Cognitive demands for task preparation depend on task cue transparency

Task cues are often used to study task preparation. Participants are thought to activate cued task sets in advance to facilitate later task performance. Earlier studies showed that task performance was improved, if the relation of cue and decision categories of the task was more transparent, suggesting a facilitated task preparation process with more transparent cues. In contrast, we previously observed that the level of preparatory task set activation was comparable between four different cue types varying in task cue transparency (Berger et al., 2022). We hypothesized that participants could compensate for non-transparent cues by showing greater engagement in task preparation, thus achieving a similar level of task set activation compared to more transparent cues. To test this hypothesis, we analyzed cue-locked event-related potentials (ERPs) and oscillatory activity of the electroencephalogram (EEG) for four different cue types with varying cue transparency. Increased cue-locked positivity and decreased beta power indicated that task preparation demands were greater for non-transparent cues. However, these differences were mainly driven by arbitrary task cues for which there was no association between cue and decision category. For cues for which cues and decision categories could be linked at least via a mediator, the cue locked positivity and beta power were comparable. In conclusion, task cue transparency influenced electrophysiological correlates related to the preparatory demands required for task set retrieval and should therefore be taken into account when studying task preparation.