注意对冲突监测事件相关电位N270的影响

目的：探讨注意对冲突监测事件相关电位N270的影响。方法：30名健康志愿者分成两组，一组人判断连续呈现的一对数字的颜色是否相同，不考虑数值（注意颜色）；另一组人判断连续呈现的一对数字的数值是否相同，不考虑颜色（注意数值），在头皮同步记录事件相关电位。结果：颜色不同和／或数值不同的数字对均可在第二个数字呈现后引起事件相关电位N270，颜色和数值完全相同的数字对则不引起该负波。与不被主动注意状态相比，刺激特征冲突被注意时引出的N270波幅更高，持续时间更长，起始潜伏期不变。结论：冲突监测系统的启动不受注意影响，而一旦启动后则受到注意系统的调节。

The Influence of Attentionon the Conflict Monitoring Event-related Potential N270

Objective:To examine influences of attention on the conflict monitoring system. Methods:Thirty normal adults participated in the matching-to-sample task. They were divided into two subgroups. One subgroup was required to attend to the color while ignoring the value attribute of a number pair. The other subgroup was required to attend to the value while ignoring the color attribute of a number pair. Subjects were asked to press one of the two buttons according to whether the two digits were identical in the attended attribute and event-related potentials were recorded on their scalps. Results: A N270 component of event-related potential was recorded to the conflicting stimulus pairs but not to the matching pairs. The amplitude of N270 increased and its duration prolonged under attended condition. However, its onset latency showed no significant changes. Conclusion: The conflict monitoring process is automatically initiated and then regulated and enhanced by the attention control system.