Acoustic correlates of dysphonia: type and severity

A Scoping Review of Artificial Intelligence Detection of Voice Pathology: Challenges and Opportunities

OBJECTIVE

Survey the current literature on artificial intelligence (AI) applications for detecting and classifying vocal pathology using voice recordings, and identify challenges and opportunities for advancing the field forward.

DATA SOURCES

PubMed, EMBASE, CINAHL, and Scopus databases.

REVIEW METHODS

A comprehensive literature search was performed following the Preferred Reporting Items for Systematic Reviews and Meta-analyses Extension for Scoping Reviews guidelines. Peer-reviewed journal articles in the English language were included if they used an AI approach to detect or classify pathological voices using voice recordings from patients diagnosed with vocal pathologies.

RESULTS

Eighty-two studies were included in the review between the years 2000 and 2023, with an increase in publication rate from one study per year in 2012 to 10 per year in 2022. Seventy-two studies (88%) were aimed at detecting the presence of voice pathology, 24 (29%) at classifying the type of voice pathology present, and 4 (5%) at assessing pathological voice using the Grade, Roughness, Breathiness, Asthenia, and Strain scale. Thirty-six databases were used to collect and analyze speech samples. Fourteen articles (17%) did not provide information about their AI model validation methodology. Zero studies moved beyond the preclinical and offline AI model development stages. Zero studies specified following a reporting guideline for AI research.

CONCLUSION

There is rising interest in the potential of AI technology to aid the detection and classification of voice pathology. Three challenges-and areas of opportunities-for advancing this research are heterogeneity of databases, lack of clinical validation studies, and inconsistent reporting.

Effect of Face Masks on Voice Quality Associated with Young and Older Chinese Adult Speakers

OBJECTIVES

Face masks have become important after the pandemic, but the change in voice when wearing a face mask is still unclear. The study investigated the effect of face masks on the acoustic and perceptual characteristics of voice quality associated with young and older Chinese adults.

METHODS

Voice samples of the sustained vowel /a/ and continuous speech produced by 44 older and 61 young adults with and without an ASTM level-3 surgical face mask were recorded and analyzed. Perceptual and acoustic parameters including mean fundamental frequency (F0) and intensity, perturbation measures (jitter and shimmer), harmonic-to-noise ratio (HNR), smoothed cepstral peak prominence (CPPs), and long-term average spectrum (LTAS) measures were obtained and compared.

RESULTS

When comparing masked to unmasked voices, for both male and female speakers, F0 and intensity showed no significant changes, except for F0 of continuous speech, which increased significantly. Meanwhile, perturbation measures such as jitter and shimmer were reduced, while HNR and CPPs increased. In addition, LTAS measures included low-frequency mean spectral energy (MSE), high-frequency MSE, and spectral tilt (ST), which were different. For perceptual measures, the overall grade of dysphonia, and roughness were reduced, except for the breathiness among older male speakers, while the other vocal qualities were not changed. Between young and older speakers, significant differences in shimmer, CPPs, and perceived breathiness among male speakers, and low-frequency MSE among female speakers were found.

CONCLUSION

Wearing a surgical mask appeared to change the perceived voice quality. This is supported by the change in perturbation and LTAS measures, and HNR and CPPs values. In addition, some differences between young and older adults were observed. Oral Communication effectiveness may be affected when wearing surgical masks due to changes in voice quality. Additionally, clinicians need to exercise hightened caution in evaluating the voice quality of clients when wearing face masks.

Experienced and Inexperienced Listeners' Perception of Vocal Strain

OBJECTIVE

The ability to perceive strain or tension in a voice is critical for both speech-language pathologists and singing teachers. Research on voice quality has focused primarily on the perception of breathiness or roughness. The perception of vocal strain has not been extensively researched and is poorly understood.

METHODS/DESIGN

This study employs a group and a within-subject design. Synthetic female sung stimuli were created that varied in source slope and vocal tract transfer function. Two groups of listeners, inexperienced listeners and experienced vocal pedagogues, listened to the stimuli and rated the perceived strain using a visual analog scale Synthetic female stimuli were constructed on the vowel /ɑ/ at 2 pitches, A3 and F5, using glottal source slopes that drop in amplitude at constant rates varying from - 6 dB/octave to - 18 dB/octave. All stimuli were filtered using three vocal tract transfer functions, one derived from a lyric/coloratura soprano, one derived from a mezzo-soprano, and a third that has resonance frequencies mid-way between the two. Listeners heard the stimuli over headphones and rated them on a scale from "no strain" to "very strained" using a visual-analog scale.

RESULTS

Spectral source slope was strongly related to the perception of strain in both groups of listeners. Experienced listeners' perception of strain was also related to formant pattern, while inexperienced listeners' perception of strain was also related to pitch.

CONCLUSION

This study has shown that spectral source slope can be a powerful cue to the perception of strain. However, inexperienced and experienced listeners also differ from each other in how strain is perceived across speaking and singing pitches. These differences may be based on both experience and the goals of the listener.

Acoustic Measures of Dysphonia in Amyotrophic Lateral Sclerosis

PURPOSE

Identifying efficacious measures to characterize dysphonia in complex neurodegenerative diseases is key to optimal assessment and intervention. This study evaluates the validity and sensitivity of acoustic features of phonatory disruption in amyotrophic lateral sclerosis (ALS).

