Cepstral and Perceptual Investigations in Female Teachers With Functionally Healthy Voice

Voice disorder discrimination using vowel acoustic measures in female speakers

BACKGROUND

Sustained vowels are important vocal tasks that have been investigated in discriminating voice disorders using acoustic analysis. To date, no study has combined vowel acoustic measures only that evaluate major aspects of the pathological voice signals in voice disorder discrimination.

AIMS

To investigate the value of vowel acoustic measures that quantify glottal noise, signal stability, signal periodicity, spectral slope and overall voice quality in discriminating female speakers with and without voice disorders.

METHODS & PROCEDURES

Sustained vowel /ɑ/ samples were extracted from 133 voice-disordered female patients and 97 non-voice disordered female speakers and were signal typed prior to analysis. Praat software was used to measure harmonics-to-noise ratio (HNR), glottal-to-noise excitation ratio (GNE), the standard deviation of fundamental frequency (F0SD) and cepstral peak prominence (CPPp); and the Analysis of Dysphonia in Speech and Voice (ADSV) program was used to measure CPPadsv, low/high spectral ratio (LH) and the cepstral/spectral index of dysphonia (CSID). Outcome measures included sensitivity, specificity, and discrimination accuracy.

OUTCOMES & RESULTS

As individual acoustic measures, only spectral-based measures showed good (CPPadsv) and acceptable (CSID) discrimination results. The HNR, GNE and CPPp measures had acceptable sensitivity but poor or non-acceptable specificity and discrimination accuracy. Logistic regression models with all Praat measures (F0SD, HNR, GNE, CPPp) plus ADSV measures (CPPadsv, LH or CSID) provided excellent sensitivity, good-to-excellent specificity and excellent discrimination accuracy. ROC analysis for all individual measures showed that CPPadsv, CSID, CPPp, GNE and F0SD had the highest area under the curve (AUC) values.

CONCLUSIONS & IMPLICATIONS

A combination of acoustic measures that evaluate the major aspects of vocal dysfunction resulted in good to excellent voice discrimination outcomes. Individual acoustic measures had lower discrimination ability than combined measures. The findings implied that acoustic measures extracted from a prolonged vowel were useful in voice disorder discrimination.

WHAT THIS PAPER ADDS

What is already known on this subject Acoustic measures hold great value in discriminating voice disorders from normal voices. However, no study has evaluated discrimination values of a combination of sustained vowel acoustic measures that quantify additive noise, signal stability, signal periodicity, spectral slope and overall voice quality in single-gender cohorts. Previous studies have not used signal typing (the classification of the acoustic signals) for time-based measures, impacting the reliability of discrimination. What this study adds to the existing knowledge This study was the first to implement signal typing to include sustained vowel samples of Types 1 and 2 signals for discrimination statistics. We showed that a combination of vocal acoustic measures using time- and spectral-based extraction from the sustained /ɑ/ vowel evaluating additive noise, signal stability, signal periodicity, spectral slope and overall voice quality resulted in good to excellent sensitivity, specificity and discrimination accuracy. As individual measures, traditional time-based measures such as HNR had rather limited discrimination values whilst spectral-based measures provided higher discrimination values. Measures that are sensitive to signal types have low discrimination ability. What are the potential or actual clinical implications of this work? The sustained vowel /ɑ/ is a relevant, universal vocal task for clinical application using acoustic measures to discriminate female speakers with and without voice disorders if signal typing is implemented. Clinical voice assessment using vowels may not be effective if relying solely on time-based measurements. Spectral-based measures perform better in voice disorder discrimination given their insensitivity to signal types. The most effective voice disorder discrimination could only be obtained using a combination of acoustic measures that quantify major phenomena in the signals of disordered voices. Using measures extracted from both programs, Praat and ADSV, is useful given that specific settings in a program may impact on discrimination accuracy.

Effects of Speech Characteristics on Electroglottographic and Instrumental Acoustic Voice Analysis Metrics in Women With Structural Dysphonia Before and After Treatment

PURPOSE

Literature suggests a dependency of the acoustic metrics, smoothed cepstral peak prominence (CPPS) and harmonics-to-noise ratio (HNR), on human voice loudness and fundamental frequency (F0). Even though this has been explained with different oscillatory patterns of the vocal folds, so far, it has not been specifically investigated. In the present work, the influence of three elicitation levels, calibrated sound pressure level (SPL), F0 and vowel on the electroglottographic (EGG) and time-differentiated EGG (dEGG) metrics hybrid open quotient (OQ), dEGG OQ and peak dEGG, as well as on the acoustic metrics CPPS and HNR, was examined, and their suitability for voice assessment was evaluated.

METHOD

In a retrospective study, 29 women with a mean age of 25 years (± 8.9, range: 18-53) diagnosed with structural vocal fold pathologies were examined before and after voice therapy or phonosurgery. Both acoustic and EGG signals were recorded simultaneously during the phonation of the sustained vowels /ɑ/, /i/, and /u/ at three elicited levels of loudness (soft/comfortable/loud) and unconstrained F0 conditions.

RESULTS

A linear mixed-model analysis showed a significant effect of elicitation effort levels on peak dEGG, HNR, and CPPS (all p < .01). Calibrated SPL significantly influenced HNR and CPPS (both p < .01). Furthermore, F0 had a significant effect on peak dEGG and CPPS (p < .0001). All metrics showed significant changes with regard to vowel (all p < .05). However, the treatment had no effect on the examined metrics, regardless of the treatment type (surgery vs. voice therapy).

CONCLUSIONS

The value of the investigated metrics for voice assessment purposes when sampled without sufficient control of SPL and F0 is limited, in that they are significantly influenced by the phonatory context, be it speech or elicited sustained vowels. Future studies should explore the diagnostic value of new data collation approaches such as voice mapping, which take SPL and F0 effects into account.

Water Resistance Therapy in Individuals with Parkinson's Disease: A Session-by-Session Analysis of the Vocal Quality

OBJECTIVES

Verify session-by-session effects of the water resistance therapy (WRT) on the vocal quality of individuals with Parkinson's disease (PD).

METHODS

This is a retrospective analytical study. Then, the samples were acquired from a database composed of 10 men aged between 50 and 90 years old diagnosed with PD. The participants underwent WRT with a resonance tube; then, they were guided to perform the following phonatory tasks: comfortable pitch and loudness, high pitch, low pitch, ascending and descending glissandos, and sentence uttering. Furthermore, tube depth ranged from 2 cm to 9 cm. Finally, WRT was implemented twice per week, totaling eight sessions, each lasting 45 minutes. Participants were assessed before and after each therapy session. Hence, the data were assessed with spectrographic analysis, vocal intensity, cepstral peak prominence-smoothed, alpha ratio, L1-L0, oscillatory frequency, and auditory-perceptual assessment of overall degree, roughness, breathiness, and instability. One-way repeated measures analysis of variance and Friedman tests were applied (P < 0.05). Furthermore, Holm-Sidak and Tukey tests were used as posthoc tests.

RESULTS

After the sixth session, the spectrographic analysis revealed that the tracing color intensity of medium frequencies darkened, whereas a better result could be observed after the eighth session. Regarding vocal intensity, the improvement could be observed from the third session. Additionally, L1-L0 followed the same results. The overall degree auditory-perceptual assessment revealed the best results only after the second, third, and fourth sessions; however, after the eighth session, the instability increased.

CONCLUSIONS

WRT allowed better results from the third session, with some improvements in the sixth session. However, the instability increased after the eighth session; thus, it is important to review the phonatory tasks and session numbers to avoid an overload in the phonatory system.

