• Korean Journal of Cognitive Science
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• v.24 no.1
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• pp.49-69
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• 2013

While we interact with other people or objects, the brain continuously updates our own body schema to recognize the agent of observed actions. The Extrastriate Body Area (EBA) provides an initial interface for the sense of agency by integrating visual inputs of body parts with internal signals related to self-generated body movements. Less is known, however, about how the functional use of tools contributes to such processes. Here, we investigated whether tool-specific affordance would differentially affect the neural responses in the EBA depending on the agency of imaginary actions. In each trial we presented a picture of an object in a rectangular frame. Objects were either the tools typically brought towards the body (body tools; e.g., telescope, earphones) or away from the body (world tools; e.g., pen, dice; Rueschemeyer, Pfeiffer, & Bekkering, 2010). Depending on the color of the frame, participants imagined either themselves or the other person using the tool (self vs. other conditions). These four types of trials were randomly intermixed with blank trials. As results, independently localized right EBA regions of interest showed greater activation when participants imagined themselves using body tools than using world tools whereas no such differential activations were found when they imagined the other person using the tools. The postscan test revealed no significant difference in vividness of imagery between the self and other conditions. Our results suggest that the EBA incorporates functional affordance of tools into the body schema in order to enhance the sense of agency and to guide our own actions.