Laryngeal and vocal tract strategies to reduce vocal fold contact pressure

ABSTRACT Voice therapy remains the primary treatment option for phonotraumatic vocal hyperfunction, one of the most frequently occurring conditions to affect the voice. Voice therapy aims to modify hyperfunctional vocal behavior through vocal techniques or exercises, often with a focus on vibratory sensations in certain parts of the airway. It is generally believed that these techniques and exercises induce adjustments in the larynx and vocal tract that increase vocal efficiency and lower vocal fold contact pressure, an important contributing factor to vocal fold injury. However, such understanding is largely based on theoretical and numerical simulations, and there have been few experimental data supporting these hypotheses. Additionally, although voice therapy likely leads to multiple simultaneous laryngeal and vocal tract adjustments, information about the specific adjustments and their impact on vocal fold contact pressure is often vague. Currently, voice therapy outcomes are often evaluated based on patient-reported and other secondary measures. To date, no objective measures have been identified that would allow clinicians to reliably monitor and predict the progress of voice therapy with greater accuracy than is currently available. The goals of the proposed research are to (1) experimentally validate findings and hypotheses from previous numerical simulations on favorable laryngeal and vocal tract configurations that consistently reduce vocal fold contact pressures in excised human larynx experiments; and (2) investigate the effectiveness of voice therapy methods in reducing vocal fold contact pressures and in eliciting the hypothesized laryngeal and vocal tract configurations to do so, and the ability of these maneuvers to predict voice therapy outcomes.