Sensitivity of Smooth Eye Movement to Small Differences in Target Velocity

摘要

The precision of smooth pursuit eye movements was described by means of a new dependent measure, the 'oculomotor difference threshold' which represents the smallest difference in target velocity that produces statistically distinguishable differences in eye velocity. Oculomotor difference thresholds for constant velocity motions were largest during the initial 200 msec of target motion, despite fairly high average gains during the same period. Oculomotor difference thresholds declined over time. By about 600-700 msec after the onset of target motion they reached values a low as the perceptual difference thresholds measured psychophysically with the same target velocities. Nonsensory influences on smooth eye movement were also found.