A Cepstral Peak Prominence (CPP) Voice Analysis in Iranian Post-lingual Deaf Adult Cochlear Implant Users

OBJECTIVE

In standardized connected speech samples, cepstral peak prominence (CPP) and smoothed CPP (CPPS) have been described as accurate parameters to evaluate voice quality. Lack of normal auditory feedback in post-lingually deaf CI users might influence tuning the acoustic parameters in speech production. Based on shreds of evidence, normal hearing results in suitable vocal control through the sensory-motor linkage. The main aim of the present study was to compare the cepstral values between the Iranian cochlear implant group and normal peers.

METHOD

Persian CAPE-V sentences were recorded from 30 CI users and 30 healthy speakers (mean age=36.7 years, SD=13.5, range=18-60 years). Thirteen /a/vowels were extracted manually from syllables. Each subject phonated sustained /a/vowel for 5 seconds. PRAAT was used to calculate CPP and CPPS. To compare two age- and gender-matched groups, the independent sample t-test was applied. Then, ANCOVA was used to assess the impact of demographic factors on cepstral scores in CI participants.

RESULTS

Significant differences between the CI group and normal peers were discovered based on CPP and CPPS in both tasks (reading sentences and sustained vowel) (P < 0.05). Overall, CI users showed higher cepstral values. The implanted ear and prosthesis model had no significant impact on both CPP and CPPS (P ≥ 0.8).

CONCLUSION

Higher CPP and CPPS values in the CI users might be due to increased phonatory instability and spectral noise, with the possibility of decreased vocal control and its quality. The outcome suggests that CI group uses a different voice control strategy. These findings should be kept in mind for intervention methods, especially by assessing vocal characteristics and considering the voice quality in adult CI users.

Cepstral Analysis of Voice in School-Aged Children

INTRODUCTION

Dysphonia in school-aged children is attributed primarily to hyperfunctional use of voice. These can be identified through effective protocols using both acoustic and auditory-perceptual analyses.

OBJECTIVE

The current study aimed to investigate voice characteristics in school children aged 4-17 years using auditory-perceptual rating and cepstral measures of voice.

STUDY DESIGN

This is a descriptive cross-sectional observational study.

METHOD

Four hundred and fifty-seven recordings of sustained phonation of /a/ in children and adolescents obtained in a quiet room using Zoom h1 voice recorder were analyzed using auditory-perceptual evaluation by three speech-language pathologists using Grade of overall dysphonia, Roughness, Breathiness, Asthenia, and Strain(GRBAS) rating scale. The samples were classified based on age into five groups: 1) 4 to 6; 11 years 2) 7-8; 11 years, 3) 9-11; 11years 4) 12-13; 11years and 5) 14-16; 11 years. PRAAT software was used to extract Cepstral Peak Prominence (CPP) and Cepstral Peak Prominence Smoothed (CPPS). Inter-rater reliability was assessed for both auditory-perceptual and acoustic analysis.

RESULTS

Auditory-perceptual analysis revealed dysphonia in 7.8% of samples with higher rate in males than females. Inter-rater reliability for auditory-perceptual rating was found to be good (Intraclass Corelation Coefficient-0.83). Independent t test revealed statistically significant difference (P < 0.001) in both cepstral measures and mean values were lower in dysphonic than normal group. Gender effect was present for CPP in group 5(14-16;11 years) and CPPS in group 4 (12-13; 11 years). One-way analysis of variance within groups in males (P < 0.005) revealed statistical difference in both cepstral measures but not in females. Statistically significant difference was not found between ratings of both speech language pathologists for both CPP (P = 0.929) and CPPS (P = 0.965) values indicating the ratings to be reliable.

CONCLUSION

Pediatric dysphonia has received less attention when compared to adults. Assessing school-aged children for dysphonia using both auditory-perceptual and acoustic measures would aid in identifying those at risk to make appropriate referrals and plan further intervention.

Use of Auditory Feedback Amplifier in Women Without Voice Complaints: A Comparison of Acoustic Measures, Self-Rated Vocal Effort, and Voice Intensity

OBJECTIVE

To compare the immediate effects of using MindVox in women without voice complaints for 1, 3, 5, and 7 minutes of reading tasks, on acoustic measurements of the vocal signal in low, medium, and strong intensity emissions; on self-rated effort vocal, and on the intensity of voice reception and production.

METHODS

Participants read one text using MindVox for 1, 3, 5, and 7 minutes. After each time, measures of self-rated vocal effort were collected (BORG CR10-BR Scale), as well as samples of the vowel /e/ at low (>70 dB), moderate (≥70 dB and ≤80 dB), and high intensities (>80 dB). Acoustic measurements (F0, short-term acoustic measurements, and cepstral peak prominence measurements) were also collected before and after the procedure and subsequently analyzed in the CTS 5.0 Vox-Metria Program. Voice reception and production intensities were captured during the reading task using two decibel meters. One decibel meter was installed near the ear (average intensity received by the ear (EAVG)) and the other near the lips (average intensity captured near the lips (LAVG)), and the data were submitted for analysis.

RESULTS

The Cepstral Peak Prominence-Smoothed increased in the first minute, the Cepstral Peak Prominence increased in the third minute, and the jitter decreased from the first minute. All these changes were observed at low intensity and were maintained at the other time points. For every 5 dB of amplification (EAVG), there was a 1 dB decrease in voice production (LAVG).

CONCLUSION

Using MindVox in women without voice complaints brings positive immediate effects in cepstral measures and jitter at low intensity. There is a connection between the intensity of the voice received by the ear and the intensity of voice production.

Manual Therapy with Neural Mobilization: Immediate Effect on the Vocal Quality of Women with Dysphonia

OBJECTIVE

To evaluate the immediate effect of neural mobilization on the voice quality, self-perceived phonatory effort, and laryngeal muscles of women with behavioral dysphonia.

METHOD

This is an intrasubject comparative study. The research included 21 women aged 18 to 59 years with vocal complaints. Therefore, the selection of this sample excluded the lower limit of the voice change period and the upper limit of presbyphonia. The participants were assessed by voice acoustic and auditory-perceptual analysis, self-reported vocal effort, and laryngeal palpation performed at three moments: at baseline, after 10 minutes of vocal resting, and after manual therapy. The participants were divided into two groups: the group with 10 minutes of vocal resting (G1) and the group with intervention (G2). The patients in the intervention group underwent manual therapy using neural mobilization in the laryngeal region. For the statistical analysis, a descriptive analysis of the data was performed first with measures of central tendency and dispersion. Subsequently, the Anderson-Darling test was used to verify sample normality. To analyze the difference between three groups were used the parametric One-Way ANOVA or the non-parametric Friedman's test. The McNemar's or chi-squared tests were used to compare categorical variables and to compare an ordinal variable a non-parametric Wilcoxon test was used. The Gwet's AC1 test was used to assess intra-rater agreement in the auditory-perceptual analysis response.

RESULTS

Neural mobilization in the laryngeal region showed no positive effects on the acoustic voice parameters and voice quality of women with dysphonia. Phonatory effort improved after neural mobilization in the laryngeal region (p = 0.004). There was no significant change in supralaryngeal resistance, lateral laryngeal resistance, and laryngeal position after neural mobilization in the laryngeal region.

CONCLUSION

Neural mobilization improved phonatory comfort but did have any effect on the voice quality and laryngeal musculature of women with dysphonia.

