Classification of laryngeal diseases including laryngeal cancer, benign mucosal disease, and vocal cord paralysis by artificial intelligence using voice analysis.

Voice change is often the first sign of laryngeal cancer, leading to diagnosis through hospital laryngoscopy. Screening for laryngeal cancer solely based on voice could enhance early detection. However, identifying voice indicators specific to laryngeal cancer is challenging, especially when differentiating it from other laryngeal ailments. This study presents an artificial intelligence model designed to distinguish between healthy voices, laryngeal cancer voices, and those of the other laryngeal conditions. We gathered voice samples of individuals with laryngeal cancer, vocal cord paralysis, benign mucosal diseases, and healthy participants. Comprehensive testing was conducted to determine the best mel-frequency cepstral coefficient conversion and machine learning techniques, with results analyzed in-depth. In our tests, laryngeal diseases distinguishing from healthy voices achieved an accuracy of 0.85-0.97. However, when multiclass classification, accuracy ranged from 0.75 to 0.83. These findings highlight the challenges of artificial intelligence-driven voice-based diagnosis due to overlaps with benign conditions but also underscore its potential.

Speaking without vocal folds using a machine-learning-assisted wearable sensing-actuation system.

Voice disorders resulting from various pathological vocal fold conditions or postoperative recovery of laryngeal cancer surgeries, are common causes of dysphonia. Here, we present a self-powered wearable sensing-actuation system based on soft magnetoelasticity that enables assisted speaking without relying on the vocal folds. It holds a lightweighted mass of approximately 7.2 g, skin-alike modulus of 7.83 × 105 Pa, stability against skin perspiration, and a maximum stretchability of 164%. The wearable sensing component can effectively capture extrinsic laryngeal muscle movement and convert them into high-fidelity and analyzable electrical signals, which can be translated into speech signals with the assistance of machine learning algorithms with an accuracy of 94.68%. Then, with the wearable actuation component, the speech could be expressed as voice signals while circumventing vocal fold vibration. We expect this approach could facilitate the restoration of normal voice function and significantly enhance the quality of life for patients with dysfunctional vocal folds.

Digital Avatars and Personalized Voices-How AI Is Helping to Restore Speech to Patients.

In this Medical News article, Edward Chang, MD, chair of the department of neurological surgery at the University of California, San Francisco Weill Institute for Neurosciences joins JAMA Editor in Chief Kirsten Bibbins-Domingo, PhD, MD, MAS, to discuss the potential for AI to revolutionize communication for those unable to speak due to aphasia.

Catcalls: exotic cats discriminate the voices of familiar caregivers.

Background: The ability to differentiate familiar from unfamiliar humans has been considered a product of domestication or early experience. Few studies have focused on voice recognition in Felidae despite the fact that this family presents the rare opportunity to compare domesticated species to their wild counterparts and to examine the role of human rearing. Methods: We tested whether non-domesticated Felidae species recognized familiar human voices by exposing them to audio playbacks of familiar and unfamiliar humans. In a pilot study, we presented seven cats of five species with playbacks of voices that varied in familiarity and use of the cats' names. In the main study, we presented 24 cats of 10 species with unfamiliar and then familiar voice playbacks using a habituation-dishabituation paradigm. We anticipated that human rearing and use of the cats' names would result in greater attention to the voices, as measured by the latency, intensity, and duration of responses regardless of subject sex and subfamily. Results: Cats responded more quickly and with greater intensity (e.g., full versus partial head turn, both ears moved versus one ear twitching) to the most familiar voice in both studies. They also responded for longer durations to the familiar voice compared to the unfamiliar voices in the main study. Use of the cats' name and rearing history did not significantly impact responding. These findings suggest that close human contact rather than domestication is associated with the ability to discriminate between human voices and that less social species may have socio-cognitive abilities akin to those of more gregarious species. With cats of all species being commonly housed in human care, it is important to know that they differentiate familiar from unfamiliar human voices.

Emotional expressivity in singing. Assessing physiological and acoustic indicators of two opera singers' voice characteristics.

