Measures Of Voice Quality Research Articles

Clinical Effects of Voice Therapy on Vocal Outcomes in Unilateral Vocal Fold Paralysis: Proof-of-Concept Study for Two SOVT-Based Treatment Protocols

BackgroundStudies on treatment efficacy in unilateral vocal fold paralysis (UVFP) often lack a predetermined treatment protocol, and little is known about the effects of specific vocal techniques on vocal outcomes and quality of life in UVFP patients. The purpose of this preliminary proof of concept study is to investigate the effects and feasibility of two intensive treatment protocols based on water-resistance therapy (WRT) and vocal function exercises (VFE). MethodsTen participants with acute or chronic UVFP/paresis were recruited in the study and randomly assigned to the WRT or VFE group. Three of these participants presented with aphonia and could not complete the program as prescribed. The remaining participants completed an intensive therapy program with the assigned vocal technique. Before, during, and after the program, a multidimensional voice assessment was performed. Maximum phonation time, acoustic, perceptual, and patient-reported outcome measures were obtained. ResultsWRT and VFE had positive clinical effects on instrumental and auditory-perceptual voice quality, glottal closure, and patient-reported outcome measures, but inter-individual variability was high. Studies with larger sample sizes are necessary to confirm or refute these findings. ConclusionThe WRT- and VFE-based therapy programs are both feasible and seem to elicit positive clinical changes in UVFP patients. Suggestions on how to improve the programs are provided, as well as considerations for implementation in clinical practice. Follow-up research is needed to examine the efficacy of both programs on group level.

An Exploration of Voice Quality in Mothers Speaking Canadian English to Infants

ABSTRACT Research on the acoustic characteristics of Infant Directed Speech (IDS) in North American English indicates that it is generally higher-pitched than Adult Directed Speech (ADS) and has unique prosodic characteristics, which is commonly found across many spoken languages. However, very little research has addressed another important aspect of prosody: voice quality. In the current study, 25 English-speaking mothers from Canada were recorded speaking to their infant children and to an adult peer. Five acoustic measures of voice quality, including glottal constriction, spectral tilt, Harmonic-to-Noise Ratio (HNR), and Cepstral Peak Prominence (CPP), were analyzed. Only CPP, a measure of the breathiness of a speaker’s voice, and corrected H1-A2, a measure of vocal creakiness, were found to be significantly different between the IDS and ADS registers. Sociolinguistic research identifies voice quality as a key indicator of speech style and persona; we connect the pattern of breathiness in IDS to a possible “parental persona” that builds on the affective intent of IDS (rather than the pedagogical intent), with suggestions for future research.

Voice analysis for intoxication detection in laboratory versus law enforcement contexts

There is substantial interest in deploying voice biomarkers for the detection of alcohol intoxication, yet it remains unknown how other mental and physical states (e.g. emotion, stress) influence voice biomarkers in intoxicated speech. We compared measurements of voice quality (jitter, shimmer, noise-harmonics ratio) across two datasets of alcohol-intoxicated speech: (1) The alcohol language corpus, which contains laboratory elicited speech from 167 individuals in both sober and intoxicated conditions and (2) a custom dataset of police (control, n = 14) and suspect (intoxicated, n = 32) interactions during traffic stops where intoxication was verified via breath analysis. Measurements were extracted from all stressed vowel tokens and compared across conditions using two-sample t-tests within sex-specific groupings of each dataset. For both males and females, jitter was significantly lower during intoxication as measured from laboratory-elicited speech, but significantly higher for intoxicated individuals when measured from police–suspect interactions. These results suggest that voice biomarkers for alcohol-intoxication are easily confounded by other emotional and physical states (e.g., stress during police interaction), and thus, present a particular challenge for speaker-independent detection systems where baseline voice quality measurements across different emotional states are unknown. [Research funded by Tenvos Incorporated for the development of commercial speaker state-detection algorithms.]

Smartphone-Based Voice Wellness Index Application for Dysphonia Screening and Assessment: Development and Reliability.

