Effects of Short-Term Mental Imagery and Supplemental Visual Feedback on Muscle Coordination in a Myoelectric Task.

Changing muscle coordination patterns is a critical part of motor learning - yet there is a lack of simple, clinically feasible techniques to alter these patterns. Here, we investigated the effects of short-term mental imagery and supplemental visual feedback on muscle coordination using a myoelectric reaching task with complex mapping of arm and hand muscles to cursor position. Forty participants were divided into four groups, and practiced this task over 180 trials. During a short intervention period, the controls rested, the task- and muscle-imagery groups were given specific instructions meant to simplify the task, and the supplemental feedback group was provided extra visual information of muscle-to-cursor mapping. Results showed that there were no changes in task performance between groups. However, we found that in terms of muscle coordination, the supplemental visual feedback group showed the most efficient coordination. Furthermore, across all groups, individuals with greater efficiency and exploration showed better task performance at the end of practice. The results from this pilot study point to a greater need for understanding strategies for changing muscle coordination, which could be applicable in a rehabilitation setting.