METHOD

Forty-nine individuals with ALS (40-79 years old) were audio-recorded while producing a sustained vowel and continuous speech. Perturbation/noise-based (jitter, shimmer, and harmonics-to-noise ratio) and cepstral/spectral (cepstral peak prominence, low-high spectral ratio, and related features) acoustic measures were extracted. The criterion validity of each measure was assessed using correlations with perceptual voice ratings provided by three speech-language pathologists. Diagnostic accuracy of the acoustic features was evaluated using area-under-the-curve analysis.

RESULTS

Perturbation/noise-based and cepstral/spectral features extracted from /a/ were significantly correlated with listener ratings of roughness, breathiness, strain, and overall dysphonia. Fewer and smaller correlations between cepstral/spectral measures and perceptual ratings were observed for the continuous speech task, although post hoc analyses revealed stronger correlations in speakers with less perceptually impaired speech. Area-under-the-curve analyses revealed that multiple acoustic features, particularly from the sustained vowel task, adequately differentiated between individuals with ALS with and without perceptually dysphonic voices.

CONCLUSIONS

Our findings support using both perturbation/noise-based and cepstral/spectral measures of sustained /a/ to assess phonatory quality in ALS. Results from the continuous speech task suggest that multisubsystem involvement impacts cepstral/spectral analyses in complex motor speech disorders such as ALS. Further investigation of the validity and sensitivity of cepstral/spectral measures during continuous speech in ALS is warranted.

Is Cepstral Peak Prominence a Measure of Vocal Fatigue in Temple Priests: A Pilot Study

PURPOSE

Considering cepstral analysis of voice as a measure of overall severity of dysphonia, we tried to investigate if these measures could be considered as a metric of vocal fatigue as well. Since voice quality changes are seen as a result of vocal fatigue, we wanted to find out if there were any correlations between the cepstral measures, vocal fatigue symptoms, and auditory perceptual evaluation of voice in professional voice users.

METHOD

The pilot study was conducted on 10 temple priests belonging to the Krishna Consciousness Movement. We conducted a pre-post voice evaluation, which included recording voices before the beginning of any temple preaching in the morning and after all the preaching sessions in the evening. The priests also filled in the Vocal Fatigue Index (VFI) questionnaire twice (morning and evening), and all the voice samples were analyzed for GRBAS (Grade, Roughness, Breathiness, Asthenia, and Strain voice quality) rating by speech language pathologists with voice expertise. Correlations were obtained between the acoustic measures, VFI responses, and auditory perceptual evaluations.

RESULT

The findings of our pilot study didn't show any correlations between the cepstral measures and the questionnaire responses or with the perceptual ratings. However, the cepstral measures were slightly higher for evening recordings than the morning recordings. Our participants did not experience or perceive any voice symptoms or vocal fatigue.

CONCLUSION

Despite more than 10 hours of voice use per day for over 10 years, our participants did not experience any voice symptoms or vocal fatigue. This finding indicates that there may be diverse reasonings and opinions about the occurrence of voice problems in various professional voice users. This is particularly because the participants' responses to vocal fatigue symptoms had more of a psychological explanation (faith, self-power, etc.) rather than any physiological changes in the vocal apparatus.

Clinical Cutoff Scores for Acoustic Indices of Vocal Hyperfunction That Combine Relative Fundamental Frequency and Cepstral Peak Prominence

PURPOSE

This study examined the discriminative ability of acoustic indices of vocal hyperfunction combining smoothed cepstral peak prominence (CPPS) and relative fundamental frequency (RFF).

METHOD

Demographic, CPPS, and RFF parameters were entered into logistic regression models trained on two 1:1 case-control groups: individuals with and without nonphonotraumatic vocal hyperfunction (NPVH; n = 360) and phonotraumatic vocal hyperfunction (PVH; n = 240). Equations from the final models were used to predict group membership in two independent test sets (n = 100 each).

RESULTS

Both CPPS and RFF parameters significantly improved model fits for NPVH and PVH after accounting for demographics. CPPS explained unique variance beyond RFF in both models. RFF explained unique variance beyond CPPS in the PVH model. Final models included CPPS and RFF offset parameters for both NPVH and PVH; RFF onset parameters were significant only in the PVH model. Area under the receiver operating characteristic curve analysis for the independent test sets revealed acceptable classification for NPVH (72%) and good classification for PVH (86%).

CONCLUSIONS

A combination of CPPS and RFF parameters showed better discriminative ability than either measure alone for PVH. Clinical cutoff scores for acoustic indices of vocal hyperfunction are proposed for assessment and screening purposes.

Evaluating the Voice Type Component Distributions of Excised Larynx Phonations at Three Subglottal Pressures

Purpose The excised canine larynx provides an advantageous experimental framework in the study of voice physiology. In recent years, signal processing methods have been applied to analyze phonations in excised canine larynx experiments. However, phonations have a highly complex and nonstationary nature corresponding to different proportions of regular and chaotic signal elements. Current nonlinear dynamic methods that are used to assess the degree of irregularity in the voice fail to recognize the distribution of voice type components (VTCs). Method Based on measures of intrinsic dimension, this article presents a method to analyze the VTC distribution of phonations in excised canine larynx experiments. Thirty-nine phonation samples from 13 excised canine larynges at three different subglottal pressures were analyzed. Results Phonation produced with subglottal pressures above phonation instability pressure (PIP) and below phonation threshold pressure (PTP) resulted in high proportions of Voice Types 3 and 4, characterized by chaotic and noisy signals. Phonation produced with pressure between PTP and PIP contained mostly Type 1 voice, characterized by a regular and nearly periodic signal. Mean proportions of all VTCs varied significantly in comparisons of phonations produced with Sub-PTP and PTP as well as in comparisons of phonations produced with PTP and PIP. Conclusions Across all VTCs, the VTC profiles of normal and abnormal phonation differ significantly. Normal phonation is strongly associated with VTC₁ (Voice Type Component 1), whereas abnormal phonation exhibits increased VTC₄ (Voice Type Component 4). The study further demonstrates the ability of intrinsic dimension to successfully detect multiple voice types in an acoustic signal and highlights the need for expanded use of intrinsic dimension in human voice. Supplemental Material https://doi.org/10.23641/asha.14417585.

