Objectives: Despite anecdotal reports of voice impairment in quadriplegia, the exact nature of these impairments is not well described in the literature. This article details objective and subjective voice assessments for people with quadriplegia at baseline and after a respiratory-targeted singing intervention.
Study design: Randomized controlled trial.
Methods: Twenty-four participants with quadriplegia were randomly assigned to a 12-week program of either a singing intervention or active music therapy control. Recordings of singing and speech were made at baseline, 6 weeks, 12 weeks, and 6 months postintervention. These deidentified recordings were used to measure sound pressure levels and assess voice quality using the Multidimensional Voice Profile and the Perceptual Voice Profile.
Results: Baseline voice quality data indicated deviation from normality in the areas of breathiness, strain, and roughness. A greater percentage of intervention participants moved toward more normal voice quality in terms of jitter, shimmer, and noise-to-harmonic ratio; however, the improvements failed to achieve statistical significance.
Conclusions: Subjective and objective assessments of voice quality indicate that quadriplegia may have a detrimental effect on voice quality; in particular, causing a perception of roughness and breathiness in the voice. The results of this study suggest that singing training may have a role in ameliorating these voice impairments.
Keywords: Intensity; Music therapy; Quadriplegia; Singing; Spinal cord injury; Voice quality.
Copyright © 2014 The Voice Foundation. Published by Mosby, Inc. All rights reserved.