Academic literature on the topic 'Laryngeal vibratory mechanisms'

The role of various sensory stimuli for stimulating swallowing in infants may be of importance for assisting infants to develop oral feeding. We evaluated the swallowing mechanism response to two devices for increasing the rate of nonnutritive swallowing in two typically developing infant age groups, ages 2–4 mo and 7–9 mo. One device was a pacifier familiar to the infant; the other was a small vibrator placed on the skin overlying the thyroid cartilage. The rate of nonnutritive swallowing while infants were awake was compared in three 10-min conditions: at rest without stimulation (spontaneous); during nonnutritive sucking with a pacifier; and over 10 min containing 18 epochs of vibratory stimulation for 10 s each. To assess whether vibration on the throat over the laryngeal area altered respiration, the mean cycle length was compared between 10-min intervals either containing vibratory stimulation or without stimulation at rest. Both the pacifier and laryngeal vibration stimulation doubled the rate of swallowing in the infants with a mean age of 3 mo 16 days and infants with a mean age of 8 mo 8 days. No differences occurred in the mean respiratory cycle length between intervals with and without vibration in either age group. Results suggest that nonnutritive sucking, vibration, or both might be beneficial in enhancing swallowing in young infants. Because vibration on the neck would not interfere with oral transfer of liquid, it might provide additional stimulation for swallowing during oral feeding. Both stimulation types should be evaluated for enhancing swallowing in infants with immature swallowing skills.

Abstract Background Anatomical and cognitive adaptations to overcome morpho-mechanical limitations of laryngeal sound production, where body size and the related vocal apparatus dimensions determine the fundamental frequency, increase vocal diversity across taxa. Elephants flexibly use laryngeal and trunk-based vocalizations to form a repertoire ranging from infrasonic rumbles to higher-pitched trumpets. Moreover, they are among the few evolutionarily distantly related animals (humans, pinnipeds, cetaceans, birds) capable of imitating species-atypical sounds. Yet, their vocal plasticity has so far not been related to functions within their natural communicative system, in part because not all call types have been systematically studied. Here, we reveal how Asian elephants (Elephas maximus) produce species-specific squeaks (F0 300–2300 Hz) by using acoustic camera recordings to visualize sound emission and examining this alongside acoustic, behavioral, and morphological data across seven captive groups. Results We found that squeaks were emitted through the closed mouth in synchrony with cheek depression and retraction of the labial angles. The simultaneous emission of squeaks with nasal snorts (biphonation) in one individual confirmed that squeak production was independent of nasal passage involvement and this implicated oral sound production. The squeaks’ spectral structure is incongruent with laryngeal sound production and aerodynamic whistles, pointing to tissue vibration as the sound source. Anatomical considerations suggest that the longitudinal closed lips function as the vibrators. Acoustic and temporal parameters exhibit high intra- and inter-individual variability that enables individual but no call-subtype classification. Only 19 of 56 study subjects were recorded to squeak, mostly during alarming contexts and social arousal but some also on command. Conclusion Our results strongly suggest that Asian elephants force air from the small oral cavity through the tensed lips, inducing self-sustained lip vibration. Besides human brass players, lip buzzing is not described elsewhere in the animal kingdom. Given the complexity of the proposed mechanism, the surprising absence of squeaking in most of the unrelated subjects and the indication for volitional control, we hypothesize that squeak production involves social learning. Our study offers new insights into how vocal and cognitive flexibility enables mammals to overcome size-related limitations of laryngeal sound production. This flexibility enables Asian elephants to exploit a frequency range spanning seven octaves within their communicative system.

