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

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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.