Sustained Vowel Phonation Research Articles

Contributions of auditory feedback frequency components on F0 fluctuations

Auditory feedback effects on voice F0 control were investigated in terms of the frequency range of feedback harmonic components. The analysis was based on data obtained by a new experimental auditory feedback method called TAF (transformed auditory feedback). This method replaces a natural side tone path with an artificial path which modifies the parameters of the feedback speech sounds in real time, and measures effects in the speech sounds produced [Kawahara and Williams, Vocal Fold Physiology Symposium (1995)]. A series of TAF experiments using sustained vowel phonations with band limitations using high-pass and low-pass filters was conducted. Estimated impulse responses from pitch perception to voice F0 control illustrated that the response is compensatory and can be decomposed into two second-order responses with an initial delay. The results indicated that high-pass filtering does not show significant effects on response parameters while low-pass filtering shows a negative correlation between the cutoff frequency and the response delay. The average response delays for high-pass filtering and low-pass filtering were equivalent for a 800-Hz cutoff frequency. Implications on voice pitch perception will be discussed.

Aerodynamic mechanisms underlying treatment-related changes in vocal intensity in patients with Parkinson disease.

The purpose of this study was to document changes in aerodynamic and glottographic aspects of vocal function in patients with Parkinson disease who received two forms of high effort treatment. Previous reports (Ramig, Countryman, Thompson, & Horii, 1995) have documented increased sound pressure level (SPL) following treatment that trained phonation and respiration (Lee Silverman Voice Treatment: LSVT), but not for treatment that trained respiration only (R). In order to examine the mechanisms underlying these differences, measures of maximum flow declination rate (MFDR) and estimated subglottal pressure (Psub) were made before and after treatment. A measure of relative vocal fold adduction (EGGW) was made from the electroglottographic signal during sustained vowel phonation. Sound pressure level data from syllable repetition, sustained vowel phonation, reading, and monologue tasks were also analyzed to allow a more detailed understanding of treatment-related change in several contexts. Consistent with increases in SPL, significant increases in MFDR, estimated Psub, and EGGW were measured posttreatment in patients who received the LSVT. Similar changes were not observed following R treatment. These findings suggest that the combination of increased vocal fold adduction and subglottal pressure is a key in generating posttreatment increases in vocal intensity in idiopathic Parkinson disease (IPD).

The effect of intensive voice therapy on speech and voice deficits in atypical Parkinson’s disease

Acoustic data were collected twice pre‐treatment, once post‐treatment, and 6 months post‐treatment on three atypical Parkinson’s disease patients following intensive voice therapy. Using a custom‐built software program, the following variables were measured: maximum duration of sustained vowel phonation and sound pressure level from sustained vowel phonation, a standard passage, and spontaneous speech. Using the C‐Speech application [Milenkovic, J. Speech Hear. Res. 30, 529–538 (1987)], fundamental frequency variability was measured from a standard passage and spontaneous speech. Single‐word intelligibility was calculated using naive listeners’ perceptions. The patients achieved statistically significant improvement on all variables post‐treatment but did not maintain improvement as a group during reading and spontaneous speech by the 6‐month data collection session. These results suggest the effectiveness of intensive voice treatment in atypical Parkinson’s disease as well as provide insight into the und...

Aerodynamic assessment of the speech of adults undergoing multichannel cochlear implantation.

This investigation was designed to evaluate the aerodynamic characteristics of the speech of adult multichannel cochlear implant (Nucleus, 21-channel) recipients. Five adults with an acquired profound sensorineural hearing loss were tested before implantation, immediately following implantation, and 3, 6, 9, and 12 months after implantation. A commercially available computerized pressure-flow instrumentation system was employed to assess the respiratory, laryngeal, velopharyngeal, and oral articulatory subsystems of speech of the implantees. The results of the investigation indicated 1) a slight increase in airflow rate values for sustained vowel /a/phonation after implantation, 2) a slight increase in duration of sustained vowel phonation from the preimplant period to the last postimplant period, 3) an increase in laryngeal airway resistance after implantation that resulted from a larger increase in estimated transglottal pressure than in transglottal airflow, 4) maintenance of normal velopharyngeal closure in oral-nasal contrastive contexts, and 5) slight increases in oral orifice area for fricative syllable utterances following implantation. Individual strategies for coordinated control of the speech mechanism appear to be potent variables to consider when assessing speech production.

