Search

Phonatory instabilities and involuntary register transitions can occur during singing. However, little is known regarding the mechanisms which govern such transitions. To investigate this phenomenon, we systematically varied laryngeal muscle activation and airflow in an in vivo canine larynx model during phonation. We calculated voice range profiles showing average nerve activations for all combinations of fundamental frequency (F0) and sound pressure level (SPL). Further, we determined closed-quotient (CQ) and minimum-posterior-area (MPA) based on high-speed video recordings. While different combinations of muscle activation favored different combinations of F0 and SPL, in the investigated larynx there was a consistent region of instability at about 400 Hz which essentially precluded phonation. An explanation for this region may be a larynx specific coupling between sound source and subglottal tract or an effect based purely on larynx morphology. Register transitions crossed this region, with different combinations of cricothyroid and thyroarytenoid muscle (TA) activation stabilizing higher or lower neighboring frequencies. Observed patterns in CQ and MPA dependent on TA activation reproduced patterns found in singers in previous work. Lack of control of TA stimulation may result in phonation instabilities, and enhanced control of TA stimulation may help to avoid involuntary register transitions, especially in the singing voice.

Objectives: Maximum phonation time is a simple test used to assess glottic competency. Our objective was to evaluate any correlation between maximum phonation time and spasmodic dysphonia as adductor spasmodic dysphonia and abductor spasmodic dysphonia have an adductor and abductor overdrive, respectively. Methods: A 3-year data-review was performed for patients diagnosed with adductor spasmodic dysphonia, abductor spasmodic dysphonia and mixed spasmodic dysphonia. Maximum phonation time was noted on the first visit and compared with a control group. Results: Average maximum phonation time in adductor spasmodic dysphonia, abductor spasmodic dysphonia and control group was 25 seconds, 9 seconds and 16 seconds. A significant difference was found for adductor spasmodic dysphonia and abductor spasmodic dysphonia. A receiver operating characteristic curve analysis between adductor spasmodic dysphonia and control groups showed a positive predictive value of 81.3 per cent, negative predictive value of 83.9 per cent, sensitivity of 79.6 per cent and specificity of 85.2 per cent. Level of evidence = 4. Conclusion: We recommend that maximum phonation time be added to the diagnostic armamentarium of spasmodic dysphonia. This correlation between maximum phonation time and spasmodic dysphonia has not been previously published. [ABSTRACT FROM AUTHOR]

Prevalence estimates of Parkinson's disease (PD)—the fastest-growing neurodegenerative disease—are generally underestimated due to issues surrounding diagnostic accuracy, symptomatic undiagnosed cases, suboptimal prodromal monitoring, and limited screening access. Remotely monitored wearable devices and sensors provide precise, objective, and frequent measures of motor and non-motor symptoms. Here, we used consumer-grade wearable device and sensor data from the WATCH-PD study to develop a PD screening tool aimed at eliminating the gap between patient symptoms and diagnosis. Early-stage PD patients (n = 82) and age-matched comparison participants (n = 50) completed a multidomain assessment battery during a one-year longitudinal multicenter study. Using disease- and behavior-relevant feature engineering and multivariate machine learning modeling of early-stage PD status, we developed a highly accurate (92.3%), sensitive (90.0%), and specific (100%) random forest classification model (AUC = 0.92) that performed well across environmental and platform contexts. These findings provide robust support for further exploration of consumer-grade wearable devices and sensors for global population-wide PD screening and surveillance. [ABSTRACT FROM AUTHOR]

Objective: Open partial horizontal laryngectomies (OPHLs) represent a comparable alternative to total laryngectomy and nonsurgical protocols in selected cases. While short‐term functional outcomes of OPHLs have been widely investigated, few have focused on the effect of aging on residual laryngeal structures. Study Design: Retrospective cohort study. Setting: Tertiary care academic center. Methods: Patients who underwent OPHLs after at least 1 year follow‐up and optimal functional rehabilitation were included in the study. Swallowing function was assessed according to PAS (Penetration aspiration scale) and Pooling scores. Spectrogram analysis of voice was conducted according to Yanagihara classification and acoustic parameters were also recorded. Subjective questionnaire data about phonation and swallowing were also recorded. Data obtained were compared among patients according to age at time of surgery, evaluation and duration of follow‐up. Results: Ninety‐seven patients were enrolled with a mean age at surgery and evaluation of 63 and 70 years old, respectively. Median follow‐up length was 5 years. OPHL type II was mostly performed. No significant correlation was observed between most of the analyzed variables and patient's age at the time of surgery and at the time of evaluation. Some acoustic parameters were negatively correlated with follow‐up length, while Jitter, NHR (Noise‐Harmonic Ratio), and Global grade and Roughness were significantly higher in patients >65 years old. Conclusion: Patients who complete rehabilitation reach equally good results as their younger peers with stability over time. Finally, the effects of aging on residual larynx are of minor entity compared to the nonoperated patients. Level of Evidence: Level IV‐retrospective cohort study. [ABSTRACT FROM AUTHOR]

The goal of this computational study is to quantify global effects of vocal tract constriction at various locations (false vocal folds, aryepiglottic folds, pharynx, oral cavity, and lips) on the voice source across a large range of vocal fold conditions. The results showed that while inclusion of a uniform vocal tract had notable effects on the voice source, further constricting the vocal tract only had small effects except for conditions of extreme constriction, at which constrictions at any location along the vocal tract decreased the mean and peak-to-peak amplitude of the glottal flow waveform. Although narrowing in the epilarynx increased the normalized maximum flow declination rate, vocal tract constriction in general slightly reduced the source strength and high-frequency harmonic production at the glottis, except for a limited set of vocal fold conditions (e.g., soft, long vocal folds subject to relatively high pressure). This suggests that simultaneous laryngeal and vocal tract adjustments are required to maximize source-filter interaction. While vocal tract adjustments are often assumed to improve voice production, our results indicate that such improvements are mainly due to changes in vocal tract acoustic response rather than improved voice production at the glottis.