Cepstral and Perceptual Investigations of Voice in Speech and Language Pathologists with Vocal Fatigue

Vocal fatigue is known as a hyperfunctional voice disorder that can lead to other conditions, such as muscle tension dysphonia (MTD). Speech and language pathologists (SLPs) are professional voice users who may suffer from vocal fatigue due to heavy vocal demands. This study aimed at investigating the cepstral and perceptual dimensions of voice and their correlation in the SLPs with vocal fatigue. Twenty-six SLPs and senior speech therapy students (mean age = 27.11 ± 6.8 yrs), including men (n = 5) and women (n = 21), participated in this descriptive cross-sectional study. They had vocal fatigue according to the Vocal Fatigue Index (VFI). In acoustic assessment, cepstral analysis (CPP and CPPS) was performed using Praat software. The Persian version of Consensus Auditory Perceptual Evaluation of Voice (CAPE-V) was used to evaluate the overall severity of dysphonia. The correlation between these two evaluations was also investigated using IBM SPSS Statistics software version 23. Results revealed that the mean CPPS (13.716 ± 2.084) was lower than the cutoff point. Perceptual findings indicated that the mean overall severity (10.557 ± 11.210) fell in the normal variability of voice quality (NVVQ) range. In addition, cepstral and perceptual evaluations had no significant correlation (P > 0/05). The findings showed that auditory-perceptual evaluation considered the gold standard method of voice evaluation, cannot solely identify vocal fatigue. However, cepstral measures can help provide a more objective profile of vocal function in SLPs with vocal fatigue. Therefore, both of these evaluations are recommended for voice assessment of vocal fatigue.

Immediate effects of the incentive spirometer in women with healthy voice

PURPOSE

To evaluate the immediate effect of the incentive spirometer on acoustic measures, aerodynamic measures and on the auditory-perceptual assessment of vocal quality in vocally healthy women.

METHODS

This is an experimental intra-subject comparison study with the participation of 22 women without vocal complaints. Acoustic measures, aerodynamic measures and auditory-perceptual assessment of vocal quality were obtained before and immediately after using the incentive spirometer by the participants. The device was used in the orthostatic position and the participants performed three sets of ten repetitions with a one-minute interval between sets.

RESULTS

After using the incentive spirometer, there was a significant reduction in jitter, shimmer and PPQ (period perturbation quotient) measurements and an increase in maximum expiratory volume, while the other acoustic and aerodynamic measurements were not significantly impacted. In addition, there was improvement in vocal quality in eight (36.4%) participants and 11 (50.0%) participants showed no changes in the auditory perceptual assessment of voice quality after using the incentive spirometer.

CONCLUSION

The use of the incentive spirometer is safe and, in its immediate effect, positively impacts the acoustic measures of short-term aperiodicity of frequency and intensity and increases the maximum expiratory volume in women with healthy voices.

Characterization of Dermatoglyphic Profiles and its Relation to Acoustic Measures in Voice Professionals

INTRODUCTION

Acoustic analysis is widely used for assessing and monitoring vocal function. Dermatoglyphics is a method that analyzes genetic fingerprint markers, and uses that information for predicting physical skills related to anaerobic (explosive strength and speed) and aerobic (motor coordination and resistance) mechanisms. Therefore, it can be used as an indicator for individualized vocal training.

OBJECTIVE

To characterize the dermatoglyphic profiles and their relation to acoustic measures in voice professionals.

METHODS

A cross-sectional study involving 79 voice professionals. Acoustic analysis was performed using the PRAAT software. Mean intensity, fundamental frequency (F0), and cepstral peak prominence (CPP) value were extracted from the sustained vowel /a/. Fingerprints were collected using a Watson mini-integrated biometric scanner, and were quantified by design predominance, delta index (D10), total ridge count (TRC), and dermatoglyphic profile. The acoustic measures were analyzed descriptively and compared, considering the subjects' dermatoglyphic profiles. The confidence levels ranged from 90% to 95%.

RESULTS

Most subjects exhibited anaerobic dermatoglyphic profiles (P = 0.004) and low TRC (p < 0.001). Higher F0 (P = 0.061), intensity (P = 0.065), and CPP (P = 0.073) were found for anaerobics (P < 0.001). There was a weak and negative correlation between TRC and intensity (P = 0.026), as well as between F0 (P = 0.017) and CPP (P = 0.069).

CONCLUSION

Anaerobic profiles were predominant. The values of F0, intensity, and CPP increased for the anaerobics. There was a weak negative correlation between the TRC and intensity, F0, and CPP measures. Dermatoglyphics could have been seen as an interesting tool in the voice assessment and training direction for voice professionals.

Analysis of different performance times of the voiced trill technique in older women

PURPOSE

To analyze and compare the immediate vocal effects of the voiced trill technique in the assessment of acoustic and auditory-perceptual measures of older women with and without self-perceived vocal changes.

METHODS

Clinical, quasi-experimental study in older women, aged 60 to 70 years (n=53). A questionnaire on vocal self-perception, voice, and laryngeal assessment was applied, before and after performing the voiced trill technique. Before and during intervals of the technique, sustained vowel samples were collected, totaling four samples. Older women were divided into two groups: one with self-perceived voice changes (n=25), and the other without self-perceived voice changes (n=28). Auditory-perceptual assessments and acoustic analysis were performed. Statistical tests were used to correlate the data: ANOVA Test for repeated measures, Friedman Test, Wilcoxon Test, and Pearson's Chi-Square Test. For all tests, the significance level was set at 5%.

RESULTS

There was a predominance of moderate dysphonia in both groups, according to the auditory-perceptual judgment. There was no statistically significant difference between the groups in the assessment of the auditory-perceptual analysis regarding voice changes (improved, worsened, and unaltered voices) before and after the different technique performance times. Most older women improved their voice after 1 minute of performing the technique.

CONCLUSION

Older women often have voice changes when considering the perceptual judgment of the voice. There was no scientific evidence as to the ideal time to obtain a better effect on older women's voices.

Relationship among five-factor personality traits and psychological distress with acoustic analysis

Objectives

The relationship between personality traits and psychological distress with acoustic characteristics was investigated in the present study, regarding the existence of dysphonia, abnormal overall voice quality (AOVQ), and dysphonia type.

Methods

Fifty-five participants with dysphonia and 64 participants without dysphonia completed NEO Five-Factor Inventory and Depression, Anxiety, and Stress Scale-21. Jitter, shimmer, noise-to-harmonic ratio (NHR), cepstral peak prominence (CPP), and cepstral peak prominence-smoothed (CPPS) were calculated in sustained vowel /a/ by Praat. Three expert speech and language pathologists divided participants with dysphonia into mild, moderate, and severe, based on the AOVQ. Pearson and Spearman correlation tests were performed by IBM SPSS Statistics.

Results

The findings were indicative of large correlations between agreeableness with CPP, conscientiousness with shimmer, depression with jitter and shimmer, and anxiety with shimmer in patients with functional dysphonia (p < 0.05). The results showed small to medium significant correlations between agreeableness with jitter and NHR, conscientiousness with CPP in participants without dysphonia, and depression with jitter in the participants with dysphonia (p < 0.05). Lastly, no significant correlation was observed between personality traits and psychological distress with acoustic characteristics in mild, moderate, and severe AOVQ groups (p > 0.05).

Conclusion

In participants with functional dysphonia, personality traits and psychological distress can provide some information about acoustic characteristics and vice versa.

Level of Evidence

3.

Auditory-perceptual Parameters as Predictors of Voice Acoustic Measures

BACKGROUND

Much research has examined the relationship between perceptual and acoustic measures. However, little is known about the prediction values of perceptual measures on an acoustic parameter.

