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

Period-doubled phonation, henceforth, period doubling, characterized by voicing periods that alternate in amplitudes and/or frequencies, is often perceived rough and with an indeterminate pitch. Lower pitch percept has been suggested by past studies when the degree of amplitude or frequency modulation increases. However, how listeners use period doubling when identifying linguistic tones remains unclear. The current study uses tasks of categorization with training, followed by imitation of tones manipulated with period doubling (with amplitude and frequency modulation, both separately and jointly) in a novel language. Native Mandarin and English speakers with different levels of music experience were tested. I show that period doubling leads to a low-tone bias in perception and imitation, especially as the modulation degree, particularly that of frequency, increases. Interestingly, interactions with stimulus f0 and modulation type show that in amplitude-modulated tokens, when compared to lower f0 (200 Hz), higher f0 (300 Hz) drives more low-tone responses. Period doubling is also imitated with lowered f0 and creaky quality. Language and music experience does not affect perceptual and imitative responses, suggesting that the perception of period doubling is not language-specific or conditioned by tonal knowledge. Period doubling likely signals low tones, even when the original f0 is high.

UNASSIGNED: Recurrent laryngeal nerve palsy is a rare but important complication after endarterectomy (CEA). The impact on voice quality after this procedure is also important. The aim of the study was to assess voice quality and vocal cord function after CEA.
UNASSIGNED: 200 patients were enrolled in the study. Inclusion criteria were indications for CEA and patient consent to the procedure. Endoscopic examination of the larynx was performed before the procedure, immediately after the procedure, on the 2nd day after the procedure, then 3 month and 6 months after the procedure. Voice was assessed by maximum phonation time (MPT), GRBAS scale, Voice Handicap Index (VHI) and the Voice-Related Quality of Life (V-RQOL) questionnaire.
UNASSIGNED: In the study group, the results on the GRBAS scale were significantly worse and the average MPT was shorter compared to the control group. In the V-RQOL assessment, patients rated their voice as fair or good, significantly more often noticed that they had difficulty speaking loudly and being heard, and that they felt short of air when speaking. In VHI-30, the total score was significantly higher in the study group compared to the control group. Voice disorders after the procedure were reported by 68 patients, while a disorder of the recurrent laryngeal nerve was observed immediately after the procedure in 32 patients. Most vocal cord disorders were transient. Ultimately, 3% of patients were diagnosed with vocal cord paralysis.
UNASSIGNED: Cranial nerves paralysis, including the recurrent laryngeal nerve, are a common complication after CEA. Majority the paralysis is transient, but requires appropriate diagnostic and therapeutic procedures. Vocal cord evaluation is a non-invasive and widely available examination and should be performed pre- and postoperatively after all neck surgeries. The incidence of voice disorders after CEA significantly affects the quality of life of patients and requires voice rehabilitation and patient care with psychological support.

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.

Many voice disorders are linked to imbalanced muscle activity and known to exhibit asymmetric vocal fold vibration. However, the relation between imbalanced muscle activation and asymmetric vocal fold vibration is not well understood. This study introduces an asymmetric triangular body-cover model of the vocal folds, controlled by the activation of bilateral intrinsic laryngeal muscles, to investigate the effects of muscle imbalance on vocal fold oscillation. Various scenarios were considered, encompassing imbalance in individual muscles and muscle pairs, as well as accounting for asymmetry in lumped element parameters. Measurements of amplitude and phase asymmetries were employed to match the oscillatory behavior of two pathological cases: unilateral paralysis and muscle tension dysphonia. The resulting simulations exhibit muscle imbalance consistent with expectations in the composition of these voice disorders, yielding asymmetries exceeding 30% for paralysis and below 5% for dysphonia. This underscores the relevance of muscle imbalance in representing phonatory scenarios and its potential for characterizing asymmetry in vocal fold vibration.