Three laryngeal models were used to investigate the aerodynamic and elastic properties of vocal fold vibration: cadaveric human, excised canine, and synthetic silicone vocal folds. The aim was to compare the characteristics of these models to enhance our understanding of phonatory mechanisms. Flow and medial glottal wall geometry were acquired via particle image velocimetry. Elastic properties were assessed from force–displacement tests. Relatively, the human larynges had higher fundamental frequency values, while canine and synthetic models exhibited greater flow rates. Canine models demonstrated the highest divergence angles and vertical stiffness gradients followed by the human model, both displaying flow separation vortices during closing. Synthetic models, whose advantage is their accessibility and repeatability, displayed the lowest glottal divergence angles and total circulation values compared to tissue models with no flow separation vortices. The elasticity tests revealed that tissue models showed significant hysteresis and vertical stiffness gradients, unlike the synthetic models. These results underscore the importance of model selection based on specific research needs and highlight the potential of canine and synthetic models for controlled experimental studies in phonation. [ABSTRACT FROM AUTHOR]

Objectives: Injury to the external branch of the superior laryngeal nerve (EBSLN) causes low‐pitch voice and voice fatigue, particularly in female subjects, and available treatments are limited. Here, we assess a novel surgical procedure to restore a high‐tone voice: ansa cervicalis to EBSLN anastomosis (A‐E anastomosis). Methods: Between November 2012 and April 2022, 13 patients (12 female) underwent unilateral EBSLN resection and A‐E anastomosis, while 20 (16 female) underwent EBSLN resection during thyroid surgery. Patients (4494 women and 1025 men) with normal laryngoscopy scheduled for thyroid surgery served as normal controls. Phonatory function was examined using a Phonation Analyzer PA‐1000 preoperatively and intermittently postoperatively. Results: In patients who underwent A‐E anastomosis, high‐tone voice pitch decreased significantly postoperatively (673.9–471.5 Hz, p = 0.047), with restoration achieved within 5 months. The mean voice pitch in female patients who underwent A‐E anastomosis, EBSLN resection, and controls were 580.4, 522.8, and 682.0 Hz, respectively, indicating a significant decrease in EBSLN resection patients than controls (p = 0.002). The (mean – 1SD) of high‐tone voice pitch in female controls was 497 Hz; exceeding this may indicate recovery to a high‐tone voice. Overall, 73% (8/11) of A‐E anastomosis patients exceeded this value, which was marginally larger than the 43% (6/14) who underwent EBSLN resection. Data on male subjects are limited. There were no cases of adverse functional or cosmetic events. Conclusions: A‐E anastomosis, a novel simple procedure, restored high‐tone voice to some extent without any adverse events and thus warrants further investigation. Level of Evidence: 3 Laryngoscope, 134:3868–3873, 2024 [ABSTRACT FROM AUTHOR]

Objective: To evaluate the outcomes of reinnervation techniques for the treatment of adult unilateral vocal fold paralysis and bilateral vocal fold paralysis. Methods: A literature review was conducted in the Embase and Medline databases in English, with no limitations on the publication date. The outcome parameters of interest included visual, subjective perceptual, acoustic, aerodynamic analysis and electromyography. A meta-analysis with a random-effects model and inverse variance was calculated. Results: The systematic Preferred Reporting Items for Systematic Reviews and Meta-Analyses approach resulted in 27 studies, totalling 803 patients (747 unilateral cases and 56 bilateral cases). Thyroid cancer and/or surgery had caused unilateral vocal fold paralysis in 74.8 per cent of cases and bilateral vocal fold paralysis in 69.6 per cent of cases. Statistically significant improvements in patients were observed for voice, deglutition and decannulation (bilateral vocal fold paralysis). Meta-analysis of 10 reinnervation techniques was calculated for the maximum phonation time of 184 patients. Conclusion: Reinnervation was shown to improve voice, swallowing and decannulation, but studies lacked control groups, limiting generalisability. Larger studies with controls are needed. [ABSTRACT FROM AUTHOR]

Speech alterations have been reported in manifest Huntington's disease (HD) and premanifest mutation carriers (preHD). The aim of our study was to explore these alterations in preHD and whether they can be used as biomarkers. 13 preHD mutation carriers performed reading task, sustained phonation task and syllable repetition tasks at baseline and after 21 months, as well as clinical examination and MRI. Syllable repetition capacity and self-chosen velocity of single syllable repetition differed significantly between time points. There were no changes in clinical ratings or MRI volumetry. Measurements of speech might be sensitive tools for monitoring subclinical changes in preHD. [ABSTRACT FROM AUTHOR]

The study of animal sounds in biology and ecology relies heavily upon time–frequency (TF) visualisation, most commonly using the short‐time Fourier transform (STFT) spectrogram. This method, however, has inherent bias towards either temporal or spectral details that can lead to misinterpretation of complex animal sounds. An ideal TF visualisation should accurately convey the structure of the sound in terms of both frequency and time, however, the STFT often cannot meet this requirement. We evaluate the accuracy of four TF visualisation methods (superlet transform [SLT], continuous wavelet transform [CWT] and two STFTs) using a synthetic test signal. We then apply these methods to visualise sounds of the Chagos blue whale, Asian elephant, southern cassowary, eastern whipbird, mulloway fish and the American crocodile. We show that the SLT visualises the test signal with 18.48%–28.08% less error than the other methods. A comparison between our visualisations of animal sounds and their literature descriptions indicates that the STFT's bias may have caused misinterpretations in describing pygmy blue whale songs and elephant rumbles. We suggest that use of the SLT to visualise low‐frequency animal sounds may prevent such misinterpretations. Finally, we employ the SLT to develop 'BASSA', an open‐source, GUI software application that offers a no‐code, user‐friendly tool for analysing short‐duration recordings of low‐frequency animal sounds for the Windows platform. The SLT visualises low‐frequency animal sounds with improved accuracy, in a user‐friendly format, minimising the risk of misinterpretation while requiring less technical expertise than the STFT. Using this method could propel advances in acoustics‐driven studies of animal communication, vocal production methods, phonation and species identification. [ABSTRACT FROM AUTHOR]

This article provides a detailed examination of voice quality in word-final vowels in Spanish. The experimental task involved the pronunciation of words in two prosodic contexts by native Spanish speakers from diverse dialects. A total of 400 vowels (10 participants × 10 words × 2 contexts × 2 repetitions) were analyzed acoustically in Praat. Waveforms and spectrograms were inspected visually for voice, creak, breathy voice, and devoicing cues. In addition, the relative amplitude difference between the first two harmonics (H1–H2) was obtained via FFT spectra. The findings reveal that while creaky voice is pervasive, breathy voice is also common, and devoicing occurs in 11% of tokens. We identify multiple phonation types (up to three) within the same vowel, of which modal voice followed by breathy voice was the most common combination. While creaky voice was more frequent overall for males, modal voice tended to be more common in females. In addition, creaky voice was significantly more common at the end of higher prosodic constituents. The analysis of spectral tilt shows that H1–H2 clearly distinguishes breathy voice from modal voice in both males and females, while H1–H2 values consistently discriminate creaky and modal voice in male participants only. [ABSTRACT FROM AUTHOR]

ObjectiveWhile the vocal fold is in direct contact anteriorly with the thyroid cartilage, posteriorly the vocal fold connects to the thyroid cartilage through a soft tissue layer in the paraglottic space. Currently the paraglottic space is often neglected in computational models of phonation, in which a fixed boundary condition is often imposed on the lateral surface of the vocal fold. The goal of this study was to investigate the effect of the paraglottic space on voice production in an MRI-based vocal fold model, and how this effect may be counteracted by vocal fold stiffening due to laryngeal muscle activation.MethodsParametric simulation study using an MRI-based computational vocal fold model.ResultsThe results showed that the presence of the paraglottic space increased the mean and amplitude of the glottal area waveform, decreased the phonation frequency and closed quotient. For the particular vocal fold geometry used in this study, the presence of the paraglottic space also reduced the occurrence of irregular vocal fold vibration. These effects of the paraglottic space became smaller with increasing paraglottic space stiffness and to a lesser degree with vocal fold stiffening.ConclusionsThe results suggest that the paraglottic space may be neglected in qualitative evaluations of normal phonation, but needs to be included in simulations of pathological phonation or vocal fold posturing.

