Visual Short-Term Memory During Smooth Pursuit Eye Movements

Visual short-term memory (VSTM) was probed while observers performed smooth pursuit eye movements. Smooth pursuit keeps a moving object stabilized in the fovea. VSTM capacity for position was reduced during smooth pursuit compared with a condition with eye fixation. There was no difference between a condition in which the items were approximately stabilized on the retina because they moved with the pursuit target and a condition in which the items moved across the retina because they were stationary in space. The reduction of capacity for position was eliminated when miniature items were presented on the pursuit target. Similarly, VSTM capacity for color did not differ between smooth pursuit and fixation. The results suggest that visuospatial attention is tied to the target during smooth pursuit, which impairs VSTM for the position of peripheral objects. Sensory memory during smooth pursuit was only slightly impaired.