University of Tennessee, Knoxville.
University of Iowa.
J Cogn Neurosci. 2021 Jun 1;33(7):1365-1380. doi: 10.1162/jocn_a_01720.
Flexibly shifting attention between stimulus dimensions (e.g., shape and color) is a central component of regulating cognition for goal-based behavior. In the present report, we examine the functional roles of different cortical regions by manipulating two demands on task switching that have been confounded in previous studies-shifting attention between visual dimensions and resolving conflict between stimulus-response representations. Dimensional shifting was manipulated by having participants shift attention between dimensions (either shape or color; dimension shift) or keeping the task-relevant dimension the same (dimension same). Conflict between stimulus-response representations was manipulated by creating conflict between response-driven associations from the previous set of trials and the stimulus-response mappings on the current set of trials (e.g., making a leftward response to a red stimulus during the previous task, but being required to make a rightward response to a red stimulus in the current task; stimulus-response conflict), or eliminating conflict by altering the features of the dimension relevant to the sorting rule (stimulus-response no-conflict). These manipulations revealed activation along a network of frontal, temporal, parietal, and occipital cortices. Specifically, dimensional shifting selectively activated frontal and parietal regions. Stimulus-response conflict, on the other hand, produced decreased activation in temporal and occipital cortices. Occipital regions demonstrated a complex pattern of activation that was sensitive to both stimulus-response conflict and dimensional attention switching. These results provide novel information regarding the distinct role that frontal cortex plays in shifting dimensional attention and posterior cortices play in resolving conflict at the stimulus level.
灵活地在刺激维度（例如形状和颜色）之间转移注意力是基于目标的行为调节认知的核心组成部分。在本报告中，我们通过操纵先前研究中混淆的两种任务转换要求来检查不同皮质区域的功能作用-在视觉维度之间转移注意力和解决刺激-反应表示之间的冲突。通过让参与者在维度（形状或颜色；维度转换）之间或保持任务相关维度不变（维度相同）来操纵维度转换。通过在前一组试验的反应驱动关联与当前组试验的刺激-反应映射之间产生冲突（例如，在前一个任务中对红色刺激做出向左的反应，但在当前任务中被要求对红色刺激做出向右的反应；刺激-反应冲突），或者通过改变与分类规则相关的维度特征来消除冲突（刺激-反应无冲突），来操纵刺激-反应表示之间的冲突。这些操作揭示了沿着额、颞、顶和枕皮质网络的激活。具体来说，维度转换选择性地激活了额皮质和顶皮质区域。另一方面，刺激-反应冲突导致颞皮质和枕皮质的激活减少。枕皮质区域表现出一种复杂的激活模式，对刺激-反应冲突和维度注意转换都很敏感。这些结果提供了关于额皮质在转换维度注意力方面的独特作用以及后皮质在解决刺激水平冲突方面的作用的新信息。
