Brain and psychological mediators of imitation: sociocultural versus physical traits.

The acquisition of cultural beliefs and practices is fundamental to human societies. The psychological and neural mechanisms underlying cultural acquisition, however, are not well understood. Here we used brain imaging to investigate how others' physical and sociocultural attributes may influence imitative learning, a critical component of cultural acquisition. While undergoing fMRI, 17 European American young adults imitated models from three different racial groups performing novel hand gestures. Participants learned that half the models shared their political ideology and half did not. We found that the model's political ideology-a sociocultural characteristic devoid of any physical correlates-was sufficient to influence imitative accuracy, and that this effect was mediated by changes in feelings of similarity to the model. Furthermore, the relationship between the imitative model's political ideology and imitation accuracy was mediated by brain regions associated with imitation and its control, as well as mentalizing. Finally, comparing these new data with those from one of our previous studies revealed that knowledge of a model's political ideology reduces the influence of the model's race on feelings of similarity to the model and imitation accuracy, as well as activity in brain regions typically activated during imitation. Taken together, these findings suggest that (1) others' sociocultural characteristics influence imitative biases more so than their physical attributes, and (2) that neural systems associated with imitation, imitation control, and mentalizing contribute to this cultural learning process.