In an earlier study, we analyzed how audio signals obtained from three professional opera singers varied when they sang one octave wide eight-tone scales in ten different emotional colors. The results showed systematic variations in voice source and long-term-average spectrum (LTAS) parameters associated with major emotion "families". For two of the singers, subglottal pressure (PSub) also was recorded, thus allowing analysis of an additional main physiological voice control parameter, glottal resistance (defined as the ratio between PSub and glottal flow), and related to glottal adduction. In the present study, we analyze voice source and LTAS parameters derived from the audio signal and their correlation with Psub and glottal resistance. The measured parameters showed a systematic relationship with the four emotion families observed in our previous study. They also varied systematically with values of the ten emotions along the valence, power, and arousal dimensions; valence showed a significant correlation with the ratio between acoustic voice source energy and subglottal pressure, while Power varied significantly with sound level and two measures related to the spectral dominance of the lowest spectrum partial. the fundamental.

Immediate effect of recurrent laryngeal nerve stimulation in patients with idiopathic unilateral vocal fold paralysis.

BACKGROUND: There is a lack of effective treatment for idiopathic unilateral vocal fold paralysis (IUVFP). A better phonation was reported by patients after laryngeal nerve stimulation during our clinical examination. OBJECTIVES: This study aims to investigate immediate effect of recurrent laryngeal nerve (RLN) stimulation on phonation in patients with IUVFP. MATERIAL AND METHODS: Sixty-two patients with clinically identified IUVFP underwent RLN stimulation with needle electrodes. Laryngoscopy, acoustic analysis, and voice perception assessment were performed for quantitative comparison of vocal function and voice quality before and after the intervention. RESULTS: Laryngoscopic images showed a larger motion range of the paralyzed vocal fold (p < .01) and better glottal closure (p < .01) after RLN stimulation. Acoustic analysis revealed that the dysphonia severity index increased significantly (p < .01) while the jitter and shimmer decreased after the intervention (p < .05). According to perceptual evaluation, RLN stimulation significantly increased RBH grades in patients with IUVFP (p < .01). Furthermore, the improvement in voice perception had a moderate positive correlation with the decrease in the glottal closure. CONCLUSIONS AND SIGNIFICANCE: This study shows a short-term improvement of phonation in IUVFP patients after RLN stimulation, which provides proof-of-concept for trialing a controlled delivery of RLN stimulation and assessing durability of any observed responses.

Test-Retest Reliability of Behavioral Assays of Feedforward and Feedback Auditory-Motor Control of Voice and Articulation.

PURPOSE: Behavioral assays of feedforward and feedback auditory-motor control of voice and articulation frequently are used to make inferences about underlying neural mechanisms and to study speech development and disorders. However, no studies have examined the test-retest reliability of such measures, which is critical for rigorous study of auditory-motor control. Thus, the purpose of the present study was to assess the reliability of assays of feedforward and feedback control in voice versus articulation domains. METHOD: Twenty-eight participants (14 cisgender women, 12 cisgender men, one transgender man, one transmasculine/nonbinary) who denied any history of speech, hearing, or neurological impairment were measured for responses to predictable versus unexpected auditory feedback perturbations of vocal (fundamental frequency, fo) and articulatory (first formant, F1) acoustic parameters twice, with 3-6 weeks between sessions. Reliability was measured with intraclass correlations. RESULTS: Opposite patterns of reliability were observed for fo and F1; fo reflexive responses showed good reliability and fo adaptive responses showed poor reliability, whereas F1 reflexive responses showed poor reliability and F1 adaptive responses showed moderate reliability. However, a criterion-referenced categorical measurement of fo adaptive responses as typical versus atypical showed substantial test-retest agreement. CONCLUSIONS: Individual responses to some behavioral assays of auditory-motor control of speech should be interpreted with caution, which has implications for several fields of research. Additional research is needed to establish reliable criterion-referenced measures of F1 adaptive responses as well as fo and F1 reflexive responses. Furthermore, the opposite patterns of test-retest reliability observed for voice versus articulation add to growing evidence for differences in underlying neural control mechanisms.