The Relationship Between Auditory-Perceptual Rating Scales and Objective Voice Measures in Children With Voice Disorders

Purpose The purpose of this study was to determine concurrent validity of the Grade, Roughness, Breathiness, Asthenia, and Strain (GRBAS) and Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) auditory-perceptual scales in children with voice disorders. A secondary purpose was to determine correlation between the GRBAS, CAPE-V, and objective voice measures. Method GRBAS and CAPE-V ratings and acoustic and aerodynamic measures were collected from the University of Wisconsin-Madison Voice and Swallow Outcomes Database. Correlations between CAPE-V and GRBAS ratings were calculated for overall severity of dysphonia, roughness, breathiness, and strain. Correlations between auditory-perceptual voice ratings and objective voice measures were also examined. Results One hundred thirty GRBAS and CAPE-V auditory-perceptual ratings were significantly correlated for overall severity, roughness, breathiness, and strain. r ² values were highest for overall severity of dysphonia (r ² = .75) and lowest for strain (r ² = .54). CAPE-V and GRBAS ratings were largely associated with similar acoustic and aerodynamic measures. The highest correlations were observed for auditory-perceptual ratings of breathiness and jitter% (CAPE-V r ² = .44, GRBAS r ² = .44), shimmer% (CAPE-V r ² = .45, GRBAS r ² = .45), noise-to-harmonic ratio (CAPE-V r ² = .42, GRBAS r ² = .40), fundamental frequency (CAPE-V r ² = .47, GRBAS r ² = .44), and maximum phonation time (CAPE-V r ² = .56, GRBAS r ² = .51). Akaike information criterion values indicated that CAPE-V ratings were more strongly correlated with objective voice measures than GRBAS ratings. Conclusions CAPE-V and GRBAS scales have concurrent validity in children with voice disorders. CAPE-V ratings are more strongly correlated with acoustic and aerodynamic voice measures.

The impact of Lee Silverman Voice Treatment (LSVT LOUD®) on voice, communication, and participation: Findings from a prospective, longitudinal study

BACKGROUND

Lee Silverman Voice Treatment (LSVT LOUD®), an intensive 4-week program of voice therapy, is regarded as the most well-researched, efficacious treatment for hypokinetic dysarthria in individuals with Parkinson's disease (PD). Although numerous studies have published acoustic and perceptual findings, there is comparatively little information about the impact of LSVT LOUD® on functional communication outcomes.

METHODS

This prospective, longitudinal study investigated the impact of treatment on daily communication in 25 individuals with PD. Three validated communication measures (the Voice Handicap Index, the Communicative Effectiveness Scale, and the Communicative Participation Item Bank) were given before and after treatment and again 4-8 weeks and 3-6 months following treatment. Communication partners were also asked to rate communication effectiveness at all four timepoints.

RESULTS

Significant improvements were found for all three self-reported scales which remained above baseline across all post-treatment timepoints. In addition, self-reported communicative effectiveness was significantly correlated with the assessments of communication partners. Particular benefits were reported for more complex communicative activities such as asking questions, giving detailed information, communicating in noisy situations, and speaking in groups.

CONCLUSIONS

Overall, the findings suggested that LSVT LOUD® promotes an increased sense of personal control over the communication difficulties resulting from PD by decreasing voice handicap and improving communication effectiveness and communicative participation. For individuals with PD, LSVT LOUD® may reduce the risk of social isolation by improving communication and facilitating social participation.

LEARNING OUTCOMES

As a result of this activity, the participant will be able to (1) describe the impact of PD on voice and communication, (2) discuss how these characteristics may be associated with more global measures of functional communication and particularly communicative participation, (3) explain which aspects of functional communication were affected by LSVT LOUD® as assessed by study participants and their communication partners.

Correlation Between Subjective and Objective Parameters of Voice in Elderly Male Speakers

INTRODUCTION

Literature review suggests that the analysis of acoustic, cepstral, and spectral parameters of voice offers excellent discrimination between the normal and pathological voices and strongly correlates with the perception of voice quality. Although the correlation between the subjective and objective voice measures can facilitate the clinician to distinguish pathological voices from normal voices, only a handful of investigations have examined the relationship between these measures in aging voices.

OBJECTIVES

To investigate the differences in the subjective and objective parameters (acoustic, spectral, and cepstral parameters) of the voice in elderly male speakers with and without symptoms of dysphonia, and to document the correlation between the subjective and objective parameters in the voice of elderly male speakers.

STUDY DESIGN

Retrospective standard group comparison study.

METHODS

Phonation and speech samples were collected from 30 elderly male participants having no vocal symptoms related to dysphonia and 30 elderly male participants with the self-reported presence of vocal symptoms related to dysphonia. The subjective, acoustic, spectral, and cepstral parameters were analyzed from all the voice samples.