AIMS

This study utilized simulated and disordered voice samples to investigate the prediction values of breathiness, roughness, and strain ratings on the selection of some time-based and spectral-based measures of voice quality.

METHOD

This study retrospectively analysed two sets of precollected data. The experimental data had been collected from nine trained speakers manipulating false vocal fold activity, true vocal fold mass, and larynx height. The voice-disordered data had been extracted from a clinical database for 68 patients with muscle tension voice disorders (MTVD). Both data sets had been perceptually rated for breathiness, roughness, and strain. Voice samples (prolonged vowel /ɑ/ and Rainbow Passage readings) had undergone acoustic analysis using Praat for harmonics-to-noise ratio (HNR) and the program "Analysis of Dysphonia in Speech and Voice" (ADSV) for cepstral peak prominence (CPP), Cepstral/Spectral Index of Dysphonia (CSID), and Low/High spectral ratio (L/H ratio). Perceptual parameters were regressed against these acoustic measures to test their prediction values.

RESULTS

Reliability data showed satisfactory intra- and inter-reliability of perceptual ratings for both data sets. Breathiness significantly predicted CPP (both vocal tasks) and CSID (Rainbow Passage) in experimental data and predicted all the acoustic measures in MTVD data. Roughness significantly predicted HNR, CPP, and CSID in experimental data, and CPP (Rainbow Passage) and CSID (both vocal tasks) in MTVD data. Strain (both vocal tasks) significantly predicted L/H ratio in both data sets.

CONCLUSIONS

Breathiness ratings predicted selection of HNR, CPP and CSID; roughness ratings predicted selection of CPP and CSID, and strain ratings predicted L/H ratio.

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.

Relationship Between Aerodynamic Measurement of Maximum Phonation Time With Acoustic Analysis and the Effects of Sex and Dysphonia Type

OBJECTIVES/HYPOTHESIS

This study set out to uncover the correlation between maximum phonation time (MPT) with acoustic and cepstral analysis in the dysphonic and control groups, considering the effects of sex and dysphonia type.

METHODS

For this cross-sectional study, a sample of 179 attendees (141 dysphonic and 38 control) were randomly selected and requested to sustain the vowel /a/ as long as they could with their habitual pitch and loudness. Reading standard sentences and conversational connected speech tasks were obtained too. Using Praat, the MPT, jitter, shimmer, noise-to-harmonic ratio, cepstral peak prominence (CPP), and smoothed cepstral peak prominence (CPPS) were calculated in the target vocal tasks.

RESULTS

There was a very low to low significant correlation (r = 0.00-0.50) between MPT amounts and acoustic analysis in the dysphonic group (P < 0.05), except for between MPT with shimmer (P > 0.05). In contrast, findings showed no significant correlation between MPT and acoustic analysis in the control group, not even separated by sex (P > 0.05). There was a very low to low correlation between MPT amounts and acoustic analysis in the male dysphonic group (P < 0.05), except for the MPT with shimmer (P > 0.05). There was no significant correlation between MPT and acoustic analysis in the female dysphonic group (P > 0.05), except for MPT with CPP (sustained vowel) (P < 0.05). Finally, very low to high correlations between MPT and some of the acoustic analysis in all the different dysphonia types were observed (P < 0.05).

CONCLUSIONS

MPT contains some information about the acoustic features of the dysphonic voice, specifically the CPP and smoothed cepstral peak prominence. The data suggested that the observed relationship between MPT and the acoustic analysis has the capacity to be considered for the development of new multiparametric tests of voice assessment in dysphonia, regarding the sex and dysphonia type.

Efficacy of a Semi-Occluded Vocal Tract Exercises-Therapeutic Program in Behavioral Dysphonia: A Randomized and Blinded Clinical Trial

PURPOSE

Semi-occluded vocal tract exercises (SOVTE) may improve the source and filter interaction by changing the acoustic characteristics and the impedance of the vocal tract, both in dysphonic and vocally healthy populations. However, there are a few studies that verify the effects of these exercises in a clinical trial. Thus, this study's purpose was to analyze the effectiveness of the SOVTE-Therapeutic Program (SOVTE-TP) in vocal quality and self-assessment, comparing it with Vocal Function Exercises.

METHOD

Eighteen (eight men; 10 women), ages 18-50, with behavioral dysphonia participated in this randomized and blinded clinical trial. The participants were equally randomized into two groups: Experimental Group and Vocal Function Exercises Group. They were assessed at three moments: before the treatment, after finishing it, and one month after finishing the treatment--follow up. Acoustic measures (ie, fundamental frequency, jitter, shimmer, noise-to-harmonic ratio, cepstral peak-smoothed, alpha ratio, and L1-L0), auditory-perceptual analysis, vocal fatigue index (VFI), self-perceived resonant voice, and vocal handicap index-30 (VHI-30) were measured at all assessment moments. For the two groups, the interventions happened twice per week (four weeks) and lasted 35 minutes. It was applied the repeated-measures ANOVA test (P< 0.05) and Tukey Test.

RESULTS

The acoustic measures and auditory-perceptual had no differences between the groups and moments, respectively, which means that SOVTE-TP did not cause any harm. The auditory-perceptual analysis showed a mild deviation of participants' vocal quality. All groups reduced the VFI and VHI-30 scores in M2 and kept these results at M3 also, the vocal economy sensation increased in M2, decreasing slightly in M3.

CONCLUSION

SOVTE-TP has positive effects regarding self-assessment (VFI, VHI, and resonant voice quality) on patients with mild behavioral dysphonia, and it provides the same effects as VFE.

[Evaluation of the results of treatment of patients with functional dysphonia using a cepstral test]

In order to evaluate the effectiveness of the treatment in patients with functional dysphonia, the Cepstral Peak Prominence (CPP) test was used. Twenty dysphonic women aged from 18 to 47 years were under observation. The control group consisted of 20 healthy women of close age. Patients underwent 5-7 sessions electrostimulation of laryngeal muscles and phonopedic treatment, after which a complete restoration of the voice was noted. The Praat clinical program was used, installed on a Hewlett-Packard 630 laptop (Pentium B960, 2.2 GHz). A SHURE SM94 condenser microphone was used as well. In the control group, the results were as follows: M=7.49 (SD=1.26) dB. In the main group before treatment: M=5.00 (SD=1.07) dB, after treatment: M=7.95 (SD=1.34) dB. Differences in KT values in the main group before and after treatment (5.00 dB and 7.95 dB, respectively) were significant at p<0.0001. Differences in KT values in the main group before treatment (5.00 dB) and in the control group (7.49 dB) were significant at p<0.0001. Differences in KT values in the main group after treatment (7.95 dB) and in the control group (7.49 dB) were not significant at p>0.05. The study showed high sensitivity of the method. The CPP data after treatment were higher than those before treatment and did not differ from the control ones. It is concluded that CPP is a highly sensitive method for evaluating the degree of periodicity of an acoustic signal and can be used to evaluate the effectiveness of treatment in patients with functional dysphonia.

A Cepstral Analysis of Pathological Voice Quality in the Korean Population using Praat

OBJECTIVES

This study aimed to investigate the reference values for cepstral peak prominence (CPP) and smoothed CPP (CPPS) measured using Praat in Korean speakers with the normal, healthy and pathological voice.

