Sociomotor actions: Anticipated partner responses are primarily represented in terms of spatial, not anatomical features.

The sociomotor framework proposes that people can represent their actions in terms of the behavior these actions evoke in others, so that anticipating the behavior of others triggers own actions. In social interactions, such as imitation, it thus highlights the acting model rather than the responding person. In line with this idea, motor actions are facilitated if they are foreseeably imitated rather than counterimitated by a social partner. In the present study, we investigate how exactly another's behavior is represented in such sociomotor actions. The effect of being imitated can be explained by two distinct forms of compatibility between model and imitator actions: correspondence of anatomical features (imitative compatibility) and correspondence of spatial features (spatial compatibility). Both types of features often go hand in hand, though research on motor priming shows that spatial and anatomical features of other's actions are represented independently. We therefore investigated to which degree the benefit of anticipated imitation is caused by spatial or imitative compatibility. Across 5 experiments, we found that only spatial compatibility of the imitator's behavior influenced the model's actions, while imitative compatibility had no influence. Actors thus seem to represent actions of their social partners mainly in terms of nonsocial, spatial features. (PsycINFO Database Record (c) 2019 APA, all rights reserved).