Evocation of functional and volumetric gestural knowledge by objects and words.

We distinguish between grasping gestures associated with using an object for its intended purpose (functional) and those used to pick up an object (volumetric) and we develop a novel experimental framework to show that both kinds of knowledge are automatically evoked by objects and by words denoting those objects. Cued gestures were carried out in the context of depicted objects or visual words. On incongruent trials, the cued gesture was not compatible with gestures typically associated with the contextual item. On congruent trials, the gesture was compatible with the item's functional or volumetric gesture. For both gesture types, response latency was longer for incongruent trials indicating that objects and words elicited both functional and volumetric manipulation knowledge. Additional evidence, however, clearly supports a distinction between these two kinds of gestural knowledge. Under certain task conditions, functional gestures can be evoked without the associated activation of volumetric gestures. We discuss the implication of these results for theories of action evoked by objects and words, and for interpretation of functional imaging results.