Preventing late corrections reveals anticipatory motor control

Abstract

Abstract

Successful interception requires combining predictive planning with continuous sensory feedback, yet these processes are difficult to dissociate because they operate simultaneously throughout movement. Here, we asked how predictive control is expressed when late online corrections are made ineffective but visual information is left intact. Participants performed a visuomotor interception task in which they moved a horizontal cursor to intercept a falling target at its predicted landing position. On selected trials, the cursor became temporarily unresponsive immediately before interception, preventing late motor corrections while leaving the target continuously visible. Manual and gaze behavior were quantified using two complementary root-mean-square error (RMSE) measures that tracked alignment with either the target’s instantaneous position or its landing position. Under normal conditions, manual movements converged on the predicted landing position earlier on successful than on unsuccessful trials; trial-averaged gaze showed no comparable effect. Increasing cursor-freeze durations progressively reduced interception accuracy but shifted manual behavior toward earlier alignment with the landing position before the freeze began, indicating a redistribution of control from late feedback corrections toward earlier predictive planning. These findings show that when late online corrections become ineffective, humans compensate by committing earlier to predicted future states. This redistribution was large and consistent in manual behavior, and considerably harder to detect in trial-averaged gaze.