You Can('t) Always Get What You Want: When Goal Persistence Requires Flexibility

Cognitive flexibility and stability are usually thought of as two antagonistic control demands: Flexibility allegedly comes at the cost of increased distractibility and reduced stability whereas stability comes at the cost of increased rigidity and reduced flexibility. Here, we question a rigorous antagonism by asking whether goal persistence in some situations can also promote behavioral flexibility. Using a voluntary task switching paradigm with double registration, participants first chose a task and then-on a subset of trials-were confronted with a nonchosen task (invalid trials). Across three experiments and after increasing goal stability by remaining high reward prospect, we found that participants showed a higher voluntary switch rate (VSR) after such invalid trials than after valid trials where the chosen task could directly be executed. Experiments 2 and 3 further demonstrated that the increased VSR after invalid trials was due to more frequent than chance switches back to the task that was prevented from execution. This is taken as evidence that goal persistence motivated by remaining high reward prospect can be accompanied by increased behavioral flexibility (voluntary task switch) to enable the execution of the unfulfilled goal.