Previous research suggests that non-verbal mimicry, the copying of another’s body movements during interpersonal interactions, is associated with better relationships because it enhances the mimickee’s perception of the mimicker. However, in light of the intergroup divisions that increasingly polarise our society, it is unclear whether such positive effects of non-verbal mimicry can be sustained when the group membership of the interacting individuals differs. Using Social Identity Theory as a theoretical framework, I examine the effects of non- verbal mimicry on how the mimickers are perceived across both intra- and intergroup contexts. I conducted two large-scale experiments to study the role of social identities in moderating the effects of non-verbal mimicry in interpersonal interactions on the one hand, and the mechanism behind the mimicry-likability effect on the other. Specifically, participants interacted directly with a role-playing experimenter demonstrating different levels of mimicry and different group affiliations across conditions and then rated the mimicker afterwards. Interestingly, the results suggest that it may not be mimicry per se that is associated with favourable perceptions of the mimicker, as suggested by the literature, but rather that a “static behaviour” control condition is associated with unfavourable perceptions. Accordingly, the mechanism by which dyadic mimicry operates appears to be different from what the literature suggests. The results also showed that social identities moderated this effect. Out-group members, but not in-group members, were judged as particularly less likeable when they displayed static behaviour compared to both neutral behaviour and mimicry. These experiments contribute to the literature not only methodologically by revealing the importance of specific control conditions, but they also indicate the importance of social group membership in judging individual behaviour.
The third experiment was conducted online with pre-recorded videos to explore the vicarious effects of non-verbal mimicry and social identities. In contrast to the interpersonal experiments, the results here suggested that vicarious mimicry was associated with greater likability and competence (and partly trustworthiness) of the mimicker, as rated by the observer (i.e., the participants) when compared with both static and neutral behaviour control conditions. Importantly, some of these effects were moderated by social groups. Specifically, though out- group members, compared to in-group members, were perceived as less competent and trustworthy in the no mimicry condition, these biases were diminished in the vicarious mimicry condition. Thus, this is the first experiment that reveals the important role of observed mimicry in reducing intergroup biases, thereby providing promising evidence for a behaviour-based reduction of prejudice. Though scholars often presuppose a dyadic nature of mimicry, this study further contributes to the literature by showing that mimicry may tap into a broader concept of social affiliation instead.
