Voice Production Research Articles

From phenotype to phonotype: a comprehensive description of voice features of Cri du chat syndrome.

Genetic syndromes have been studied by extensive research allowing a better definition of their clinical manifestations, natural history, and etiopathogenetic mechanisms. Nevertheless, some relevant, but still unexplored aspects of these multisystemic conditions need to be clarified. One of these aspects is the characterization of the vocal production, especially in some genetic syndromes in which the distinctive voice is the hallmark of the syndrome (e.g., Cri du chat syndrome, CdCS). The aim of this study is to provide a detailed description of phonotype of patients affected by CdCS. We prospectively recorded and analysed acoustical features of three corner vowels [a], [i], and [u] and number listing from 1 to 10 of 29 patients with molecularly confirmed CdCS (age range 4-21 years; mean 11 ± 6; median 10 years). For perceptual analysis, the GIRBAS scale was completed. The acoustical analysis was performed through BioVoice software. When stratified by age and gender, in the older men subgroup the grade, roughness, and asthenia mean values are the highest for each vowel, when compared with values of the same parameters obtained in the other subgroups. Statistical analysis highlighted 26 significant differences: 38% (10) concern the sustained phonation of /a/, 27% (7) are related to /i/ whereas 19% (5) to /u/. Ratio1, Ratio2, VSA, and FCR were also significant. Conclusion: The voice production not only conveys linguistic and paralinguistic information but also can give information regarding the speaker's biological and clinical characteristics.

Methods of Voice Restoration following Laryngectomy

In Germany, approximately 950-1200 laryngectomies are performed annually due to extensive hypopharyngeal and laryngeal carcinomas. The removal of the larynx results in significant life changing functional losses, particularly in voice production and communication, resulting in psychological issues and social withdrawal. Rehabilitation requires a multidisciplinary team focusing on restoring communication skills. Methods include pseudowhispering, esophageal speech, external mechanical and electromechanical aids, and tracheoesophageal speech prostheses. Pseudowhispering uses air from the mouth and pharynx, while esophageal speech requires controlled release of esophageal air to produce sound. External aids include devices like the Electrolarynx. Tracheoesophageal speech prostheses, the current gold standard, offer superior phonation time and clarity but require frequent visits to the healthcare system to address complications due to the limited lifespan of the prosthesis. Despite high success rates with transoesophageal prostheses, some patients may face significant challenges. In conclusion, voice rehabilitation post-laryngectomy is crucial for social reintegration. Comprehensive patient education on the benefits and challenges of different methods is essential for making an informed decision tailored to their lifestyle.

Modeling voice production and self-perception in noise: Understanding the Lombard effect in non-phonotraumatic vocal hyperfunctiona).

The sensorimotor adaptation process is crucial for maintaining oral communication. Recent studies have shown that individuals with non-phonotraumatic vocal hyperfunction (NPVH) experience difficulties in sensorimotor adaptation when speaking in noise (known as the Lombard effect). However, the role of auditory and somatosensory feedback in the dynamics of adaptation to speaking in noise is still unclear. In this study, the use of a simple three-parameter mathematical model, known as SimpleDIVA model, was extended to explore the adaptation dynamics of speaking in noise among a group of participants with typical voices and NPVH. All participants were asked to utter a series of syllables under three conditions: baseline (quiet environment), Lombard (speech-shaped noise at 80 dB), and recovery (quiet environment after 5 min of rest). The results indicate that participants with NPVH did not return to baseline after exposure to speaking under noise. The SimpleDIVA model analysis reveals a diminished feedforward learning rate and reduced somatosensory feedback gain in participants with NPVH in comparison to participants with typical voices. This suggests that participants with NPVH may be using less somatosensory information when speaking in noise and may require more time to update the feedforward commands during and after speaking in noise.

