Cue-induced task preparation in task set switching: Adaptability to contextual demands

任务提示用于告知个体即将到来的任务的性质，并提示任务准备。我们之前的研究表明，仅仅呈现与给定任务集相关的任务线索，就会影响随后的隐藏语义启动和任务切换效应。更具体地说，提示但未执行的任务集被迅速抑制，以便为即将到来的任务做准备。这种任务线索诱导的处理依赖于上下文需求，比如对任务执行需求的期望。本项目扩展了之前的工作，从灵活性（跨环境的变化）和可塑性（在一个实验过程中的变化）方面详细阐明了线索诱导加工的动态。任务线索诱导的处理包括任务准备和任务集激活，但也包括在准备即将到来的任务时可能出现的后续任务集抑制，如果线索任务集没有执行的话。在这个项目中，我们将重点关注任务切换情况下的任务线索诱导处理，因为任务切换是在可控框架内研究任务准备变化的合适工具。我们假设线索诱导的任务处理不是以“全有或全无”的方式进行，而是根据上下文需求灵活调整，并在实验过程中发生变化。在八个实验中，我们通过解决以下具体研究问题，旨在测试任务切换范式下线索诱导的任务准备过程的情境依赖性和适应性：(i)我们测试了在不需要的情况下线索诱导的加工是否可以被策略性地保留（实验1和2）。（ii）我们研究了线索诱导的加工是否取决于任务集切换与重复的期望（实验3和4）以及刺激集中的高干扰与低干扰（实验5和6）。（iii）我们评估了任务执行期望对任务准备的逐渐影响，这是由任务线索引起的，随后的任务执行要求逐渐变化提示呈现在实验过程中（实验7和8）。为了研究任务线索诱发的加工，我们将收集反应时间（RT）和错误率（ER），以及脑电活动。通过这些实验，我们期望对线索诱导加工的机制和过程获得重要的新见解。特别是，我们希望阐明线索诱导加工的灵活性和可塑性方面的动态。这个项目的结果与认知控制适应性的经验和理论方法有关，特别是任务准备的适应性。我们的研究结果也可能对实际应用有重要意义，比如人机交互，在人机交互中，线索被用来指示即将到来的系统干预。

Task cues are used to inform individuals about the nature of an upcoming task and to prompt task preparation. We previously showed mere presentation of task cues associated with a given task set to influence subsequent masked semantic priming and task switching effects. More specifically, cued, but not executed task sets were rapidly suppressed in preparation for an upcoming task. This task cue induced processing depended on contextual demands such as expectations of the requirements of task execution. The present project extends this previous work by elucidating in detail the dynamics of cue-induced processing in terms of flexibility (changes across contexts) and plasticity (changes during the course of one experimental session). Task cue-induced processing includes both task preparation and task set activation, but also possible subsequent task set inhibition in preparation for an upcoming task, if the cued task set is not executed. In this project, we will focus on task cue-induced processing specifically in task switching situations, because task switching is a suitable tool for investigating such changes in task preparation within a controllable framework. We assume cue-induced task processing to not proceed in an "all-or nothing" fashion, but to be flexibly adjusted according to contextual demands as well as to change during the course of an experiment. In eight experiments, we aim to test the context-dependence and adaptability of cue-induced task preparation processes within a task switching paradigm by addressing the following specific research questions: (i) We test whether cue-induced processing can be strategically withheld if not required (Experiments 1 and 2). (ii) We investigate whether cue-induced processing depends on expectations of task set switches vs. Repetitions (Experiments 3 and 4) and high vs. Low interference within the stimulus set (Experiments 5 and 6). (iii) We assess the gradual effects of expectations of task execution on task preparation induced by task cues by gradually varying requirements of task execution subsequent to cue presentation during the course of the experimental session (Experiments 7 and 8). To investigate task cue-induced processing, we will collect response times (RT) and error rates (ER), as well as brain electrical activity. With these lines of experiments, we expect to obtain important novel insights into the mechanisms and processes underlying cue-induced processing. In particular, we expect to elucidate the dynamics of cue-induced processing in terms of flexibility and plasticity. The results of this project are relevant for empirical and theoretical approaches to the adaptability of cognitive control in general and to that of task preparation in particular. Our findings could have also important implications for practical applications such as in human machine interaction, in which cues are used to signal upcoming system interventions.