This study aimed to develop a Voice Wellness Index (VWI) application combining the acoustic voice quality index (AVQI) and glottal function index (GFI) data and to evaluate its reliability in quantitative voice assessment and normal versus pathological voice differentiation. Cross-sectional study. A total of 135 adult participants (86 patients with voice disorders and 49 patients with normal voices) were included in this study. Five iOS and Android smartphones with the "Voice Wellness Index" app installed were used to estimate VWI. The VWI data obtained using smartphones were compared with VWI measurements computed from voice recordings collected from a reference studio microphone. The diagnostic efficacy of VWI in differentiating between normal and disordered voices was assessed using receiver operating characteristics (ROC). With a Cronbach's alpha of 0.972 and an ICC of 0.972 (0.964-0.979), the VWI scores of the individual smartphones demonstrated remarkable inter-smartphone agreement and reliability. The VWI data obtained from different smartphones and a studio microphone showed nearly perfect direct linear correlations (r=0.993-0.998). Depending on the individual smartphone device used, the cutoff scores of VWI related to differentiating between normal and pathological voice groups were calculated as 5.6-6.0 with the best balance between sensitivity (94.10-95.15%) and specificity (93.68-95.72%), The diagnostic accuracy was excellent in all cases, with an area under the curve (AUC) of 0.970-0.974. The "Voice Wellness Index" application is an accurate and reliable tool for voice quality measurement and normal versus pathological voice screening and has considerable potential to be used by healthcare professionals and patients for voice assessment.

Separated and reunified: An apparent time investigation of the voice quality differences between Hong Kong Cantonese and Guangzhou Cantonese.

Hong Kong Cantonese (HKC) and Guangzhou Cantonese (GZC) are two major accents of Cantonese spoken in two geographically non-contiguous cities in Southern China. Previous studies were unable to identify the phonetic features that discern the two accents since they share the same phonological system. This study attempted to solve the puzzle by investigating the voice quality differences between the two accents through acoustic analysis on the speech output of 191 talkers in three age groups ranging from 18 to 65 years old. Among the various spectral and noise measurements of voice quality, we found that Cepstral Peak Prominence (CPP) was the best acoustic measure to discern the two accents. Based on the CPP measure, GZC had overall increased noise than HKC. Covariation of voice quality and tones was studied. The greatest CPP differences between the two accents were found in the two extreme tones: the high-level and the extra-low-level tones. Furthermore, creaky voice was found mainly tied to the extra-low-level tone in both accents. However, HKC exhibited higher frequency of creaky voice than GZC. The creaky voice in GZC was characterized by increased noise and increased tension, compared to those of HKC. Finally, age was found to be a mediating factor in the voice quality of the two accents. Adopting the Apparent Time Framework, voice quality in the two cities has undergone changes over time. The voice quality of the young generations of the two accents have become merged among the three low tones. Furthermore, the prevalence of creaky voice was increasing across age groups in both accents, and it increased at a faster rate in HKC than GZC.

Cross-linguistic realization of lateral ejective affricates in connected versus isolated speech

Typological research on ejectives has focused on the realization of stops in isolated speech (Kingston 1985, Lindau 1984). However, there has been little research on the realization of ejectives, and in particular affricates, in connected versus isolated speech. Given that lateral affricates can be produced with variable realization, this study compares the acoustics of [tɬ’] in isolated and connected speech for speakers of three languages: Lushootseed (Coast Salish), Hul’q’umi’num’ (Coast Salish), and Dene Kədə́ (Dene/Athabaskan). Duration, spectral moment, and voice quality measurements were examined from corpus data of word lists and connected speech. Results indicated that there was greater voice onset time (VOT), longer closure duration, and a smaller frication duration to VOT ratio in isolated speech than connected speech, supporting Lindblom’s (1990) and Farnetani & Recasens’ (2013) view that words are produced more hyperarticulated in isolated speech. Cross-linguistic differences were found in the duration of frication, center of gravity, and the rise to peak amplitude of the following vowel. Dene Kədə́ had greater frication duration and a shallower intensity slope than the Salish languages, indicators of differences in place of articulation and degree of affrication. This suggests different realizations of [tɬ’] across languages.

