Electrophysiological evidence that top-down knowledge controls working memory processing for subsequent visual search
Electrophysiological evidence that top-down knowledge controls working memory processing for subsequent visual search
复制标题
电生理证据表明自上而下的知识控制着后续视觉搜索的工作记忆处理
DOI：
10.1097/wnr.0000000000000545
复制
发表时间：
2016
期刊：
影响因子：
1.7
通讯作者：
E.
中科院分区：
文献类型：
--
作者：
Kawashima;T.;& Matsumoto;E.
工作记忆中的项目将视觉注意力引导到记忆匹配的物体上。最近的研究表明，当搜索一个对象时，这种注意引导可以通过知道目标与工作记忆中的项目匹配的概率来调节。在此，我们记录了P3和对侧延迟活动，以探讨自上而下的知识如何控制工作记忆项目的加工。参与者进行记忆任务（识别）和记忆或搜索任务（识别或视觉搜索），其中他们被要求保持两个彩色定向酒吧在工作记忆。对于视觉搜索，我们操纵了目标与记忆项目颜色相同的概率（0，50或100%）。参与者在任务之前就知道了概率。100%匹配条件下的目标检测速度比50%匹配条件下的目标检测速度快，表明参与者使用了他们的概率知识。我们发现，在100%的条件下的P3振幅大于在其他条件下，对侧延迟活动振幅并没有变化的条件。这些结果表明，当观察者事先知道记忆项目的颜色可能与目标匹配时，他们会将更多的注意力分配给记忆项目。这导致了更好的搜索性能，尽管使用定性相等的工作记忆表示。
Items in working memory guide visual attention toward a memory-matching object. Recent studies have shown that when searching for an object this attentional guidance can be modulated by knowing the probability that the target will match an item in working memory. Here, we recorded the P3 and contralateral delay activity to investigate how top–down knowledge controls the processing of working memory items. Participants performed memory task (recognition only) and memory-or-search task (recognition or visual search) in which they were asked to maintain two colored oriented bars in working memory. For visual search, we manipulated the probability that target had the same color as memorized items (0, 50, or 100%). Participants knew the probabilities before the task. Target detection in 100% match condition was faster than that in 50% match condition, indicating that participants used their knowledge of the probabilities. We found that the P3 amplitude in 100% condition was larger than in other conditions and that contralateral delay activity amplitude did not vary across conditions. These results suggest that more attention was allocated to the memory items when observers knew in advance that their color would likely match a target. This led to better search performance despite using qualitatively equal working memory representations.