Harris Anthony M, Jacoby Oscar, Remington Roger W, Becker Stefanie I, Mattingley Jason B
Queensland Brain Institute, The University of Queensland, St Lucia, 4072, Australia.
Queensland Brain Institute, The University of Queensland, St Lucia, 4072, Australia.
Cortex. 2020 Aug;129:158-174. doi: 10.1016/j.cortex.2020.04.009. Epub 2020 May 4.
When attending to visual objects with particular features, neural processing is typically biased toward those features. Previous work has suggested that maintaining such feature-based attentional sets may involve the same neural resources as visual working memory. If so, the extent to which feature-based attention influences stimulus processing should be related to individuals' working memory capacity. Here we used electroencephalography (EEG) to record brain activity in 60 human observers while they monitored stimulus streams for targets of a specific color. Distractors presented at irrelevant locations evoked strong electrophysiological markers of attentional signal enhancement (the N2pc and P components) despite producing little or no behavioral interference. Critically, there was no relationship between individual differences in the magnitude of these feature-based biases on distractor processing and individual differences in working memory capacity as measured using three separate working memory tasks. Bayes factor analyses indicated substantial evidence in support of the null hypothesis of no relationship between working memory capacity and the effects of feature-based attention on distractor processing. We consider three potential explanations for these findings. One is that working memory and feature-based attention draw upon distinct neural resources, contrary to previous claims. A second is that working memory is only related to feature-based attention when the attentional template has recently changed. A third is that feature-based attention tasks of the kind employed in the current study recruit just one of several subcomponents of working memory, and so are not invariably correlated with an individual's overall working memory capacity.
当关注具有特定特征的视觉对象时，神经处理通常会偏向于这些特征。先前的研究表明，维持这种基于特征的注意集可能涉及与视觉工作记忆相同的神经资源。如果是这样，基于特征的注意对刺激处理的影响程度应该与个体的工作记忆容量相关。在这里，我们使用脑电图（EEG）记录了60名人类观察者在监测特定颜色目标的刺激流时的大脑活动。尽管干扰物在无关位置呈现时几乎没有产生行为干扰，但却引发了强烈的注意信号增强的电生理标记（N2pc和P成分）。关键的是，使用三个单独的工作记忆任务测量的干扰物处理中这些基于特征的偏差大小的个体差异与工作记忆容量的个体差异之间没有关系。贝叶斯因子分析表明有大量证据支持工作记忆容量与基于特征的注意对干扰物处理的影响之间不存在关系的零假设。我们考虑了对这些发现的三种潜在解释。一种是工作记忆和基于特征的注意利用不同的神经资源，这与先前的说法相反。第二种是只有当注意模板最近发生变化时，工作记忆才与基于特征的注意相关。第三种是本研究中使用的基于特征的注意任务只招募了工作记忆的几个子成分之一，因此并不总是与个体的整体工作记忆容量相关。