The Impact of Protective Face Coverings on Acoustic Markers in Voice: A Systematic Review and Meta-Analysis.

Wearing respiratory protective masks (RPMs) has become common worldwide, especially in healthcare settings, since the onset of the COVID-19 pandemic. Hypotheses have suggested that sound transmission could be limited by RPMs, which possibly affects the characteristics of acoustic energy and speech intelligibility. The objective of this study was to investigate the effect of RPMs on acoustic measurements through a systematic review with meta-analysis. Five database searches were conducted, ranging from their inception to August 2023, as well as a manual search. Cross-sectional studies were included that provided data on widely used gender-independent clinical acoustic voice quality measures (jitter, shimmer, HNR, CPPS, and AVQI) and habitual sound pressure level (SPL). We found nine eligible research studies with a total of 422 participants who were compared both without masks and with different types of masks. All included studies focused on individuals with vocally healthy voices, while two of the studies also included those with voice disorders. The results from the meta-analysis were related to medical/surgical and FFP2/(K)N95 masks. None of the acoustic measurements showed significant differences between the absence and presence of masks (p > 0.05). When indirectly comparing both mask types, statistical significance was identified for parameters of jitter, HNR, CPPS and SPL (p < 0.001). The present meta-analysis indicates that certain types of RPMs have no significant influence on common voice quality parameters and SPL compared to recordings without masks. Nevertheless, it is plausible that significant differences in acoustic parameters might exist between different mask types. Consequently, it is advisable for the clinical practice to always use the same mask type when using RPMs to ensure high comparability and accuracy of measurement results.

Effects of Vibratory Source on Auditory-Perceptual and Bio-Inspired Computational Measures of Pediatric Voice Quality

The vibratory source for voicing in children with dysphonia is classified into three categories including a glottal vibratory source (GVS) observed in those with vocal lesions or hyperfunction; supraglottal vibratory sources (SGVS) observed secondary to laryngeal airway injuries, malformations, or reconstruction surgeries; and a combination of both glottal and supraglottal vibratory sources called mixed vibratory source (MVS). This study evaluated the effects of vibratory source on three primary dimensions of voice quality (breathiness, roughness, and strain) in children with GVS, SGVS, and MVS using single-variable matching tasks and computational measures obtained from bio-inspired auditory models. A total of 44 dysphonic voice samples from children aged 4-11years were selected. Seven listeners rated breathiness, roughness, and strain of 1000-ms /ɑ/ samples using single-variable matching tasks. Computational estimates of pitch strength, amplitude modulation filterbank output, and sharpness were obtained through custom-designed MATLAB algorithms. Perceived roughness and strain were significantly higher in children with SGVS and MVS compared to children with GVS. Among the computational measures, only the modulation filterbank output resulted in significant differences among vibratory sources; a posthoc test revealed that children with SGVS had greater amplitude modulation than children with GVS, as expected from their rougher voice quality. The results indicate that the output of an auditory amplitude modulation filterbank model may capture characteristics of SGVS that are strongly related to the rough voice quality.

Reliability of Universal-Platform-Based Voice Screen Application in AVQI Measurements Captured with Different Smartphones.

The aim of the study was to develop a universal-platform-based (UPB) application suitable for different smartphones for estimation of the Acoustic Voice Quality Index (AVQI) and evaluate its reliability in AVQI measurements and normal and pathological voice differentiation. Our study group consisted of 135 adult individuals, including 49 with normal voices and 86 patients with pathological voices. The developed UPB "Voice Screen" application installed on five iOS and Android smartphones was used for AVQI estimation. The AVQI measures calculated from voice recordings obtained from a reference studio microphone were compared with AVQI results obtained using smartphones. The diagnostic accuracy of differentiating normal and pathological voices was evaluated by applying receiver-operating characteristics. One-way ANOVA analysis did not detect statistically significant differences between mean AVQI scores revealed using a studio microphone and different smartphones (F = 0.759; p = 0.58). Almost perfect direct linear correlations (r = 0.991-0.987) were observed between the AVQI results obtained with a studio microphone and different smartphones. An acceptable level of precision of the AVQI in discriminating between normal and pathological voices was yielded, with areas under the curve (AUC) displaying 0.834-0.862. There were no statistically significant differences between the AUCs (p > 0.05) obtained from studio and smartphones' microphones. The significant difference revealed between the AUCs was only 0.028. The UPB "Voice Screen" application represented an accurate and robust tool for voice quality measurements and normal vs. pathological voice screening purposes, demonstrating the potential to be used by patients and clinicians for voice assessment, employing both iOS and Android smartphones.