RESULTS

Results revealed significant differences in subjective, acoustic, cepstral, and spectral parameters of voice between the voice samples of the elderly individuals with and without dysphonic symptoms. Perceptual parameters showed a weak and moderate correlation with acoustic parameters and a strong correlation with spectral and cepstral parameters of voice.

CONCLUSION

Further studies on the correlation between the subjective and objective parameters of voice in elderly male speakers with various types of laryngeal pathologies would throw light on distinguishing the voice of normal aging from the impact of any associated laryngeal pathology to make diagnostic distinctions.

Multiparameter Voice Assessment in Dysphonics: Correlation Between Objective and Perceptual Parameters

BACKGROUND

Perceptual assessment and objective measures of voice provide a quantifiable tool for determining the degree of glottal closure, thus helping to distinguish dysphonic voices from normal voices. The correlation between the perceptual and objective parameters of voice in dysphonic can enable the voice pathologist to be more effective in differentiating the normal voices from dysphonic voices. However, only a few studies have investigated the correlation between these measures.

OBJECTIVE

To document the differences in the perceptual and objective parameters of voice in participants with dysphonia and normal controls and to investigate the correlation between the perceptual and objective parameters of voice among participants with dysphonia.

STUDY DESIGN

This investigation deployed standard group comparison and a retrospective study.

METHODS

Two groups of participants were included in the study. Participants in group 1 were diagnosed as having a voice disorder secondary to organic pathologies and group 2 participants had a clinically normal voice. Phonation samples of all the participants were collected and perceptual analysis was carried out using the GRBAS rating scale. As part of the objective measures, acoustic and cepstral measures were extracted from the phonation samples.

RESULTS

The analysis of the results revealed significant differences in perceptual ratings between the normal (control) and dysphonic groups. The mean values of all the objective measures of voice presented significant differences between participants of both groups. The perceptual ratings of grade, breathiness, and roughness showed better correlations with the cepstral measures than with the time-based acoustic measures.

CONCLUSIONS

Further foraging research on the correlation between perceptual and objective measures of voice in various degrees of dysphonia will improve reliability while discriminating and quantifying hoarse, harsh and breathy voices from modal voices.

Effects of Fundamental Frequency, Vocal Intensity, Sample Duration, and Vowel Context in Cepstral and Spectral Measures of Dysphonic Voices

Purpose Smoothed cepstral peak prominence (CPPS) and harmonics-to-noise ratio (HNR) are acoustic measures related to the periodicity, harmonicity, and noise components of an acoustic signal. To date, there is little evidence about the advantages of CPPS over HNR in voice diagnostics. Recent studies indicate that voice fundamental frequency (F0) and intensity (sound pressure level [SPL]), sample duration (DUR), vowel context (speech vs. sustained phonation), and syllable stress (SS) may influence CPPS and HNR results. The scope of this work was to investigate the effects of voice F0 and SPL, DUR, SS, and token on CPPS and HNR in dysphonic voices. Method In this retrospective study, 27 Brazilian Portuguese speakers with voice disorders were investigated. Recordings of sustained vowels (SVs) /a:/ and manually extracted vowels (EVs) /a/ from Consensus Auditory-Perceptual Evaluation of Voice sentences were acoustically analyzed with the Praat program. Results There was a highly significant effect of F0, SPL, and DUR on both CPPS and HNR (p < .001), whereas SS and vowel context significantly affected CPPS only (p < .05). Higher SPL, F0, and lower DUR were related to higher CPPS and HNR. SVs moderately-to-highly correlated with EVs for CPPS, whereas HNR had few and moderate correlations. In addition, CPPS and HNR highly correlated in SVs and seven EVs (p < .05). Conclusion Speaking prosodic variations of F0, SPL, and DUR influenced both CPPS and HNR measures and led to acoustic differences between sustained and excised vowels, especially in CPPS. Vowel context, prosodic factors, and token type should be controlled for in clinical acoustic voice assessment.

How Does Our Voice Change as We Age? A Systematic Review and Meta-Analysis of Acoustic and Perceptual Voice Data From Healthy Adults Over 50 Years of Age

Purpose Approximately 30% of adults over the age of 50 years present with altered vocal function. Our understanding of how these changes manifest acoustically and perceptually is derived from relatively modest-sized studies using a diversity of tools. Voice changes can arise from the onset of disease or disorder, but also age-related physiological changes, which may not reflect pathology as such. Here, we bring together data on acoustic, perceptual, and instrumental assessments (electroglottography), with the aim of gaining a better understanding of the changes occurring across these measurement domains. We consider these changes in the context of different acoustic features, software programs, and perceptual protocols. Method Studies of voice function in healthy older adults over the age of 50 years were sought. Literature was systematically searched with 746 abstracts reviewed. Forty-seven studies were included in the review. A meta-analysis of included studies compared voice acoustic parameters between sex and age. Sixteen acoustic parameters collected from 1,475 participants were analyzed in the meta-analysis. These included some previously unpublished analyses using data provided by authors of included studies. Results Data from the systematic review suggest that older individuals are perceived to present with higher overall scores of dysphonia and roughness, breathiness, strain, and instability. Acoustically, males have significantly higher scores on measures of perturbation, including noise-to-harmonic ratio and absolute jitter. The meta-analysis outcomes suggest that participants aged 80-89 years produce significantly higher fundamental frequency, jitter percent, shimmer percent, and shimmer in decibels compared to participants aged 60-69 years and a significant increase in relative average perturbation, jitter percent, and shimmer in decibels compared to participants aged 70-79 years. Limited data were available comparing acoustic measures using the same acoustic software. Conclusions Variations in fundamental frequency and frequency and amplitude perturbation increase as healthy adults age. It was difficult to draw definitive conclusions based on existing literature due to variability in hardware used, limited descriptions of study cohorts, or missing data from statistical analysis. Supplemental Material https://doi.org/10.23641/asha.11868663.

