ROLE OF PERCEIVED MOTION IN SMOOTH PURSUIT EYE-MOVEMENTS

We examined responses of the smooth pursuit system under open-loop conditions: 1. (1) Subjects tracked an isolated target, oscillating sinusoidally at frequencies 0.3-1.5 Hz. When a variation of the Duncker illusion increased perceived target motion (leaving retinal target motion unaltered), pursuit responses increased. 2. (2) Measurements of perceived target motion during open-loop pursuit support the hypothesis that pursuit eye movements per se contribute to perceived motion. 3. (3) We interpret these results as evidence for a positive feedback loop in the pursuit system, related to perception. This loop may account for the high gain of the open-loop pursuit system. © 1979.