Acoustic and Physiologic Correlates of Vocal Effort in Individuals With and Without Primary Muscle Tension Dysphonia.

OBJECTIVES: The aims of this study were to determine relationships between vocal effort and (a) acoustic correlates of vocal output and (b) supraglottic compression in individuals with primary muscle tension dysphonia (pMTD) and without voice disorders (controls) in the context of a vocal load challenge. METHOD: Twenty-six individuals with pMTD and 35 vocally healthy controls participated in a 30-min vocal load challenge. The pre- and postload relationships among self-ratings of vocal effort, various acoustic voice measures, and supraglottic compression (mediolateral and anteroposterior) were tested with multiple regression models and post hoc Pearson's correlations. Acoustic measures included cepstral peak prominence (CPP), low-to-high spectral ratio, difference in intensity between the first two harmonics, fundamental frequency, and sound pressure level (dB SPL). RESULTS: Regression models for CPP and mediolateral compression were statistically significant. Vocal effort, diagnosis of pMTD, and vocal demand were each significant variables influencing CPP measures. CPP was lower in the pMTD group across stages. There was no statistical change in CPP following the vocal load challenge within either group, but both groups had an increase in vocal effort postload. Vocal effort and diagnosis influenced the mediolateral compression model. Mediolateral compression was higher in the pMTD group across stages and had a negative relationship with vocal effort, but it did not differ after vocal loading. CONCLUSIONS: CPP and mediolateral supraglottic compression were influenced by vocal effort and diagnosis of pMTD. Increased vocal effort was associated with lower CPP, particularly after vocal load, and decreased mediolateral supraglottic compression in the pMTD group.

Systematic Review of Literature on Vocal Demand Response: Understanding Physiology, Measurements, and Associated Factors.

PURPOSE: Considering the conceptual migration from vocal load and vocal loading to vocal demand and vocal demand response, this review of literature aimed to identify physiological explanations, reported measurements, and associated factors (vocal demands) reported in the literature when considering the phonatory response to a vocal demand. METHODS: A systematic review of literature, following the PRISMA Statement, was conducted using Web of Science, PubMed, Scopus, and ScienceDirect. Data were analyzed and presented in two parts. First, a bibliometric analysis, co-occurrence analysis, and content analysis were performed. Three criteria that got article inclusion were defined: (1) written in English, Spanish, and Portuguese; (2) published between 2009 and 2021; and (3) focused on vocal load and loading, vocal demand response, and voice assessment parameters. A total of 54 publications met the criteria and were included in this review. The second part included a conceptual framework based on the content analysis of three aspects of vocal demand response: (1) physiological explanations, (2) reported measurements, and (3) vocal demands. RESULTS AND CONCLUSION: As would be expected since vocal demand response is a relatively new term and not yet commonly used in literature when discussing way that the speakers respond to communicative scenarios, most of the studies reviewed (both historical and recent) still use the term of vocal load and vocal loading. Although there is a broad variety of literature discussing a wide range of vocal demands and voice parameters used to characterize the vocal demand response, results show that there is consistency across the studies. While vocal demand response is unique and intrinsic to the talker, associated factors that contribute to this response include both internal talker and external talker factors. Internal factors include muscle stiffness, viscosity in the phonatory system, vocal fold tissue damage, elevated sound pressure levels during occupational voice demands, extended periods of voice use, suboptimal body posture, difficulties in breathing technique, and sleep disturbances. Associated external factors include the working environment (noise, acoustics, temperature, humidity). In conclusion, although vocal demand response is intrinsic to the speaker, the speaker's response is affected by external vocal demands. However, due to the wide methods to evaluate vocal demand response, it has been difficult to establish its contribution to voice disorders in the general population and, specifically, among occupational voice users. This literature review identified commonly reported parameters and factors that may help clinicians and researchers define vocal demand response.

Effects of Thyroarytenoid Activation Induced Vibratory Asymmetry on Voice Acoustics and Perception.

