An investigation of acoustic cues to tonal registers and voicing in Donglei Kama).

The Kam language has experienced historical tonal splits, resulting in the development of a complex tonal system. However, there is still limited knowledge regarding the acoustic characteristics associated with aspiration-based tone splitting. This study aims to investigate the acoustic cues related to the tonal registers and laryngeal configurations in Donglei Kam, a dialect of Southern Kam. Sixteen native speakers of Donglei Kam participated, producing lexical tones. Statistical analyses were conducted to examine the acoustic distinctions between tonal registers, using measurements of voice onset time, spectral tilt, noise, and energy. The results indicated that Donglei Kam retained a two-way contrast of aspiration, albeit with a trend toward gradual loss. Additionally, a breathy voice was detected in the Ciyin tonal register, characterized by elevated spectral tilt values and spectral noise throughout the vowels. Moreover, machine learning classifiers effectively identified tonal registers using voice-quality data, suggesting that the phonation contrast between breathy and modal voice could contribute to the tonal split alongside pitch contrast. In summary, these findings enhance our understanding of the acoustic implementation of breathiness in Kam and offer valuable insights into the role of laryngeal contrast in tonal splits.

Principal dimensions of voice production and their role in vocal expression.

How we produce and perceive voice is constrained by laryngeal physiology and biomechanics. Such constraints may present themselves as principal dimensions in the voice outcome space that are shared among speakers. This study attempts to identify such principal dimensions in the voice outcome space and the underlying laryngeal control mechanisms in a three-dimensional computational model of voice production. A large-scale voice simulation was performed with parametric variations in vocal fold geometry and stiffness, glottal gap, vocal tract shape, and subglottal pressure. Principal component analysis was applied to data combining both the physiological control parameters and voice outcome measures. The results showed three dominant dimensions accounting for at least 50% of the total variance. The first two dimensions describe respiratory-laryngeal coordination in controlling the energy balance between low- and high-frequency harmonics in the produced voice, and the third dimension describes control of the fundamental frequency. The dominance of these three dimensions suggests that voice changes along these principal dimensions are likely to be more consistently produced and perceived by most speakers than other voice changes, and thus are more likely to have emerged during evolution and be used to convey important personal information, such as emotion and larynx size.

The breath shape controls intonation of mouse vocalizations.

Intonation in speech is the control of vocal pitch to layer expressive meaning to communication, like increasing pitch to indicate a question. Also, stereotyped patterns of pitch are used to create distinct sounds with different denotations, like in tonal languages and, perhaps, the 10 sounds in the murine lexicon. A basic tone is created by exhalation through a constricted laryngeal voice box, and it is thought that more complex utterances are produced solely by dynamic changes in laryngeal tension. But perhaps, the shifting pitch also results from altering the swiftness of exhalation. Consistent with the latter model, we describe that intonation in most vocalization types follows deviations in exhalation that appear to be generated by the re-activation of the cardinal breathing muscle for inspiration. We also show that the brainstem vocalization central pattern generator, the iRO, can create this breath pattern. Consequently, ectopic activation of the iRO not only induces phonation, but also the pitch patterns that compose most of the vocalizations in the murine lexicon. These results reveal a novel brainstem mechanism for intonation.

Consistency of the Signature of Phonotraumatic Vocal Hyperfunction Across Different Ambulatory Voice Measures.

