Pashler H
Department of Psychology, University of California at San Diego, La Jolla 92093.
J Exp Psychol Hum Percept Perform. 1994 Apr;20(2):330-42. doi: 10.1037//0096-1523.20.2.330.
Research suggests that dual-task interference is caused by a central bottleneck (together with response grouping and impaired preparation). The emphasis placed on the 1st response in these experiments, however, may have discouraged the sharing of processing resources between tasks. In the present experiment, instructions placed equal emphasis on 2 choice reaction-time tasks in which stimuli were presented simultaneously on 20% of the trials. In contrast to a graded trade-off of resources, a bottleneck predicts bimodality in the distribution of interresponse intervals for the 2 tasks, reflecting the 2 possible orders in which their respective central stages might be performed. Most subjects showed such a bimodality, along with other signs of a bottleneck; the remainder showed evidence of response grouping. The data suggest that the bottleneck is structural rather than strategic and make the graded sharing of resources less plausible.
研究表明，双任务干扰是由一个中央瓶颈（以及反应分组和准备不足）引起的。然而，这些实验中对第一个反应的强调可能阻碍了任务之间处理资源的共享。在本实验中，指令对两个选择反应时任务给予同等的强调，其中在20%的试验中同时呈现刺激。与资源的分级权衡不同，瓶颈预测了两个任务的反应间隔分布中的双峰性，反映了它们各自中央阶段可能执行的两种可能顺序。大多数受试者表现出这种双峰性以及其他瓶颈迹象；其余受试者则表现出反应分组的证据。数据表明，瓶颈是结构性的而非策略性的，这使得资源的分级共享不太可信。
