Fischer Rico, Dreisbach Gesine
Department of Psychology.
Department of Experimental Psychology.
J Exp Psychol Hum Percept Perform. 2015 Dec;41(6):1482-7. doi: 10.1037/xhp0000157. Epub 2015 Oct 19.
The simultaneous handling of 2 tasks requires shielding of the prioritized primary task (T1) from interference caused by the secondary task (T2) processing. Such interactions between tasks (e.g., between-task interference, or crosstalk) depend on the similarity of both tasks and are especially pronounced when both tasks overlap strongly in time. In the present study we investigated whether between-tasks interference can be reduced when specific items do not predict the level of interference but instead the degree of temporal proximity between both tasks. We implemented an item-specific proportion manipulation of temporal task overlap (stimulus onset asynchrony [SOA]). Selected stimuli of T1 predicted high temporal task overlap (short SOAs) in 80% of trials, whereas other stimuli of T1 predicted low temporal task overlap (long SOAs) in 80% of trials. Results showed that the predictive value of T1 stimuli determined the adjustment of T1 shielding. That is, interference from the secondary task was significantly reduced for items predicting high temporal task overlap compared to items predicting low temporal task overlap. It is important to note that task shielding was not initiated by predicting the actual conflict level (i.e., whether T1 and T2 required compatible/incompatible responses) between tasks but by specific items predicting conditions in which 2 tasks are likely to interact (i.e., short vs. long SOA). These findings offer new insights into the specificity of contextual bottom-up regulations of cognitive control.
同时处理两项任务需要对优先级较高的主要任务（T1）进行屏蔽，使其免受次要任务（T2）处理所造成的干扰。任务之间的这种相互作用（例如，任务间干扰或串扰）取决于两项任务的相似性，并且当两项任务在时间上高度重叠时尤为明显。在本研究中，我们调查了在特定项目不预测干扰水平而是预测两项任务之间的时间接近程度时，任务间干扰是否能够减少。我们对时间任务重叠（刺激开始异步性[SOA]）实施了特定项目比例的操纵。T1的选定刺激在80%的试验中预测了高时间任务重叠（短SOA），而T1的其他刺激在80%的试验中预测了低时间任务重叠（长SOA）。结果表明，T1刺激的预测价值决定了T1屏蔽的调整。也就是说，与预测低时间任务重叠的项目相比，预测高时间任务重叠的项目受到次要任务的干扰显著减少。需要注意的是，任务屏蔽不是通过预测任务之间的实际冲突水平（即T1和T2是否需要兼容/不兼容的反应）来启动的，而是通过预测两项任务可能相互作用的条件（即短SOA与长SOA）的特定项目来启动的。这些发现为认知控制的情境自下而上调节的特异性提供了新的见解。