Fundamental Frequency and Intensity Effects on Cepstral Measures in Vowels from Connected Speech of Speakers with Voice Disorders

OBJECTIVE

Cepstral peak prominence (CPP) and smoothed CPP (CPPS) have been described as reliable parameters to detect overall dysphonia in standardized connected speech samples. Recent studies indicate that vocal intensity (sound pressure level, SPL) and fundamental frequency (f_o) changes may influence cepstral measurement results in healthy speakers. The main aim of the present work was to investigate the effects of prosody related SPL and f_o variations on cepstral measures in speech of adults with voice disorders.

STUDY DESIGN

Retrospective cross-sectional study.

METHODS

Recordings of CAPE-V sentences from 27 voice disordered Brazilian Portuguese speakers (19 women, eight men) with a mean age of 45 years (SD = 13) were investigated. Five /a/ vowels were manually extracted from stressed syllables in different positions. Voice f_o (Hz), SPL (dBA), CPP (dB), and CPPS (dB) were computed using PRAAT. Statistical analysis included Linear Mixed Models with ANCOVA and Bonferroni post hoc tests.

RESULTS

Voice SPL as single factor and combined with f_o had a highly significant effect (P ≤ 0.001), while f_o alone had no significant impact on both CPP and CPPS (P ≥ 0.77). Voice f_o, SPL, CPP, and CPPS of the first vowel were all significantly lower than of the last vowel (P ≤ 0.03).

CONCLUSION

In vowel samples from connected speech of adults with voice disorders, we observed better CPP and CPPS in higher voice SPL alone and combined with higher f_o. Further, the vowel position influenced the present results. A larger clinical study should confirm how prosody related SPL and f_o and vowel position effects could be controlled for in connected speech samples.

A Case of Specificity: How Does the Acoustic Voice Quality Index Perform in Normophonic Subjects?

The acoustic voice quality index (AVQI) is a multiparametric tool based on six acoustic measurements to quantify overall voice quality in an objective manner, with the smoothed version of the cepstral peak prominence (CPPS) as its main contributor. In the last decade, many studies demonstrated its robust diagnostic accuracy and high sensitivity to voice changes across voice therapy in different languages. The aim of the present study was to provide information regarding AVQI’s and CPPS’s performance in normophonic non-treatment-seeking subjects, since these data are still scarce; concatenated voice samples, consisting of sustained vowel phonation and continuous speech, from 123 subjects (72 females, 51 males; between 20 and 60 years old) without vocally relevant complaints were evaluated by three raters and run in AVQI v.02.06. According to this auditory-perceptual evaluation, two cohorts were set up (normophonia versus slight perceived dysphonia). First, gender effects were investigated. Secondly, between-cohort differences in AVQI and CPPS were investigated. Thirdly, with the number of judges giving G = 1 to partition three sub-levels of slight hoarseness as an independent factor, differences in AVQI and CPPS across these sub-levels were investigated; for AVQI, no significant gender effect was found, whereas, for CPPS, significant trends were observed. For both AVQI and CPPS, no significant differences were found between normophonic and slightly dysphonic subjects. For AVQI, however, this difference did approach significance; these findings emphasize the need for a normative study with a greater sample size and subsequently greater statistical power to detect possible significant effects and differences.

Cell Yell!: Health Risks in Telehealth

Purpose

The purpose of this study was to determine if the use of visual feedback can overcome the absence of side tone to control for vocal quality changes, specifically loudness, with speakerphone use.

Method

Ten men and 10 women held two 5-min conversations in pairs under audio-only and audiovisual communication conditions. Acoustical data and a number of conversational collisions (communication partners trying to speak at the same time) under each condition were compared.

Results

There were no statistically significant differences in acoustical measures of voice quality between audio-only and audiovisual conversations; however, vocal intensity was consistently 4 times more powerful than average face-to-face conversational intensity during both conditions. The number of conversational collisions was significantly less for the audiovisual condition as compared to the audio-only condition.

Conclusion

Results suggest that visual feedback did allow for modulation of conversational flow (fewer conversational collisions) but did not allow for modulation of vocal quality. Visual feedback did not overcome the absence of side tone and resulted in the same increased conversational loudness observed during the audio-only condition. As a result, remote conversational partners such as clients and telehealth practitioners are more susceptible to developing vocal health issues.

The Effects of Size and Type of Vocal Fold Polyp on Some Acoustic Voice Parameters

BACKGROUND

Vocal abuse and misuse would result in vocal fold polyp. Certain features define the extent of vocal folds polyp effects on voice acoustic parameters. The present study aimed to define the effects of polyp size on acoustic voice parameters, and compare these parameters in hemorrhagic and non-hemorrhagic polyps.

METHODS

In the present retrospective study, 28 individuals with hemorrhagic or non-hemorrhagic polyps of the true vocal folds were recruited to investigate acoustic voice parameters of vowel/ æ/ computed by the Praat software. The data were analyzed using the SPSS software, version 17.0. According to the type and size of polyps, mean acoustic differences and correlations were analyzed by the statistical t test and Pearson correlation test, respectively; with significance level below 0.05.

