Stimuli and experimental design.
A. Exemplars of the used stimuli. 1: No context condition. Participants observed two pictures in sequence. The first showed an object (e.g., a cup) without any context, the second a hand interacting with that object. Three types of hand-object interactions were presented: a hand grasping the object as for using it (Ug); a hand grasping an object as for moving it (Tg); a hand touching an object without any obvious purpose (Sc). 2: “Context” condition. As in the previous condition, participants saw two pictures in sequence. The first showed an object embedded in a context (upper row). The second one showed a hand grasping that object. The context allowed the observer to decide whether the agent's intention was to use the object or to move it (U and T, middle row). A simple contact of the hand with the object was also presented in both the contexts (Usc: use context, simple contact; Tsc; transport context, simple contact; upper right, lower row). B. Procedure. Each trial consisted of the following sequence: fixation cross; object alone or within a context hand-object interaction; fixation cross. The sequence shown in figure illustrates the use grip (Ug) in No context condition.