PURPOSE: Although different factors and voice measures have been associated with phonotraumatic vocal hyperfunction (PVH), it is unclear what percentage of individuals with PVH exhibit such differences during their daily lives. This study used a machine learning approach to quantify the consistency with which PVH manifests according to ambulatory voice measures. Analyses included acoustic parameters of phonation as well as temporal aspects of phonation and rest, with the goal of determining optimally consistent signatures of PVH. METHOD: Ambulatory neck-surface acceleration signals were recorded over 1 week from 116 female participants diagnosed with PVH and age-, sex-, and occupation-matched vocally healthy controls. The consistency of the manifestation of PVH was defined as the percentage of participants in each group that exhibited an atypical signature based on a target voice measure. Evaluation of each machine learning model used nested 10-fold cross-validation to improve the generalizability of findings. In Experiment 1, we trained separate logistic regression models based on the distributional characteristics of 14 voice measures and durations of voicing and resting segments. In Experiments 2 and 3, features of voicing and resting duration augmented the existing distributional characteristics to examine whether more consistent signatures would result. RESULTS: Experiment 1 showed that the difference in the magnitude of the first two harmonics (H1-H2) exhibited the most consistent signature (69.4% of participants with PVH and 20.4% of controls had an atypical H1-H2 signature), followed by spectral tilt over eight harmonics (73.6% participants with PVH and 32.1% of controls had an atypical spectral tilt signature) and estimated sound pressure level (SPL; 66.9% participants with PVH and 27.6% of controls had an atypical SPL signature). Additionally, 77.6% of participants with PVH had atypical resting duration, with 68.9% exhibiting atypical voicing duration. Experiments 2 and 3 showed that augmenting the best-performing voice measures with univariate features of voicing or resting durations yielded only incremental improvement in the classifier's performance. CONCLUSIONS: Females with PVH were more likely to use more abrupt vocal fold closure (lower H1-H2), phonate louder (higher SPL), and take shorter vocal rests. They were also less likely to use higher fundamental frequency during their daily activities. The difference in the voicing duration signature between participants with PVH and controls had a large effect size, providing strong empirical evidence regarding the role of voice use in the development of PVH.

Systematic Review: Singing-Based Interventions to Improve Physical Functions Related to Aging Voice in Older Adults.

PURPOSE: This systematic review aimed to evaluate the effects of singing as an intervention for aging voice. METHOD: Quantitative studies of interventions for older adults with any medical condition that involves singing as training were reviewed, measured by respiration, phonation, and posture, which are the physical functions related to the aging voice. English and Chinese studies published until April 2024 were searched using 31 electronic databases, and seven studies were included. The included articles were assessed according to the Grading of Recommendations, Assessment, Development, and Evaluations rubric. RESULTS: Seven studies were included. These studies reported outcome measures that were related to respiratory functions only. For the intervention effect, statistically significant improvements were observed in five of the included studies, among which three studies had large effect sizes. The overall level of evidence of the included studies was not high, with three studies having moderate levels and the rest having lower levels. The intervention activities included trainings other than singing. These non-singing training items may have caused co-intervention bias in the study results. CONCLUSIONS: This systematic review suggests that singing as an intervention for older adults with respiratory and cognitive problems could improve respiration and respiratory-phonatory control. However, none of the included studies covers the other two of the physical functions related to aging voice (phonatory and postural functions). The overall level of evidence of the included studies was not high either. There is a need for more research evidence in singing-based intervention specifically for patient with aging voice.

Biomechanics of sound production in high-pitched classical singing.

Voice production of humans and most mammals is governed by the MyoElastic-AeroDynamic (MEAD) principle, where an air stream is modulated by self-sustained vocal fold oscillation to generate audible air pressure fluctuations. An alternative mechanism is found in ultrasonic vocalizations of rodents, which are established by an aeroacoustic (AA) phenomenon without vibration of laryngeal tissue. Previously, some authors argued that high-pitched human vocalization is also produced by the AA principle. Here, we investigate the so-called "whistle register" voice production in nine professional female operatic sopranos singing a scale from C6 (≈ 1047 Hz) to G6 (≈ 1568 Hz). Super-high-speed videolaryngoscopy revealed vocal fold collision in all participants, with closed quotients from 30 to 73%. Computational modeling showed that the biomechanical requirements to produce such high-pitched voice would be an increased contraction of the cricothyroid muscle, vocal fold strain of about 50%, and high subglottal pressure. Our data suggest that high-pitched operatic soprano singing uses the MEAD mechanism. Consequently, the commonly used term "whistle register" does not reflect the physical principle of a whistle with regard to voice generation in high pitched classical singing.