RESULTS

The results indicated that jitter and the harmonics-to-noise ratio had a significant positive and negative correlation with the polyp size (P=0.01), respectively. In addition, both mentioned parameters were significantly different between the two types of the investigated polyps.

CONCLUSION

Both the type and size of polyps have effects on acoustic voice characteristics. In the present study, a novel method to measure polyp size was introduced. Further confirmation of this method as a tool to compare polyp sizes requires additional investigations.

A Meta-Analysis: Acoustic Measurement of Roughness and Breathiness

PURPOSE

Over the last 5 decades, many acoustic measures have been created to measure roughness and breathiness. The aim of this study is to present a meta-analysis of correlation coefficients (r) between auditory-perceptual judgment of roughness and breathiness and various acoustic measures in both sustained vowels and continuous speech.

METHOD

Scientific literature reporting perceptual-acoustic correlations on roughness and breathiness were sought in 28 databases. Weighted average correlation coefficients (rw) were calculated when multiple r-values were available for a specific acoustic marker. An rw ≥ .60 was the threshold for an acoustic measure to be considered acceptable.

RESULTS

From 103 studies of roughness and 107 studies of breathiness that were investigated, only 33 studies and 34 studies, respectively, met the inclusion criteria of the meta-analysis on sustained vowels. Eighty-six acoustic measures were identified for roughness and 85 acoustic measures for breathiness on sustained vowels, in which 43 and 39 measures, respectively, yielded multiple r-values. Finally, only 14 measures for roughness and 12 measures for breathiness produced rw ≥ .60. On continuous speech, 4 measures for roughness and 21 measures for breathiness were identified, yielding 3 and 6 measures, respectively, with multiple r-values in which only 1 and 2, respectively, had rw ≥ .60.

CONCLUSION

This meta-analysis showed that only a few acoustic parameters were determined as the best estimators for roughness and breathiness.

How Do Voice Perceptual Changes Predict Acoustic Parameters in Persian Voice Patients?

INTRODUCTION

Perceptual and acoustic analyses are essential tools that help voice therapists comprehensively assess voice quality. While perceptual evaluations are subjective and are influenced by external and culturally driven factors, acoustic analysis is an objective and reliable means of evaluating voice. The goals of this study were (1) to determine which acoustic parameters were predicted by perceptual voice quality and (2) to assess the effect of a short period of training on the reliability of perceptual voice analyses for Persian speakers.

METHOD

This was a cross-sectional study. Subjects were 20 patients with various voice disorders. Voice samples were obtained during text reading and /a/ prolongation. Fifteen expert voice clinicians completed perceptual evaluations on voice samples using the Grade, Roughness, Breathiness, Asthenia, and Strain scale. We repeated this process after a short period of perceptual voice evaluation training. Acoustic analysis was completed using the Praat program. We used the intraclass correlation coefficient (ICC) for reliability measurement of the perceptual evaluation results and ordinal regression procedures to analyze all data. Significance level was set at P < 0.05.

RESULTS

Both intrarater and interrater reliability increased after training, for all five parameters. The ICC for grade increased to 0.95 after training. Grade and roughness significantly predicted fundamental frequency (F0) (P = 0.021 and P = 0.030, respectively) and harmonic-to-noise ratio (HNR) (P = 0.019 and P = 0.016, respectively). Breathiness significantly predicted shimmer (P = 0.013).

CONCLUSION

Training had a positive effect and increased the reliability of perceptual voice evaluation. For Persian listeners, changes in F0, increases in HNR, and shimmer were perceptually associated with poor voice quality.

Pitch Deviation Analysis of Pathological Voice in Connected Speech

Objectives

This study compares normal and pathologic voices using a novel voice analysis algorithm that examines pitch deviation during connected speech. The study evaluates the clinical potential of the algorithm as a mechanism to distinguish between normal and pathologic voices using connected speech.

Methods

Adult vocalizations from normal subjects and patients with known benign free-edge vocal fold lesions were analyzed. Recordings had been previously obtained in quiet under controlled conditions. Two phrases and sustained /a/ were recorded per subject. The subject populations consisted of 10 normal and 31 abnormal subjects. The voice analysis algorithm generated 2-dimensional patterns that represent pitch deviation in time and under variable window widths. Measures were collected from these patterns for window widths between 10 and 250 ms. For comparison, jitter and shimmer measures were collected from sustained /a/ by means of the Computerized Speech Lab (CSL). A t-test and tests of sensitivity and specificity assessed discrimination between normal and abnormal populations.

Results

More than 58% of the measures collected from connected speech outperformed the CSL jitter and shimmer measures in population discrimination. Twenty-five percent of the experimental measures (including /a/) indicated significantly different populations (p < .01%).

Conclusions

The results demonstrate that the algorithm distinguishes between normal and abnormal populations by use of samples of connected speech.

Objective Voice Analysis of Pediatric Cochlear Implant Recipients and Comparison With Hearing Aids Users and Hearing Controls

OBJECTIVES

Phonation is influenced by hearing as a feedback mechanism. The purpose of the present study was to compare selected acoustic parameters in children using cochlear implants (CIs), those using hearing aids (HA), and their normal-hearing (NH) peers.