Changes in Voice Quality after a Pure Tone Stimulation (PTS) Program

Introduction. Auditory feedback allows individuals to monitor their vocal characteristics and adjust to maintain optimal voice quality. One type of auditory stimulation for conversational voice training/therapy is pure tone stimulation. This technique presents binaural auditory stimuli consisting of pure tones separated by half-step intervals to modify the fundamental frequency of the speaking voice and expand the vocal range. Objectives. This study aimed to characterize detectable changes in voice production following the application of pure tone stimulation (PTS) among speakers with and without voice disorders. Methods. Data from thirty-nine participants (28 individuals with voice disorders and 11 individuals with normal voices) were analyzed for this study. All participants engaged in binaural PTS exercises. Participants recorded a sustained vowel /a/ before and after the PTS exercises. Multiple acoustic voice parameters were extracted from the sustained vowel samples (fundamental frequency, pitch strength, harmonics-to-noise ratio, and smoothed cepstral peak prominence). Additionally, a visual analogue scale (VAS) interpretation of narrowband (NB) spectrograms was conducted to assess voice quality. Results. Statistically significant increases in fundamental frequency were found after the PTS exercises, except for males in the normal voices group. Pitch strength increased after the PTS, regardless of gender. Participants also demonstrated an increase in the harmonics-to-noise ratio. VAS ratings of NB spectrograms indicated improvement in voice quality following the program. Conclusions. Voice changes after performing PTS suggest voice quality improvement, as measured by acoustic analysis of vowel production and qualitative assessment of NB spectrograms among participants with and without voice disorders.

Coupled processes of tissue oxygenation and fluid flow in biphasic vocal folds

Fluid-structure interaction (FSI) between the glottal airflow and the poroelastic tissue of the vocal folds (VFs) causes the VFs to vibrate, resulting in voice production. Prior experimental studies have reported that biological transport processes within the VF tissue play a crucial role in disease initiation and localized lesions. Particularly, it has been observed that physiological conditions during phonation influence the interstitial flow within the tissue and the associated oxygen partial pressure, which corresponds with dysfunctions such as intermittent hypoxia. The goal of this research is to develop a multiphysics computational methodology that investigates oxygen transport characteristics within the VFs. By considering transient glottal airflow and a biphasic description for the tissue, this coupled framework combines an FSI model with a mass transport model to quantify key features contributing to VF oxygenation. The Navier-Stokes equations represent the aerodynamics in the larynx, while linear elasticity for tissue dynamics is considered. Additionally, oxygen transport is simulated using the advection-diffusion-reaction equation, and the interstitial flow is solved via the Brinkman equation. Physiological parameters such as oxygen metabolic consumption, subglottal lung pressure, and tissue permeability coefficient are varied; and their contribution to oxygen supply as well as to the liquid dynamics within the VF are quantified. It is found that filtration velocity is directly proportional to subglottal pressure and tissue permeability. Oxygen flow is also found to be inversely related to reaction rate, directly related to permeability, and not noticeably affected by subglottal pressure. The findings provide insight into the VF oxygenation pathways and the potential link with some pathological states such as hypoxia and localized lesions.

Influence of Raoul Husson’s neurochronaxic theory for the development of research on the physiological mechanisms of voice production in the Soviet Union (1950–1970s)

The influence of the neurochronaxic theory of phonation of the French physiologist Raoul Husson (1901–1967) on the development of research on voice formation in the Soviet Union, mainly in the 1950–1970s, is discussed. Husson contrasted the neurochronaxic theory with the traditional myoelastic theory of voice formation. The myoelastic theory considers the vocal folds as a self-oscillatory system. Vibrations are caused by the energy of the air flow. According to Husson’s concept, vibrations of the vocal cords do not depend on subglottic pressure. The frequency of vibration of the vocal cords corresponds to the frequency of impulses arriving along the recurrent nerve. To explain the high frequency of vibration of the vocal cords, Husson used Wever’s “Volley Principle”. According to this principle, the activity of each subsequent nerve fiber occurs during the refractory phase of the previous fiber. The responses of all nerve fibers are summed up into a common high-frequency oscillation. In 1950–1970s, Soviet physiologists took an active part in testing the new concept proposed by Husson. They came to the conclusion that both mechanisms, myoelastic and neurochronaxic, are involved in the functioning of the vocal apparatus. But the recurrent nerve does not directly control the vibrations of the vocal cords, but indirectly. Žhinkin called this control system the “code principle,” when a command is sent to the vocal cords to change their physical characteristics, changing the properties of the self-oscillating system.