INTRODUCTION: Asymmetry of vocal fold (VF) vibration is common in patients with voice complaints and also observed in 10% of normophonic individuals. Although thyroarytenoid (TA) muscle activation plays a crucial role in regulating VF vibration, how TA activation asymmetry relates to voice acoustics and perception is unclear. We evaluated the relationship between TA activation asymmetry and the resulting acoustics and perception. METHODS: An in vivo canine model of phonation was used to create symmetric and increasingly asymmetric VF vibratory conditions via graded stimulation of bilateral TA muscles. Naïve listeners (n = 89) rated the perceptual quality of 100 unique voice samples using a visual sort-and-rate task. For each phonatory condition, cepstral peak prominence (CPP), harmonic amplitude (H1-H2), and root-mean-square (RMS) energy of the voice were measured. The relationships between these metrics, vibratory asymmetry, and perceptual ratings were evaluated. RESULTS: Increasing levels of TA asymmetry resulted in declining listener preference. Furthermore, only severely asymmetric audio samples were perceptually distinguishable from symmetric and mildly asymmetric conditions. CPP was negatively correlated with TA asymmetry: voices produced with larger degrees of asymmetry were associated with lower CPP values. Listeners preferred audio samples with higher values of CPP, high RMS energy, and lower H1-H2 (less breathy). CONCLUSION: Listeners are sensitive to changes in voice acoustics related to vibratory asymmetry. Although increasing vibratory asymmetry is correlated with decreased perceptual ratings, mild asymmetries are perceptually tolerated. This study contributes to our understanding of voice production and quality by identifying perceptually salient and clinically meaningful asymmetry. LEVEL OF EVIDENCE: N/A (Basic Science Study) Laryngoscope, 134:1327-1332, 2024.

Impairment of the internal forward model and feedback mechanisms for vocal sensorimotor control in post-stroke aphasia: evidence from directional responses to altered auditory feedback.

The present study examined opposing and following vocal responses to altered auditory feedback (AAF) to determine how damage to left-hemisphere brain networks impairs the internal forward model and feedback mechanisms in post-stroke aphasia. Forty-nine subjects with aphasia and sixty age-matched controls performed speech vowel production tasks while their auditory feedback was altered using randomized ± 100 cents upward and downward pitch-shift stimuli. Data analysis revealed that when vocal responses were averaged across all trials (i.e., opposing and following), the overall magnitude of vocal compensation was significantly reduced in the aphasia group compared with controls. In addition, when vocal responses were analyzed separately for opposing and following trials, subjects in the aphasia group showed a significantly lower percentage of opposing and higher percentage of following vocal response trials compared with controls, particularly for the upward pitch-shift stimuli. However, there was no significant difference in the magnitude of opposing and following vocal responses between the two groups. These findings further support previous evidence on the impairment of vocal sensorimotor control in aphasia and provide new insights into the distinctive impact of left-hemisphere stroke on the internal forward model and feedback mechanisms. In this context, we propose that the lower percentage of opposing responses in aphasia may be accounted for by deficits in feedback-dependent mechanisms of audio-vocal integration and motor control. In addition, the higher percentage of following responses may reflect aberrantly increased reliance of the speech system on the internal forward model for generating sensory predictions during vocal error detection and motor control.

A Tutorial on Skeletal Muscle Metabolism and the Role of Blood Lactate: Implications for Speech Production.