METHODS

The participants were 15 children using CI (mean age: 72 months), 15 children using HA (mean age: 74 months), and 15 NH children (mean age: 77 months). The vowel /a/ was produced to measure perturbation and mean fundamental frequency. The six Persian vowels in /C_bVC_d/ were obtained to extract vowel duration. Data were analyzed by one-way analysis of variance.

RESULTS

Results revealed a statistically significant difference between the NH group and the HA group regarding fundamental frequency (F_2,51 = 3.443, P < 0.05), jitter local (F_2,51 = 1.629, P < 0.05), jitter local absolute (F_2,51 = 6.519, P < 0.001), jitter rap (F_2,51 = 7.151, P < 0.001), jitter ppq5 (F_2,51 = 5.894, P < 0.001), shimmer local (%) (F_2,51 = 8.070, P < 0.001), shimmer local (dB) (F_2,51 = 3.884, P < 0.05), shimmer apq3 (F_2,51 = 4.926, P < 0.05), shimmer apq5 (F_2,51 = 8.442, P < 0.001), and harmonic-to-noise ratio (F_2,51 = 4.117, P < 0.001). The mean values of the duration of all six vowels were significantly greater in children with CI and HA than in NH children (P < 0.001).

CONCLUSION

It seems that after 8 months of using CI, auditory control of voice production would be enabled. Furthermore, children with hearing impairment potentially regard vowel sound duration as a distinguishing feature, whereas in NH speakers, the duration has the least effect in vowel identification.

Cepstral Analysis of Voice in Patients With Thyroidectomy

Objectives

The vocal changes after a thyroidectomy are temporary and nonsevere, therefore, obtaining accurate analytical results on the pathological vocal characteristics following such a procedure is difficult. For a more objective acoustic analysis, this study used the cepstral analysis method to examine changes in the patients’ voices during the perioperative period regarding sustained vowel phonation.

Methods

The sustained phonation of the five vowels (i.e., /a/, /e/, /i/, /o/, and /u/) by 35 patients with thyroidectomy were recorded by using a Multi-Speech program. Of the 35 patients, 10 were men and 25 were women, with an average age of 51.5 years. Voice data were collected a total of 3 times (preoperatively, 5–7 days after the operation, and 6 weeks after the operation) and were edited according to each fragment (on-set, mid, and off-set) for cepstral analysis.

Results

The cepstral analysis on the patients’ voices revealed no significant differences between the examination periods of all vowel phonations. However, analysis of the on-set fragment of the vowel /i/ revealed pathological characteristics in which the cepstral measurements of the voice were significantly lower after the operation than before the operation, with the cepstral measurements of the voice increasing further 6 weeks following surgery.

Conclusion

The results of the acoustic analysis on the on-set fragment of the vowel /i/ will be important data for characterizing the vocal changes during the perioperative period. This study contributes to future research on the mechanisms underlying changes in the voice of patients with a history of thyroid or neck surgery.

Effects of age on the amplitude, frequency and perceived quality of voice

The manner and extent to which voice amplitude and frequency control mechanisms change with age is not well understood. The related question of whether the assessment of one's own voice evolves with age, concomitant with the acoustical changes that the voice undergoes, also remains unanswered. In the present study, we characterized the aging of voice production mechanisms (amplitude, frequency), compared the aging voice in different experimental contexts (vowel utterance, connected speech) and examined the relationship between voice self-assessment and age-related voice acoustical changes. Eighty healthy adults (20 to 75 years old) participated in the study, which involved computation of several acoustical measures of voice (including measures of fundamental frequency, voice amplitude, and stability) as well as self-assessments of voice. Because depression is frequent in older adults, depression and anxiety scores were also measured. As was expected, analyses revealed age effects on most acoustical measures. However, there was no interaction between age and the ability to produce high/low voice amplitude/frequency, suggesting that voice amplitude and frequency control mechanisms are preserved in aging. Multiple mediation analyses demonstrated that the relationship between age and voice self-assessment was moderated by depression and anxiety scores. Taken together, these results reveal that while voice production undergoes important changes throughout aging, the ability to increase/decrease the amplitude and frequency of voice are preserved, at least within the age range studied, and that depression and anxiety scores have a stronger impact on perceived voice quality than acoustical changes themselves.

Integrating voice evaluation: correlation between acoustic and audio-perceptual measures

OBJECTIVES/HYPOTHESIS

This article aims to establish correlations between acoustic and audio-perceptual measures using the GRBAS scale with respect to four different voice analysis software programs.

STUDY DESIGN

Exploratory, transversal.

METHODS

A total of 90 voice records were collected and analyzed with the Dr. Speech (Tiger Electronics, Seattle, WA), Multidimensional Voice Program (Kay Elemetrics, NJ, USA), PRAAT (University of Amsterdam, The Netherlands), and Voice Studio (Seegnal, Oporto, Portugal) software programs. The acoustic measures were correlated to the audio-perceptual parameters of the GRBAS and rated by 10 experts.

RESULTS

The predictive value of the acoustic measurements related to the audio-perceptual parameters exhibited magnitudes ranging from weak (R(2)a=0.17) to moderate (R(2)a=0.71). The parameter exhibiting the highest correlation magnitude is B (Breathiness), whereas the weaker correlation magnitudes were found to be for A (Asthenia) and S (Strain). The acoustic measures with stronger predictive values were local Shimmer, harmonics-to-noise ratio, APQ5 shimmer, and PPQ5 jitter, with different magnitudes for each one of the studied software programs.

