Impaired access to manipulation features in Apraxia: evidence from eyetracking and semantic judgment tasks.

Apraxic patients are known for deficits in producing and comprehending skilled movements. Two experiments tested their implicit and explicit knowledge about manipulable objects in order to examine whether such deficits accompany impairment in the conceptual representation of manipulation features. An eyetracking method was used to test implicit knowledge (Experiment 1): participants viewed a visual display on a computer screen and touched the corresponding object in response to an auditory input.

Playing on the typewriter, typing on the piano: manipulation knowledge of objects.

Two experiments investigated sensory/motor-based functional knowledge of man-made objects: manipulation features associated with the actual usage of objects. In Experiment 1, a series of prime-target pairs was presented auditorily, and participants were asked to make a lexical decision on the target word. Participants made a significantly faster decision about the target word (e.