母音持続発音時における下顎位の動態について

母音持続発音時における下顎位の動態について

声の老化-発声機能からみた老化と下気道-

In order to evaluate the phonatory function causing by senescence of the larynx, normal adult subjects (52 males and 45 females) were examined the aerodynamic aspects and acoustic analysis for their sustained vowel phonation, and also we measured their pulmonary function test at the same time. The parameters for phonatory function were applied the Maximum sustained phonation time (M.P.T), Mean flow rate (M.F.R), Air flow rate (A.F.R) and Vocal velocity index (V.V.I) by the use of PS-77 phonatory equipment. Acoustic analysis for their voices were investigated the fundamental frequency and PPQ and APQ using the Voice Evaluation System SH-10, made by the RION Co.. In some cases, we measured the subglottic pressure to obtained the laryngeal resistance and efficiency. In this study, chronologically, subjects were classified into three age groups such 20-45, 45-65, and more than 65 years old, and each age groups divided the two groups by the values of VVI less than 50, and of more than 50.With increasing ages, they revealed a tendency of decrease of MPT values, and increase the MFR and AFR with phonatory tests, and also, decreasing of VC and FEV1 with pulmonary test. These data showed a significant difference between the young age groups and the groups more 65 years old. In acoustic analysis, fundamental frequencies in old persons showed to become more higher pitch in males, but lower in females voices. In older female subjects with VVI more than 50, weakness and lower pitch of voices were caused by reduction of subglottic pressure and glottal resistance at phonation.Results were summarized as follows : (1) Over 65 years old subjects may have a tendency to the hypotensive mode of phonation and closely be related to the reduced pulmonary power.(2) Senescent voices were become the lower pitch and weakness of voices in female, and the higher pitch in males. This might be affected with reduced subglottic pressure and pulmonary power for phonatory modality such as degenerative changes of laryngeal and pulmonary muscles.(3) Increasing values of PPQ, and APQ by aging, more detailed laryngeal senescence information may be obtained from the analysis for air flow fluctuation during phonation, and pitch perturbations and amplitude modulations for their voice.

3-12歳健常児音声の基本周波数について

Sexual difference of the fundamental frequency (F0) of the speaking voice becomes apparent after mutation of the voice. In this study,370 Chinese children (3 to 12 years of age)without any apparent secondary sex characteristics were investigated. F0 was extracted during sustained phonation of Chinese vowel /a/ and /i/ using a spectrum analyzer (B & K. Type 2031). Subjects were instructed to phonate as easy as possible. The F0 range of these subjects was from 365 Hz to 276 Hz. As age advanced, F0 became lower even before mutation. This decreasing tendency of F0 was observed especially in the boys.In the same age group, F0 of girls was higher than that of boys. This difference was statistically significant for the group of 9 to 12 years. As for vowels, F0 of /i/ was higher than that of /a/.

Vocal changes in patients undergoing radiation therapy for glottic carcinoma

A prospective evaluation of vocal changes in patients receiving radiation therapy for T1 and T2 (AJC) glottic carcinoma was undertaken in January 1987. Vocal analysis was performed prior to radiotherapy and at specific intervals throughout the radiation treatment program. The voicing ratio was extrapolated from a sustained vowel phonation using the Visipitch interfaced with the IBM-PC. Preliminary observations suggested three distinct patterns of vocal behavior: 1. reduced voicing ratio with precipitous improvement within the course of treatment, 2. high initial voicing ratio with reduction secondary to radiation induced edema, with rapid improvement in the voicing component after the edema subsided, and 3. fluctuating voicing ratio during and following treatment. Enrollment of new patients and a 2-year follow-up of current patients was undertaken.

Physiologic factors in vocal vibrato production

Four adult male singers produced sustained vowel phonation beginning with straight tone and changing to vibrato or exaggerated vibrato. The EMG signal from the cricothyroid muscle (CT) and the voice signal were recorded. Analysis showed that the muscle signal changed from a relative steady-state interference pattern during straight tone production to a modulated signal during either of the vibrato productions. Furthermore, for vocalization at the same frequency, the integrated muscle signal was approximately the same for straight tone and vibrato. Variability in the timing of CT modulation and the resultant FO oscillation was extensive, suggesting that other muscles may be involved in vibrato regulation. Four adult male singers produced sustained vowel phonation beginning with straight tone and changing to vibrato or exaggerated vibrato. The EMG signal from the cricothyroid muscle (CT) and the voice signal were recorded. Analysis showed that the muscle signal changed from a relative steady-state interference pattern during straight tone production to a modulated signal during either of the vibrato productions. Furthermore, for vocalization at the same frequency, the integrated muscle signal was approximately the same for straight tone and vibrato. Variability in the timing of CT modulation and the resultant FO oscillation was extensive, suggesting that other muscles may be involved in vibrato regulation.

Frequency modulation characteristics of sustained /a/ sung in vocal vibrato.