PURPOSE: The purpose of this tutorial is threefold: (a) present relevant exercise science literature on skeletal muscle metabolism and synthesize the limited available research on metabolism of the adult human speech musculature in an effort to elucidate the role of metabolism in speech production; (b) introduce a well-studied metabolic serum biomarker in exercise science, lactate, and the potential usefulness of investigating this metabolite, through a well-established exercise science methodology, to better understand metabolism of the musculature involved in voice production; and (c) discuss exercise physiology considerations for future voice science research that seeks to investigate blood lactate and metabolism in voice physiology in an ecologically valid manner. METHOD: This tutorial begins with relevant exercise science literature on the basic cellular processes of muscle contraction that require energy and the metabolic mechanisms that regenerate the energy required for task execution. The tutorial next synthesizes the available research investigating metabolism of the adult human speech musculature. This is followed by the authors proposing a hypothesis of speech metabolism based on the voice science literature and the application of well-studied exercise science principles of muscle physiology. The tutorial concludes with a discussion and the potential usefulness of lactate in investigations to better understand the metabolism of the musculature involved in vocal demand tasks. CONCLUSION: The role of metabolism during speech (respiratory, laryngeal, and articulatory) is an understudied yet critical aspect of speech physiology that warrants further study to better understand the metabolic systems that are used to meet vocal demands.

Immunoactivation Affects Perceived Body Odor and Facial but Not Vocal Attractiveness.

Several previous studies have shown that in mammals, the health status of conspecifics can be assessed based on perceptual cues. Olfactory, visual, or acoustic cues may lead to avoidant behavior, thus reducing the risk of contagion by close contact with infected individuals. We tested whether immune system activation after immunization leads to perceptible changes in body odor and facial and vocal attractiveness in humans. We have experimentally activated the immune system of male participants using vaccination against hepatitis A/B and meningococcus. Their body odor, facial photographs, and vocal recordings were collected before and 14 days after vaccination. Subsequently, the body odor samples, facial photographs, and vocal recordings were assessed by female raters for their attractiveness and healthiness. We have also measured skin coloration (from facial photographs and in vivo using a spectrophotometer), vocal parameters, and C-reactive protein (CRP) levels as a marker of inflammation. We found an increase in perceived body odor attractiveness, a decrease in facial attractiveness and healthiness, and no change in vocal attractiveness 14 days after vaccination compared to the prevaccination condition. Moreover, there was no change in facial coloration or vocal parameters between the prevaccination and postvaccination conditions. Prevaccination CRP levels were negatively associated with body odor and facial attractiveness and positively associated with body odor intensity. Overall, our results suggest that perceived body odor as well as facial but not vocal attractiveness may provide cues to activation of the immune response and that each modality may carry specific information about the individual's condition.

Modifications of auditory feedback and its effects on the voice of adult subjects: a scoping review. / Modificações do feedback auditivo e seus efeitos sobre a voz de indivíduos adultos: uma revisão de escopo.

INTRODUCTION: The auditory perception of voice and its production involve auditory feedback, kinesthetic cues and the feedforward system that produce different effects for the voice. The Lombard, Sidetone and Pitch-Shift-Reflex effects are the most studied. The mapping of scientific experiments on changes in auditory feedback for voice motor control makes it possible to examine the existing literature on the phenomenon and may contribute to voice training or therapies. PURPOSE: To map experiments and research results with manipulation of auditory feedback for voice motor control in adults. METHOD: Scope review following the Checklist Preferred Reporting Items for Systematic reviews and Meta-Analyses extension (PRISMA-ScR) to answer the question: "What are the investigation methods and main research findings on the manipulation of auditory feedback in voice self-monitoring of adults?". The search protocol was based on the Population, Concept, and Context (PCC) mnemonic strategy, in which the population is adult individuals, the concept is the manipulation of auditory feedback and the context is on motor voice control. Articles were searched in the databases: BVS/Virtual Health Library, MEDLINE/Medical Literature Analysis and Retrieval System online, COCHRANE, CINAHL/Cumulative Index to Nursing and Allied Health Literature, SCOPUS and WEB OF SCIENCE. RESULTS: 60 articles were found, 19 on the Lombard Effect, 25 on the Pitch-shift-reflex effect, 12 on the Sidetone effect and four on the Sidetone/Lombard effect. The studies are in agreement that the insertion of a noise that masks the auditory feedback causes an increase in the individual's speech intensity and that the amplification of the auditory feedback promotes the reduction of the sound pressure level in the voice production. A reflex response to the change in pitch is observed in the auditory feedback, however, with particular characteristics in each study. CONCLUSION: The material and method of the experiments are different, there are no standardizations in the tasks, the samples are varied and often reduced. The methodological diversity makes it difficult to generalize the results. The main findings of research on auditory feedback on voice motor control confirm that in the suppression of auditory feedback, the individual tends to increase the intensity of the voice. In auditory feedback amplification, the individual decreases the intensity and has greater control over the fundamental frequency, and in frequency manipulations, the individual tends to correct the manipulation. The few studies with dysphonic individuals show that they behave differently from non-dysphonic individuals.