METHODS

A total of 4,524 Korean participants with vocally healthy (n = 410) and dysphonic voices (n = 4,114) participated in this study. The speech task consisted of a sustained vowel /a/ and a sentence reading the Korean passage "Walk". CPP and CPPS values were quickly and automatically measured in sustained vowel and continuous speech tasks using Praat script. Furthermore, three veteran speech language pathologists (SLPs) scored the severity of dysphonia using the GRBAS scale (grade, roughness, breathiness, asthenia, strain) and Consensus Auditory Perceptual Evaluation of Voice (CAPE-V).

RESULTS

Three SLPs showed high inter- and intra-rater reliabilities (IRR) in auditory-perceptual (A-P) evaluation. Significant differences were confirmed in CPP and CPPS between the normally healthy and pathological voice groups for both voice tasks (P < 0.01). The measured values of CPP and CPPS varied depending on the laryngeal pathology. In the receiver operating characteristic (ROC) curve analysis, the CPP_Vowel (CPP_V), CPPS_V, CPP_Sentence (CPP_S), and CPPS_S cut-off values were <21.5, <12.0, <19.7, and <10.1, respectively. Through ROC curve analysis, it was confirmed that CPP and CPPS had excellent diagnostic accuracy in distinguishing disordered voice (area under the ROC: 0.951-0.966).

CONCLUSION

We investigated the reference values for CPP and CPPS measured with Praat for Korean speakers and confirmed that cepstral analysis is a promising tool for differentiating pathological voice.

Bright Voice Quality and Fundamental Frequency Variation in Non-binary Speakers

OBJECTIVES

1) To investigate if vocal variation produced by assigned-female-at-birth (AFAB) non-binary people differed from vocal variation produced by cisgender (cis) participants. Cue values produced by non-binary participants were predicted to differ from those values produced by cisgender participants. 2) To determine if previous subjective assessments of bright voice quality in AFAB non-binary participants were quantifiable, and if so, if non-binary and cisgender participants differed in their voice quality production.

STUDY DESIGN

A quantitative comparative research design.

METHODS

Phonetic and statistical analyses of continuous speech samples produced by AFAB non-binary and cisgender participants. Vocal cues were mean fundamental frequency (F0) and bright voice quality, measured by cepstral peak prominence-smoothed and spectral slope, with speaker gender as the predictor.

RESULTS

At the group level, non-binary participants produced intermediate F0 values - significantly lower than the cis women's and significantly higher than the cis men's. Individually, the majority of non-binary participants produced mean F0 in this intermediate range. Non-binary participants produced significantly less negative spectral slope and higher cepstral peak prominence-smoothed, indicative of a brighter, more resonant voice quality. Individual-level results indicated that vocal training and vocal tract physiology did not fully account for the results found.

CONCLUSION

Participants' agency, particularly their motivation to alter vocal output to avoid being misgendered, has an effect on the AFAB non-binary participants' F0 production and potentially their voice quality. The majority of AFAB non-binary participants uniquely produced the cue combination of intermediate F0 and bright voice quality.

A Practical Guide to Calculating Cepstral Peak Prominence in Praat

The acoustic measure of cepstral peak prominence (CPP) is recommended for the analysis of dysphonia. Yet, clinical use of this measure is not universal, as clinicians and researchers are still learning the strengths and limitations of this measure. Furthermore, affordable access to specialized acoustic software is a significant barrier to universal CPP use. This article will provide a guide on how to calculate CPP in Praat, a free software program, using a new CPP plugin. Important external factors that could influence CPP measures are discussed, and suggestions for clinical use are provided. As CPP becomes more widely used by clinicians and researchers, it is important to consider external factors that may inadvertently influence CPP values. Controlling for these external factors will aid in reducing variability across CPP values, which will make CPP a valuable tool for both clinical and research purposes.

Effects of Resonance Tube Voice Therapy on Parkinson's Disease: Clinical Trial

PURPOSE

To verify the effect of resonance tube voice therapy on the vocal aspects of patients with Parkinson's Disease (PD).

METHOD

Intra-subject comparative controlled clinical trial with a single group assignment. Fourteen individuals with PD (10 men, mean age 66.1 years; four women, mean age 73.75 years) received eight 45-minute sessions of voice therapy, twice a week for 4 weeks. The therapy consisted of semi-occluded vocal tract exercises - phonation method in a resonance tube (glass, 27 cm x 9 mm) in water. Tube depth in water ranged from 2 cm to 9 cm, as the difficulty in carrying out the exercises increased (usual pitch, high pitch, low pitch, ascending/descending glissandos), followed by sentence production. The assessments were made three times: at baseline (Time0), after 30 days without intervention (Time1), and 1 day after eight intervention sessions (Time2). The following aspects were assessed: vocal intensity; acoustic parameters (Smoothed Cepstral Peak Prominence - CPPs, alpha ratio, and L1-L0 difference); auditory-perceptual analysis of the overall degree of vocal quality deviation; voice symptoms (Voice Symptom Scale protocol - VoiSS) and voice-related quality of life (Voice-Related Quality of Life Protocol - V-RQOL). The results were compared at the three times of assessment Time0/Time1/Time2 using one-way repeated measures ANOVA test and Tukey test (5% significance).

RESULTS

intervention significantly increased: vocal intensity, L1-L0 value of vowel /a/ and counting, CPP value in counting, and decreased: the overall degree of vocal quality deviation in 78% of participants, the total score of VoiSS protocol, the limitation, and emotional subscales. In addition, the intervention increased the score of all the domains of V-RQOL protocol - physical, socio-emotional, and total.

CONCLUSION

Resonance tube phonation in voice therapy was effective in increasing vocal intensity and long-term acoustic parameters, the improved overall degree of vocal quality, reducing voice symptoms, and increasing voice-related quality of life in individuals with PD.

The Validity of Cepstral Analysis to Distinguish Between Different Levels of Perceptual Dysphonia in the Persian Vocal Tasks

OBJECTIVES/HYPOTHESIS

The validity of cepstral analysis (Cepstral Peak Prominence [CPP] and Cepstral Peak Prominence-Smoothed [CPPS]) as an indicator of perceptual dysphonia was investigated in the Persian language STUDY DESIGN: Cross-sectional study.

METHODS

A total of 223 participants (159 with and 64 without dysphonia) uttered vowels /a/ and /i/, six standard sentences, and non-standard connected speech. All vocal samples were perceptually evaluated by three raters on a visual analog scale and put into four groups (normal voice, mild, moderate, and severe perpetual dysphonia). CPP and CPPS of sustained vowel /a/, reading the second standard sentence, and a sentence extracted from non-standard connected speech were established using "Praat" software. Statistical analysis involved a one-way factorial analysis of variance (ANOVA), Kruskal-Wallis H, Kendall's Tau-b correlation, t test, and receiver operating characteristics (ROC) curve.

RESULTS

The results showed that CPP of sustained vowels and reading the standard sentence and CPPS of sustained vowel differed significantly (P < 0.05), except between the normal voice and mild perpetual dysphonia groups (P > 0.05). The CPP of non-standard connected speech, CPPS of reading the standard sentence, and non-standard connected speech differed significantly between all groups (P < 0.05). The mean of cepstral analysis of all tasks, "averaged CPP," and "averaged CPPS" were significantly different between two groups of the normal voice and perceptual dysphonia (P < 0.05). Correlation between the cepstral analysis and the perceptual ratings demonstrated that the correlation coefficients for CPP and CPPS were between 0.4 and 0.6 (P < 0.05). ROC curve analysis revealed that the area under the ROC curve for "averaged CPP" and "averaged CPPS" was greater than 0.8 (P < 0.05). The values of 22.11 and 12.29 were determined as cut-off scores of "averaged CPP" and "averaged CPPS," respectively.

