Acquisition of self-control of a novel muscular activity with EMG and video feedback.

To examine the acquisition of voluntary control of a novel muscular activity from the initial stage to the self-control stage, the m. auricularis posterior, which had generally degenerated and had nearly lost its function of drawing an auricle backward in the human body, was selected as a target muscle to be studied. One female undergraduate student who could not move her auricles intentionally was required to activate her left m. auricularis posterior and underwent rest, pretest, training, and posttest sessions once a day for five days. At the subject's request, the electromyograph (EMG) from her left m. auricularis posterior on an oscillograph was provided for her as the feedback signal on each training trial. The picture of her left ear on television was handled in the same way. The EMG measures indicated that the subject could learn to activate her left m. auricularis posterior differentially. The number of training trials on which the subject requested the feedback signals suggested that EMG feedback signal was more useful to her than the video and that the usefulness of the feedback signals varied as the training sessions advanced. It was also concluded from analysis of the self-report data that the acquisition process of self-control of a novel muscular activity could be divided into at least four stages.