关的高阶认知系统和与MMN相关的低阶认知系统同时为相反的事件做好了准备。
