Think differently:: a brain orienting response to task novelty
Think differently:: a brain orienting response to task novelty
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DOI：
10.1097/00001756-200210280-00011
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发表时间：
2002-10-28
期刊：
影响因子：
1.7
通讯作者：
Knight, RT
中科院分区：
文献类型：
--
作者：
Barceló, F;Periáñez, JA;Knight, RT
认知的灵活性取决于将注意力集中在新事件上的准备程度，以及改变一个人的心理状态以找到解决老问题的新方法的能力。人类事件相关电位（ERP）研究已经描述了大脑对离散的新事件的“定向”反应，其特征在于刺激后300-400 ms（P3 a）达到峰值的前部分布的正电位。这种大脑潜能通常与在固定任务集下对新的非目标的自下而上的处理有关（即，按一个按钮到彩色目标），但从来没有涉及到双任务范式中自上而下的注意力控制。在这项研究中，27名受试者在进行威斯康星州卡片分类测试（WCST）的同时测量了他们的ERP，WCST是一种双任务范式，其中相同的反馈提示表明了不可预测的新任务集的转移（即，从“按颜色排序”到“按形状排序”）。反馈线索，引导受试者的心理设置到一个新的任务集的转移引起正面分布的P3 a活动，从而表明任务集转移的P3 a反应系统的作用。反馈线索也诱发了较长的潜伏期正电位（350-600 ms; P3 b），这是更大的任务规则，在内存中举行。与当前注意力执行控制中的前额叶功能模型一致，P3 a/P3 b反应系统似乎反映了工作记忆中任务集切换和更新过程中前额叶和后联想皮层的协调作用。
Cognitive flexibility hinges on a readiness to direct attention to novel events, and on an ability to change one's mental set to find new solutions for old problems. Human event-related potential (ERP) studies have described a brain 'orienting' response to discrete novel events, marked by a frontally distributed positive potential peaking 300-400 ms post-stimulus (P3a). This brain potential has been typically related to bottom-up processing of novel non-targets under a fixed task-set (i.e., press a button to coloured targets), but had never been related to top-down attention control in dual-task paradigms. In this study, 27 subjects had their ERPs measured while they performed a version of the Wisconsin card sorting test (WCST), a dual-task paradigm where the same feedback cue signalled unpredictable shifts to a new task set (i.e., from 'sort by colour' to 'sort by shape'). Feedback cues that directed a shift in the subject's mental set to a new task-set elicited frontally distributed P3a activity, thus suggesting a role of the P3a response system in task-set shifting. Feedback cues also evoked a longer latency positive potential (350-600 ms; P3b), that was larger the more task rules were held in memory. In line with current models of prefrontal function in the executive control of attention, this P3a/P3b response system appears to reflect the co-ordinated action of prefrontal and posterior association cortices during the switching and updating of task sets in working memory.