Overcoming the guidance effect in motor skill learning: feedback all the time can be beneficial.

Extensive research has shown that augmented feedback presented too often can create a dependency on the feedback and hinder long-term memory formation of a motor skill. This dependency has been labeled the guidance effect, and one way to overcome the guidance effect is to reduce how often augmented feedback is presented during training. In two experiments, participants were presented with visual augmented feedback during every trial in a 5-min training interval. Participants were provided visual augmented feedback in the form of a Lissajous template of a 1:2 multi-frequency pattern and a cursor representing the coordination between the limbs. Some participants were trained with the cursor superimposed (behind group) on the Lissajous template, and others were trained with the cursor presented in a separate window (side group) from the Lissajous template. In experiment 1, motion of the end-effectors was constrained to the medial-lateral direction in the horizontal plane. In experiment 2, end-effector motion was possible in both the medial-lateral and anterior-posterior directions in the horizontal plane. The location of the cursor did not influence performance during the 5-min training interval in either experiment. After a 15-min break, a retention test performed without the visual feedback provided by the cursor revealed that the behind groups' performance was guided by the visual feedback in both experiments, whereas the side groups were able to perform without visual feedback. In experiment two, the side group's performance without feedback was influenced when anterior-posterior motion was not constrained; however, the extent of the guidance effect was significantly less compared to the behind trained group in both experiments. The results show that the emergence of guided motor performance depends on the format of the display that provides visually based augmented feedback, and not just on how often the feedback is provided. In conclusion, visually based augmented feedback leads to the simultaneous development of a spatial and motor representation of the task. The behind format led to a dependence on the spatial representation developed during training, while the side format facilitated the development of the motor representation as a means to overcome guidance.