We frequently engage in joint actions, where individuals coordinate to bring about changes in the environment. Such joint actions require planning of individual contributions and joint components beyond the individual level. Previous research suggests that specialized joint action plans integrate self and partner contributions to facilitate coordination.
One proposal is that co-actors generally prioritize joint-level planning over individual-level planning, as has been demonstrated in joint tasks requiring close coordination. Alternatively, co-actors may engage in joint-level planning only when it allows them to use joint-level information to better prepare their individual contributions.
Across four experiments (N = 24 each), we investigated when joint action partners adaptively choose between individual and joint action plans based on task demands. Participants performed a joint computer task requiring them to select one of two blocks to create a joint pattern. Two cues were presented before task specification: Joint cues indicated the relation between contributions, while individual cues specified either their own or their partner’s contribution. We manipulated the difficulty of integrating individual contributions with their outcomes and the sequence of presenting individual- and joint-level information during a joint task.
Response times were consistently shorter when joint cues specified the relation between individual contributions in partner trials. Crucially, joint cues benefitted task performance in self trials when the cues allowed participants to directly associate individual actions with outcomes.
These results suggest that co-actors strategically switch between joint and individual planning, but joint planning can take precedence when individual actions link directly to their outcomes.