The purpose of this study is to assemble information needed to assess, understand and hopefully correct muscular hyperfunction that is related to tongue tension in singing and speech which inhibit freely, efficiently, and comfortably produced beautiful singing. This text will include a definition of freely produced, fully resonating tone for beautiful singing, major components of vocal technique, physiology related to singing and speech production, hyperfunctions associated with tongue tension, tongue involvement in the articulation of the four major singing languages, and will present exercises for training the muscles of coordination in a manner conducive to singing and speech.

Laryngopharyngeal reflux (LPR) is currently one of the most prevalent conditions associated with voice disorders being treated in voice care centers worldwide. Many singers experience voice related disturbances but are unaware that these disturbances may be the result of LPR. The purpose of this study was to quantify the perceptual symptoms and objective measures of LPR in a population of singers in order to understand the relationship between perceived symptoms, laryngeal findings, and evidence of acid exposure to the larynx. The Reflux Symptom Index (RSI), Reflux Finding Score (RFS), and the Dx-pH monitoring system were used to quantify participant symptoms, endoscopic findings, and pH levels in the oropharynx. The population included 12 semi-professional and professional singers. Significant correlations were found between the RFS, RSI and pH mild and moderate pH levels. This indicates that singers are sensitive to even small deviations of pH and this should be taken into consideration when evaluating a singers who have suspected LPR. Due to the variety of etiologies that can produce the symptoms and physical findings mentioned in this study, it is imperative that more objective data be obtained to confirm the presence of reflux in the oropharynx. As such, endoscopic findings and symptoms alone are not a good indication of reflux exposure and more objective data, like an oropharyngeal pH measurement system, should be implemented to quantify reflux in the oropharynx. The RSI and the RFS are valid tools for qualifying perceptions and physical findings however they are not without flaws.

La cyclooxygénase-2 (COX-2) a été associée à un mauvais pronostic dans plusieurs cancers. L'objectif de cette étude est d'évaluer si la COX-2 est un facteur pronostique dans le cancer glottique. Cette étude a été effectuée sur des tissus de patients ayant participé à un essai clinique qui évaluait l'efficacité de l'alpha-tocophérol pour réduire la survenue de . seconds cancers primaires (SCP) chez des patients avec un cancer de la tête et du cou. Des analyses immunohistochimiques ont été effectuées sur les biopsies pré-traitement de 301 patients avec un cancer glottique de stade précoce traité par radiothérapie. Les rapports d'incidence (RI) et leurs intervalles de confiance à 95% (le) associés à une surexpression de COX-2 sont de 0,94 (le: 0,55-1,62) pour la récidive et de 1,57 (le: 1,01-2,45) pour la mortalité globale. Pour les SCP, les RI sont de 2,63 (IC : 1,32-5,23) pour les premières 3,5 années de suivi et de 0,55 (IC : 0,22-1,32) pour les 3,5 années subséquentes. En conclusion, la surexpresssion de laCOX-2 dans le cancer du larynx glottique est associée à une augmentation de .la mortalité globale et confère une augmentation du risque de SCP durant les 3,5 premières années de suivi. Des études subséquentes sont nécessaires pour expliquer les effets observés au niveau des SCP. L'expression de la COX-2 pourrait s'avérer utile pour prédire le pronostic d'un patient sur une base individuelle.

