Abstract
The human motor system can adapt to unexpected perturbations during ongoing movements. Except for target jump studies, most of the research focused on adaptation to perturbations applied to the hand, such as force field or visuomotor rotation. But less is known about how we adapt to perturbations affecting objects that we interact with. For instance, do participants take into consideration visual cues in the environment to reduce their errors and correct subsequent motor commands? To investigate this question, we used an online version of the pong game in which participants intercepted a ball using a paddle controlled by their cursor. We manipulated the post-bounce ball trajectory to be congruent or not with the orientation of the bouncing wall. The “trained tilt” group (n = 34) adapted to the congruent condition while the “trained horizontal” group (n = 36) adapted to the incongruent condition. If visual cues are effectively used by participants, the “trained tilt” group should exhibit faster and/or more complete adaptation than the “trained horizontal” group. Our results showed that the perturbation significantly decreased the interception success rate. Both groups showed typical markers of motor adaptation: large initial errors upon perturbation introduction, followed by rapid error reduction and aftereffects (errors in the opposite direction) when the perturbation was removed. However, we did not observe significant differences in interception success rates or errors between the “trained tilt” and “trained horizontal” groups. Our findings suggest that participants quickly adapted to the dynamics of the pong ball although the tilt of the bouncing surface did not contribute to their performance. Furthermore, this experiment provides evidence that adaptation to external perturbations applied to a moving object is possible in online settings. These results encourage further research on motor adaptation using more naturalistic stimuli and gamified tasks, in real-world or virtual reality environments.