Dell'Acqua R, Jolicoeur P
Department of Psychology, University of Padova, Italy.
Mem Cognit. 2000 Mar;28(2):184-91. doi: 10.3758/bf03213798.
Two stimuli were presented at varying stimulus onset asynchronies (SOAs), with each stimulus associated with a distinct task. The first stimulus was a tone at one of either two or three frequencies. In two conditions, the task associated with a tone was either a speeded two-alternative discrimination (2AD), or a speeded three-alternative discrimination (3AD) based on the pitch of the tone. In a third condition, subjects were told to ignore the tone. The second stimulus was a briefly exposed study matrix of red and black squares followed by a mask. After a fixed delay, the mask was replaced by a test matrix that was either the same or different from the study matrix. The task associated with the matrices was to indicate, with no speed pressure, whether the study matrix and the test matrix were the same or different. Results from each speeded AD condition showed that subject's accuracy in the matrix task decreased as the SOA between the tone and the study matrix decreased. This effect was larger for the 3AD tone task than with a 2AD tone task. In addition, within each speeded AD condition, longer RTs in the tone task were associated with lower accuracy in the matrix task. None of these effects was evident when the subjects were told to ignore the tone. These results suggest that encoding visual information can be subject to significant capacity limitations imposed by cross-modal multitasking.
呈现了两种刺激，其刺激起始异步（SOA）各不相同，每种刺激都与一项不同的任务相关联。第一种刺激是一个频率为两个或三个频率之一的音调。在两种情况下，与音调相关的任务要么是基于音调音高的快速二选一辨别（2AD），要么是快速三选一辨别（3AD）。在第三种情况下，受试者被告知忽略该音调。第二种刺激是一个由红色和黑色方块组成的短暂呈现的研究矩阵，随后是一个掩蔽物。经过固定延迟后，掩蔽物被一个与研究矩阵相同或不同的测试矩阵所取代。与矩阵相关的任务是在没有速度压力的情况下指出研究矩阵和测试矩阵是否相同。每个快速AD条件的结果表明，随着音调与研究矩阵之间的SOA减小，受试者在矩阵任务中的准确性降低。这种效应在3AD音调任务中比在2AD音调任务中更大。此外，在每个快速AD条件下，音调任务中较长的反应时间与矩阵任务中较低的准确性相关。当受试者被告知忽略音调时，这些效应均不明显。这些结果表明，编码视觉信息可能会受到跨模态多任务施加的显著容量限制。