CONCLUSIONS

Cepstral analysis was known as useful clinical tool for diagnosis of perpetual dysphonia and determining its severity level in the Persian language.

Smoothed Cepstral Peak Analysis of Brazilian Children and Adolescents Speakers

INTRODUCTION

Childhood and adolescence are essential stages in the development of voice and speech quality; therefore, it is essential to understand the vocal changes that occur during this period. Frequency-based measurement methods like cepstral measurements stand out among the methods described, which are able to identify fo and estimate the periodicity and noise in the acoustic wave without establishing individual cycles of the sound wave.

METHODS

Two hundred seventy-one recordings (128 female and 131 male) from children and adolescents aged 5 to 18 years with no vocal complaints were analyzed. Three speech-language pathologists assessed the vocal quality and determined as appropriate for the age. The recordings were divided into six age groups (G1:5-7; G2:8-9; G3:10-11; G4:12; G5:13-15 and G6:16-18 years old). Sustained production of the vowel /a/ were inspected and edited using the PRAAT software. Then, it was extract de Cepstrum Peak Prominence Smoothed (CPPS) using a script in the same software. A Two-way ANOVA was applied to investigate the effect of sex, age and sex*age interaction, followed by Bonferroni's correction for each gender separately. Finally, the Student's t test for independent samples was performed to compare genders within each age group.

RESULTS

Male children and adolescents from G5 and G6 had higher CPPS measures than G1, G2 and G3 (P ≤ 0.001). In addition, G6 also had higher values than G4 (P ≤ 0.001). There was no difference between age groups in the female group. In turn, sex differences were reported from 12 years of age onwards, with higher CPPS values found for male participants compared to female participants (P ≤ 0.01).

CONCLUSION

Vocal changes that usually occur from childhood to adolescence are reflected in the acoustic CPPS measure in males, resulting in higher values in the 13 to 18 years old. On the other hand, no changes in CPPS values were observed in the age groups of female participants. Males have higher CPPS values than females and that sex differences are reported after 12 years of age.

Vocal outcomes after COVID-19 infection: acoustic voice analyses, durational measurements, self-reported findings, and auditory-perceptual evaluations

PURPOSE

The ongoing literature suggests that COVID-19 may have a potential impact on voice characteristics during the infection period. In the current study, we explored how the disease deteriorates different vocal parameters in patients who recovered from COVID-19.

METHODS

A total of 80 participants, 40 patients with a prior history of COVID-19 (20 male, 20 female) with a mean age of 39.9 ± 8.8 (range, 21-53) and 40 gender and age-matched healthy individuals (mean age, 37.3 ± 8.8; range, 21-54) were included to this study. The data of acoustic voice analyses, durational measurements, patient-reported outcomes, and auditory-perceptual evaluations were compared between the study group and the control group. Correlation analyses were conducted to examine the association between the clinical characteristics of the recovering patients and measured outcomes.

RESULTS

Maximum phonation time (MPT) and the scores of both Voice Handicap Index-10 (VHI-10) and Voice-Related Quality of Life (V-RQOL) questionnaires significantly differed between the groups, which was more evident in female participants. The overall severity score of dysphonia was found to be higher in the study group than the control group (p = 0.023), but gender-based comparisons reached significance only in males (p = 0.032). VHI-10 and V-RQOL revealed significant correlations with the symptom scores of the disease.

CONCLUSIONS

Patients with a prior history of COVID-19 had significantly lower MPT, increased VHI-10 scores, decreased voice-related quality of life based on the V-RQOL questionnaire, and higher overall severity scores in the auditory-perceptual evaluation. Self-reported voice complaints disclosed close relationships with the symptom scores of COVID-19 disease.

Active Ingredients of Voice Therapy for Muscle Tension Voice Disorders: A Retrospective Data Audit

Background: Although voice therapy is the first line treatment for muscle-tension voice disorders (MTVD), no clinical research has investigated the role of specific active ingredients. This study aimed to evaluate the efficacy of active ingredients in the treatment of MTVD. A retrospective review of a clinical voice database was conducted on 68 MTVD patients who were treated using the optimal phonation task (OPT) and sob voice quality (SVQ), as well as two different processes: task variation and negative practice (NP). Mixed-model analysis was performed on auditory–perceptual and acoustic data from voice recordings at baseline and after each technique. Active ingredients were evaluated using effect sizes. Significant overall treatment effects were observed for the treatment program. Effect sizes ranged from 0.34 (post-NP) to 0.387 (post-SVQ) for overall severity ratings. Effect sizes ranged from 0.237 (post-SVQ) to 0.445 (post-NP) for a smoothed cepstral peak prominence measure. The treatment effects did not depend upon the MTVD type (primary or secondary), treating clinicians, nor the number of sessions and days between sessions. Implementation of individual techniques that promote improved voice quality and processes that support learning resulted in improved habitual voice quality. Both voice techniques and processes can be considered as active ingredients in voice therapy.

Acoustic Variability in the Healthy Female Voice Within and Across Days: How Much and Why?

Purpose The aims of this study were (1) to quantify variability in voice production (as measured acoustically) within and across consecutive days in vocally healthy female speakers, (2) to identify which acoustic measures are sensitive to this variability, and (3) to identify participant characteristics related to such voice variability. Method Participants included 45 young women with normal voices who were stratified by age, specifically 18-23, 24-29, and 30-35 years. Following an initial acoustic and auditory-perceptual voice assessment, participants performed standardized field voice recordings 3 times daily across a 7-day period. Acoustic analyses involved 32 cepstral-, spectral-, and time-based measures of connected speech and sustained vowels. Relationships among acoustic data and select demographic, health, and lifestyle (i.e., participant-based) factors were also examined. Results Significant time-of-day effects were observed for acoustic analyses within speakers (p < .05), with voices generally being worse in the morning. No significant differences were observed across consecutive days. Variations in voice production were associated with several participant factors, including improved voice with increased voice use; self-perceived poor voice function, minimal or no alcohol consumption, and extroverted personality; and worse voice with regular or current menstruation, depression, and anxiety. Conclusions This acoustic study provides essential information regarding the nature and extent to which healthy voices vary throughout the day and week. Participant-based factors that were associated with improved voice over time included increased voice use, self-perceived poor voice function, minimal or no alcohol consumption, and extroverted personality. Factors associated with worse voice production over time included regular or current menstruation, and depression and anxiety.

Immediate effect of surface laryngeal hydration associated with tongue trill technique in amateur singers

PURPOSE

To analyze the immediate effect of laryngeal surface hydration associated with the performance of Tongue Trills (TT) on singers.

METHODS

Thirty singers without vocal complaints or laryngeal alterations divided into control (CG) and experimental (EG) groups. The CG performed the TT for five minutes. The EG was submitted a nebulization with 3 ml of saline solution followed by TT for five minutes. Voice self-assessment, acoustic analysis and perceptual assessment were performed at Pre (Pre TT) and post (PTT) moments in CG and pre (Pre TT), post hydration (PH) and post hydration + TT (PHTT) in GE. In the self-assessment were evaluated quality, stability, vocal intensity and hoarseness. There were extract the values of the Fundamental frequency; Jitter%; Shimmer%, Noise-to-harmonic Ratio e Cepstral Peak Prominence-Smoothed (CPPs) in the acoustic analyze. The perceptual evaluation was performed by an experienced speech therapist.

