Graduation Year


Document Type




Degree Granting Department

Communication Sciences and Disorders

Major Professor

Ruth Huntley Bahr, Ph.D.

Committee Member

Bonnie Smith, Ph.D.

Committee Member

Darla Freeman LeVay, M.A.


breathing exercises, essential tremor, laryngeal lowering, neurologic voice disorders, spirometer


Essential voice tremor (EVT) is a voice disorder that results from dyscoordination within the laryngeal musculature, which negatively impacts the symmetrical motion of the vocal folds. Several investigators have shown that individuals with EVT experience difficulty speaking and a reduced quality of life (QOL; Cohen, Dupont, & Courey, 2006; Verdonck-de Leeuw & Mahieu, 2004). While traditional voice therapy has been ineffective in lessening the severity of vocal tremor, a current approach (Barkmeier- Kraemer, Lato, & Wiley, 2011) designed to lessen the perception of vocal tremor has resulted in reported patient satisfaction with little actual change in voice quality. The present study focused on achieving positive voice changes by targeting the physiological aspects of voice production that may be altered through inspiratory breathing techniques, i.e., increased lung volume pressure and laryngeal lowering. The hypothesis was that such changes could result in reductions in vocal tremor and lead to perceived improvements in voice quality and concomitant increases in the participant's QOL.

An ABAB (treatment reversal) single subject design was used to assess the effectiveness of inspiratory breathing exercises on reducing the severity of tremor in three women diagnosed with EVT. Pre-treatment measures were administered, and participant progress was determined after one week of treatment (post-treatment #1), a week of no treatment, and another week of treatment (post-treatment #2). The following measures were gathered from each participant to document treatment progress and effectiveness:lung pressure volume levels, Voice Handicap Index (VHI) ratings, acoustic analyses of isolated vowels, and perceptual ratings on the Consensus Auditory Perceptual Evaluation of Voice (CAPE-V), as well as untrained listener ratings of vocal steadiness and pleasantness.

Physiological, QOL, acoustic, and perceptual data did not triangulate to demonstrate treatment effectiveness. However, individual treatment effects were found in increases in lung pressure volume for participant 1, decreases in CAPE-V scores for participant 3, and decreases in VHI scores for participants 1 and 3. Changes in voice acoustics and untrained listener perceptions were negligible. Thus, the results from this study indicate that inspiratory breathing exercises may show some promise in improving voice and QOL in certain tremor patients and that this technique warrants further research consideration.