Résumé
Motor imagery (MI), the mental simulation of movement without physical execution, engages neural and behavioral mechanisms similar to those involved in physical movement. Although extensive research has examined how individuals engage in MI when they act alone, little is known about MI of joint actions when an individual imagines coordinating with a partner. Recent evidence suggests that joint MI is shaped not only by one’s own motor plans, but also representations of a partner’s assumed action capabilities. The present study investigated whether imagining a joint action is more cognitively demanding than imagining the same action performed alone. The task involved transferring 4 discs onto a post. Participants (n=28) performed this task alone and imagined performing it alone and with an imagined partner. This task was performed and imagined on its own (single-task) and with a concurrent mental calculation task (dual-task). Results showed that the dual-task disrupted imagined movement times (MTs) more than physical MTs. Critically, the dual-task had a greater impact on imagined MTs in the joint MI task compared to imagined MTs in the individual MI task. Motor overflow, unintended micromovements during MI that are a measure of inhibitory control, increased under dual-task conditions, but did not differ between individual and joint MI tasks. These findings suggest that imagining joint actions is not merely a combination of two individual simulations, but a more cognitively demanding process involving perspective-taking, anticipation, and coordination. This work has important implications for MI training in sport and rehabilitation, where interpersonal coordination is vital.