Judgements of a customer service agent's personality based on acoustic properties of their speech

People frequently interact with customer service agents, whether they are a real person or an AI, and quickly form personality impressions from it. The present study aimed to investigate how acoustic characteristics of speech of human agents affect their personality impressions. To this end, spontaneous speech was elicited from 30 native Korean speakers while they played a role of an agent assisting a customer on the phone. We then conducted a personality rating experiment in which 30 native speakers of Korean rated the perceived degree of extraversion, agreeableness, conscientiousness, neuroticism, and openness (the “Big Five” personality traits) on the recordings on a 5-point scale. Various acoustic features were extracted from the stimuli, which were converted into two principal components using a Principal Component Analysis. The results of correlation analyses demonstrated that some of the acoustic variables such as measures of voice quality (H1-H2, Harmonic-to-Noise Ratio), the mean f0, and articulation rate were significantly correlated with the personality ratings, with the acoustic correlates different for male and female speakers. This helps discover characteristics of a more likable voice and speaking style for a customer service agent and has important implications for generating more likable synthetic speech for similar services.

Auditory-perceptual Parameters as Predictors of Voice Acoustic Measures

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

Speaker-specificity in speech production: The contribution of source and filter

This study examines the extent to which speaker-specific information is encoded in different features of vocal output and the relationships between those features. A range of acoustic features, grouped as source (laryngeal voice quality measures and fundamental frequency) and filter features (formants and Mel-frequency cepstral coefficients; MFCCs), were extracted from the vocalic portion of the hesitation marker um for 90 male speakers of Standard Southern British English. Little overall correlation between the sets of features was observed, suggesting no strong interdependence between source and filter in our data. Although filter features were consistently better at discriminating between same- and different-speaker pairs compared with source features, combining source and filter has the potential of producing the lowest error rates and the strongest speaker discrimination scores. Taken together, results show that source and filter provide complementary speaker-specific information. However, the extent of the improvements in speaker discrimination performance when combining source and filter varied across speakers. We explore potential explanations for this finding and discuss the implications for source-filter theory, and for applied fields such as speaker recognition and forensic speech science.

Do We Get What We Need from Clinical Acoustic Voice Measurements?

Instrumental acoustic measurements of the human voice have enormous potential to objectively describe pathology and, thereby, to assist clinical treatment decisions. Despite the increasing application and accessibility of technical knowledge and equipment, recent research has highlighted a lack of understanding of physiologic, speech/language-, and culture-related influencing factors. This article presents a critical review of the current state of the art in the clinical application of instrumental acoustic voice quality measurements and points out future directions for improving its applications and dissemination in less privileged populations. The main barriers to this research relate to (a) standardization and reporting of acoustic analysis techniques; (b) understanding of the relation between perceptual and instrumental acoustic results; (c) the necessity to account for natural speech-related covariables, such as differences in speaking voice sound pressure level (SPL) and fundamental frequency f0; (d) the need for a much larger database to understand normal variability within and between voice-disordered and vocally healthy individuals related to age, training, and physiologic factors; and (e) affordable equipment, including mobile communication devices, accessible in various settings. This calls for further research into technical developments and optimal assessment procedures for pathology-specific patient groups.

Age-dependent treatment effect of vocal fold steroid injection for benign vocal fold lesions.

