On the influence of laryngeal pathologies on acoustic and electroglottographic jitter measures

Abstract

This study compared acoustic and electroglottographic (EGG) jitter from [a] vowels of 103 dysphonic speakers. The EGG recordings were chosen according to their intensity, signal-to-noise ratio, and percentage of unvoiced intervals, while acoustic signals were selected based on voicing detection and the reliability of jitter extraction. The agreement between jitter measures was expressed numerically as a normalized difference. In 63.1% (65/103) of the cases the differences fell within +/-22.5%. Positive differences above +22.5% were associated with increased acoustic jitter and occurred in 12.6% (13/103) of the speakers. These were, typically, cases of small nodular lesions without problems in the posterior larynx. On the other hand, substantial rises in EGG jitter leading to differences below -22.5% took place in 24.3% (25/103) of the speakers and were related to hyperfunctional voices, creaky-like voices, small laryngeal asymmetries affecting the arytenoids, or small-to-moderate glottal chinks. A clinically relevant outcome of the study was the possibility of detecting gentle laryngeal asymmetries among cases of large unilateral increase in EGG jitter. These asymmetries can be linked with vocal problems that are often overlooked in endoscopic examinations.

Updating signal typing in voice: Addition of type 4 signals

“…Titze ͑1995͒ recommended spectrographic and perceptual analysis methods for type 2 and type 3 voices. Today, Titze's ͑1995͒ recommendations continue to be employed to determine the suitability of voice signals for perturbation analysis ͑Bielam-owicz et al, 1996;Vieira et al, 2002;Shaw and Deliyski, 2008;Zhang and Jiang, 2008͒. The task of analyzing type 2 and 3 signals has fallen to spectrograms, perceptual analysis, and, more recently, nonlinear dynamic analysis.…”

“…Despite the improvements afforded by nonlinear analysis, many of its parameters are negatively impacted by infinite dimensionality ͑Little et al, 2007͒. This behavior is commonly interpreted as phonation breathiness and is especially common in disordered voices ͑Herzel et al, 1994;Vieira et al, 2002;Zhang et al, 2005a. Because of the turbulence surrounding the airflow jet from which voice is produced, all voices are associated with noise that has an infinite dimension ͑Jiang and Zhang, 2002;Krane, 2005͒ et al, 1998;Goode et al, 2001;Zhang et al, 2004;Little et al, 2007͒.…”

Técnica de Horsley para la reconstrucción del nervio laríngeo

“…El análisis acústico de la voz fue realizado por una fonoaudióloga, e incluyó el tiempo máximo de fonación (segundos), el índice de jitter (%), el índice de shimmer (dB) y la frecuencia fundamental (Hz) 5,6 . La estroboscopia fue practicada por un laringólogo, e incluyó el cierre glótico (completo o incompleto), la posición de los cartílagos aritenoides y la anatomía de las cuerdas vocales.…”

Análisis acústico de la voz normal y patológica utilizando dos sistemas diferentes: ANAGRAF y PRAAT

“…Las medidas de jitter se relacionan con la variación en el corto plazo: el jitter mide cuánto difiere un período dado del período que lo sucede inmediatamente (Lieberman, 1961). Es importante considerar que se han reportado importantes diferencias de aproximadamente el 22.5% en la estimación del jitter a partir de la señal acústica y la electroglotográfica (Vieira, McInnes & Jack, 1996, 2002.…”