ObjectiveEstimation of physiological control parameters of the vocal system from the produced voice outcome has important applications in clinical management of voice disorders . Previously we developed a simulation-based neural network for estimation of vocal fold geometry, mechanical properties, and subglottal pressure from voice outcome features that characterize the acoustics of the produced voice. The goals of this study are to (1) explore the possibility of improving the estimation accuracy of physiological control parameters by including voice outcome features characterizing vocal fold vibration; and (2) identify voice feature sets that optimize both estimation accuracy and robustness to measurement noise.MethodsFeedforward neural networks are trained to solve the inversion problem of estimating the physiological control parameters of a three-dimensional body-cover vocal fold model from different sets of voice outcome features that characterize the simulated voice acoustics, glottal flow, and vocal fold vibration. A sensitivity analysis is then performed to evaluate the contribution of individual voice features to the overall performance of the neural networks in estimating the physiologic control parameters.Results and conclusionsWhile including voice outcome features characterizing vocal fold vibration increases estimation accuracy, it also reduces the network's robustness to measurement noise, due to high sensitivity of network performance to voice outcome features measuring the absolute amplitudes of the glottal flow and area waveforms, which are also difficult to measure accurately in practical applications. By excluding such glottal flow-based features and replacing glottal area-based features by their normalized counterparts, we are able to significantly improve both estimation accuracy and robustness to noise. We further show that similar estimation accuracy and robustness can be achieved with an even smaller set of voice outcome features by excluding features of small sensitivity.

IntroductionAlthough phonatory glottal posture and airflow pulse shape affect voice quality, studies to date have been limited by visualization of vocal fold (VF) vibration from a superior view. We performed a 3D reconstruction of VF vibratory motion during phonation from a medial view and assessed the glottal volume waveform and resulting acoustics as a function of neuromuscular stimulation.Study designIn vivo canine hemilarynx phonation.MethodsAcross 121 unique combinations of the superior laryngeal nerve (SLN) and recurrent laryngeal nerve (RLN) stimulation, the hemilarynx was excited to the oscillation with airflow. VF medial surface reference points were tracked on high-speed video, mapped into 3D space, and surface shape was restored using cubic spline interpolation. Glottal surface shape, reconstruction-based parameters, and glottal volume waveform were calculated. Fundamental frequency (F0), cepstral peak prominence (CPP), and harmonic amplitude (H1-H2) were measured from high-quality audio samples.ResultsThe glottis was convergent during opening and divergent during closing. Neuromuscular activation changed phonatory glottal shape and reduced glottal volume. Significant reduction in glottal volume and closing quotient were present with SLN stimulation. RLN stimulation significantly increased F0 and CPP and decreased H1-H2 (constricted glottis), while SLN effects were similar and synergistic with concurrent RLN stimulation.Conclusion3D reconstruction of in vivo medial surface vibration revealed effects of laryngeal nerve stimulation on glottal vibratory pattern and acoustic correlates of voice quality. SLN activation resulted in significantly quicker glottal closure per cycle, decreased glottal volume, and higher-pitched, less breathy, and less noisy voice. RLN had a similar effect on acoustic measures.Level of evidenceNA, Basic Science Laryngoscope, 133:357-365, 2023.

Laryngeal mucus hydrates and lubricates the deformable tissue of the vocal folds and acts as a boundary layer with the airflow from the lungs. However, the effects of the mucus' viscoelasticity on phonation remain widely unknown and mucus has not yet been established in experimental procedures of voice research. In this study, four synthetic mucus samples were created on the basis of xanthan with focus on physiological frequency-dependent viscoelastic properties, which cover viscosities and elasticities over 2 orders of magnitude. An established ex vivo experimental setup was expanded by a reproducible and controllable application method of synthetic mucus. The application method and the suitability of the synthetic mucus samples were successfully verified by fluorescence evidence on the vocal folds even after oscillation experiments. Subsequently, the impact of mucus viscoelasticity on the oscillatory dynamics of the vocal folds, the subglottal pressure, and acoustic signal was investigated with 24 porcine larynges (2304 datasets). Despite the large differences of viscoelasticity, the phonatory characteristics remained stable with only minor statistically significant differences. Overall, this study increased the level of realism in the experimental setup for replication of the phonatory process enabling further research on pathological mucus and exploration of therapeutic options.

While the phenomenon of tonogenesis is well represented in the literature, diachronic tone change in already-tonal languages has received less attention. This paper considers two types of tonal morphology used to mark the "potential" inflectional category on verbs in Coatec Zapotec (aka Di′zhke′). Some verbs are marked with upstep. Coatec upstepped tones are emergent tonal contrasts that are developing out of high register allotones which assimilated to a historical high tone on a now-deleted preceding syllable. Other verbs display patterns of tone ablaut such that a verb with underlying low or falling tone surfaces with high or rising in the potential. Both upstep and tone ablaut in Coatec can be traced to an earlier floating high tone that could dock onto different syllables according to a set of ranked constraints. Using a combination of internal and comparative reconstruction, details of the earlier tonal system are revealed. This is the first published treatment of Proto-Zapotec tone since Swadesh (1947) and the first paper to address tone in Proto-Zapotecan and Proto Core Zapotec. *ʔ is revealed to have been a consonant through the Core Zapotec period, suggesting that the complex systems of phonation contrasts found in some Central Zapotec languages are a recent development. Cases of tonal contrasts developing out of phonation contrasts are known from Southeast Asia, but Zapotec phonation contrasts arose out of interaction between the glottal consonant and pre-existing tonal contrasts. An exploration of the morphological environments conducive to upstep leads to new discoveries about Zapotecan derivational voice prefixes and reveals the origins of perfective allomorphy. [ABSTRACT FROM AUTHOR]