Changes in and clinical utility of maximum phonation time and repetitive saliva swallowing test scores after esophagectomy.

BACKGROUND: Postoperative pneumonia in patients with esophageal cancer occurs due to swallowing dysfunction and aspiration. Recently, maximum phonation time (MPT) assessment and repetitive saliva swallowing test (RSST) have been focused on as swallowing function assessment methods that can identify patients as high risk for pneumonia. We aimed to evaluate the clinical utility of MPT assessment and RSST in patients undergoing oncological esophagectomy. METHODS: In total, 47 consecutive patients who underwent esophagectomy for esophageal cancer between August 2020 and July 2023 were eligible. The perioperative changes in MPTs and RSST scores were examined. In addition, univariate and multivariate analyses were performed to identify the predictive factors of postoperative pneumonia. RESULTS: The median MPTs before surgery and on postoperative days (PODs) 3, 6, and 10 were 18.4, 7.2, 10.6, and 12.4 s, respectively; postoperative MPTs were significantly lower than preoperative MPT. In addition, the MPT of POD 6 was significantly longer than that of POD 3 (P < 0.05). Meanwhile, there were no significant changes in perioperative RSST scores. Overall, 8 of 47 patients (17.0%) developed pneumonia postoperatively. A short MPT on POD 6 was one of the independent predictive factors for the incidence of postoperative pneumonia (odds ratio: 12.6, 95% confidence interval: 1.29-123, P = 0.03) in the multivariate analysis. CONCLUSIONS: The MPT significantly decreased after esophagectomy. However, the RSST score did not. The MPT on POD6 can be a predictor of postoperative pneumonia.

Immediate effect of inspiratory exercise with exerciser and respiratory encourager in women without vocal complaints. / Efeito imediato de exercício inspiratório com exercitador e incentivador respiratório em mulheres sem queixas vocais.

PURPOSE: To evaluate the immediate effect of the inspiratory exercise with a booster and a respiratory exerciser on the voice of women without vocal complaints. METHODS: 25 women with no vocal complaints, between 18 and 34 years old, with a score of 1 on the Vocal Disorder Screening Index (ITDV) participated. Data collection was performed before and after performing the inspiratory exercise and consisted of recording the sustained vowel /a/, connected speech and maximum phonatory times (MPT) of vowels, fricative phonemes and counting numbers. In the auditory-perceptual judgment, the Vocal Deviation Scale (VSD) was used to verify the general degree of vocal deviation. Acoustic evaluation was performed using the PRAAT software and the parameters fundamental frequency (f0), jitter, shimmer, harmonium-to-noise ratio (HNR), Cepstral Peak Prominence Smoothed (CPPS), Acoustic Voice Quality Index (AVQI) and Acoustic Breathiness Index (ABI). To measure the aerodynamic measurements, the time of each emission was extracted in the Audacity program. Data were statistically analyzed using the Statistica for Windows software and normality was tested using the Shapiro-Wilk test. To compare the results, Student's and Wilcoxon's t tests were applied, adopting a significance level of 5%. RESULTS: There were no significant differences between the results of the JPA and the acoustic measures, in the pre and post inspiratory exercise moments. As for the aerodynamic measures, it was possible to observe a significant increase in the value of the TMF /s/ (p=0.008). CONCLUSION: There was no change in vocal quality after the inspiratory exercise with stimulator and respiratory exerciser, but an increase in the MPT of the phoneme /s/ was observed after the exercise.