Correlation between voice intensity and swallowing function in subjects with Parkinson's disease.

People with Parkinson's Disease (PD) experience reduced voice intensity and dysphagia. Organs related to voice production and swallowing are structurally and neurologically intertwined. Thus, instrumental voice assessment may be useful in identifying voice impairments that can show swallowing disorders. Timely assessment of swallowing disorders may prevent the occurrence of malnutrition, dehydration, pneumonia, and death. The aim of this study was to investigate the relationship between voice intensity and swallowing function in PD. 30 participants with PD were recruited. Motor disability was evaluated by the Unified Parkinson's Disease Rating Scale part III; voice intensity was assessed by PRAAT software during sustained /a/ and 1min of monologue. The Penetration Aspiration Scale, the Dysphagia Outcome Severity Scale, and the Videofluoroscopic Dysphagia Scale were used to assess swallowing during videofluoroscopy. Spearman correlation coefficients, logistic, and linear models were used to analyze data. Voice intensity correlated with swallowing: as voice intensity decreased, swallowing function deteriorated (Spearman coefficients from -0.42 to -0.72 across scales), and this holds even when adjusted for MDS-UPDRS motor scores. Swallowing impairment is 56 times more likely (p<0.01) when the voice intensity is below the normal cut-off score (60 dB) with a positive predictive value of 93%. Reduction in voice intensity is indicative of a higher risk of swallowing dysfunction. Thus, an instrumental voice analysis seems to be a non-invasive, lowcost, easy-to-use tool to identify people with PD in need of an assessment to allow for timely swallowing management and reduction of complications caused by dysphagia.

Optimizing a small room for critical listening with Treble

This work presents a detailed validation of new software Treble launched in 2023 that hybridizes the discontinuous Galerkin method and pressure-based geometrical acoustics methods. We investigated a small studio for voice productions both through physical measurements and treble's room acoustic simulations. By employing a dense measurement grid with a spacing of 25 cm at the ear level, a comprehensive validation of the room acoustic simulation was conducted in terms of room impulse responses, transfer functions, ISO 3382 acoustic parameters and sound pressure level distribution. Treble's simulation successfully predict the room modes, ISO 3382 acoustic parameters as well as the sound level distribution. The study demonstrates the impact of speaker positions, particularly regarding their interaction with boundary surfaces and how this can be planned with the simulation.

Listen to yourself! Prioritization of self-associated and own voice cues.

Self-cues such as one's own name or face attract attention, reflecting a bias for stimuli connected to self to be prioritized in cognition. Recent evidence suggests that even external voices can elicit this self-prioritization effect; in a voice-label matching task, external voices assigned to the Self-identity label 'you' elicited faster responses than those assigned to 'friend' or 'stranger' (Payne etal., Br. J. Psychology, 112, 585-610). However, it is not clear whether external voices assigned to Self are prioritized over participants' own voices. We explore this issue in two experiments. In Exp 1 (N = 35), a voice-label matching task comprising three external voices confirmed that reaction time and accuracy are improved when an external voice cue is assigned to Self rather than Friend or Stranger. In Exp 2 (N = 90), one of the voice cues was replaced with a recording of the participant's own voice. Reaction time and accuracy showed a consistent advantage for the participant's own-voice, even when it was assigned to the 'friend' or 'stranger' identity. These findings show that external voices can elicit self-prioritization effects if associated with Self, but they are not prioritized above individuals' own voices. This has implications for external voice production technology, suggesting own-voice imitation may be beneficial.

Zygosity Effects on Human Voice: Fundamental Frequency Analysis of Brazilian Twins' Speech.