Background: Hyperosmolar aerosols appear to promote or suppress upper airway dysfunction caused by dehydration in a composition-dependent manner. We sought to explore this composition dependence experimentally, in an interventional human clinical study, and theoretically, by numerical analysis of upper airway ion and water transport. Methods: In a double-blinded, placebo-controlled clinical study, phonation threshold pressure (PTP) was measured prenasal and postnasal inhalation of hypertonic aerosols of NaCl, KCl, CaCl2, and MgCl2 in seven human subjects. Numerical analysis of water and solute exchanges in the upper airways following deposition of these same aerosols was performed using a mathematical model previously described in the literature. Results: PTP decreased by 9%–22% relative to baseline (p < 0.05) for all salts within the first 30 minutes postadministration, indicating effective laryngeal hydration. Only MgCl2 reduced PTP beyond 90 minutes (21% below baseline at 2 hours postadministration). By numerical analysis, we determined that, while airway water volume up to 15 minutes postdeposition is dictated by osmolarity, after 30 minutes, divalent cation salts, such as MgCl2, better retain airway surface liquid (ASL) volume by slow paracellular clearance of the divalent cation. Fall of CFTR chloride flux with rise in ASL height, a promoter of airway acidification, appears to be a signature of permeating cation (NaCl) and nonpermeating anion (mannitol) aerosol deposition. For hypertonic aerosols that lack permeating cation and include permeating anion (CaCl2 and MgCl2), this acid-trigger signature does not exist. Conclusions: Nonpermeating cation and permeating anion hypertonic aerosols appear to hydrate upper airways longer and, rather than provoke, may reduce laryngeal dysfunction such as cough and bronchoconstriction. [ABSTRACT FROM AUTHOR]

Singing is defined as a sensory-motor phenomenon that requires particular balanced physical skills such as respiration, phonation, resonance, and articulation. The long-term average spectrum (LTAS) is widely accepted as a robust and effective tool for the assessment of voice characteristics. Eighty female singers within the age range of 18-30 year s were considered for the study. Among 80 participants, 40 were asked to perform one traditional song from Bangla Folk representing the Baul style and another 40 were asked to perform a traditional song from Rabindra Sangeet. Recordings were done and then acoustic (LTAS) analyses were done through PRAAT software. Statistical analyses were done for the analyzed data. software package of social sciences (Version 20.0) was used. The averaged LTAS curve of Baul style showed a broad peak in the frequency range between 2000 and 3600Hz and its amplitude about 16 dB, Rabindra Sangeet showed a broader peak in the frequency range between 2200 and 3800 Hz and its amplitude about 15 dB. This evidence showed the presence of singer's formants in both singing styles. It can be concluded from the present study that, there is an acoustical difference between the Bangla Folk and Rabindra Sangeet singing style which can be evidenced using LTAS through PRAAT. [ABSTRACT FROM AUTHOR]

Abstract The study of animal sounds in biology and ecology relies heavily upon time–frequency (TF) visualisation, most commonly using the short‐time Fourier transform (STFT) spectrogram. This method, however, has inherent bias towards either temporal or spectral details that can lead to misinterpretation of complex animal sounds. An ideal TF visualisation should accurately convey the structure of the sound in terms of both frequency and time, however, the STFT often cannot meet this requirement. We evaluate the accuracy of four TF visualisation methods (superlet transform [SLT], continuous wavelet transform [CWT] and two STFTs) using a synthetic test signal. We then apply these methods to visualise sounds of the Chagos blue whale, Asian elephant, southern cassowary, eastern whipbird, mulloway fish and the American crocodile. We show that the SLT visualises the test signal with 18.48%–28.08% less error than the other methods. A comparison between our visualisations of animal sounds and their literature descriptions indicates that the STFT's bias may have caused misinterpretations in describing pygmy blue whale songs and elephant rumbles. We suggest that use of the SLT to visualise low‐frequency animal sounds may prevent such misinterpretations. Finally, we employ the SLT to develop ‘BASSA’, an open‐source, GUI software application that offers a no‐code, user‐friendly tool for analysing short‐duration recordings of low‐frequency animal sounds for the Windows platform. The SLT visualises low‐frequency animal sounds with improved accuracy, in a user‐friendly format, minimising the risk of misinterpretation while requiring less technical expertise than the STFT. Using this method could propel advances in acoustics‐driven studies of animal communication, vocal production methods, phonation and species identification.

While the glottal flow is often simplified as one-dimensional (1D) in computational models of phonation to reduce computational costs, the 1D flow model has not been validated in left-right asymmetric vocal fold conditions, as often occur in both normal and pathological voice production. In this study, we performed three-dimensional (3D) and 1D flow simulations coupled to a two-mass model of adult male vocal folds and compared voice production at different degrees of left-right stiffness asymmetry. The flow and acoustic fields in 3D were obtained by solving the compressible Navier-Stokes equations using the volume penalization method with the moving vocal fold wall as an immersed boundary. Despite differences in the predicted flow pressure on vocal fold surface between the 1D and 3D flow models, the results showed reasonable agreement in vocal fold vibration patterns and selected voice outcome measures between the 1D and 3D models for the range of left-right asymmetric conditions investigated. This indicates that vocal fold properties play a larger role than the glottal flow in determining the overall pattern of vocal fold vibration and the produced voice, and the 1D flow simplification is sufficient in modeling phonation, at least for the simplified glottal geometry of this study.

Objectives Emotions and stress affect voice production. There are only a few reports in the literature on how changes in the autonomic nervous system affect voice production. The aim of this study was to examine emotions and measure stress reactions during a voice examination procedure, particularly changes in the muscles surrounding the larynx. Material and Methods The study material included 50 healthy volunteers (26 voice workers – opera singers, 24 control subjects), all without vocal complaints. All subjects had good voice quality in a perceptual assessment. The research procedure consisted of 4 parts: an ear, nose, and throat (ENT)‑phoniatric examination, surface electromyography, recording physiological indicators (heart rate and skin resistance) using a wearable wristband, and a psychological profile based on questionnaires. Results The results of the study demonstrated that there was a relationship between positive and negative emotions and stress reactions related to the voice examination procedure, as well as to the tone of the vocal tract muscles. There were significant correlations between measures describing the intensity of experienced emotions and vocal tract muscle maximum amplitude of the cricothyroid (CT) and sternocleidomastoid (SCM) muscles during phonation and non-phonation tasks. Subjects experiencing eustress (favorable stress response) had increased amplitude of submandibular and CT at rest and phonation. Subjects with high levels of negative emotions, revealed positive correlations with SCM max during the glissando. The perception of positive and negative emotions caused different responses not only in the vocal tract but also in the vegetative system. Correlations were found between emotions and physiological parameters, most markedly in heart rate variability. A higher incidence of extreme emotions was observed in the professional group. Conclusions The activity of the vocal tract muscles depends on the type and intensity of the emotions and stress reactions. The perception of positive and negative emotions causes different responses in the vegetative system and the vocal tract. Int J Occup Med Environ Health. 2024;37(1):84–97