INTRODUçÃO: A percepção auditiva da voz e sua produção envolvem o feedback auditivo, as pistas cinestésicas e o sistema de feedforward, os quais produzem efeitos distintos para a voz. Os efeitos Lombard, Sidetone e o Pitch-Shift-Reflex são os mais estudados. O mapeamento de experimentos científicos sobre as modificações do feedback auditivo para o controle motor da voz possibilita examinar a literatura existente sobre o fenômeno e pode contribuir para o treinamento ou terapias da voz. OBJETIVO: Mapear os experimentos e resultados das pesquisas com manipulação do feedback auditivo para o controle motor da voz de indivíduos adultos. MÉTODO: Revisão de escopo seguindo o Checklist Preferred Reporting Items for Systematic reviews and Meta-Analyses extension (PRISMA-ScR) para responder à pergunta: "Quais os métodos de investigação e principais achados das pesquisas sobre a manipulação do feedback auditivo no automonitoramento da voz de indivíduos adultos?". O protocolo de busca foi baseado na estratégia mnemônica População, Conceito e Contexto (PCC). A população são os indivíduos adultos; o conceito é a manipulação do feedback auditivo e o contexto é o controle motor da voz. Os artigos foram pesquisados nas bases de dados: BVS/ Biblioteca Virtual em Saúde, MEDLINE/Medical Literature Analysis and Retrieval Sistem on-line, COCHRANE, CINAHL/Cumulative Index to Nursing and Allied Health Literature, SCOPUS e WEB OF SCIENCE. RESULTADOS: Foram encontrados 60 artigos, sendo 19 da temática do Efeito Lombard, 25 do efeito Pitch-shift-reflex, 12 do efeito Sidetone e quatro sobre o efeito Sidetone/Lombard. Os estudos são concordantes que a inserção de um ruído que mascara o feedback auditivo provoca um aumento na intensidade de fala do indivíduo e que a amplificação do feedback auditivo promove a redução do nível de pressão sonora na produção da voz. Observa-se uma resposta reflexa à mudança de tom no feedback auditivo, porém, com características individuais em cada estudo. CONCLUSÃO: O material e método dos experimentos são distintos, não há padronizações nas tarefas, as amostras são variadas, muitas vezes reduzidas. A diversidade metodológica dificulta a generalização dos resultados. Os principais achados das pesquisas a respeito o feedback auditivo sobre o controle motor da voz confirmam que, na supressão do feedback auditivo, o indivíduo tende a aumentar a intensidade da voz. Na amplificação do feedback auditivo, o indivíduo diminui a intensidade e tem maior controle sobre a frequência fundamental e, nas manipulações da frequência, o indivíduo tende a corrigir a manipulação. Os poucos estudos com sujeitos disfônicos mostram que eles se comportam diferentemente dos não disfônicos.

Preterm infants show an atypical processing of the mother's voice.

To understand the consequences of prematurity on language perception, it is fundamental to determine how atypical early sensory experience affects brain development. At term equivalent age, ten preterm and ten full-term newborns underwent high-density EEG during mother or stranger speech presentation, in the forward or backward order. A general group effect terms > preterms is evident in the theta frequency band, in the left temporal area, with preterms showing significant activation for strangers' and terms for the mother's voice. A significant group contrast in the low and high theta in the right temporal regions indicates higher activations for the stranger's voice in preterms. Finally, only full terms presented a late gamma band increase for the maternal voice, indicating a more mature brain response. EEG time-frequency analysis demonstrate that preterm infants are selectively responsive to stranger voices in both temporal hemispheres, and that they lack selective brain responses to their mother's forward voice.

