Motor simulation beyond the dyad: Automatic imitation of multiple actors.

A large body of research has provided evidence for the idea that individuals simulate the actions of others in their motor system. However, this research has focused almost exclusively on dyadic situations, hence ignoring the fact that social situations often require that the actions of multiple persons are simulated simultaneously. In the current study, we addressed this issue by means of a widely used automatic imitation task. In Experiment 1, it is shown that individuals automatically imitate the actions of 2 agents at the same time. More specifically, the results indicate that 2 identical observed movements produce a stronger imitation effect, whereas 2 different observed movements produce 2 opposite imitation effects that cancel each other out. In Experiment 2, it is shown that the effects obtained in Experiment 1 cannot be explained in terms of attentional capture. Instead, the results point toward an explanation in terms of ideomotor theory. The finding that observers simultaneously represent the actions of multiple agents in their motor system allows for a better understanding of social interaction beyond the dyad.