Background: This paper reports the innovative use of a modified nasopharyngeal airway device as a temporary stent in patients with laryngotracheal stenosis. It also discusses the technique of endoscopic stent placement, and our experience in terms of the indications and suitability. Method: The nasopharyngeal airway device was modified to use as an airway stent by trimming it to the desired length. Next, the stent was inserted endoscopically and anchored using a novel approach. Results: The surgery was performed successfully without complications. The patients had full use of their voice while the stent was in situ. No significant granulation tissue was observed. Conclusion: This paper demonstrates the feasibility of using a nasopharyngeal airway device as a temporary stent to prevent restenosis in cases where the patients have a strong demand for phonation. The modified nasopharyngeal airway device is potentially very promising, but cases must be selected carefully to avoid compromising efficacy and safety. [ABSTRACT FROM AUTHOR]

Voice therapy often emphasizes vibratory sensations in the front part of the vocal tract during phonation to improve vocal efficiency. It remains unclear what laryngeal and vocal tract adjustments are elicited in speakers by this emphasis on oral vibratory sensations. Using a three-dimensional phonation model, this study aims to identify laryngeal and epilaryngeal adjustments that might produce maximal oral vibratory sensations during phonation, as quantified by the oral sound pressure level (SPL), and thus are likely to be elicited in voice therapy at different semi-occluded vocal tract configurations. Results show that maximum oral SPL occurs at intermediate vocal fold adduction configurations characterized by a trade-off between glottal gap and vocal fold vertical thickness. Epilaryngeal tube narrowing further increases the oral SPL in an open vocal tract, but has little effect on oral SPL in semi-occluded vocal tracts. Laryngeal and epilaryngeal configurations producing the maximum oral SPL generally have lower peak vocal fold contact pressure when producing a target output SPL. These favorable configurations are more easily identified in open vocal tracts than semi-occluded vocal tracts. However, semi-occlusion increases both the mean and dynamic oral pressure, which may familiarize speakers with oral vibratory sensations and facilitate adoption of favorable laryngeal configurations.

The aim of the study was to compare the acoustic characteristics of voice between Auditory Brainstem Implantees, Cochlear Implantees and normal hearing children. Voice parameters such as fundamental frequency, formant frequencies, perturbation measures, and harmonic to noise ratio were measured in a total of 30 children out of which 10 were Auditory Brainstem Implantees, 10 were Cochlear Implantees and 10 were normal hearing children. Parametric and nonparametric statistics were done to establish the nature of significance between the three groups. Overall deviancies were seen in the implanted group for all acoustic parameters. However abnormal deviations were seen in individuals with Auditory Brainstem Implants indicating the deficit in the feedback loop impacting the voice characteristics. The deviancy in feedback could attribute to the poor performance in ABI and CI. The CI performed comparatively better when compared to the ABI group indicating a slight feedback loop due to the type of Implant. However, there needs to be additional evidence supporting this and there is a need to carry out the same study using a larger sample size and a longitudinal design. [ABSTRACT FROM AUTHOR]

Gérard Diffloth (1937–2023) was a leading authority on Austroasiatic languages, with a wide range of linguistic interests ranging from historical reconstruction to expressives, and much more. He was a tireless fieldworker who firmly believed that research into the linguistic history of Austroasiatic need be grounded in long-term fieldwork with native speakers in their daily speech environment. In this paper we introduce an unpublished manuscript on the phonology of the Tri language spoken in Vilabouly District, Savannakhet Province in southern Laos. We frame this with a brief introduction to his work, with a tribute to his commitment to fieldwork and the principles he maintained throughout the many decades of working with speakers of Austroasiatic languages. [ABSTRACT FROM AUTHOR]

Within-speaker variability, which results from the plasticity of speech production, is an inherent feature of speaker comparison. This study examines targeted modifications of voice quality, both phonatory and articulatory, in Czech. Fifteen speakers were instructed to read a text in 15 different versions (e.g. palatalised voice, denasalised voice, breathy phonation, or a combination of open jaw and creaky voice). Acoustic analyses revealed that F3 is relatively stable across various voice quality settings, while harmonicity and spectral slope indicators are sensitive to the phonatory modifications. A perceptual test, administered online to 120 participants, showed that palatalised, pharyngealised, creaky, and pressed voice were regarded as most different from the speakers' habitual voices. Finally, automatic speaker recognition scores were very good with the targeted voice quality modifications, with LLR between 3 and 10. Pressed phonation turned out to have the greatest effect on all three types of analysis. [ABSTRACT FROM AUTHOR]

Investigations of neuromuscular control of voice production have primarily focused on the roles of muscle activation levels, posture, and stiffness at phonation onset. However, little work has been done investigating the stability of the phonation process in regards to spontaneous changes in vibratory mode of vocal fold oscillation as a function of neuromuscular activation. We evaluated 320 phonatory conditions representing combinations of superior and recurrent laryngeal nerve (SLN and RLN) activations in an in vivo canine model of phonation. At each combination of neuromuscular input, airflow was increased linearly to reach phonation onset and beyond from 300 to 1400 mL/s. High-speed video and acoustic data were recorded during phonation, and spectrograms and glottal-area-based parameters were calculated. Vibratory mode changes were detected based on sudden increases or drops of local fundamental frequency. Mode changes occurred only when SLNs were concurrently stimulated and were more frequent for higher, less asymmetric RLN stimulation. A slight increase in amplitude and cycle length perturbation usually preceded the changes in the vibratory mode. However, no inherent differences between signals with mode changes and signals without were found.

ObjectivesLaryngeal vibratory asymmetry occurring with paresis may result in a perceptually normal or abnormal voice. The present study aims to determine the relationships between the degree of vibratory asymmetry, acoustic measures, and perception of sound stimuli.Study designAnimal Model of Voice Production, Perceptual Analysis of Voice.MethodsIn an in vivo canine model of phonation, symmetric and asymmetric laryngeal vibration were obtained via graded unilateral recurrent laryngeal nerve (RLN) stimulation simulating near paralysis to full activation. Phonation was performed at various contralateral RLN and bilateral superior laryngeal nerve stimulation levels. Naïve listeners rated the perceptual quality of 182 unique phonatory samples using a visual sort-and-rate task. Cepstral peak prominence (CPP) was calculated for each phonatory condition. The relationships among vibratory symmetry, CPP, and perceptual ratings were evaluated.ResultsA significant relationship emerged between RLN stimulation and perceptual rating, such that sound samples from low RLN levels were preferred to those from high RLN levels. When symmetric vibration was achieved at mid-RLN stimulation, listeners preferred samples from symmetric vibration over those from asymmetric vibration. However, when symmetry was achieved at high RLN levels, a strained voice quality resulted that listeners dispreferred over asymmetric conditions at lower RLN levels. CPP did not have a linear relationship with perceptual ratings.ConclusionsLaryngeal vibratory asymmetry produces variable perceptual differences in phonatory sound quality. Though CPP has been correlated with dysphonia in previous research, its complex relationship with quality limits its usefulness as clinical marker of voice quality perception.Level of evidenceNA, basic science Laryngoscope, 131:2740-2746, 2021.

