Context-sensitive adjustment of cognitive control in dual-task performance.

Performing 2 highly similar tasks at the same time requires an adaptive regulation of cognitive control to shield prioritized primary task processing from between-task (cross-talk) interference caused by secondary task processing. In the present study, the authors investigated how implicitly and explicitly delivered information promotes the flexible online adjustment of task shielding in dual-task performance. Context-specific implicit activation of cognitive control was implemented by location-dependent manipulations of the likelihood of between-task interference (i.e., locations containing high vs. low proportions of between-task interference trials). Following practice, between-task interference was reduced in a subsequent test session for locations associated with high (compared to locations with low) task-shielding demands, indicating that the cognitive system can register and utilize implicit context features (Experiments 1 and 2). In Experiment 3, cues were used that provided additional explicit information. Whereas cues validly indicating the interference level in the next trial failed to further optimize context-specific task shielding, cues indicating the location of subsequent stimulus presentation resulted in an instant adjustment of task shielding already in the first part of the experiment. Results highlight the role of implicit and explicit information for context-sensitive adjustments of cognitive control in dual-task performance.