Frequency modulation characteristics of sustained vowel phonations in vocal vibrato were investigated. Eight male singers produced sustained /a/ in vibrato at low-, middle-, and high-pitch levels with comfortable loudness. The recorded voice samples were digitized and analyzed by a program yielding a plot of fundamental frequencies (Fo) of individual fundamental cycles. Modulation frequency, extent, rates of Fo increase and decrease, and modulation jitter and modulation shimmer were measured for individual modulation cycles. Central tendency and variability of these measures, intercorrelations among these measures, and temporal patterns of frequency modulations were investigated. Results indicated (1) significant effects of pitch levels on modulation frequency, (2) more regularity in modulation frequency than extent, (3) predominantly linear temporal patterns of frequency modulation, and (4) faster Fo increase than decrease. Implications of these findings for the nature of underlying mechanisms of frequency control in vocal vibrato are discussed.

Mean frequency of vocal vibrato relative to target frequency

<h2>Summary</h2> Six professional singers of early and contemporary music produced sustained vowel phonations at three pitch levels beginning with straight tone leading to either vibrato or to vibrato followed by exaggerated vibrato. Mean fundamental frequency (F₀) during the two vibrato conditions was compared with the target F₀, which was measured during straight tone production. During usual vibrato production the preponderance of singers lowered their mean F₀, and a lesser number maintained the straight tone mean. Only one subject elevated mean vibrato F₀. During exaggerated vibrato phonation, there were four instances of elevated F₀, but the same number of lowered F₀ as for usual vibrato.

Acoustic analyses of phonation in patients with Huntington's disease. Preliminary report.

While perceptual reports support phonatory disruptions in patients with Huntington's disease, these disruptions have not been quantified objectively. Acoustic analysis offers a method to study phonatory characteristics in these patients noninvasively and to provide objective information related to laryngeal pathophysiology of both clinical and academic interest. Application of acoustic analysis to the sustained vowel phonation of eight patients with Huntington's disease revealed the following abnormalities: low frequency segments (abrupt drops in fundamental frequency of approximately one octave), vocal arrests, and reduced maximal vowel duration. There was evidence of both adductory and abductory phonatory disruption in these patients. These findings are discussed in relation to previous reports of perceptual characteristics of voices of Huntington's disease patients, as well as potential physiologic correlates of choreiform involvement in the phonatory mechanism.

Aging speech: Physiological and sociological aspects

It is generally accepted that listeners are able to accurately classify a speech sample according to the chronological age of the speaker (Ptacek and Sander, 1966; Shipp and Hollien, 1969; Ryan and Burk, 1974; Ryan and Capadano, 1978). Impressive listener accuracy has been reported in age ratings of both connected speech (Ptacek and Sander, 1966) and sustained vowel phonation (Shipp and Hollien, 1969; Linville and Fisher, 1980). Findings such as these suggest the acoustic characteristics of speech change with advancing age (Kent and Burkard, 1981) and that listeners use certain of these acoustic characteristics in their judgments of age. For example, sustained vowel phonation of the elderly has been described perceptually as hoarse, breathy and tremorous (Ptacek and Sander, 1966; Hartman and Danhauer, 1976; Ryan and Capadano, 1978); acoustic analyses of such sustained phonation have revealed increases in fundamental frequency, jitter, shimmer and spectral noise (Wilcox and Horii, 1980; Ramig and Ringel, 1983; Ramig, 1983a). Connected speech of the elderly has been reported to be slow, have long pauses and hesitancy and be less clear (Ptacek and Sander, 1966; Hartman and Danhauer, 1976); acoustic analyses of such speech reveal increased silent time, longer pauses and increased duration of phonemes (Mysak, 1959; Hoflien and Shipp, 1972; Hartman and Danhauer, 1976; Schow ef al., 1978).

Jitter and shimmer differences among sustained vowel phonations.

This study investigated jitter and shimmer differences among eight English vowels recorded through a miniature accelerometer placed on the throat. Statistical tests indicated no significant differences in either jitter or shimmer among the eight vowels. An average jitter value of .75% and a shimmer value of .17 dB were obtained across the eight vowels and 20 subjects.

Cigarette smoking and voice fundamental frequency

The effects of long-term cigarette smoking were examined in a series of phonatory tasks. The results indicated that a significant difference existed between the fundamental frequency of the male smokers and the male nonsmokers in the oral reading and spontaneous speech tasks. Differences between the ƒ 0 values of the female smokers and nonsmokers in these tasks were not significant, but the same trends were noted. Results of the ƒ 0 analysis of the sustained vowel phonations were not significant, but showed the same trend; that is, the smokers had lower fundamental frequency values than the nonsmokers.

Effects of laryngeal topical anesthesia on voice fundamental frequency perturbation.

Fundamental frequency perturbation (jitter) during sustained vowel phonations of speakers under topical anesthesia of the larynx was investigated for five adult males. The results showed that the average jitter was significantly greater under the anesthesia than normal conditions, and that the jitter difference between the two conditions was more prominent at high frequency phonations. Implications of these data for tactile and proprioceptive feedback in phonatory frequency control are discussed.