Singing in different performance spaces: The effect of room acoustics on singers' perception.

Classical singers' performances vary across different acoustic environments. The changes in the delivery are influenced by the singer's perception of the venue's acoustics. This study investigated these relationships using nine professional or semi-professional classical singers. Participants performed Giordani's "Caro mio ben" aria in five venues, and the acoustic parameters reverberance (T30 and EDT), clarity (C80), early vocal support (STv), and tonal color (EDTf) were measured. From a factor analysis of the subjective analysis three major factors emerged that, we propose, would represent three generalized percepts of Room Supportiveness, Room Noiselessness, and Room Timbre. These percepts correlated significantly with objective acoustic parameters traditionally linked to vocal support, reverberation, and timbre. Room Supportiveness and Room Noiselessness significantly contributed to the singers' likability of the acoustic environment, while Room Timbre did not. This indicates that singers' perceptual preference for a performance space may be influenced by factors affecting both auditory feedback and vocal function. These findings underscore the need for performing space designers to consider the unique needs of all stakeholders, including listeners and performers. The study contributes to the bridging of the gap between subjective perceptions and objective measurements, providing valuable insights for acoustic design considerations.

An Euler-Bernoulli-type beam model of the vocal folds for describing curved and incomplete glottal closure patterns.

Incomplete glottal closure is a laryngeal configuration wherein the glottis is not fully obstructed prior to phonation. It has been linked to inefficient voice production and voice disorders. Various incomplete glottal closure patterns can arise and the mechanisms driving them are not well understood. In this work, we introduce an Euler-Bernoulli composite beam vocal fold (VF) model that produces qualitatively similar incomplete glottal closure patterns as those observed in experimental and high-fidelity numerical studies, thus offering insights into the potential underlying physical mechanisms. Refined physiological insights are pursued by incorporating the beam model into a VF posturing model that embeds the five intrinsic laryngeal muscles. Analysis of the combined model shows that co-activating the lateral cricoarytenoid (LCA) and interarytenoid (IA) muscles without activating the thyroarytenoid (TA) muscle results in a bowed (convex) VF geometry with closure at the posterior margin only; this is primarily attributed to the reactive moments at the anterior VF margin. This bowed pattern can also arise during VF compression (due to extrinsic laryngeal muscle activation for example), wherein the internal moment induced passively by the TA muscle tissue is the predominant mechanism. On the other hand, activating the TA muscle without incorporating other adductory muscles results in anterior and mid-membranous glottal closure, a concave VF geometry, and a posterior glottal opening driven by internal moments induced by TA muscle activation. In the case of initial full glottal closure, the posterior cricoarytenoid (PCA) muscle activation cancels the adductory effects of the LCA and IA muscles, resulting in a concave VF geometry and posterior glottal opening. Furthermore, certain maneuvers involving co-activation of all adductory muscles result in an hourglass glottal shape due to a reactive moment at the anterior VF margin and moderate internal moment induced by TA muscle activation. These findings have implications regarding potential laryngeal maneuvers in patients with voice disorders involving imbalances or excessive tension in the laryngeal muscles such as muscle tension dysphonia.

Speech motor adaptation during synchronous and metronome-timed speech.

Sensorimotor integration during speech has been investigated by altering the sound of a speaker's voice in real time; in response, the speaker learns to change their production of speech sounds in order to compensate (adaptation). This line of research has however been predominantly limited to very simple speaking contexts, typically involving (a) repetitive production of single words and (b) production of speech while alone, without the usual exposure to other voices. This study investigated adaptation to a real-time perturbation of the first and second formants during production of sentences either in synchrony with a prerecorded voice (synchronous speech group) or alone (solo speech group). Experiment 1 (n = 30) found no significant difference in the average magnitude of compensatory formant changes between the groups; however, synchronous speech resulted in increased between-individual variability in such formant changes. Participants also showed acoustic-phonetic convergence to the voice they were synchronizing with prior to introduction of the feedback alteration. Furthermore, the extent to which the changes required for convergence agreed with those required for adaptation was positively correlated with the magnitude of subsequent adaptation. Experiment 2 tested an additional group with a metronome-timed speech task (n = 15) and found a similar pattern of increased between-participant variability in formant changes. These findings demonstrate that speech motor adaptation can be measured robustly at the group level during performance of more complex speaking tasks; however, further work is needed to resolve whether self-voice adaptation and other-voice convergence reflect additive or interactive effects during sensorimotor control of speech. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Right, but not left, posterior superior temporal gyrus is causally involved in vocal feedback control.

