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Published on: November 25, 2017
Vowel harmonic amplitude differences in persons with vocal nodules
B Radish Kumar1, Jayashree S Bhat, Payal Mukhi
1Department of Audiology and Speech Language Pathology, Kasturba Medical College (A Unit of Manipal University), Mangalore, Karnataka, India. radheesh_b@yahoo.co.in
Journal of Voice : Official Journal of the Voice Foundation
|October 8, 2010
Summary
Individuals with vocal nodules exhibit altered vocal harmonic amplitudes. This acoustic measure, derived from the power spectrum, may help track treatment progress in voice disorders.
Area of Science:
- Acoustic analysis of voice production
- Speech pathology and audiology
Background:
- The power spectrum, generated via Fast Fourier Transform, quantifies glottal function.
- Abnormalities in higher harmonic amplitudes relative to the first harmonic may indicate vocal fold dysfunction.
Purpose of the Study:
- To investigate differences in vowel harmonic amplitudes between individuals with and without vocal nodules.
- To determine if acoustic measures can differentiate vocal nodule patients.
Main Methods:
- 120 participants were divided into clinical (vocal nodules) and control groups.
- Participants phonated /a/, and acoustic signals were analyzed using Fourier transformation.
- Harmonic amplitudes (H1, H2) and formant amplitudes (A1, A2, A3) were measured.
Main Results:
- Significant differences (P<0.05) were found between groups for H1-H2, H1-A1, H1-A2, and H1-A3.
- These acoustic parameters reflect underlying pathophysiology in vocal nodules.
Conclusions:
- Vocal harmonic amplitude differences are significantly altered in individuals with vocal nodules.
- This acoustic measure shows potential for monitoring therapeutic changes in voice treatment.
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