CONCLUSIONS

Some acoustic measures are pointed as significant predictors of GRBAS parameters, but they differ among software programs. B (Breathiness) was the parameter exhibiting the highest correlation magnitude.

The effect of experience on perceptual spaces when judging synthesized voice quality: a multidimensional scaling study

OBJECTIVES/HYPOTHESIS

The purpose of this study was to determine the effect of experience on the perceptual space of listeners when judging voice quality.

STUDY DESIGN

This was a within-subjects group design.

METHOD

Speech-language pathologists, singing voice teachers, speech-language pathology graduate students with and without experience with a voice client, graduate students who have completed a voice pedagogy course, and inexperienced served as listeners. Each participant rated the similarity of pairs of synthesized stimuli with systematically altered measurements of jitter, shimmer, and noise-to-harmonics ratio on a visual analog scale ranging from no similarity to extremely similar.

RESULTS

Results showed that participants with different levels and types of experience used different perceptual spaces (of additive noise and perturbation measures) when judging the similarity of stimulus pairs.

CONCLUSION

The conclusion was that perceptual spaces differ among individuals with different levels and types of experience when judging the similarity of pairs of stimuli with systematically altered acoustical measurements.

Spectral-Cepstral Estimation of Dysphonia Severity: External Validation

Objectives:

The current study applied an acoustic algorithm incorporating measures from cepstral and spectral analyses, the Cepstral Spectral Index of Dysphonia (CSID), in an attempt to externally validate the CSID as an acoustic estimate of dysphonia severity.

Methods:

Correlation (Pearson's r) between the CSID and trained listener-perceived severities as rated on the Consensus Auditory-Perceptual Evaluation of Voice (CAPE-V) was calculated from sentence and sustained vowel samples from 56 patients before or after they underwent thyroid surgery.

Results:

A strong correlation was identified between the mean CSID values calculated across CAPE-V sentences and vowels and the median rating of perceived overall severity ( r = 0.82; p < 0.001). The CSID values did not differ significantly from their corresponding auditory-perceptual ratings of dysphonia severity for these samples (CSID: Mean, 15.54, SD, 16.63; CAPE-V Severity: Mean, 17.33, SD, 13.61; p = 0.16).

Conclusions:

Independent testing of an acoustic algorithm incorporating measures from cepstral and spectral analyses (the CSID) confirmed a strong correlation of the CSID to perceptual ratings of overall voice quality. This study provides external validation of the CSID as a robust correlate of dysphonia severity as rated by trained listeners.

Effects of omeprazole over voice quality in muscle tension dysphonia patients with laryngopharyngeal reflux

Backround

Laryngopharyngeal reflux (LPR) is the backflow of stomach contents above upper esophageal sphincter, into the pharynx, larynx, and upper aerodigestive system.

Objectives

In this study, effects of omeprazole over voice quality in muscle tension dysphonia with laryngopharyngeal reflux was ınvestigated.

Patients and Methods

Nine patients, 7 males and 2 females, aged between 27-43 (mean age:31) were included to this study. The diagnosis of muscle tension dysphonia with LPR was established by video laryngoscopy, rigid scope 70º. The laryngeal changes related with LPR were evaluated according to Reflux Finding Score. The patients received omeprazole 20 mg twice a day for a period of 6 months. None of the patients received voice therapy. Vocal hygiene guidelines were also explained to the patients. Objective and subjective voice parameters (Jitter, shimmer, NHR, Voice Handicap Index, and Auditive analysis; Roughness, breathiness, and hoarseness) were evaluated in this study.

Results

After treatment with omeprazol, all the parameters showed an improvement in voice quality, but only VHI (P = 0) and shimmer (P = 0,018) are statistically significant.

Conclusions

For FD patients with LPR condition, we highly recommend that LPR treatment should be part of the treatment plan.

Nonlinear dynamic-based analysis of severe dysphonia in patients with vocal fold scar and sulcus vocalis

OBJECTIVE

The primary goal of this study was to evaluate a nonlinear dynamic approach to the acoustic analysis of dysphonia associated with vocal fold scar and sulcus vocalis.

STUDY DESIGN

Case-control study.

METHODS

Acoustic voice samples from scar/sulcus patients and age-/sex-matched controls were analyzed using correlation dimension (D2) and phase plots, time-domain based perturbation indices (jitter, shimmer, signal-to-noise ratio [SNR]), and an auditory-perceptual rating scheme. Signal typing was performed to identify samples with bifurcations and aperiodicity.

RESULTS

Type 2 and 3 acoustic signals were highly represented in the scar/sulcus patient group. When data were analyzed irrespective of signal type, all perceptual and acoustic indices successfully distinguished scar/sulcus patients from controls. Removal of type 2 and 3 signals eliminated the previously identified differences between experimental groups for all acoustic indices except D2. The strongest perceptual-acoustic correlation in our data set was observed for SNR and the weakest correlation was observed for D2.

CONCLUSIONS

These findings suggest that D2 is inferior to time-domain based perturbation measures for the analysis of dysphonia associated with scar/sulcus; however, time-domain based algorithms are inherently susceptible to inflation under highly aperiodic (ie, type 2 and 3) signal conditions. Auditory-perceptual analysis, unhindered by signal aperiodicity, is therefore a robust strategy for distinguishing scar/sulcus patient voices from normal voices. Future acoustic analysis research in this area should consider alternative (e.g., frequency- and quefrency-domain based) measures alongside additional nonlinear approaches.