Benign vocal fold lesions (BVFLs) cause voice disorders and impair social life. Recently, office-based vocal fold steroid injection (VFSI) has gained attention as a minimally invasive treatment for BVFLs. This study aimed to analyze the age-dependent treatment effect of VFSI and to clarify the indications for treatment. In this retrospective cohort study, a total of 83 patients with BVFLs were treated with a similar regimen of VFSI. Three or four months after the injection, age-dependent phonological functions were evaluated. The differences between pre- and post-treatment findings were analyzed using the Wilcoxon matched-pair signed-rank test, and the correlation between patient age and improvement rates were determined by Pearson's correlation coefficient. Improvement in voice handicap index (VHI), which was the primary endpoint, was observed. Subjective and objective voice quality measurements also showed significant improvements. Subgroup analyses revealed that there was no age-related difference in the improvement of voice quality and that there was no improvement in aerodynamic effect in patients over 45 years of age. This study clarified the age-dependent treatment effect of VFSI and provided the important suggestion of establishing indication criteria for BVFLs. The study results provided clarity on the indication criteria of VFSI and served as an important indicator for tailoring treatment to patients' needs. 4.

Tele-rehabilitation in voice disorders during the pandemic: a consensus paper from the French Society of Phoniatrics and Laryngology.

To establish a consensus protocol for telerehabilitation in speech therapy for voice disorders. The study was conducted according to a modified Delphi method. Twenty speech therapist or laryngologist experts of the French Society of Phoniatrics and Laryngology assessed 24 statements of voice telerehabilitation with a 10-point visual analog scale ranging from 1 (totally disagree) to 10 (totally agree). The statements were accepted if more than 80% of the experts rated the item with a score of ≥ 8/10. The statements with ≥ 8/10 score by 60-80% of experts were improved and resubmitted to voting until they were validated or rejected. The French Society of Phoniatrics and Laryngology experts validated 10, 6, and 2 statements after the first, second and third voting round, respectively. Seven statements did not reach agreement threshold and were rejected. The validated statements included recommendations for setting (N = 4), medical/speech history (N = 2), subjective voice evaluations (N = 3), objective voice quality measurements (N = 3), and voice rehabilitation (N = 5). The experts agreed for a follow-up consisting of combined telerehabilitation and in-office rehabilitation. The final protocol may be applied in context of pandemic but could be assessed out of pandemic period for patients located in rural regions. This Delphi study established the first telerehabilitation protocol of the French Society of Phoniatrics and Laryngology for patients with voice disorders. Future controlled studies are needed to assess its feasibility, reliability, and the patient perception about telerehabilitation versus in-office rehabilitation.

Measures of Voice Quality as Indicators of Mild Cognitive Impairment

AbstractBackgroundNoticeable decline in communication skills of patients with Alzheimer’s disease are often observed in the early stages of the disease, years before the dementia emerges. Prior literature has identified language abnormalities such as decline of linguistic ability or syntactic deficits influenced by the cognitive impairment. While language‐related measures are able to characterize spoken words of speech samples, they are inherently incapable of quantifying the voice‐related properties such as emotion or voice quality. Focusing on automatically derived voice‐based biomarkers that reflect the voicing quality of speakers, our objective is to explore the usefulness of these measures at detecting mild cognitive impairment (MCI) as early indicators of MCI in machine learning models. We hypothesize that cognitive impairment influences the individual’s voice quality resulting in an abnormal periodicity in speech often known as vocal dysperiodicity.MethodWe analyzed acoustic properties of audio‐recordings of Craft Story test administered to 107 subjects (50 MCI and 57 healthy controls, mean age 81 yrs) from a recently completed randomized control trial aimed to enhance cognitive reserve by increasing social interactions using video‐chats (www.I-conect.org). In the Craft Story test, the examiner reads a short story to the participant who is asked to retell the story first immediately after hearing the story and next retell it after a 20‐minute delay. Using cepstral analysis method, we extracted cepstrum from both immediate recall (IR) and delayed recall (DR) tests, and utilized statistical measures to represent their acoustic characteristics. We also used recursive feature elimination to only select informative measures and utilized the support vector machine for building classification models.ResultCepstrum‐based Measures derived from the IR test achieved higher predictive ability than those derived from the DR test. Combining the measures derived from both IR and DR tests increased the classification results and achieved ROC AUC of 98.83% and 97.09% on gender‐balanced models trained on males and females, respectively.ConclusionOur results indicate that voice‐based measures are capable of detecting MCI from audio samples of the Craft Story capitalizing their potential use in automatic screening and telemonitoring of the disorder in research, clinical trials and ultimately clinical practice.

