Comparing Measures of Voice Quality From Sustained Phonation and Continuous Speech

Abstract

Purpose:The question of what type of utterance-a sustained vowel or continuous speech-is best for voice quality analysis has been extensively studied but with equivocal results. This study examines whether previously reported differences derive from the articulatory and prosodic factors occurring in continuous speech versus sustained phonation. Method: Speakers with voice disorders sustained vowels and read sentences. Vowel samples were excerpted from the steadiest portion of each vowel in the sentences. In addition to sustained and excerpted vowels, a 3rd set of stimuli was created by shortening sustained vowel productions to match the duration of vowels excerpted from continuous speech. Acoustic measures were made on the stimuli, and listeners judged the severity of vocal quality deviation. Results: Sustained vowels and those extracted from continuous speech contain essentially the same acoustic and perceptual information about vocal quality deviation. Conclusions: Perceived and/or measured differences between continuous speech and sustained vowels derive largely from voice source variability across segmental and prosodic contexts and not from variations in vocal fold vibration in the quasisteady portion of the vowels. Approaches to voice quality assessment by using continuous speech samples average across utterances and may not adequately quantify the variability they are intended to assess.

The Effect of the Speech Task Characteristics on Perceptual Judgment of Mild to Moderate Dysphonia: A Methodological Study

“…Secondly, the rating of the individual components of the perceptual voice quality (G, R, B, A, S, and I) may be tougher on a “static” vocal task (sustained vowel) unlike the revealing nature of connected speech. It has been shown that connected speech provides more apparent and dynamic signals than sustained vowel (related to the greater laryngeal muscular movement and the impact on the pitch, loudness, and tessitura), which remains more reliable to judge [10, 13, 33]. Interestingly, the recent paper of Gerratt et al [33] proposed that the perceptual differences between sustained vowel and continuous speech derived from the variability of voice source across segmental and prosodic contexts and not from variations of the vocal cord vibration in the quasi-steady portion of the vowel [21].…”

Effect of vowel context in cepstral and entropy analysis of pathological voices

“…Running speech on the other hand commonly occurs in real life situations, i.e., it is a natural and ecologically valid signal that could serve as a basis for perceptual assessment and acoustic analysis [2]. Using running speech though is not as straightforward as using sustained vowels, since the voiced parts of speech are rather short, and the phonetic context of the vowels can affect objective voice quality measures [3].…”

“…Several earlier studies have investigated how different perceptual or acoustic measures depend on the vowel context [3][4][5][6].…”

“…Gerratt et al [3] concluded that when analyzing or evaluating perceptually either sustained vowels or vowels excerpted from continuous speech, the information on deviation from normal voice quality was the same. The aim of the present study is to investigate how vowel context (sustained versus excerpted) affects the predictive power for dysphonia of two objective voice quality measures, i.e., the cepstral peak prominence smoothed (CPPS) and the sample entropy (SampEn).…”

A Study on the Aerodynamic Characteristics of Sustained Vowel and Continuous Speech Production of Female Voice Disorder Patients

“…음성장애 성인 여성화자의 연장모음 및 연속발화 산출 시 공기역학적 특성 연구 • 표화영 MPT)이나 평균호기율(mean flow rate, MFR) 등을 측정한다. 연장 모음으로 기기적 평가를 실시하면 검사시간이 짧고 억양, 강세, 말 속도 등의 영향을 받지 않으며 방언의 영향을 덜 받는다는 장점이 있다 (Gerratt, Kreiman, & Garellek, 2016 MPT-V = maximum phonation time-vowel; PEA-V = peak expiratory airflow-vowel; MEA-V = mean expiratory airflow-vowel; EV-V = expiratory volume-vowel; PT-C = phonation time-continuous speech; TD-C = total duration-continuous speech; EAD-C = expiratory airflow duration-continuous speech; IAD-C = inspiratory airflow duration-continuous speech; PEA-C = peak expiratory airflow-continuous speech; PIA-C = peak inspiratory airflow-continuous speech; EV-C = expiratory volume-continuous speech; IV-C = inspiratory volume-continuous speech. *p < .05, **p < .01.…”