Prevalence estimates of Parkinson’s disease (PD)—the fastest-growing neurodegenerative disease—are generally underestimated due to issues surrounding diagnostic accuracy, symptomatic undiagnosed cases, suboptimal prodromal monitoring, and limited screening access. Remotely monitored wearable devices and sensors provide precise, objective, and frequent measures of motor and non-motor symptoms. Here, we used consumer-grade wearable device and sensor data from the WATCH-PD study to develop a PD screening tool aimed at eliminating the gap between patient symptoms and diagnosis. Early-stage PD patients (n = 82) and age-matched comparison participants (n = 50) completed a multidomain assessment battery during a one-year longitudinal multicenter study. Using disease- and behavior-relevant feature engineering and multivariate machine learning modeling of early-stage PD status, we developed a highly accurate (92.3%), sensitive (90.0%), and specific (100%) random forest classification model (AUC = 0.92) that performed well across environmental and platform contexts. These findings provide robust support for further exploration of consumer-grade wearable devices and sensors for global population-wide PD screening and surveillance.

Three laryngeal models were used to investigate the aerodynamic and elastic properties of vocal fold vibration: cadaveric human, excised canine, and synthetic silicone vocal folds. The aim was to compare the characteristics of these models to enhance our understanding of phonatory mechanisms. Flow and medial glottal wall geometry were acquired via particle image velocimetry. Elastic properties were assessed from force–displacement tests. Relatively, the human larynges had higher fundamental frequency values, while canine and synthetic models exhibited greater flow rates. Canine models demonstrated the highest divergence angles and vertical stiffness gradients followed by the human model, both displaying flow separation vortices during closing. Synthetic models, whose advantage is their accessibility and repeatability, displayed the lowest glottal divergence angles and total circulation values compared to tissue models with no flow separation vortices. The elasticity tests revealed that tissue models showed significant hysteresis and vertical stiffness gradients, unlike the synthetic models. These results underscore the importance of model selection based on specific research needs and highlight the potential of canine and synthetic models for controlled experimental studies in phonation.

This article provides a detailed examination of voice quality in word-final vowels in Spanish. The experimental task involved the pronunciation of words in two prosodic contexts by native Spanish speakers from diverse dialects. A total of 400 vowels (10 participants × 10 words × 2 contexts × 2 repetitions) were analyzed acoustically in Praat. Waveforms and spectrograms were inspected visually for voice, creak, breathy voice, and devoicing cues. In addition, the relative amplitude difference between the first two harmonics (H1–H2) was obtained via FFT spectra. The findings reveal that while creaky voice is pervasive, breathy voice is also common, and devoicing occurs in 11% of tokens. We identify multiple phonation types (up to three) within the same vowel, of which modal voice followed by breathy voice was the most common combination. While creaky voice was more frequent overall for males, modal voice tended to be more common in females. In addition, creaky voice was significantly more common at the end of higher prosodic constituents. The analysis of spectral tilt shows that H1–H2 clearly distinguishes breathy voice from modal voice in both males and females, while H1–H2 values consistently discriminate creaky and modal voice in male participants only.

Objective To determine correlations of alternation motor rate (AMR), sequential motor rate (SMR), and maximum phonation time (MPT) with the severity of dysphagia in subacute stroke patients. Methods This was a retrospective chart review study. Data of 171 subacute stroke patients were analyzed. Patient’s AMR, SMR, and MPT data were collected from their language evaluations. Video fluoroscopic swallowing study (VFSS) was done. Data of dysphagia scales including penetration-aspiration scale (PAS), American Speech-Language-Hearing Association National Outcomes Measurement System (ASHA-NOMS) scale, clinical dysphagia scale (CDS), and videofluoroscopic dysphagia scale (VDS) were obtained. AMR, SMR, and MPT were compared between a non-aspirator group and an aspirator group. Correlations of AMR, SMR, and MPT with dysphagia scales were analyzed. Results AMR ("ka"), SMR, and modified Rankin Scale were significant associated factors between non-aspirator group and aspirator group, while AMR ("pa"), AMR ("ta"), and MPT were not. AMR, SMR, and MPT showed significant correlations with PAS score, ASHA-NOMS scale, CDS, VDS oral, and VDS pharyngeal scores. The cut-off value for distinguishing non-aspirator group and aspiration group was 18.5 for AMR ("ka") (sensitivity of 74.4%, specificity of 70.8%) and 7.5 for SMR (sensitivity of 89.9%, specificity of 61.0%). AMR and SMR were significantly lower in before-swallow aspiration group. Conclusion Articulatory diadochokinetic tasks that can be easily performed at the bedside would be particularly helpful in determining the oral feeding possibility of subacute stroke patients who cannot undergo VFSS, which is the gold standard for dysphagia assessment.

Introduction: Hypophonia is a common feature of Parkinson's disease (PD); however, the contribution of motor cortical activity to reduced phonatory scaling in PD is still not clear. Methods: In this study, we employed a sustained vowel production task during functional magnetic resonance imaging to compare brain activity between individuals with PD and hypophonia and an older healthy control (OHC) group. Results: When comparing vowel production versus rest, the PD group showed fewer regions with significant BOLD activity compared to OHCs. Within the motor cortices, both OHC and PD groups showed bilateral activation of the laryngeal/phonatory area (LPA) of the primary motor cortex as well as activation of the supplementary motor area. The OHC group also recruited additional activity in the bilateral trunk motor area and right dorsal premotor cortex (PMd). A voxel-wise comparison of PD and HC groups showed that activity in right PMd was significantly lower in the PD group compared to OHC (p < 0.001, uncorrected). Right PMd activity was positively correlated with maximum phonation time in the PD group and negatively correlated with perceptual severity ratings of loudness and pitch. Discussion: Our findings suggest that hypoactivation of PMd may be associated with abnormal phonatory control in PD. [ABSTRACT FROM AUTHOR]

