Development and Evaluation of a Portable Visual Feedback System for Vocal Training through Tube Phonation

Abstract

Tube phonation is a semi-occluded vocal tract exercise used for vocal training in patients with voice disorders. During tube phonation, focus is placed on the vibratory sensations around the lips, as they may help the patient find the optimal glottal and upper larynx settings. However, it is difficult to monitor the magnitude of a patient's vibratory sensations during tube phonation and judge the practice's accuracy objectively. This study therefore proposed a portable visual feedback system, "Smart Tube," that can measure the amplitude and fundamental frequency of the vibrations of the tube and provide corresponding feedback through LED lights in real time. During a three-month evaluation of the system for a patient with voice disorders, the system was used continuously and demonstrated good usability. The visual feedback by LED clearly indicated the objective of the home practice as well as its accuracy; moreover, the practice had a positive effect on the patient's mental wellbeing. These results suggest that Smart Tube can facilitate sharing of a mutual understanding between the patient and the speech-language-hearing therapist and become a useful tool for conducting continuous tube phonation at home.