The Effects of Respiratory Training on Voice

Primary muscle tension dysphonia is a voice disorder that involves excessive and poorly coordinated muscle activity affecting multiple subsystems that are involved in speech production, in the absence of structural or neurologic abnormalities of the larynx. Primary muscle tension dysphonia (MTD) is one of the most common forms of voice disorders, accounting for at least 40% of patients seen in voice clinics. Perceptually the voice sounds hoarse and strained, with reduced loudness and pitch range, and people with MTD find speaking very effortful and fatiguing. The physiological abnormalities that characterize MTD are considered multifactorial, and include over-activity of muscles in and around the larynx, laryngeal constriction patterns, and abnormal speech breathing patterns. However, standard treatment approaches for MTD primarily address laryngeal function, including repositioning of laryngeal structures, reducing activity in the intrinsic and extrinsic laryngeal muscles, and altering vibratory patterns. Although voice improvement may follow these treatments, many people with MTD show recurrence of voice problems after only a few months, and some do not improve with treatment. These findings highlight the need for alternative treatments that address the respiratory contributions to MTD, which directly affect the phonatory system. The goal of this project is to compare the effects of two respiratory-based training conditions in people with MTD. A randomized group design will be implemented to determine the respiratory and acoustic effects of each condition. We will determine the effects of each condition immediately after and then 3 and 6 months after training completion to assess short- and long-term training effects. We propose that respiratory training will have a positive effect on related laryngeal behavior and voice. The proposed project has the potential to substantially advance the evidence-based treatment options for MTD, providing a vital step toward reducing the debilitating effects of this disorder.