Influence of movement kinematics on visuomotor adaptation.

It is still unknown whether visuomotor adaptation depends on the time during which a person is exposed to distorted vision, or rather on the number of movements executed under the distortion. To find out, we analysed the pointing errors and movement kinematics of 52 participants adapting with online visual feedback to a 60° visual rotation and 39 participants adapting to a 75° visual rotation without time constraints. We found that movement time was not related with participants' success during adaptation, whereas peak velocity was inversely associated to adaptive success. However, peak velocity lost its association to adaptation when other parameters were taken into account. Movement kinematics during adaptation had little influence on participants' performance during de-adaptation. Our data suggest that adaptation does not depend primarily on the duration but rather on the number of movements executed under distorted vision. It further suggests that the measured kinematic parameters are consequences of error corrections rather than determinants of the adaptive success. We further have evidence for the view that adaptive recalibration is independent of movement kinematics during adaptation. This outcome generalizes across different visual rotations and is in accordance with earlier work where online visual feedback of the hand was unavailable.