Bettencourt Katherine C, Michalka Samantha W, Somers David C
Department of Psychology, Boston University, Boston, MA, USA.
J Vis. 2011 Sep 30;11(10):22. doi: 10.1167/11.10.22.
Both visual attention and visual short-term memory (VSTM) have been shown to have capacity limits of 4 ± 1 objects, driving the hypothesis that they share a visual processing buffer. However, these capacity limitations also show strong individual differences, making the degree to which these capacities are related unclear. Moreover, other research has suggested a distinction between attention and VSTM buffers. To explore the degree to which capacity limitations reflect the use of a shared visual processing buffer, we compared individual subject's capacities on attentional and VSTM tasks completed in the same testing session. We used a multiple object tracking (MOT) and a VSTM change detection task, with varying levels of distractors, to measure capacity. Significant correlations in capacity were not observed between the MOT and VSTM tasks when distractor filtering demands differed between the tasks. Instead, significant correlations were seen when the tasks shared spatial filtering demands. Moreover, these filtering demands impacted capacity similarly in both attention and VSTM tasks. These observations fail to support the view that visual attention and VSTM capacity limits result from a shared buffer but instead highlight the role of the resource demands of underlying processes in limiting capacity.
视觉注意力和视觉短期记忆（VSTM）均已被证明存在4±1个物体的容量限制，这促使人们提出它们共享一个视觉处理缓冲区的假设。然而，这些容量限制也表现出强烈的个体差异，使得这些容量之间的相关程度尚不清楚。此外，其他研究表明注意力缓冲区和VSTM缓冲区存在区别。为了探究容量限制在多大程度上反映了共享视觉处理缓冲区的使用情况，我们比较了个体受试者在同一测试环节中完成的注意力任务和VSTM任务的容量。我们使用了多目标跟踪（MOT）和VSTM变化检测任务，并设置了不同水平的干扰物来测量容量。当两项任务的干扰物过滤要求不同时，未观察到MOT任务和VSTM任务在容量上存在显著相关性。相反，当两项任务共享空间过滤要求时，则观察到显著相关性。此外，这些过滤要求对注意力任务和VSTM任务容量的影响相似。这些观察结果不支持视觉注意力和VSTM容量限制源于共享缓冲区的观点，而是突出了底层过程的资源需求在限制容量方面的作用。