The posterior superior temporal gyrus (pSTG) has been implicated in the integration of auditory feedback and motor system for controlling vocal production. However, the question as to whether and how the pSTG is causally involved in vocal feedback control is currently unclear. To this end, the present study selectively stimulated the left or right pSTG with continuous theta burst stimulation (c-TBS) in healthy participants, then used event-related potentials to investigate neurobehavioral changes in response to altered auditory feedback during vocal pitch regulation. The results showed that, compared to control (vertex) stimulation, c-TBS over the right pSTG led to smaller vocal compensations for pitch perturbations accompanied by smaller cortical N1 and larger P2 responses. Enhanced P2 responses received contributions from the right-lateralized temporal and parietal regions as well as the insula, and were significantly correlated with suppressed vocal compensations. Surprisingly, these effects were not found when comparing c-TBS over the left pSTG with control stimulation. Our findings provide evidence, for the first time, that supports a causal relationship between right, but not left, pSTG and auditory-motor integration for vocal pitch regulation. This lends support to a right-lateralized contribution of the pSTG in not only the bottom-up detection of vocal feedback errors but also the involvement of driving motor commands for error correction in a top-down manner.

Atypical Activation of Laryngeal Somatosensory-Motor Cortex During Vocalization in People With Unexplained Chronic Cough.

Importance: Unexplained chronic cough is common and has substantial negative quality-of-life implications, yet its causes are not well understood. A better understanding of how peripheral and central neural processes contribute to chronic cough is essential for treatment design. Objective: To determine if people with chronic cough exhibit signs of abnormal neural processing over laryngeal sensorimotor cortex during voluntary laryngeal motor activity such as vocalization. Design, Setting, and Participants: This was a cross-sectional study of a convenience sample of participants with chronic cough and healthy participants. Testing was performed in an acoustically and electromagnetically shielded chamber. In a single visit, electroencephalographic (EEG) signals were recorded from participants with chronic cough and healthy participants during voice production. The chronic cough group participants presented with unexplained cough of 8 weeks or longer duration with prior medical evaluation including negative results of chest imaging. None of the participants had a history of any neurologic disease known to impair vocalization or swallowing. Data collection for the healthy control group occurred from February 2 to June 28, 2018, and for the chronic cough group, from November 22, 2021, to June 21, 2022. Data analysis was performed from May 1 to October 30, 2022. Exposure: Participants with or without chronic cough. Main Outcome Measures: Event-related spectral perturbation over the laryngeal area of somatosensory-motor cortex from 0 to 30 Hz (ie, θ, α, and ß bands) and event-related coherence as a measure of synchronous activity between somatosensory and motor cortical regions. Results: The chronic cough group comprised 13 participants with chronic cough (mean [SD] age, 63.5 [7.8] years; 9 women and 4 men) and the control group, 10 healthy age-matched individuals (mean [SD] age, 60.3 [13.9] years; 6 women and 4 men). In the chronic cough group, the typical movement-related desynchronization over somatosensory-motor cortex during vocalization was significantly reduced across θ, α, and ß frequency bands when compared with the control group. Conclusions and Relevance: This cross-sectional study found that the typical movement-related suppression of brain oscillatory activity during vocalization is weak or absent in people with chronic cough. Thus, chronic cough affects sensorimotor cortical activity during the asymptomatic voluntary activation of laryngeal muscles.