Robot Task. As in the MT, every trial began with a 500-msec visual instructional cue (“Grasp” or “Reach”). This was followed by a variable duration delay period lasting 2000, 2500, 3000, or 3500 msec, during which participants viewed a black screen with a small white fixation cross in the center (visible throughout the entirety of each run). The premovement phase included the 500-msec instructional cue and the first 3000 msec of the following delay period. Onset of the visual display served as the movement cue. The execution phase consisted of the 750-msec movement cue (“Go”, “Press”, or “Watch”) and the subsequent 6000 msec. See text for details.