OBJETIVO: Avaliar o efeito imediato do exercício inspiratório com incentivador e exercitador respiratório na voz de mulheres sem queixas vocais. MÉTODO: Participaram 25 mulheres sem queixas vocais, entre 18 e 34 anos, com pontuação 1 no Índice de Triagem para Distúrbio Vocal (ITDV). A coleta de dados foi realizada nos momentos antes e após realização de exercício inspiratório e consistiu na gravação de vogal sustentada /a/, fala encadeada e tempos máximos fonatórios (TMF) de vogais, fonemas fricativos e contagem de números. No julgamento perceptivo-auditivo foi utilizada a Escala de Desvio Vocal (EDV) para verificar o grau geral do desvio vocal. Avaliação acústica foi feita no software PRAAT e foram extraídos os parâmetros frequência fundamental (f0), jitter, shimmer, proporção harmônico -ruído (HNR), Cepstral Peak Prominence Smoothed (CPPS), Acoustic Voice Quality Index (AVQI) e Acoustic Breathiness Index (ABI). Para mensuração das medidas aerodinâmicas, o tempo de emissão foi extraído no programa Audacity. Para comparar os resultados utilizou-se o teste paramétrico t de Student para amostras dependentes na análise das variáveis com distribuição normal e o teste de Wilcoxon para variáveis com distribuição não normal. RESULTADOS: Não houve diferenças entre os resultados do JPA e das medidas acústicas, nos momentos pré e pós exercício inspiratório. Quanto às medidas aerodinâmicas foi possível observar aumento significativo no valor do TMF /s/ (p=0,008). CONCLUSÃO: Não houve modificação na qualidade vocal após o exercício inspiratório com incentivador e exercitador respiratório, porém foi observado aumento do TMF do fonema /s/ após a realização do exercício.

"Lombard Effect" and Voice Changes in Adductor Laryngeal Dystonia: A Pilot Study.

OBJECTIVES: The aim was to describe the acoustic, auditory-perceptive, and subjective voice changes under the Lombard effect (LE) in adductor laryngeal dystonia (AdLD) patients. METHODS: Subjective perception of vocal effort (OMNI Vocal Effort Scale OMNI-VES), Maximum Phonation Time (MPT), and the perceptual severity of dysphonia (GRBAS scale) were assessed in condition of stillness and under LE in 10 AdLD patients and in 10 patients with typical voice. Speakers were asked to produce the sustained vowel /a/ and to read a phonetically balanced text aloud. Using the PRAAT software, the following acoustic parameters were analyzed: Mean Pitch (Hz), Minimum and Maximum Intensity (dB), the Fraction of Locally Unvoiced Frames, the Number of Voice Breaks, the Degree of Voice Breaks (%), the Cepstral Peak Prominence-Smoothed (CPPS) (dB). RESULTS: Under LE, the AdLD group showed a decrease of both G and S parameters of GRBAS and subjective effort, mean MPT increased significantly; in the controls there were no significant changes. In both groups under LE, pitch and intensity of the sustained vowel /a/ significantly increased consistently with LE. In the AdLD group the mean gain of OMNI-VES score and the mean gain of each parameter of the speech analysis were significantly greater than the controls' ones. CONCLUSION: Auditory feedback deprivation obtained under LE improves subjective, perceptual-auditory, and acoustics parameters of AdLD patients. These findings encourage further research to provide new knowledge into the role of the auditory system in the pathogenesis of AdLD and to develop new therapeutic strategies. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3754-3760, 2024.

