Figure 5.

Effect of the distance from the endpoint of the saccade to the target position on the relationship between postsaccadic eye velocity and target speed. A, Schematic diagram showing the task as a sequence of four snapshots in time. A1, A target (open circle) began moving at the fixation point at 20°/s. A2, The target stepped and moved at a speed indicated by the marker: 10°/s (black filled circle), 20°/s (open circle), or 30°/s (gray circle). Only one target was visible to the monkey on the trial. The eye (x) begins pursuit in the direction of initial target motion. A3, The eye makes a saccade to the old location of the target and moves in the same direction. Only the 20°/s target is shown for clarity. A4, The eye makes a saccade to the new location of the target and tracks it appropriately. B, Four graphs plotting the mean and SD of the absolute value of postsaccadic eye velocity against the distance between target and eye, for three different speeds of target motion. Different axes and markers correspond to different monkeys. Black-filled markers are trials in which the target slowed to 10°/s, open markers are ones in which the target continued to move at 20°/s, and gray-filled markers are ones in which the targets sped up to 30°/s.