Department of Psychology, University of Copenhagen, Denmark.
Neuropsychologia. 2011 May;49(6):1487-97. doi: 10.1016/j.neuropsychologia.2010.11.039. Epub 2010 Dec 9.
The allocation of visual processing capacity is a key topic in studies and theories of visual attention. The load theory of Lavie (1995) proposes that allocation happens in two steps where processing resources are first allocated to task-relevant stimuli and secondly remaining capacity 'spills over' to task-irrelevant distractors. In contrast, the Theory of Visual Attention (TVA) proposed by Bundesen (1990) assumes that allocation happens in a single step where processing capacity is allocated to all stimuli, both task-relevant and task-irrelevant, in proportion to their relative attentional weight. Here we present data from two partial report experiments where we varied the number and discriminability of the task-irrelevant stimuli (Experiment 1) and perceptual load (Experiment 2). The TVA fitted the data of the two experiments well thus favoring the simple explanation with a single step of capacity allocation. We also show that the effects of varying perceptual load can only be explained by a combined effect of allocation of processing capacity as well as limits in visual working memory. Finally, we link the results to processing capacity understood at the neural level based on the neural theory of visual attention by Bundesen et al. (2005).
视觉加工容量的分配是视觉注意研究和理论中的一个关键主题。拉维（Lavie）的负荷理论（1995）提出，分配分两步进行，首先将处理资源分配给与任务相关的刺激，其次剩余的容量“溢出”到与任务无关的分心物上。相比之下，邦德森（Bundesen）提出的视觉注意理论（TVA）假设分配在单个步骤中进行，其中处理容量根据其相对注意力权重分配给所有刺激，包括与任务相关的刺激和与任务无关的刺激。在这里，我们展示了两个部分报告实验的数据，其中我们改变了与任务无关的刺激的数量和可辨别性（实验 1）和知觉负荷（实验 2）。TVA 很好地拟合了这两个实验的数据，因此支持了单一的容量分配步骤的简单解释。我们还表明，知觉负荷的变化效应只能通过处理容量的分配以及视觉工作记忆的限制的综合效应来解释。最后，我们根据邦德森等人（2005）的神经视觉注意理论，将结果与基于神经水平的处理容量联系起来。