Dysphagia after esophagectomy is a major risk factor for aspiration pneumonia, thus preoperative assessment of swallowing function is important. The maximum phonation time (MPT) is a simple indicator of phonatory function and also correlates with muscle strength associated with swallowing. This study aimed to determine whether preoperative MPT can predict postoperative aspiration pneumonia. The study included 409 consecutive patients who underwent esophagectomy for esophageal cancer between 2017 and 2021. Pneumonia detected by routine computed tomography on postoperative days 5–6 was defined as early-onset pneumonia, and pneumonia that developed later (most often aspiration pneumonia) was defined as late-onset pneumonia. The correlation between late-onset pneumonia and preoperative MPT was investigated. Patients were classified into short MPT (<15 seconds for males and <10 seconds for females, n  = 156) and normal MPT groups (≥15 seconds for males and ≥10 seconds for females, n  = 253). The short MPT group was significantly older, had a lower serum albumin level and vital capacity, and had a significantly higher incidence of late-onset pneumonia (18.6 vs. 6.7%, P  < 0.001). Multivariate analysis showed that short MPT was an independent risk factor for late-onset pneumonia (odds ratio: 2.26, P  = 0.026). The incidence of late-onset pneumonia was significantly higher in the short MPT group (15.6 vs. 4.7%, P  = 0.004), even after propensity score matching adjusted for clinical characteristics. MPT is a useful predictor for late-onset pneumonia after esophagectomy. [ABSTRACT FROM AUTHOR]

Nonlinear phenomena (NLP) in animal vocalizations arise from irregularities in the oscillation of the vocal folds. Various non-mutually exclusive hypotheses have been put forward to explain the occurrence of NLP, from adaptive to physiological ones. Non-human primates often display NLP in their vocalizations, yet the communicative role of these features, if any, is still unclear. We here investigate the occurrence of NLP in the song of a singing primate, the indri (Indri indri), testing for the effect of sex, age, season, and duration of the vocal display on their emission. Our results show that NLP occurrence in indri depends on phonation, i.e., the cumulative duration of all the units emitted by an individual, and that NLP have higher probability to be emitted in the later stages of the song, probably due to the fatigue indris may experience while singing. Furthermore, NLP happen earlier in the vocal display of adult females than in that of the adult males, and this is probably due to the fact that fatigue occurs earlier in the former because of a greater contribution within the song. Our findings suggest, therefore, that indris may be subjected to physiological constraints during the singing process which may impair the production of harmonic sounds. However, indris may still benefit from emitting NLP by strengthening the loudness of their signals for better advertising their presence to the neighboring conspecific groups. [ABSTRACT FROM AUTHOR]

Purpose Many children with cerebral palsy (CP) are described as having altered vocal quality. The current study utilizes psychoacoustic measures, namely, low-amplitude (H1*-H2*) and high-amplitude (H1*-A2*) spectral tilt and cepstral peak prominence (CPP), to identify the vocal fold articulation characteristics in this population. Method Eight children with CP and eight typically developing (TD) peers produced vowel singletons [i, ɑ, u] and a story retell task with the same vowels in the words "beets, Bobby, boots." H1*-H2*, H1*-A2*, and CPP were extracted from each vowel. Results were analyzed with mixed linear models to identify the effect of Group (CP, TD), Task (vowel singleton, story retell), and Vowel [i, ɑ, u] on the dependent variables. Results Children with CP have lower spectral tilt values (H1*-H2* and H1*-A2*) and lower CPP values than their TD peers. For both groups, vowel singletons were associated with lower CPP values as compared to story retell. Finally, the vowel [ɑ] was associated with higher spectral tilt and higher CPP values as compared to [i, u]. Conclusions Children with CP have more constricted and creaky vocal quality due to lower spectral tilt and greater noise. Unlike adults, children demonstrate poorer vocal fold articulation when producing vowel singletons as compared to story retell. Finally, low vowels like [ɑ] seem to be produced with less constriction and noise as compared to high vowels.

The human vocal fold (VF) oscillates in multiple vectors and consists of distinct layers with varying viscoelastic properties that contribute to the mucosal wave. Office-based and operative laryngeal endoscopy are limited to diagnostic evaluation of the VF epithelial surface only and are restricted to axial-plane characterization of the horizontal mucosal wave. As such, understanding of the biomechanics of human VF motion remains limited. Optical coherence tomography (OCT) is a micrometer-resolution, high-speed endoscopic imaging modality which acquires cross-sectional images of tissue. Our study aimed to leverage OCT technology and develop quantitative methods for analyzing the anatomy and kinematics of in vivo VF motion in the coronal plane. A custom handheld laryngeal stage was used to capture OCT images with 800 A-lines at 250 Hz. Automated image postprocessing and analytical methods were developed. Novel kinematic analysis of in vivo, long-range OCT imaging of the vibrating VF in awake human subjects is reported. Cross-sectional, coronal-plane panoramic videos of the larynx during phonation are presented with three-dimensional videokymographic and space-time velocity analysis of VF motion. Long-range OCT with automated computational methods allows for cross-sectional dynamic laryngeal imaging and has the potential to broaden our understanding of human VF biomechanics and sound production.

Objectives/hypothesisArytenoid adduction (AA) is performed to treat unilateral vocal fold paralysis with a large posterior glottal gap. However, the voice effects of AA suture position remain unclear. This study aimed to evaluate voice production and quality as a function of AA suture position on the thyroid ala in a neuromuscularly intact in vivo larynx.Study designAnimal model.MethodsUnilateral recurrent laryngeal nerve and vagal paralysis were modeled in two canines. AA suture position was varied across five equidistant positions on the anterior inferior thyroid ala, from a paramedian position anteriorly to the oblique line posteriorly. Phonation was performed over 8 × 8 graded level combinations of recurrent and superior laryngeal nerve stimulation per suture position. The primary outcome was percent successful phonatory conditions. Secondary outcomes included fundamental frequency (F0), phonation onset pressure (PTP), cepstral peak prominence (CPP), and laryngeal posture.ResultsAnterior suture positions resulted in a greater percentage of successful phonatory conditions compared to posterior sutures. Suture position 2, located at the anterior inferior thyroid ala, resulted in the highest percentage of successful phonatory conditions, lowest PTP, and lower muscle activation levels to achieve higher CPP. Posterior sutures resulted in wider glottal gap and more effective F0 and vocal fold strain increase with cricothyroid muscle contraction, but with fewer successful phonatory conditions and higher PTP. Trends were consistent across both paralysis types.ConclusionsAA suture placed in the anterior inferior thyroid ala resulted in the best acoustic, aerodynamic, and voice quality outcomes. This study provides scientific evidence for maintaining current clinical practice.Level of evidenceNA Laryngoscope, 131:846-852, 2021.

In the clinic, many diagnostic and therapeutic procedures focus on the oscillation patterns of the vocal folds (VF). Dynamic characteristics of the VFs, such as symmetry, periodicity, and full glottal closure, are considered essential features for healthy phonation. However, the relevance of these individual factors in the complex interaction between the airflow, laryngeal structures, and the resulting acoustics has not yet been quantified. Sustained phonation was induced in nine excised porcine larynges without vocal tract (supraglottal structures had been removed above the ventricular folds). The multimodal setup was designed to simultaneously control and monitor key aspects of phonation in the three essential parts of the larynx. More specifically, measurements will comprise (1) the subglottal pressure signal, (2) high-speed recordings in the glottal plane, and (3) the acoustic signal in the supraglottal region. The automated setup regulates glottal airflow, asymmetric arytenoid adduction, and the pre-phonatory glottal gap. Statistical analysis revealed a beneficial influence of VF periodicity and glottal closure on the signal quality of the subglottal pressure and the supraglottal acoustics, whereas VF symmetry only had a negligible influence. Strong correlations were found between the subglottal and supraglottal signal quality, with significant improvement of the acoustic quality for high levels of periodicity and glottal closure.

