Voice ambulatory biofeedback has the potential to significantly improve voice therapy effectiveness by targeting the hardest aspect of rehabilitation - carryover outside the therapy session (also known as retention or learning). While there is initial evidence that ambulatory biofeedback can alter vocal behavior (using simple pitch and loudness thresholds) when the biofeedback is present (i.e., a biofeedback effect), there have been no well-designed studies demonstrating the persistence of a vocal behavior change once the biofeedback was turned off. Meaning ambulatory biofeedback has demonstrated the ability to only temporarily modify a subject's vocal behavior, not enact a longer term change or retention/learning. According to motor control and learning literature, two aspects of biofeedback delivery will improve vocal motor learning: (i) decreased frequency of cueing (e.g., providing feedback every 2nd time exceeding threshold instead of every time) and (ii) average summary feedback (e.g., providing the percent correct over a time period). Furthermore, average summary feedback has the potential to provide positive feedback if the subject receives a high percentage - which is also known to strengthen retention. In order to apply (i) and (ii) in an ambulatory manner, more advanced platforms for monitoring and biofeedback are needed than are currently available. We recently developed a smartphone-based voice ambulatory monitor (named the Voice Health Monitor -VHM) for use in another NIH-funded study that also has biofeedback capabilities. The VHM will be used in the proposed project to provide three different structures of ambulatory biofeedback in order to decrease a subject's vocal loudness throughout the day. A control group (group 1) will be provided ambulatory biofeedback every time they voice louder than a biofeedback threshold, a second group (group 2) will be provided ambulatory biofeedback every fourth time they voice louder than a biofeedback threshold, and a third group (group 3) will be provided summary average statistics regarding their compliance below a biofeedback threshold every 20 minutes. It is hypothesized that decreased frequency (group 2) and summary average feedback (group 3) will result in better retention of the desired softer phonation when biofeedback is turned off compared to the control group.
Voice ambulatory biofeedback has the potential to significantly improve voice therapy effectiveness by targeting the hardest aspect of rehabilitation - carryover outside the therapy session (also known as retention). This project will use ambulatory biofeedback structures based on motor control and learning theory to attempt to improve the retention of modified vocal behaviors (decreased vocal loudness) in subjects with normal voices. Specifically, decreased frequency of feedback and summary average feedback schedules will be empirically compared to immediate 100% feedback regarding their effects on subject performance, short term retention, and long term retention.