Voice production can be influenced by interindividual variations related to genetic, physiological, behavioral, and several environmental factors. Here we examined the effect of zygosity on speaking fundamental frequency (F0) statistical descriptors. Our aims were: (1) to determine whether the genetic similarity between monozygotic (MZ) and dizygotic (DZ) twins affects F0 characteristics, and (2) to quantify the contribution of genetic factors to these characteristics. The study involved 79 same-sex twin pairs of Brazilian Portuguese speakers, comprising 65 MZ and 14 DZ twins, aged 18 to 66 years (31.7 ± 11.6 years), with 21 male and 58 female pairs. Participants were recorded while uttering a greeting phrase and the Brazilian Portuguese version of the 'Happy Birthday to You' song. Speech segments were analyzed using Praat free software, and F0 measures were automatically extracted in both Hertz and semitone scales. Statistical descriptors, including centrality, dispersion, and extreme values of F0 were examined, and the ACE model (i.e., total genetic effects, A; shared environmental influences, C; and nonshared environmental influences, E) was employed to estimate the additive effect;ts of monozygosity. As anticipated, we observed a zygosity effect on several F0 parameters, with more similarity between MZ twins compared to DZ twins. We discuss the genetic influences on F0 parameters and the absence of a monozygosity effect in two of them. Additionally, we briefly address potential biases associated with the selected measurement scale for statistical modeling. Finally, we explore the influence of genetic factors on F0 patterns, as well as environmental, life history and linguistic factors, particularly concerning F0 variation in speech.

Comparison of Vocal Amplitude and Contact Speed according to SOVTE Type

Objectives: Observation of vocal fold vibration during semi-occluded vocal tract exercises (SOVTE) can help in understanding voice production due to semi-occlusion. This study aimed to investigate the differences in vocal fold vibration characteristics among various types of SOVTE. This study may provide valuable evidence to support more specific and effective methods in applying SOVTE to voice therapy. Methods: A total of 10 healthy young adults (5 males, 5 females) with a mean age of 24.28±4.54 years participated in the study. None of the participants had any voice-related diseases or were smokers. The participants performed various types of SOVTE including humming, voiced bilabial fricative, straw phonation, and water-resistance straw phonation. The authors measured the amplitude and contact speed of vocal fold using a vibration simulator and digital kymography (DKG). Results: The results showed that vocal fold amplitude was not significantly different among types of SOVTE, but there were significant differences in vocal fold contact speed (p=.046). In multiple comparisons, vocal fold contact speed was significantly faster in humming (p=.031) and water-resistance straw phonation (p=.018) compared to straw phonation. Conclusion: The difference in vocal fold contact speed indicates that the vocal fold vibration during SOVTE is affected by the shape of the vocal tract. The use of humming and water-resistance straw phonation can be an effective approach to improve voice quality by increasing vocal fold contact speed, which is a key factor in determining overall voice quality. These two methods can be useful in voice therapy after laryngeal microsurgery. In the field, conducting trial therapy rather than applying voice therapy according to the hierarchy of SOVTE may lead to successful results.

Large vocal polyp causing dyspnea to young patient

The vocal cords are primarily responsible for voice production and the risk factor for non-neoplastic vocal fold lesions is usually multifactorial, laryngeal trauma (endotracheal intubation), hypothyroidism, cigarette smoking, alcohol abuse, gastroesophageal reflux (GERD) and also including phonotrauma etc. we report a 30-year-old female presented with the complaint of dyspnea and hoarseness of voice. endoscopic examination showing, the very large vocal cord polyp was seen to be arising from the left vocal cord, partially blocking the glottic chink, with minimal residual airway. ML Scopy excision of the polyp was done and size was approximately 1.5 cm.

Application of psychodynamic model in the assessment and management of psychogenic voice disorder: a case report

The psychological state is considered to contribute to the overall well-being of an individual. Disequilibrium due to psychological reasons such as anxiety, stress, depression, or other psychological conditions may affect voice production entirely or partially, significantly affecting the person’s occupational, social, and emotional well-being. The present study discusses a sudden onset of aphonia in a 37-year-old female without an underlying physiological illness. The study illustrates the importance of interpreting the voice problem in the patient considering the influence of the individual's psychological, physiological, physical, emotional, and social health by applying the psychodynamic model.

