Figure 1.

Task. A, Stimuli. Plastic casts of hands, teapots, and toy cars were used as stimuli. An alphabetic code (a–d) was assigned to the four exemplars of each object category. B, Haptic task. Subjects were instructed to explore the object with their right hand immediately after they heard a sound cue through headphones. When a second sound cue was presented (after 7.5 s of exploration), the subjects were told to stop. They were instructed to respond by using their left hand to press the button corresponding to the appropriate alphabetic code. C, Visual task. Sighted subjects were instructed to identify the four exemplars of each object category by pressing the same buttons as used in the haptic task. For both haptic and visual tasks, neural activity during the task block was modeled with a boxcar function for each object category. The regressor shown was convolved with a canonical hemodynamic response function.