The effects of self-controlled feedback on learning of a "relaxed phonation task".

Background: This study examined the effects of self-controlled feedback paradigm on motor learning of a relaxed phonation task. It investigated whether providing the learner with more control over practice condition has positive influences on the performance and learning of "relaxed phonation" skill.

Methods: Vocally healthy individuals were randomly assigned into either self-controlled feedback group (SELF) or clinician-controlled feedback group (YOKED). All participants were engaged in a reading aloud task. Throughout the task, their perilaryngeal muscle activities were measured at thyrohyoid (TH) and orofacial (OF) sites using surface electromyography (EMG). The EMG values measured at the TH site were provided to participants as terminal biofeedback. Participants were required to minimize the EMG values. The SELF group received EMG biofeedback whenever they requested it, whereas the YOKED group received the same feedback schedule as chosen by their self-controlled counterparts.

Results And Discussion: The pooled data for all participants revealed that there was a significant reduction of muscle tension across baseline, training, and retention phases. Generalization was shown to reading of untrained passage. Interestingly, significant reduction of muscle tension across training and retention tests was found in the control OF site but not in the target TH site. The results failed to demonstrate significant differences between SELF and YOKED groups. It provided no clear evidence to conclude that self-controlled feedback paradigm was beneficial to learning of relaxed phonation.