Voice Quality in Telephone Interviews: A preliminary Acoustic Investigation

To investigate the impact of standardized mobile phone recordings passed through a telecom channel on acoustic markers of voice quality and on its perception by voice experts in normophonic speakers. Continuous speech and a sustained vowel were recorded for fourteen female and ten male normophonic speakers. The recordings were done simultaneously with a head-mounted high-quality microphone and through the telephone network on a receiving smartphone. Twenty-two acoustic voice quality, breathiness and pitch-related measures were extracted from the recordings. Nine vocologists perceptually rated the G, R and B parameters of the GRBAS scale on each voice sample. The reproducibility, the recording type, the stimulus type and the gender effects, as well as the correlation between acoustic and perceptual measures were investigated. The sustained vowel samples are damped after one second. Only the frequencies between 100 and 3700Hz are passed through the telecom channel and the frequency response is characterized by peaks and troughs. The acoustic measures show a good reproducibility over the three repetitions. All measures significantly differ between the recording types, except for the local jitter, the harmonics-to-noise ratio by Dejonckere and Lebacq, the period standard deviation and all six pitch measures. The AVQI score is higher in telephone recordings, while the ABI score is lower. Significant differences between genders are also found for most of the measures; while the AVQI is similar in men and women, the ABI is higher in women in both recording types. For the perceptual assessment, the interrater agreement is rather low, while the reproducibility over the three repetitions is good. Few significant differences between recording types are observed, except for lower breathiness ratings on telephone recordings. G ratings are significantly more severe on the sustained vowel on both recording types, R ratings only on telephone recordings. While roughness is rated higher in men on telephone recordings by most experts, no gender effect is observed for breathiness on either recording types. Finally, neither the AVQI nor the ABI yield strong correlations with any of the perceptual parameters. Our results show that passing a voice signal through a telecom channel induces filter and noise effects that limit the use of common acoustic voice quality measures and indexes. The AVQI and ABI are both significantly impacted by the recording type. The most reliable acoustic measures seem to be pitch perturbation (local jitter and period standard deviation) as well as the harmonics-to-noise ratio from Dejonckere and Lebacq. Our results also underline that raters are not equally sensitive to the various factors, including the recording type, the stimulus type and the gender effects. Neither of the three perceptual parameters G, R and B seem to be reliably measurable on telephone recordings using the two investigated acoustic indexes. Future studies investigating the impact of voice quality in telephone conversations should thus focus on acoustic measures on continuous speech samples that are limited to the frequency response of the telecom channel and that are not too sensitive to environmental and additive noise.

Evaluating a Vibratory Positive Expiratory Pressure (PEP) Device as a Dysphonia Treatment

