Features of Planned Hand Actions Influence Identification of Graspable Objects

We demonstrate that constituents of motor actions associated with handled objects play a role in identifying such objects. Subjects held in working memory action plans for reaching movements; these action plans specified both the hand to be used (left or right) and a wrist orientation (vertical or horizontal). Speeded object identification was impaired when a pictured object matched the action on only one of these two categorical dimensions (e.g., a beer mug with its handle facing left, an action plan involving the right hand and vertical wrist orientation), relative to when the object matched the action on both dimensions or neither dimension. This result implies that identification of a manipulable object leads to automatic retrieval of matching features of a planned action along with nonmatching features to which they are bound. These discrepant features conflict with those of the target object, which results in delayed identification.