Abstract
Visuomotor adaptation is often sufficient to resolve movement errors caused by sensorimotor perturbations, but certain kinds of perturbations cause errors that cannot be resolved by adaptation. We hypothesized that these unresolvable errors would be effective in changing 3D perception. In two experiments, participants provided perceptual estimates of stereo-texture surface slants before and after repetitive visuomotor interactions with cue-conflict surfaces where haptic feedback was always consistent with texture. The visuomotor task was to reach toward the target surfaces with a precision grip, orienting the grip so that the finger and thumb would make contact simultaneously. In Experiment 1, participants aimed at three different cue-conflict surfaces, each having a texture-specified slant 30° deeper than its stereo-specified slant. Terminal grip orientations initially targeted the intermediate perceived slants, but were adjusted toward the consistently deeper physical slants over time, demonstrating successful visuomotor adaptation. By including a washout phase where the cue-conflict slants were replaced with perceptually matched cue-consistent slants, we verified that the change was due to standard visuomotor adaptation, as opposed to an increased weight on texture information for grip orientation. As predicted for successful adaptation, we observed no change in slant perception. In Experiment 2, we presented a variety of cue-conflict surfaces. For some, the haptically reinforced slant was flatter than the perceived slant; for others, it was deeper than perceived. Due to interference between these opposing perturbations, visuomotor adaptation failed to resolve the movement errors. As predicted for unsuccessful adaptation, the pattern of changes in slant perception for the cue-conflict surfaces matched the pattern of experienced movement errors. Additionally, we found that cue-consistent surfaces were perceived as flatter. Our findings show that when limitations on visuomotor adaptation allow movement errors to persist, 3D visual perception changes. This suggests that visuomotor and 3D perceptual processes share the goal of supporting accurate movement.
Meeting abstract presented at VSS 2018