<h2>Summary</h2><h3>Introduction</h3> Previous work investigating Acapella Choice, a vibratory positive expiratory pressure device, as a form of semi-occluded vocal tract exercise (SOVTE) identified that it promoted large oscillatory pressures and promoted improved vocal economy for normophonic volunteers. Its use in a pathological population has not yet been investigated. <h3>Objectives</h3> To assess the impact of Acapella Choice as an SOVTE in a group of dysphonic patients and compare outcomes to tube-in-water resistance therapy. <h3>Methods</h3> Thirty participants underwent acoustic, electroglottography (EGG) and aerodynamic assessment before and after 3 minutes of phonation with Acapella Choice and with a 9 mm diameter tube in 5 cm of water (WRT). During exercise, aerodynamic and EGG signals were captured simultaneously. Descriptive statistics and tests of significant differences between groups and exercises were carried out. Outcome variables included expert-rated voice quality, sound pressure level, difference in first and second harmonics (H1-H2), cepstral peak prominence, mean contact quotient (CQ), mean peak pressure, mean flow during voicing, laryngeal resistance and aerodynamic power. Participants rated their perceived vocal clarity, strength, and effortlessness as well as vocal tract discomfort utilizing the Vocal Tract Discomfort Scale. <h3>Results and Conclusions</h3> Participants were clustered based on baseline laryngeal resistance, resulting in a high resistance (HR, n = 14) and low resistance (LR, n = 16) groups. Acapella produced twice the static intraoral pressure and oscillatory (root mean square) pressure and flow compared to WRT. Both exercises produced similar static flows. Acapella oscillation frequency was higher than WRT bubbling, but not meaningfully. Flow increased significantly from pre-intervention levels to perform both exercises, and further increased during the task. The glottal response of the groups was categorically different; the HR group had an immediate drop in CQ commencing both tasks, while the LR group demonstrated a steady decline in CQ in Acapella only. Following Acapella, CQ and H1-H2 trended towards normalization. Acapella also produced larger aerodynamic changes. Measures of voice quality deteriorated modestly following both exercises. By contrast, participant ratings of voice production were significantly improved after both tasks, more so with Acapella. The HR group reported significant reductions in tightness and aching following Acapella. Participants favored Acapella, finding it more practical and more likely to be used for daily practice.

Guidance to the Praat, a Software for Speech and Acoustic Analysis

Praat is a useful analysis tool for linguists, engineers, doctors, speech-language pathologits, music majors, and natural scientists. Basic parameters including duration, pitch, energy and perturbation parameters such as jitter and shimmer can be easily measured and manipulated in the sound editor. When a more in-depth analysis is needed, it is recommended to understand the advanced menus of the object window and learn how to use them. Among the object window menus, vowel formant analysis, spectrum analysis, and cepstrum analysis can be cited as useful ones in the clinical field. The spectrum object can be usefully used for voice quality measurement and diagnosis of patients with voice disorders by showing the energy distribution according to frequency axis (domain). A cepstrum object is useful for speech analysis when periodicity of the sound object is not measurable. The low to high ratio obtained from the spectral object and the CPPs measured from the cepstrum object have attracted many researchers, and it has been proven that the CPPs measured in Praat are relatively excellent.

An iOS-based VoiceScreen application: feasibility for use in clinical settings-a pilot study.

To elaborate the application suitable for smartphones for estimation of Acoustic Voice Quality Index (AVQI) and evaluate its usability in the clinical setting. An elaborated AVQI automatization and background noise monitoring functions were implemented into a mobile "VoiceScreen" application running the iOS operating system. A study group consisted of 103 adult individuals with normal voices (n = 30) and 73 patients with pathological voices. Voice recordings were performed in the clinical setting with "VoiceScreen" app using iPhone 8 microphones. Voices of 30 patients were recorded before and 1month after phonosurgical intervention. To evaluate the diagnostic accuracy differentiating normal and pathological voice, the receiver-operating characteristic statistics, i.e., area under the curve (AUC), sensitivity and specificity, and correct classification rate (CCR) were used. A high level of precision of AVQI in discriminating between normal and dysphonic voices was yielded with corresponding AUC = 0.937. The AVQI cutoff score of 3.4 demonstrated a sensitivity of 86.3% and specificity of 95.6% with a CCR of 89.2%. The preoperative mean value of the AVQI [6.01(SD 2.39)] in the post-phonosurgical follow-up group decreased to 2.00 (SD 1.08). No statistically significant differences (p = 0.216) between AVQI measurements in a normal voice and 1-month follow-up after phonosurgery groups were revealed. The "VoiceScreen" app represents an accurate and robust tool for voice quality measurement and demonstrates the potential to be used in clinical settings as a sensitive measure of voice changes across phonosurgical treatment outcomes.