Woodward Todd S, Meier Beat, Tipper Christine, Graf Peter
Department of Psychology, University of British Columbia, Vancouver, Canada.
Exp Psychol. 2003;50(4):233-8. doi: 10.1026//1618-3169.50.4.233.
When performing tasks in alternation, substantial slowing occurs when the stimuli have features relevant to both tasks (i.e., when stimuli are bivalent as opposed to univalent). One possible source of this slowing, herein called a bivalency cost, is that encountering bivalent stimuli leads to a more cautious response style. To investigate this, we employed a paradigm that required performing three simple tasks, with bivalent stimuli occasionally encountered on one task. The results show that regardless of the feature overlap among the stimuli used for the different tasks, the introduction of bivalent stimuli slowed responding on all tasks and it was accompanied by a decrease in response errors. Overall, it appears that bivalent stimuli recruit a more cautious approach to task-switching performance.
当交替执行任务时，如果刺激具有与两个任务都相关的特征（即，与单值刺激相对，刺激是双值的），就会出现明显的反应减慢。这种减慢的一个可能来源，在此称为双值代价，是遇到双值刺激会导致更谨慎的反应方式。为了对此进行研究，我们采用了一种范式，该范式要求执行三个简单任务，其中在一个任务上偶尔会遇到双值刺激。结果表明，无论用于不同任务的刺激之间的特征重叠如何，双值刺激的引入都会减慢所有任务的反应速度，并且伴随着反应错误的减少。总体而言，似乎双值刺激会促使在任务切换表现中采用更谨慎的方法。