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

PURPOSE: Literature suggests a dependency of the acoustic metrics, smoothed cepstral peak prominence (CPPS) and harmonics-to-noise ratio (HNR), on human voice loudness and fundamental frequency (F0). Even though this has been explained with different oscillatory patterns of the vocal folds, so far, it has not been specifically investigated. In the present work, the influence of three elicitation levels, calibrated sound pressure level (SPL), F0 and vowel on the electroglottographic (EGG) and time-differentiated EGG (dEGG) metrics hybrid open quotient (OQ), dEGG OQ and peak dEGG, as well as on the acoustic metrics CPPS and HNR, was examined, and their suitability for voice assessment was evaluated. METHOD: In a retrospective study, 29 women with a mean age of 25 years (± 8.9, range: 18-53) diagnosed with structural vocal fold pathologies were examined before and after voice therapy or phonosurgery. Both acoustic and EGG signals were recorded simultaneously during the phonation of the sustained vowels /ɑ/, /i/, and /u/ at three elicited levels of loudness (soft/comfortable/loud) and unconstrained F0 conditions. RESULTS: A linear mixed-model analysis showed a significant effect of elicitation effort levels on peak dEGG, HNR, and CPPS (all p < .01). Calibrated SPL significantly influenced HNR and CPPS (both p < .01). Furthermore, F0 had a significant effect on peak dEGG and CPPS (p < .0001). All metrics showed significant changes with regard to vowel (all p < .05). However, the treatment had no effect on the examined metrics, regardless of the treatment type (surgery vs. voice therapy). CONCLUSIONS: The value of the investigated metrics for voice assessment purposes when sampled without sufficient control of SPL and F0 is limited, in that they are significantly influenced by the phonatory context, be it speech or elicited sustained vowels. Future studies should explore the diagnostic value of new data collation approaches such as voice mapping, which take SPL and F0 effects into account.

Outcomes of laryngeal framework surgeries for unilateral vocal cord paralysis in the elderly patients.

OBJECTIVE: Laryngeal framework surgery is a widely accepted treatment for unilateral vocal fold paralysis with good functional outcomes. Recently, with the aging of the population, opportunities to perform this procedure in elderly patients have increased; however, the safety and efficacy of this procedure in elderly patients has not been established. Therefore, this study aimed to investigate the safety and functional outcomes of laryngeal framework surgery in elderly patients. METHODS: Between January 2008 and December 2017, 97 patients with unilateral vocal fold paralysis underwent laryngeal framework surgery, and 71 among them completed pre- and post-operative voice function evaluations. The clinical course of these 71 patients were retrospectively reviewed. RESULTS: Out of 71 patients, 35 were assigned to the younger group (< 65 years) and 36 to the elderly group (≥ 65 years). Complications included post-operative edema and submucosal hematoma that were safely managed in all cases, and no differences were identified between the groups. Significant improvements were observed in maximum phonation time (MPT), mean flow rate, alternating current/direct current ratio, pitch perturbation quotient, amplitude perturbation quotient, and noise-to-harmonic ratio in both groups, and multivariate analysis of variance revealed greater improvement in the younger group in MPT. CONCLUSION: Laryngeal framework surgeries for unilateral vocal fold paralysis are safe and effective, regardless of age. Better improvement was observed in the younger group in the MPT suggesting that the effects of laryngeal framework surgeries is more likely to be present in the younger group than in the elderly.

Effect of physical frailty on maximum phonation time in community-dwelling older individuals who visited a neurology outpatient clinic.

BACKGROUND: Maximum phonation time (MPT) is used to assess speech and other oral rehabilitation-related issues. Various factors contribute to MPT decline in older individuals. Although the impact of physical frailty on MPT has been suggested, this has not been conclusively determined. OBJECTIVE: To examine the relationship between MPT and physical frailty in community-dwelling individuals aged ≥60 years who were independently mobile. MPT-associated factors were investigated. METHODS: This cross-sectional study analysed the clinical data of 122 patients (age [interquartile range]: 80.0 [74.0-83.0] years) without dementia who visited a neurology department between 1 February 2021 and 31 January 2023. Investigated factors included age, sex, weight, height, body mass index, smoking history, grip strength, functional independence measure, vital capacity, oral diadochokinesis, MPT and the Japanese Cardiovascular Health Study score. Physical frailty was assessed based on the total score from five items (weight loss, weakness, exhaustion, slowness and low physical activity). The relationship between MPT and physical frailty was examined using Spearman's rank correlation coefficient and hierarchical multiple regression analysis. RESULTS: The MPT was negatively correlated with age (r = -0.347, p < .01) and physical frailty (r = -0.681, p < .01) and positively correlated with vital capacity (r = 0.474, p < .01) and height (r = 0.248, p < .01). The hierarchical multiple regression analysis, conducted with MPT as the dependent variable, demonstrated that physical frailty (ß = -.59, 95% confidence interval: -0.74 to 0.43, p < .001) had a strong influence on MPT. CONCLUSION: In older individuals, MPT is associated with physical frailty. When assessing MPT in clinical settings, it is advisable to perform a concurrent assessment of physical frailty.