Voice quality has been defined variously in the literature ranging from states or postures of the glottis and vocal tract in general most broadly, to a narrower definition which refers to characteristics of vocal fold vibration during voiced phonation. Linguists have traditionally broken the voicing continuum into five basic categories based on roles they play in a language\'s phonology: (spread) voiceless, breathy, modal, creaky, (constricted) voiceless. Of these, the three central states, breathy, modal, creaky, are relevant to voice quality as discussed in this work. Voice qualities can be modelled as an interaction between subglottal pressure, degree of vocal fold approximation (aperture), longitudinal tension of the vocal folds (stiffness), and medial compression of the vocal folds (thickness). Breathy voicing is achieved with high glottal aperture, low stiffness, and low thickness, resulting in noise, low pitch, and increased spectral tilt. Creaky voicing has differing realizations depending on its linguistic role, prototypical creaky voice has low aperture, low stiffness, and high thickness, resulting in irregular and lower pitch, and decreased spectral tilt. Several other types of creaky voice quality exist including: 1) glottal fry, 2) multiply pulsed voice, and 3) nonconstricted creak. In this paper, we focus on creaky voice broadly-defined and concentrate on its distribution in North American English. While not contrastive, it plays an important role in phonology and a wide variety of other discourse, pragmatic, and social functions. In this context we present some of our current research into segmental and social factors relating to creaky voicing. We find a correlation between vowel height and creaky voicing. We also find evidence that voice quality is used by men to index gender in conversational speech. Our findings bear on the debate about the sociolinguistic uses of voice quality.
La qualité de voix a été définie de multiples façons dans la littérature spécialisée. Certains l’identifient, de manière très générale, aux diverses configurations de la glotte et de l’appareil phonatoire, alors que d’autres la restreignent aux modes de vibration des replis vocaux lors des épisodes de phonation voisée. Les linguistes considèrent traditionnellement que le continuum de la phonation recouvre cinq catégories principales, définies en fonction du rôle qu’elles remplissent dans la phonologie des langues du monde : la phonation nulle avec replis vocaux écartés, la voix soufflée, la voix modale, la voix craquée et la phonation nulle avec replis vocaux resserrés. Parmi ces cinq catégories, les trois états centraux : la voix soufflée, la voix modale et la voix craquée relèvent du domaine de la qualité de voix telle que traitée dans cet article. Les différentes qualités de voix peuvent se modéliser selon une interaction entre pression subglottique et degré d’ouverture, tension longitudinale et compression médiane des replis vocaux. La voix soufflée est produite en conférant un haut degré d’ouverture, un faible degré de tension longitudinale et un faible degré de compression médiane aux replis vocaux. La conjonction de ces ajustements engendre un bruit de friction, des fréquences basses et une élévation de l’inclinaison spectrale. La voix craquée se décline en diverses variétés en fonction de la fonction qu’elle remplit sur le plan linguistique. La voix craquée prototypique se définit par un faible degré d’ouverture des replis vocaux, un faible degré de tension longitudinale et un haut degré de compression médiane. La combinaison de ces ajustements résulte en des fréquences basses et irrégulières ainsi qu’en un abaissement de l’inclinaison spectrale. Il existe plusieurs autres types de voix craquées, au nombre desquels : 1) la « friture » glottique (glottal fry), 2) la voix pulsée (multiply pulsed voice) et 3) le craquement sans constriction (nonconstricted creak). Dans cet article, nous nous concentrons sur la voix craquée définie dans son acception la plus large et nous intéressons à sa distribution en anglais nord-américain. Bien que la voix craquée ne possède pas un statut contrastif, elle joue un rôle prépondérant en phonologie et remplit une gamme étendue de fonctions sociales, discursives et pragmatiques. C’est dans cette perspective que nous présentons une partie de l’état actuel de notre recherche sur les facteurs sociaux et les caractéristiques segmentales corrélés à la production de la voix craquée. Nous mettons ainsi en lumière le rapport observé entre hauteur des voyelles et usage de la voix craquée ainsi que certains éléments empiriques indiquant que les locuteurs hommes utilisent la qualité de voix pour marquer leur masculinité. Ces résultats sont de nature à enrichir le débat sur les fonctions sociolinguistiques de la qualité de voix.

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.

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

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.

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.