High-resolution manometry (HRM) is a motility diagnostic system that measures intraluminal pressure of the gastrointestinal tract using a series of closely spaced pressure sensors. The topographic plot generated by HRM software makes it possible to visualize phonation pressures at the pharynx, UES, and body of the esophagus in real time, indicating pressure intensity by color, which permits easy data interpretation. It has been largely used for swallowing study and dysphagia diagnosis. Due to the proximity of the pharyngoesophageal and laryngeal structures, this technology instigated voice researchers. Despite the few studies published so far, high-resolution manometry has yet proven to be an extremely useful tool in obtaining entire pharyngoesophageal segment pressure measurements during phonation. It also allows natural voice production not interfering with the mouth area. HRM data already brought light to subglottic pressure, vertical laryngeal excursion, cricopharyngeal muscle activation, air flow, muscle tension associated with vocalization and pressure variations associated with different phonatory stimuli.

Purpose: This scoping review aims to synthesize all of the currently available information on how xerostomia correlates with vocal function and the mechanisms that underpin it. Methods: Our scoping review used PubMed, Scopus, Embase, and Web of Science databases to review articles published between January 1999 and July 2022 in accordance with the PRISMA-ScR guidelines. In addition to the academic databases, we also conducted a manual search of Google Scholar. Further investigation was conducted on studies that examined the relationship between xerostomia and vocal function. Results: Of the 682 initially identified articles, 21 met our inclusion criteria. Among the included studies, two articles (n = 2) revealed the mechanistic relationship between xerostomia and vocal function. Most studies (n = 12) focused on xerostomia secondary to other underlying conditions or treatments, among which radiotherapy and Sjögren's syndrome were commonly investigated. Seven studies (n = 7) provided details about common vocal parameters measured in studies of xerostomia and the voice. Conclusion: The literature currently lacks publications regarding the relationship between xerostomia and vocal function. Most of the studies included in this review were about xerostomia secondary to other conditions or medical treatments. Therefore, the impacts on the voice that were observed were very multifaceted and the role of xerostomia alone in phonation could not be ascertained. Nevertheless, it is clear that dryness in the mouth plays some role in vocal function and further research should focus on clarifying and finding the underlying mechanism behind this relationship by incorporating high-speed imaging and cepstral peak prominence analyses. [ABSTRACT FROM AUTHOR]

Background and Objectives: Learning to speak properly requires a fully formed brain, good eyesight, and a functioning auditory system. Defective phonation is the outcome of a failure in the development of any of the systems or components involved in speech production. Dentures with strong phonetic skills can be fabricated with the help of a dentist who has a firm grasp of speech production and phonetic characteristics. Every dentist strives to perfect their craft by perfecting the balance between the technical, cosmetic, and acoustic aspects of dentistry, or "phonetics". The ideal prosthesis for a patient is one that not only sounds good but also functions well mechanically and aesthetically. Words are spoken by using articulators that alter their size and form. Conclusions: Therefore, a prosthesis should be made in such a way that it does not interfere with the ability to communicate. As a result, a prosthodontist has to have a solid grasp of how speech is made and the numerous parts that go into it. [ABSTRACT FROM AUTHOR]

This study examines articulatory and acoustic data in order to investigate the non-coalescence of /h/ in South Jeolla. Seoul Korean speakers produce /pap/ "rice" followed by /hana/ "one" as [pa. p ha.na] with the coalescence of /p/ and /h/; this is called an aspiration merger. In South Jeolla Korean, this merger may be blocked, as in cases where speakers produce /pap+hana/ as [pa. b a.na]. Electroglottographic (EGG) data indicate the existence of two groups of South Jeolla speakers: one that merges the plosive and /h/ (the merger group), and the other with the canonical South Jeolla Korean pronunciation that does not merge the two consonants (the non-merger group). The production of non-coalesced lenis stops in the non-merger group is phonetically comparable with an underlying lenis stop produced by both of the groups. However, in the non-merger group, the open quotient (OQ) of a vowel following a non-coalesced lenis stop is higher (breathier) than that of an underlying lenis stop. Spectral tilt results display a similarly increased breathiness when the vowel follows a non-coalesced lenis stop. As for the non-merger group of South Jeolla, we argue that speakers display incomplete neutralization such that the non-merger group produces two types of voiced lenis stops differing in the phonation of the following vowel. These findings suggest that previous phonological analyses that posit the /h/-deletion in the non-merger group of South Jeolla Korean need to be revisited. [ABSTRACT FROM AUTHOR]

This paper presents an alternative description of plain, and complex click consonants and their relationship to non-click consonants in Khoesan languages. Our research was based on data gathered from key informants and focus groups in Namibia's Karas, Hardap, and Kunene regions, as well as secondary sources. Our findings challenge the common belief that plain clicks in Khoekhoegowab are glottalized, suggesting instead that the glottalization is a result of the accompanying vowel. We also use articulatory and auditory phonetics to question the concept of "complexity" in click complexes and demonstrate that these click consonants serve the same morphophonological function as consonants in non-click languages. In conclusion, we argue that plain and complex clicks should be viewed as part of the same continuum as non-click consonants. [ABSTRACT FROM AUTHOR]

The goal of this study is to identify laryngeal strategies that minimize vocal fold contact pressure while producing a target sound pressure level (SPL) using a three-dimensional voice production model. The results show that while the subglottal pressure and transverse stiffness can be manipulated to reduce the peak contact pressure, such manipulations also reduce the SPL, and are thus less effective in reducing contact pressure in voice tasks targeting a specific SPL level. In contrast, changes in the initial glottal angle and vocal fold vertical thickness that reduce the contact pressure also increase the SPL. Thus, in voice tasks targeting a specific SPL, such changes in the initial glottal angle and vertical thickness also lower the subglottal pressure, which further reduces the peak contact pressure. Overall the results show that for voice tasks with a target SPL level, vocal fold contact pressure can be significantly reduced by adopting a barely abducted glottal configuration or reducing the vocal fold vertical thickness. Aerodynamic measures are effective in identifying voice production with large initial glottal angles, but by themselves alone are not useful in differentiating hyperadducted vocal folds from barely abducted vocal folds, which may be better differentiated by closed quotient and voice type measures.