School of Philosophy, Psychology and Language Sciences, University of Edinburgh, 7 George Square, EH8 9JZ, Edinburgh, United Kingdom.
School of Psychology, University of Aberdeen, William Guild Building, AB24 3UB, Aberdeen, United Kingdom.
Cereb Cortex. 2024 Jun 4;34(6). doi: 10.1093/cercor/bhae240.
Biological systems must allocate limited perceptual resources to relevant elements in their environment. This often requires simultaneous selection of multiple elements from the same feature dimension (e.g. color). To establish the determinants of divided attentional selection of color, we conducted an experiment that used multicolored displays with four overlapping random dot kinematograms that differed only in hue. We manipulated (i) requirement to focus attention to a single color or divide it between two colors; (ii) distances of distractor hues from target hues in a perceptual color space. We conducted a behavioral and an electroencephalographic experiment, in which each color was tagged by a specific flicker frequency and driving its own steady-state visual evoked potential. Behavioral and neural indices of attention showed several major consistencies. Concurrent selection halved the neural signature of target enhancement observed for single targets, consistent with an approximately equal division of limited resources between two hue-selective foci. Distractors interfered with behavioral performance in a context-dependent fashion but their effects were asymmetric, indicating that perceptual distance did not adequately capture attentional distance. These asymmetries point towards an important role of higher-level mechanisms such as categorization and grouping-by-color in determining the efficiency of attentional allocation in complex, multicolored scenes.
生物系统必须将有限的感知资源分配给环境中的相关元素。这通常需要同时从同一特征维度（例如颜色）中选择多个元素。为了确定颜色的分散注意力选择的决定因素，我们进行了一项实验，该实验使用了具有四个重叠随机点运动图的多色显示器，这些运动图仅在色调上有所不同。我们操纵了（i）将注意力集中在单一颜色或将其分散在两种颜色之间的要求；（ii）在感知颜色空间中，干扰颜色与目标颜色之间的距离。我们进行了行为和脑电图实验，其中每种颜色都标记有特定的闪烁频率，并驱动其自己的稳态视觉诱发电位。注意力的行为和神经指标显示出几个主要的一致性。同时选择将单一目标观察到的目标增强的神经特征减半，这与在两个色调选择性焦点之间分配有限资源的大致相等划分一致。干扰物以依赖上下文的方式干扰行为表现，但它们的影响是不对称的，这表明感知距离不能充分捕获注意力距离。这些不对称性表明，在复杂的多色场景中，分类和颜色分组等高级机制在确定注意力分配的效率方面起着重要作用。