RESULTS

Comparing the results of self-assessment between groups showed improvement in the perception of stability and vocal intensity in the PTT (CG) in relation to PH (EG). Comparison between the EG moments showed a statistical difference in the vocal intensity perception, indicating a better results for PHTT. There was no statistical difference between the groups investigated in the perceptual assessments and acoustic analysis.

CONCLUSION

Surface laryngeal hydration does not potentiate the effect of TT on naturally hydrated singers with 3ml nebulization. For voice professionals with high vocal demand, surface hydration can be introduced during voice use to maintain vocal quality.

Effects of Vocal Intensity and Fundamental Frequency on Cepstral Peak Prominence in Patients with Voice Disorders and Vocally Healthy Controls

OBJECTIVE

Cepstrum-based voice measures, such as smoothed cepstral peak prominence (CPPS), are influenced by voice sound pressure level (SPL) in vocally healthy adults. Since it is unclear if similar effects hold in voice disordered adults and how these interact with natural fundamental frequency (fo) changes, this study examines voice SPL and fo effects on CPPS in women with vocal hyperfunction and vocally healthy controls.

STUDY DESIGN

Retrospective matched case-control study.

METHODS

Fifty-eight women with vocal hyperfunction were individually matched with 58 vocally healthy women for occupation and approximate age. The patient group comprised women exhibiting phonotraumatic vocal hyperfunction associated with vocal fold nodules (n = 39) or polyps (n = 5), and nonphonotraumatic vocal hyperfunction associated with primary muscle tension dysphonia (n = 14). All participants sustained the vowel /a/ at soft, comfortable, and loud loudness conditions. Voice SPL, fo, and CPPS (dB) were computed from acoustic voice recordings using Praat. The effects of loudness condition, measured voice SPL, and fo on CPPS were assessed with linear mixed models. Pairwise correlations among voice SPL, fo, and CPPS were assessed using multiple regression analysis.

RESULTS

Increasing voice SPL correlated significantly (P < 0.001) with higher CPPS in both patient (r2 = 0.53) and normative groups (r2 = 0.45). fo had statistically significant effects on CPPS (P < 0.001), but with a weak relation for the patient (r2 = 0.02) and control groups (r2 = 0.05).

CONCLUSIONS

In women with and without voice disorder, CPPS is highly affected by the individual's voice SPL in vowel phonation. Future studies could investigate how these effects should be controlled for to improve the diagnostic value of acoustic-based cepstral measures.

A Field-Based Approach to Establish Normative Acoustic Data for Healthy Female Voices

Purpose The primary aim of this study was to obtain high-quality acoustic normative data in natural field environments for female voices. A secondary aim was to examine acoustic measurement variability in field environments. Method This study employed a within-subject repeated-measures experimental design that included 45 young female adults with normal voices. Participants were stratified by age (18-23, 24-29, and 30-35 years). After initial evaluation and instruction, participants completed voice recordings during seven consecutive days using a standard protocol, including both connected speech and sustained vowels. Thirty-two cepstral-, spectral-, and time-based acoustic measures were acquired using Praat and the Analysis of Dysphonia in Speech and Voice. Results Among the 958 total recordings, greater than 90% satisfied inclusion criteria based on protocol compliance, peak clipping, and signal-to-noise ratio. Significant differences were observed for age (p < .05). For 19 acoustic measures, values improved significantly as signal-to-noise ratio increased. Cepstral- and spectral-based measures demonstrated less measurement variability as compared with time-based measures. Conclusions With adequate training, field audio recordings represent a viable option for clinical voice management. The significant age effects observed in this study support the need for more specific criteria when collecting and applying normative data. Cepstral- and spectral-based measures demonstrated the least measurement variability. This study provides additional evidence for multiparameter acoustic voice measurement, specifically toward ecologically valid sampling in natural environments. Future studies should expand on these findings in other populations with normal and disordered voices.

Acoustic voice characteristics with and without wearing a facemask

Facemasks are essential for healthcare workers but characteristics of the voice whilst wearing this personal protective equipment are not well understood. In the present study, we compared acoustic voice measures in recordings of sixteen adults producing standardised vocal tasks with and without wearing either a surgical mask or a KN95 mask. Data were analysed for mean spectral levels at 0-1 kHz and 1-8 kHz regions, an energy ratio between 0-1 and 1-8 kHz (LH1000), harmonics-to-noise ratio (HNR), smoothed cepstral peak prominence (CPPS), and vocal intensity. In connected speech there was significant attenuation of mean spectral level at 1-8 kHz region and there was no significant change in this measure at 0-1 kHz. Mean spectral levels of vowel did not change significantly in mask-wearing conditions. LH1000 for connected speech significantly increased whilst wearing either a surgical mask or KN95 mask but no significant change in this measure was found for vowel. HNR was higher in the mask-wearing conditions than the no-mask condition. CPPS and vocal intensity did not change in mask-wearing conditions. These findings implied an attenuation effects of wearing these types of masks on the voice spectra with surgical mask showing less impact than the KN95.

An Assessment of Different Praat Versions for Acoustic Measures Analyzed Automatically by VoiceEvalU8 and Manually by Two Raters

INTRODUCTION

The purpose of the study was to assess acoustic measures of fundamental frequency (f_o), standard deviation of f_o (SD of f_o), jitter%, shimmer%, noise-to-harmonic ratio (NHR), smoothed cepstral peak prominence (CPPS), and acoustic voice quality index analyzed through multiple Praat versions automatically by VoiceEvalU8 or manually by two raters. In addition, default settings to calculate CPPS in two Praat versions manually analyzed by two raters were compared to Maryn and Weenik²⁰ procedures for CPPS automatically analyzed by VoiceEvalU8.

METHODS

Nineteen vocally healthy females used VoiceEvalU8 to record three 5-s sustained /a/ trials, the all voiced phrase "we were away a year ago," and a 15-s speech sample twice a day for five consecutive days. Two raters manually completed acoustic analysis using different versions of Praat and compared that analysis to measures automatically generated through a version of Praat used by VoiceEvalU8. One-way analyses of variance were run for all acoustic measures with post-hoc testing by the Bonferroni method. For acoustic measures that demonstrated significant differences, intraclass correlation coefficients were conducted.

RESULTS

Results showed no significant differences across automatic and manual analysis for different versions of Praat for all acoustic measures during /a/, for f_o, jitter%, shimmer%, and NHR during the phrase, for jitter%, shimmer%, NHR, and CPPS during speech, and for acoustic voice quality index calculated from both sustained /a/ and the phrase. The default Praat settings for CPPS were not significantly different from the Maryn and Weenik²⁰ procedures for sustained /a/ and speech. Significant differences were present for SD of f_o and CPPS during the phrase and f_o and SD of f_o during speech. SD of f_o and CPPS in the phrase were moderately correlated and f_o and SD of f_o during speech demonstrated good to excellent correlations across the different versions of Praat.

CONCLUSIONS

Acoustic measures analyzed through sustained /a/ and some of the acoustic measures during the phrase and speech were not different across multiple versions of Praat. Automatic analysis by VoiceEvalU8 produced similar mean values as compared to manual analysis by two raters. Even though SD of f_o and CPPS in the phrase and f_o and SD of f_o in speech were different across the versions of Praat, the measures demonstrated moderate to excellent reliability.

