Relative to typical actions, actions that are purposeless, inappropriate and/or impossible along various dimensions (e.g., cutting jewelry on a plate with a knife and fork, cutting bread with a saw, standing on one foot in middle of desert) elicit N400 effects, suggesting functional similarity in comprehending everyday scenes and linguistic expressions of such (e.g., Proverbio & Riva 2009). Critically, both the appropriateness of the object used in an action (e.g., inserting screwdriver versus key into a keyhole) and the appropriateness of features of the motor act itself (e.g., orientation of the object with respect to the keyhole) individually and jointly modulate N400 amplitudes (Bach et al 2009), although topographic and durational differences implicate partially non-overlapping neural systems. Other N400 data have shown that the relationship between hand shape and the shape of an object to be grasped is used by observers to make sense of the details and cooperativeness of interpersonal actions (Shibata et al 2009). This emerging line of N400 work thus shows that motor and object features make early, parallel contributions to how an action is understood. Moreover,
