Fig. 2.

Apparatus used to introduce limited visuomotor remappings. The position of the finger was captured on-line by a computer, which calculated the perturbed finger position. The feedback of finger position was projected onto a screen as a cursor spot. Looking down at the mirror, the subjects saw the virtual image of the cursor spot, in the plane of the finger—the actual finger location was hidden from view. By controlling the illumination of the cursor spot, the visual feedback, and therefore the remapping, could be limited to particular areas of the workspace.