Relationship of Cepstral Peak Prominence-Smoothed and Long-Term Average Spectrum with Auditory–Perceptual Analysis

Cepstral peak prominence-smoothed (CPPs) and long-term average spectrum (LTAS) are robust measures that represent the glottal source and source-filter interactions, respectively. Until now, little has been known about how physiological events impact auditory–perceptual characteristics in the objective measures of CPPs and LTAS (alpha ratio; L1–L0). Thus, this paper aims to analyze the relationship between such acoustic measures and auditory–perceptual analysis and then determine which acoustic measure best represents voice quality. We analyzed 53 voice samples of vocally healthy participants (vocally healthy group-VHG) and 49 voice samples of participants with behavioral dysphonia (dysphonic group-DG). Each voice sample was composed of sustained vowel /a/ and connected speech. CPPs seem to be the best predictor of voice deviation in both studied populations because there was moderate to strong negative correlations with general degree, breathiness, roughness, and strain (auditory–perceptual parameters). Regarding L1–L0, this measure is related to breathiness (moderate negative correlations). Hence, L1–L0 provides information about air leak through closed glottis, assisting the phonatory efficiency analysis.

The Impact of Communication Modality on Voice Production

Purpose Communicating remotely using audio and audiovisual technology is ubiquitous in modern work and social environments. Remote communication is increasing in medicine and in voice therapy delivery, and this evolution may have an impact on speakers' voices. This study sought to determine whether these communication modalities impact the voice production of typical speakers. Method The speech acoustics of 12 participants with healthy voices were recorded as they held standardized conversations with a single investigator using three communication modalities: in-person, remote-audio, and remote-audiovisual. Participants rated their vocal effort on a 100-mm visual analog scale. Results Compared to in-person communication, self-ratings of vocal effort were statistically significantly increased for remote-audiovisual communication; vocal effort during remote-audio and in-person communication were not significantly different. In comparison to in-person communication, vocal intensity and smoothed cepstral peak prominence (CPPS) were statistically significantly higher during remote-audio and remote-audiovisual communication. Effect sizes for CPPS changes were larger than for sound pressure level (SPL), and changes in CPPS and SPL between in-person and remote-audiovisual communication were not significantly correlated. Conclusions Vocal effort and SPL were increased when using remote-audio and remote-audiovisual communication in comparison to in-person communication. Voice quality was also impacted by technology use, with changes in CPPS that were consistent with, but not fully explained by, increases in SPL. This may impact the telepractice delivery of voice therapy, and further investigation is warranted.

Respiratory Muscle Strength Training to Improve Vocal Function in Patients with Presbyphonia

BACKGROUND AND OBJECTIVE

The effects of presbyphonia are compounded by the decline in respiratory function that occurs with age. Commonly recommended exercises to optimize the use of respiratory muscles during speech, such as diaphragmatic breathing, are unlikely to be intensive enough to induce respiratory changes and impact vocal function. The objective of this study was to assess the effect of adding a targeted intervention, respiratory muscle strength training, to voice exercises in a sample of patients with presbyphonia.

METHODS/DESIGN

In this prospective, randomized-controlled trial, 12 participants received either (1) vocal function exercises (VFE), (2) VFE combined with inspiratory muscle strength training (IMST), or (3) VFE combined with expiratory muscle strength training (EMST). Data collected prior to and following 4 weekly intervention sessions included respiratory measures (pulmonary function and respiratory muscle strength) and voice measures (videostroboscopy, acoustic, auditory-perceptual, aerodynamic, and self-assessment measures).

RESULTS

Participants who received IMST improved their voice quality during connected speech (smoothed cepstral peak prominence and ratings of overall voice quality) and their scores on the three self-assessment questionnaires with large to very large within-group effect sizes (|d| = 0.82-1.61). In addition, participants in the IMST group reduced their subglottal pressure with a large effect size (d = -0.92). Participants who received EMST improved their maximum expiratory strength and smoothed cepstral peak prominence with large effect sizes (d = 0.80 and 0.99, respectively) but had limited improvements in other outcomes. Participants who received only VFE decreased their amount of vocal fold bowing, improved their voice quality on a sustained vowel (amplitude perturbation quotient), and improved their Glottal Function Index score with large effect sizes (|d| = 0.74-1.00).

CONCLUSION

Preliminary data indicate that adding IMST to voice exercises may lead to the greatest benefits in patients with presbyphonia by promoting improved subglottal pressure control as well as increasing air available for phonation, resulting in improved self-assessment outcomes.

The Impact of Respiratory Function on Voice in Patients with Presbyphonia

BACKGROUND AND OBJECTIVE

Presbyphonia is an age-related voice disorder characterized by vocal fold atrophy and incomplete glottal closure during phonation. The extent to which the effects of presbyphonia may be compounded by age-related declines in the respiratory system and further impact communication and quality of life remains unknown. Therefore, the objective of this study was to determine how variations in respiratory function impacts voice measures in a sample of participants with presbyphonia.

METHODS

In this pilot study, 21 participants with presbyphonia underwent respiratory assessments (spirometry and respiratory muscle strength testing) and voice assessments (videostroboscopy, acoustic analysis, auditory-perceptual ratings, aerodynamic assessment, and self-assessments). Factor and cluster analyses were conducted to extract voice and respiratory constructs and to identify groups of participants with similar profiles. Correlations and regression analyses were conducted to better describe the relationships between voice and respiratory function.

RESULTS

Respiratory function was found to impact voice via two main pathways: through its physiological effect on voice and through its impact on general health and impairment. A lower respiratory function was associated with a lower vocal fold pliability and regularity of vibration and with an elevated aerodynamic resistance accompanied by laryngeal hyperfunction. Standardized measures of respiratory function were associated with perceived voice-related handicap. Respiratory function did not associate with voice quality, which was mostly influenced by the severity of vocal fold atrophy.

CONCLUSION

Poor respiratory health exacerbates the burden of vocal fold atrophy and, therefore, implementation of respiratory screening prior to starting voice therapy may significantly affect the treatment plan and consequently the outcomes of voice therapy in this patient population.

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.

Occupational voice is a work in progress: active risk management, habilitation and rehabilitation

The current article reviews recent literature examining occupational voice use and occupational voice disorders (January 2018–July 2019).

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.

Acoustic Breathiness Index for the Japanese-Speaking Population: Validation Study and Exploration of Affecting Factors

Objectives The purposes of this study were to validate the Acoustic Breathiness Index (ABI) for the Japanese-speaking population and to determine whether it is independent of factors such as sex, age, and perceptual ratings of roughness. Method First, the concurrent validity of the ABI for perceptual breathiness was evaluated on the concatenations of continuous speech and sustained vowels from 288 patients with varying degrees of dysphonia. The diagnostic accuracy was examined on 343 samples with 55 additional normophonic speakers. Second, the validity related to responsiveness-to-change was estimated on 222 samples obtained before and after interventions for 111 voice-disordered patients. Third, the relationships between the ABI and other variables (i.e., perceptual hoarseness/breathiness/roughness, sex, and age) were explored using bivariate and multivariate analyses for the 288 patients. Results First, the concurrent validity and the responsiveness-to-change validity were confirmed by strong correlation coefficients of .890 and .878, respectively. Second, the receiver operating characteristic analysis showed the area under the curve to be 0.939, indicating excellent accuracy. The ABI of 3.44 exhibited a sensitivity of 76.3% and a specificity of 94.1%. Third, although bivariate analyses revealed a weak relationship between ABI and roughness and an ABI difference by age, multiple regression analyses showed a strong relation between only ABI and breathiness, without a meaningful contribution from roughness, sex, and age factors. Conclusion The study confirmed that the ABI is an accurate and specific tool to estimate breathiness levels in the Japanese-speaking population and neither roughness, sex, nor age significantly affects the ABI.

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.