Publications by Year: 2011

R. E. Hillman and D. D. Mehta, “Ambulatory monitoring of daily voice use,” Perspectives on Voice and Voice Disorders, vol. 21, no. 2, pp. 56-61, 2011. Publisher's Version Paper
S. S. Karajanagi, et al., “Assessment of canine vocal fold function after injection of a new biomaterial designed to treat phonatory mucosal scarring,” Annals of Otology, Rhinology, and Laryngology, vol. 120, no. 3, pp. 175-184, 2011. Publisher's Version Paper
D. D. Mehta, D. D. Deliyski, T. F. Quatieri, and R. E. Hillman, “Automated measurement of vocal fold vibratory asymmetry from high-speed videoendoscopy recordings,” Journal of Speech, Language, and Hearing Research, vol. 54, no. 1, pp. 47-54, 2011. Publisher's VersionAbstract

Purpose: In prior work, a manually derived measure of vocal fold vibratory phase asymmetry correlated to varying degrees with visual judgments made from laryngeal high-speed videoendoscopy (HSV) recordings. This investigation extended this work by establishing an automated HSV-based framework to quantify 3 categories of vocal fold vibratory asymmetry. Method: HSV-based analysis provided for cycle-to-cycle estimates of left-right phase asymmetry, left-right amplitude asymmetry, and axis shift during glottal closure for 52 speakers with no vocal pathology producing comfortable and pressed phonation. An initial cross-validation of the automated left-right phase asymmetry measure was performed by correlating the measure with other objective and subjective assessments of phase asymmetry. Results: Vocal fold vibratory asymmetry was exhibited to a similar extent in both comfortable and pressed phonations. The automated measure of left-right phase asymmetry strongly correlated with manually derived measures and moderately correlated with visual-perceptual ratings. Correlations with the visual-perceptual ratings remained relatively consistent as the automated measure was derived from kymograms taken at different glottal locations. Conclusions: An automated HSV-based framework for the quantification of vocal fold vibratory asymmetry was developed and initially validated. This framework serves as a platform for investigating relationships between vocal fold tissue motion and acoustic measures of voice function.

M. Döllinger, J. B. Kobler, D. A. Berry, D. D. Mehta, G. Luegmair, and C. Bohr, “Experiments on analysing voice production: Excised (human, animal) and in vivo (animal) approaches,” Current Bioinformatics, vol. 6, no. 3, pp. 286-304, 2011. Publisher's Version Paper
D. D. Mehta, S. M. Zeitels, J. A. Burns, A. D. Friedman, D. D. Deliyski, and R. E. Hillman, “High-speed videoendoscopic analysis of relationships between cepstral-based acoustic measures and voice production mechanisms in patients undergoing phonomicrosurgery,” Proceedings of the American Laryngological Association. 2011.
D. D. Mehta, M. Zañartu, T. F. Quatieri, D. D. Deliyski, and R. E. Hillman, “Investigating acoustic correlates of human vocal fold vibratory phase asymmetry through modeling and laryngeal high-speed videoendoscopy,” The Journal of the Acoustical Society of America, vol. 130, pp. 3999-4009, 2011.Abstract

Vocal fold vibratory asymmetry is often associated with inefficient sound production through its impact on source spectral tilt. This association is investigated in both a computational voice production model and a group of 47 human subjects. The model provides indirect control over the degree of left-right phase asymmetry within a nonlinear source-filter framework, and high-speed videoendoscopy provides in vivo measures of vocal fold vibratory asymmetry. Source spectral tilt measures are estimated from the inverse-filtered spectrum of the simulated and recorded radiated acoustic pressure. As expected, model simulations indicate that increasing left-right phase asymmetry induces steeper spectral tilt. Subject data, however, reveal that none of the vibratory asymmetry measures correlates with spectral tilt measures. Probing further into physiological correlates of spectral tilt that might be affected by asymmetry, the glottal area waveform is parameterized to obtain measures of the open phase (open/plateau quotient) and closing phase (speed/closing quotient). Subjects' left-right phase asymmetry exhibits low, but statistically significant, correlations with speed quotient (r=0.45) and closing quotient (r=-0.39). Results call for future studies into the effect of asymmetric vocal fold vibration on glottal airflow and the associated impact on voice source spectral properties and vocal efficiency.

D. D. Mehta, D. Rudoy, and P. J. Wolfe, “Joint source-filter modeling using flexible basis functions,” Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing, pp. 5888-5891, 2011. Paper
M. Zañartu, D. D. Mehta, J. C. Ho, G. R. Wodicka, and R. E. Hillman, “Observation and analysis of in vivo vocal fold tissue instabilities produced by nonlinear source-filter coupling: A case study,” The Journal of the Acoustical Society of America, vol. 129, pp. 326-339, 2011. Paper
D. D. Mehta, M. Zañartu, T. F. Quatieri, D. D. Deliyski, and R. E. Hillman, “Use of laryngeal high-speed videoendoscopy systems to study voice production mechanisms in human subjects,” Proceedings of the Acoustical Society of America, vol. 130, pp. 2439-2439, 2011.