Extrinsic Laryngeal Muscle Activity With Different Diameters and Water Depths in a Semi-Occluded Vocal Tract Exercise.

PURPOSE: Surface electromyography (sEMG) has been used to evaluate extrinsic laryngeal muscle activity during swallowing and phonation. In the current study, sEMG amplitudes were measured from the infrahyoid and suprahyoid muscles during phonation through a tube submerged in water. METHOD: The sEMG amplitude values measured from the extrinsic laryngeal muscles and the electroglottographic contact quotient (CQ) were obtained simultaneously from 62 healthy participants (31 men, 31 women) during phonation through a tube at six different depths (2, 4, 7, 10, 15, and 20 cm) while using two tubes with different diameters (1 and 0.5 cm). RESULTS: With increasing depth, the sEMG amplitude for the suprahyoid muscles increased in men and women. However, sEMG amplitudes for the infrahyoid muscles increased significantly only in men. Tube diameter had a significant effect on the suprahyoid sEMG amplitudes only for men, with higher sEMG amplitudes when phonating with a 1.0-cm tube. CQ values increased with submerged depth for both men and women. Tube diameter affected results such than CQ values were higher for men when using the wider tube and for women with the narrower tube. CONCLUSIONS: Vocal fold vibratory patterns changed with the depth of tube submersion in water for both men and women, but the patterns of muscle activation differed between the sexes. This suggests that men and women use different strategies when confronted with increased intraoral pressure during semi-occluded vocal tract exercises. In this study, sEMG provided insight into the mechanism for differences between vocally normal individuals and could help detect compensatory muscle activation during tube phonation in water for people with voice disorders.

Modification of velopharyngeal closure pressures during phonation by neuromuscular electrical stimulation in healthy individuals.

Introduction: Rhinophonia aperta may result from velopharyngeal insufficiency. Neuromuscular electrical stimulation (NMES) has been discussed in the context of muscle strengthening. The aim of this study was to evaluate in healthy subjects whether NMES can change the velopharyngeal closure pattern during phonation and increase muscle strength. Method: Eleven healthy adult volunteers (21-57 years) were included. Pressure profiles were measured by high resolution manometry (HRM): isolated sustained articulation of /a/ over 5 s (protocol 1), isolated NMES applied to soft palate above motor threshold (protocol 2) and combined articulation with NMES (protocol 3). Mean activation pressures (MeanAct), maximum pressures (Max), Area under curve (AUC) and type of velum reactions were compared. A statistical comparison of mean values of protocol 1 versus protocol 3 was carried out using the Wilcoxon signed rank test. Ordinally scaled parameters were analyzed by cross table. Results: MeanAct values measured: 17.15±20.69 mmHg (protocol 1), 34.59±25.75 mmHg (protocol 3) on average, Max: 37.86±49.17 mmHg (protocol 1), 87.24±59.53 mmHg (protocol 3) and AUC: 17.06±20.70 mmHg.s (protocol 1), 33.76±23.81 mmHg.s (protocol 3). Protocol 2 produced velum reactions on 32 occasions. These presented with MeanAct values of 13.58±12.40 mmHg, Max values of 56.14±53.14 mmHg and AUC values of 13.84±12.78 mmHg.s on average. Statistical analysis comparing protocol 1 and 3 showed more positive ranks for MeanAct, Max and AUC. This difference reached statistical significance (p=0.026) for maximum pressure values. Conclusions: NMES in combination with articulation results in a change of the velopharyngeal closure pattern with a pressure increase of around 200% in healthy individuals. This might be of therapeutic benefit for patients with velopharyngeal insufficiency.