Investigating the effectiveness of input-based techniques on the acquisition of English passive: A comparative study of explicit instruction and input-based techniques

This study investigates the efficacy of various grammar instruction techniques, namely focus-on-form (FonF) and focus-on-forms (FonFs), on the acquisition and production of the English passive voice. A quasi-experimental pre-test and post-test design was employed across four treatment groups without a control group, involving 62 Turkish learners of English, enrolled in preparatory classes at a public university in Turkey, with a B1 (intermediate) proficiency level. The study assessed the effectiveness of input flood (IF), input flood coupled with textual enhancement (IF + TE), input flood with explicit grammar teaching (IF + EGT), and rule-based instruction (RBI). Authentic texts on global warming and climate change were used as materials, with passive sentences underlined for the IF + TE group and explicit grammar explanations provided to the IF + EGT group. Findings point to a clear superiority of RBI in the learners’ grammatical acquisition and production, supporting the idea that explicit instruction, followed by controlled practice, significantly enhances learning outcomes. Contrary to RBI's success, the IF only approach did not yield a substantial impact, questioning the effectiveness of implicit teaching methods for complex grammatical structures. The study also examined the relationship between explicit knowledge and communicative practice, finding that explicit instruction is critical even within communicative frameworks. These outcomes align with the Noticing Hypothesis, emphasizing that conscious recognition of grammatical forms is necessary for effective language acquisition. The study contributes to the ongoing debate on the efficacy of explicit grammar instruction versus implicit learning, suggesting that a combination of instruction focusing on form within a communicative context can be beneficial for EFL learners.

Anchoring voices: The news anchor’s voice in China from television to AI

This paper takes the recent introduction of AI-powered television news anchors in China as an invitation to explore the technologies and techniques that have long been used in the anchor’s voice production. Analyzing Chinese Broadcasting Science, the first pedagogical standards for broadcasters across mainland China, published in 1993, this paper demonstrates how the perception of the anchor’s voice as something that can be measured, manipulated, and programmed has predated the AI industry. We examine guidelines, diagrams, and figures used to instruct news anchor wannabes on training their physiological voicing “engine,” tracing the continuities between this model of television anchoring and AI-generated news anchors. We propose technovocality as a conceptual framework for considering the various social, political, and ethical questions arising from the intersections between voices and media, past and present and Western and non-Western cultural contexts.

HEAR set: A ligHtwEight acoustic paRameters set to assess mental health from voice analysis

BackgroundVoice analysis has significant potential in aiding healthcare professionals with detecting, diagnosing, and personalising treatment. It represents an objective and non-intrusive tool for supporting the detection and monitoring of specific pathologies. By calculating various acoustic features, voice analysis extracts valuable information to assess voice quality. The choice of these parameters is crucial for an accurate assessment. MethodIn this paper, we propose a lightweight acoustic parameter set, named HEAR, able to evaluate voice quality to assess mental health. In detail, this consists of jitter, spectral centroid, Mel-frequency cepstral coefficients, and their derivates. The choice of parameters for the proposed set was influenced by the explainable significance of each acoustic parameter in the voice production process. ResultsThe reliability of the proposed acoustic set to detect the early symptoms of mental disorders was evaluated in an experimental phase. Voices of subjects suffering from different mental pathologies, selected from available databases, were analysed. The performance obtained from the HEAR features was compared with that obtained by analysing features selected from toolkits widely used in the literature, as with those obtained using learned procedures. The best performance in terms of MAE and RMSE was achieved for the detection of depression (5.32 and 6.24 respectively). For the detection of psychogenic dysphonia and anxiety, the highest accuracy rates were about 75 % and 97 %, respectively. ConclusionsThe comparative evaluation was carried out to assess the performance of the proposed approach, demonstrating a reliable capability to highlight affective physiological alterations of voice quality due to the considered mental disorders.

Coactivation of the Laryngeal Muscles in Pigs Without External Neural Control Indicates Existence of an Intrinsic Neuronal Network

Electrophysiological studies of the larynx expose the mechanisms by which voice production is controlled. Previous studies have revealed certain phenomena during laryngeal oscillations that suggest a complex control mechanism.Starting from the principle of agonist-antagonist muscular pairing, the aim of this study was to gain a deeper insight into the function of the cricothyroid and thyroarytenoid muscles, both central to voice production.Electromyographic recordings were used to determine the response of the two muscles to different stimulation situations in an ex-vivo animal model of the denervated larynx of pigs (n=26).Using a set of different experiments, it was shown that when one muscle (cricothyroid or thyroarytenoid muscle) was electrically stimulated, a response was observed in the other muscle, which in the otherwise denervated larynx was caused only by the applied stimulation and exhibited the characteristics of compound action potentials. This response was reproducible in all larynxes examined and was present bidirectionally. No response was registered in the absence of stimulation.Results show the existence of coactivation of the cricothyroid and thyroarytenoid muscles in the absence of external innervation hinting at the presence of a localized neuronal network of the larynx that has not been described previously. Further morphological investigation is needed to determine the presence of this internal laryngeal neuronal network.