L’objectif de cette thèse est d’évaluer les effets d’un travail principalement vocal en musicothérapie active sur les aspects relationnels d’enfants porteurs de Troubles du Spectre autistique (TSA). Il s’agit également de définir les modalités d’application les plus pertinentes et de dégager quelques principes pour le travail autour de la voix en musicothérapie avec ces enfants. Afin de circonscrire au mieux notre objet, nous nous appuyons sur divers champs disciplinaires tels que la musicothérapie, la psychologie développementale, la musicologie et l'ethnomusicologie, l'anthropologie, la phoniatrie, les neurosciences ou la psychanalyse. À partir d’une première étude exploratoire, nous avons élaboré des couplages gestuelle-voix (GLM) et tenté de repérer quelles en étaient les composantes les plus pertinentes pour générer l’intérêt des enfants. Nous avons gardé les couplages les plus efficients et les avons intégrés à un dispositif de musicothérapie axé sur la voix, les gestes et des jeux rythmiques. Notre étude principale a été réalisée à partir de matériel vidéo clinique recueilli dans le cadre des soins courants en musicothérapie sur une année scolaire. Elle concerne seize enfants porteurs de TSA, âgés de 2 à 8 ans, accueillis en hôpital de jour. À partir des films, nous évaluons les effets des séances de notre dispositif de musicothérapie sur l’évolution des comportements autistiques des enfants accueillis, grâce à la grille d’Évaluation des Comportements Autistiques (ECA-R, Barthélémy, Roux, Adrien et al., 1997). Nous comparons par ailleurs l'impact des propositions vocales associées à une gestuelle (GLM) à celui des activités rythmiques ou des comptines, concernant plus spécifiquement le regard, l’imitation et le partage émotionnel. Dans une troisième étude, nous évaluons les effets des couplages voix-geste sur un jeune enfant autiste non verbal en situation de musicothérapie active individuelle. Dans cette étude, nous réalisons une analyse de films vidéo recueillis dans le cadre des soins courants, et cherchons à évaluer l’évolution des manifestations vocales, des comportements d’approche spontanée et d’évitement de l’enfant. Notre quatrième étude s’intéresse à l’utilisation des couplages voix-geste auprès d’un enfant autiste non verbal et déficient visuel sévère en musicothérapie individuelle. À travers cette étude de cas, nous essayons de comprendre les processus que les couplages GLM permettraient de mettre à l’œuvre. L'ensemble de nos résultats soutiennent l’hypothèse que la voix associée à une co-modalité, telle qu’elle est présentée dans nos couplages GLM, présente un réel intérêt pour travailler la sphère relationnelle avec des enfants porteurs de TSA à partir d’une expérience vocale
The aim of this thesis is to evaluate the effects of a mainly vocal work in active music therapy on the relational aspects of children with Autism Spectrum Disorders (ASD). It is also a question of defining the most relevant modalities of application and to draw some principles for the work around voice in music therapy with these children. In order to best circumscribe our object, we rely on various disciplinary fields such as music therapy, developmental psychology, musicology and ethnomusicology, anthropology, phoniatrics, neurosciences or psychoanalysis. On a first exploratory study, we developed gesture-voice coupling (GLM) and tried to identify what were the most relevant components to generate the interest of children. At the end of this step, we found that the laryngeal mechanisms at work in the couplings could be a determining factor. We kept the most efficient couplings and integrated them into a device of music therapy focused on voice, gestures and rhythmic games. Our main study was based on clinical video material collected as part of the current care in music therapy program over a school year. It concerns sixteen children with ASD, aged 2 to 8 years, who were admitted to a day hospital. From the films, we evaluate the impact of the sessions of our music therapy device on the evolution of the autistic behaviors of the children, thanks to the Revised Behavior Summarized Evaluation Scale (BSE-R), (Barthélémy, Roux, Adrien et al., 1997). We also compare the impact of gesture-voice couplings (GLM) with that of rhythmic activities or nursery rhymes, more specifically concerning gaze, imitation and emotional sharing. In a third study, we evaluate the effects of voice-gesture coupling on a young non-verbal autistic child in a situation of individual active music therapy. In this study, we perform an analysis of video films collected as part of routine care, and seek to evaluate the evolution of vocal manifestations, spontaneous approach behaviors and avoidance of the child. Our fourth study focuses on the use of voice-gesture couplings in non-verbal autistic children with severe visual impairment in individual music therapy. Through this case study, we try to understand the processes that GLM couplings would put into action. Overall, our results support the hypothesis that voice associated with co-modality, as presented in our GLM couplings, is of real interest for working in the relational sphere with children with ASD