The Thyrohyoid Muscle: A Crucial Player in Deglutition and Vocalization / El Músculo Tirohioideo: Un Actor Crucial en la Deglución y la Vocalización

SUMMARY: The thyrohyoid muscle is one of the four infrahyoid muscles. Its role in vocalization and deglutition could be often overlooked, despite its crucial participation in these processes. Unlike other infrahyoid muscles, the thyrohyoid muscle receives innervation from the first cervical spinal nerves which contributes to its unique function. Its primary action involves hyolaryngeal elevation during swallowing, contributing to the opening of the upper esophageal sphincter. In conjunction with other muscles, it also protects the airway and facilitates the passage of food into the esophagus. Variations in the muscle's thickness may exist, and its function can be influenced by chewing habits. Weakened muscles involved in swallowing are often associated with dysphagia, a common complication in stroke and brain-injured patients. Advanced imaging techniques and sleep studies have provided insights into the dynamics and frequency of swallowing. This review explores the anatomic structures, function in action, diagnosis and clinical implications of this muscle. Overall, understanding the significance of the thyrohyoid muscle enhances our comprehension of the intricate interplay of laryngeal muscles during vocalization and deglutition.

El músculo tirohioideo es uno de los cuatro músculos infrahioideos. A menudo podría pasarse por alto su papel en la vocalización y la deglución, a pesar de su participación crucial en estos procesos. A diferencia de otros músculos infrahioideos, el músculo tirohioideo recibe inervación de los primeros nervios espinales cervicales, lo que contribuye a su función única. Su acción principal implica la elevación hiolaríngea durante la deglución, contribuyendo a la apertura del esfínter esofágico superior. Junto con otros músculos, también protege las vías respiratorias y facilita el paso de los alimentos al esófago. Pueden existir variaciones en el grosor del músculo y su función puede verse influenciada por los hábitos de masticación. Los músculos debilitados involucrados en la deglución a menudo se asocian con disfagia, una complicación común en pacientes con accidente cerebrovascular y lesión cerebral. Las técnicas de imagen avanzadas y los estudios del sueño han proporcionado información sobre la dinámica y la frecuencia de la deglución. Esta revisión explora las estructuras anatómicas, la función en acción, el diagnóstico y las implicaciones clínicas de este músculo. En general, comprender la importancia del músculo tirohioideo mejora nuestra comprensión de la intrincada interacción de los músculos laríngeos durante la vocalización y la deglución.

Analyzing Vocal Fold Frequency Dynamics Using High-Speed 3D Laser Video Endoscopy.

OBJECTIVE: To examine changes in lateral and vertical vibratory motion along the anterior, middle, and posterior sections of the vocal folds, as a function of vocal frequency variations. METHODS: Absolute measurements of vocal fold surface dynamics from high-speed videoendoscopy with custom laser endoscope were made on 23 vocally healthy adults during sustained /i:/ production at 10%, 20%, and 80% of pitch range. The 3D parameters of amplitude (mm), maximum velocity opening/closing (mm/s), and mean velocity opening/closing (mm/s) were computed for the lateral and vertical vibratory motion along the anterior, middle, and posterior sections of the vocal folds. Linear mixed model analysis was conducted to evaluate the differences in (a) vocal frequency levels (high vs. normal vs. low pitch), (b) axis level (vertical vs. lateral), (c) position level (anterior vs. middle vs. posterior), and (d) gender differences (male vs. female). RESULTS: Overall, the superior surface vertical motion of the vocal fold is greater compared with the lateral motion, especially in males. Along the superior surface, the mean and maximum closing velocities are greater posteriorly for low pitch. The location (anterior, middle, and posterior) along the superior surface is relevant only for vocal fold closing rather than opening, as the dynamics are different along the various locations. CONCLUSIONS: The study highlights the significance of assessing the vertical motion of the superior surface of the vocal fold to understand the complex dynamics of voice production. LEVEL OF EVIDENCE: NA Laryngoscope, 134:3267-3276, 2024.