Tracking age-related changes in voice and speech production with Landmark-based analysis of speech.

Voice and speech production change with age, which can lead to potential communication challenges. This study explored the use of Landmark-based analysis of speech (LMBAS), a knowledge-based speech analysis algorithm based on Stevens' Landmark Theory, to describe age-related changes in adult speakers. The speech samples analyzed were sourced from the University of Florida Aging Voice Database, which included recordings of 16 sentences from the Speech Perception in Noise test of Bilger, Rzcezkowski, Nuetzel, and Rabinowitz [J. Acoust. Soc. Am. 65, S98-S98 (1979)] and Bilger, Nuetzel, Rabinowitz, and Rzeczkowski [J. Speech. Lang. Hear. Res. 27, 32-84 (1984)]. These sentences were read in quiet environments by 50 young, 50 middle-aged, and 50 older American English speakers, with an equal distribution of sexes. Acoustic landmarks, specifically, glottal, bursts, and syllabicity landmarks, were extracted using SpeechMark®, MATLAB Toolbox version 1.1.2. The results showed significant age effect on glottal and burst landmarks. Furthermore, the sex effect was significant for burst and syllabicity landmarks. While the results of LMBAS suggest its potential in detecting age-related changes in speech, increase in syllabicity landmarks with age was unexpected. This finding may suggest the need for further refinement and adjustment of this analytical approach.

Three-Dimensional Finite Element Modeling of the Singer’s Formant Cluster Optimization by Epilaryngeal Narrowing With and Without Velopharyngeal Opening

This study aimed to find the optimal geometrical configuration of the vocal tract to increase the total acoustic energy output of human voice in the frequency interval 2-3.5 kHz “singer’s formant cluster”, (SFC) for vowels [a:] and [i:] considering epilaryngeal changes and the velopharyngeal opening (VPO). The study applied 3D volume models of the vocal and nasal tract based on computer tomography (CT) images of a female speaker. The epilaryngeal narrowing (EN) increased the total sound pressure level (SPL) and SPL of the SFC by diminishing the frequency difference between acoustic resonances F3 and F4 for [a:] and between F2 and F3 for [i:]. The effect reached its maximum at the low pharynx/epilarynx cross-sectional area ratio 11.4:1 for [a:] and 25:1 for [i:]. The acoustic results obtained with the model optimization are in good agreement with the results of an internationally recognized operatic alto singer. With the EN and the VPO, the vocal tract input reactance was positive over the entire fo singing range (ca. 75-1500 Hz). The VPO increased the strength of the SFC and diminished the SPL of F1 for both vowels, but with EN the SPL decrease was compensated. The effect of EN is not linear and depends on the vowel. Both the EN and the VPO alone and together can support (singing) voice production.

Synthetic, self-oscillating vocal fold models for voice production researcha).

Sound for the human voice is produced by vocal fold flow-induced vibration and involves a complex coupling between flow dynamics, tissue motion, and acoustics. Over the past three decades, synthetic, self-oscillating vocal fold models have played an increasingly important role in the study of these complex physical interactions. In particular, two types of models have been established: "membranous" vocal fold models, such as a water-filled latex tube, and "elastic solid" models, such as ultrasoft silicone formed into a vocal fold-like shape and in some cases with multiple layers of differing stiffness to mimic the human vocal fold tissue structure. In this review, the designs, capabilities, and limitations of these two types of models are presented. Considerations unique to the implementation of elastic solid models, including fabrication processes and materials, are discussed. Applications in which these models have been used to study the underlying mechanical principles that govern phonation are surveyed, and experimental techniques and configurations are reviewed. Finally, recommendations for continued development of these models for even more lifelike response and clinical relevance are summarized.