Does the Human Motor System Simulate Pinocchio's Actions?

Corepresenting actions performed by conspecifics is essential to understanding their goals, inferring their mental states, and cooperating with them. It has recently been demonstrated that joint-action effects in a Simon task provide a good index for corepresentation. In the present study, we investigated whether corepresentation is restricted to biological agents or also occurs for nonbiological events. Participants performed a Simon task either with an image of a human hand or with a wooden analogue. The Simon-like effect emerged only when participants coacted with a biological agent. The lack of the joint-action effect when participants interacted with a wooden hand indicates that the human corepresentation system is biologically tuned.