Ansa Cervicalis External Branch Anastomosis to Restore High Tone Voice in Thyroid Surgery.

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.

Therapeutic Singing and Semi-Occluded Vocal Tract Exercises for Individuals with Parkinson's Disease: A Randomized Controlled Trial of a Single Session Intervention.

Individuals with Parkinson's disease (PD) experience speech and voice-related symptoms that diminish communication and quality of life. Semi-occluded vocal tract (SOVT) exercises are targeted interventions that, when combined with the positive psychosocial benefits of therapeutic group singing (TGS), may affect outcomes. The purpose of this study was to explore the effectiveness of SOVT exercises, specifically straw phonation combined with TGS, to improve voice quality and mood for individuals with PD. We used a true experimental pretest-posttest between-subjects design (i.e., randomized controlled trial) facilitated by a board-certified music therapist. All participants (N = 27) were randomly assigned to one of three groups (a) straw phonation combined with TGS (SP + TGS, n = 10), (b) TGS (n = 10), and (c) speaking-only control group (n = 7). Participants completed voice recordings for acoustic measures and the Visual Analogue Mood Scale for mood analysis before and after a 30-min intervention. The results demonstrated significant improvement in voice quality evidenced by decreasing Acoustic Voice Quality Index scores following a single session for both SP + TGS and TGS intervention groups when compared to the control. Happiness scores improved in the experimental groups when compared to control. Although not statistically significant, participants in the experimental groups (SP + TGS, TGS) demonstrated better mean mood scores on happiness, anxiety, and angry when compared to control, indicating a positive psychological response to the singing interventions. Overall, this study indicated the effectiveness of SP + TGS and TGS as promising therapeutic interventions for voice quality and mood in individuals with PD.

Brainstem control of vocalization and its coordination with respiration.

Phonation critically depends on precise controls of laryngeal muscles in coordination with ongoing respiration. However, the neural mechanisms governing these processes remain unclear. We identified excitatory vocalization-specific laryngeal premotor neurons located in the retroambiguus nucleus (RAmVOC) in adult mice as being both necessary and sufficient for driving vocal cord closure and eliciting mouse ultrasonic vocalizations (USVs). The duration of RAmVOC activation can determine the lengths of both USV syllables and concurrent expiration periods, with the impact of RAmVOC activation depending on respiration phases. RAmVOC neurons receive inhibition from the preBötzinger complex, and inspiration needs override RAmVOC-mediated vocal cord closure. Ablating inhibitory synapses in RAmVOC neurons compromised this inspiration gating of laryngeal adduction, resulting in discoordination of vocalization with respiration. Our study reveals the circuits for vocal production and vocal-respiratory coordination.

Zoom in: factors affecting vocal habits during online meetings, a prospective trial on 40 subjects.

PURPOSE: To identify factors that influence vocal habits during online meetings (OMs). METHODS: A prospective trial of forty participants without any known hearing or vocal cord disorders. Subjects participated in an OM divided into six randomly ordered sections, with alterations in audio/speaking equipment and language: the computer's speaker-microphone, a single earbud, two-earbuds or headphones; with/without video, native-language-speaking (Hebrew) versus second language-speaking (English). Each section included free speech, sustained phonation, and a standardized passage. Participants ranked their vocal-effort for each section. Three blinded raters independently scored the voice using the GRBAS scale, and acoustic analyses were performed. RESULTS: No significant difference in self-reported vocal effort was demonstrated between sections. Second-language speaking resulted in significantly increased intensity (p < 0.0001), frequency (p = 0.015), GRBAS (p = 0.008), and strain (p < 0.0001) scores. Using the computer's speaker/microphone resulted in significantly higher strain (p < 0.0001). Using headphones, single or two earbuds resulted in lower intensity and a lower strain score. No differences were detected between OMs with or without video. CONCLUSIONS: Using the computer's microphone/speaker or speaking in a second language during OMs, may result in vocal habits associated with vocal trauma.