Giray M, Ulrich R
Psychologisches Institut, Universität Tübingen, Germany.
J Exp Psychol Hum Percept Perform. 1993 Dec;19(6):1278-91. doi: 10.1037//0096-1523.19.6.1278.
Four experiments examined effects of bimodal stimulation on response force (RF) in addition to reaction time (RT). In a divided-attention task (Experiments 1 to 3), subjects were asked for a speeded response to either a visual or an auditory signal. In unimodal signal trials, either a visual or an auditory signal was presented alone, and in redundant-signals trials, both signals were presented simultaneously. The same stimulus arrangement was used in a focused-attention task (Experiment 4), but subjects had to withhold their response when an auditory signal was presented alone. In all experiments, the fastest RTs were attained in redundant-signals trials. In addition, RF was largest in redundant-signals trials, especially in the divided-attention task, suggesting a motor coactivation hypothesis. The results indicate that the type of stimulation influences not only when a response is initiated but also how the response is executed. This finding challenges the view, commonly held in mental chronometry, that late motoric processes remain untouched by experimental manipulations. A detailed analysis of the relationship between RT and RF revealed that these variables are not inherently redundant measures, and, therefore, RF recording may supplement the traditional RT measurement in mental chronometry.
四项实验除了考察了双模式刺激对反应时（RT）的影响外，还考察了其对反应力（RF）的影响。在一项分心任务（实验1至3）中，要求受试者对视觉或听觉信号做出快速反应。在单模式信号试验中，单独呈现视觉或听觉信号，而在冗余信号试验中，两个信号同时呈现。在一项集中注意力任务（实验4）中使用了相同的刺激安排，但当单独呈现听觉信号时，受试者必须抑制自己的反应。在所有实验中，冗余信号试验中获得了最快的反应时。此外，冗余信号试验中的反应力最大，尤其是在分心任务中，这表明了一种运动共同激活假说。结果表明，刺激类型不仅影响反应的启动时间，还影响反应的执行方式。这一发现挑战了心理计时学中普遍持有的观点，即后期运动过程不受实验操作的影响。对反应时和反应力之间关系的详细分析表明，这些变量并非本质上冗余的测量指标，因此，反应力记录可能会补充心理计时学中传统的反应时测量方法。
