Adaptation to novel visuo-motor transformations: further evidence of functional haptic neglect.

Studies with perturbed and augmented haptic information during adaptation to novel visuo-motor transformations suggest that haptic information might be neglected. However, the notion of functional haptic neglect during adaptation is counterintuitive for different reasons. Therefore, we sought conditions where haptic guidance during adaptation results in benefits. First, we mixed guided and unguided trials during practice with a visuo-motor rotation. In two experiments, we found no indication of an advantage of the guidance groups over the no-guidance control groups. In the third experiment, the visuo-motor transformation was a pure time delay because motor timing has been hypothesized to profit from haptic guidance. Again, there was no evidence of benefits for the guidance group. Thus, the findings of this series of experiments provide further evidence of the claim that haptic information is neglected during adaptation to a visuo-motor transformation.