Previous studies have demonstrated that observing another’s hand-grasping action modulates the observer’s attention to the object that is congruent with the size of the aperture of the hand. In this study, we investigated whether observing tool grasping also modulates the observer’s attention. On a simple detection task, pictures of two objects (small and large object) and a hand or a tool were presented on a screen. Then, the hand or the tool was shown in either a precision grip (to grasp the small object) or a power grip (to grasp the large object), followed by a target presented either over the small object or over the large object. The results indicate that participants detected the target presented over an object that is congruent with