The larynx is the mammalian organ of vocalization. Humans have a degree of control over this organ considerably beyond the abilities of other primates, most notably in our control over the larynx during speech. Although there is an abundance of research on the neural basis of speech, relatively little of this research has focused on the control of the larynx. First, I performed a meta-analysis to search for brain areas responsible for making explicit judgments about affective prosody to identify candidate premotor areas in prefrontal cortex that may also plan the affective component of affective prosody (Chapter 2). The inferior frontal gyrus pars orbitalis was the only prefrontal region preferentially engaged by affective vocalizations. Second, I used functional magnetic resonance imaging to determine whether there are discrete neural systems for producing innate-affective versus arbitrary non-affective vocalizations in the human brain, as has been predicted from non-human primate models (Chapter 3). The vocal-motor system demonstrated a lack of specialization since both types of vocalizations engaged the entire network. Third, I searched for brain areas that were preferentially engaged during vocal imitation (Chapter 4), which is a key process in vocal learning. Vocal imitation preferentially engaged a cortico-striate network similar to that predicted from avian models of vocal imitation. Finally, I performed a meta-analysis to explore the neural basis of persistent developmental stuttering (Chapter 5), a speech disorder that is associated with poor control of the laryngeal muscles. Among other brain areas, primary motor regions controlling the larynx were abnormally activated in the brains of people who stutter. Together these studies advance our knowledge of the human vocal-motor system, how it relates to that in other species, and how this system may be disrupted in persistent developmental stuttering. I discuss remaining gaps in our knowledge that will be the focus of my future research. / Dissertation / Doctor of Philosophy (PhD) / One hallmark of the human species is our ability to talk. This dissertation describes a body of research that uses modern brain imaging technology ¬to study the brain systems that underlie this ability in humans –referred to as the vocal-motor system. It then compares this system in humans to the closest equivalent in monkeys, since monkeys lack this ability but share relatively recent common ancestry with humans. It also makes comparisons with the brains of songbirds, since the ability of juvenile songbirds to learn songs may share similarities with the human ability to learn speech. Finally, it looks at the potential dysfunction of this system in the brains of people who stutter.

No description available.

The movement and control of the vocal folds within the laryngeal cavity enables three crucial physiological functions: 1) allowing respiration by opening, 2) aiding in airway protection by closing, and 3) regulating sound production during phonation. Although treatment options have improved, many of the estimated 7.5 million individuals in the United States who are annually affected by voice-related disorders still face serious challenges related to dysphonia and dysphagia. The need for improved voice-disorder treatments has motivated the work presented in this dissertation which focuses on modeling and manufacturing the vocal folds and aims to answer three main questions: 1) what are the mechanical properties of the vocal folds and how do they change across the full vocal range? 2) how do those properties influence the dynamic behavior of the tissue? and 3) can we manufacture a synthetic vocal fold model that exhibits a desired and controllable dynamic behavior? First, the elastic properties of sixteen porcine vocal folds were evaluated through uniaxial tensile tests on a custom built experimental setup. Stress-strain data was analyzed using an optimization method to yield continuous model parameters which described the linear and nonlinear elastic regions as well as transition points between those regions. Next, the impact of the vocal fold elastic properties on the frequencies of vibration was evaluated through dynamic tests on excised porcine larynges. Sound data was analyzed via a spectrogram and through the use of fast Fourier transforms to study changes in the frequency of vibration while the vocal folds were stretched. Additionally, a mathematical aeroelastic model of phonation was implemented to further evaluate the changing elastic properties on vocal fold dynamics. Next, eight synthetic vocal fold models were created, each with varying mechanical properties and a geometry based on reported anatomical measurements of porcine vocal folds. The synthetic models were then dynamically tested to further study the impact of changes in mechanical properties on the dynamic behavior of the synthetic vocal folds. / Doctor of Philosophy / The movement and control of the vocal folds within the voice-box enables three crucial physiological functions: 1) allowing respiration by opening, 2) aiding in airway protection and swallowing by closing, and 3) regulating sound production during vocalization. Although treatment options have improved, many of the estimated 7.5 million individuals in the United States who are annually affected by voice-related disorders still face serious challenges related to speech production and swallowing which often results in significant detrimental impacts to quality of life. The need for improved treatments is most easily observed in the evaluation of treatment options following a total laryngectomy, which is a procedure where the entire voice-box is removed often due to cancer. Following a laryngectomy, all three of the vital functions of the vocal folds are immediately impacted as patients adjust to breathing through and protecting a redirected airway and are forced to use alternative methods of speech production which often result in monotone or robotic-sounding speech. The need for improved voice-disorder treatments has motivated the work presented in this dissertation which focuses on modeling and manufacturing the vocal folds and aims to answer three main questions: 1) what are the mechanical properties of the vocal folds? 2) how do those properties influence the dynamic behavior of the tissue during sound production? and 3) can we manufacture synthetic vocal folds that produce a desired and controllable dynamic behavior? Sixteen porcine vocal fold samples were mechanical tested to evaluate the elastic properties of the tissue. Next, porcine voice-box samples were experimentally tested in a way that simulated sound production by subjecting the samples to a heated and humidified air flow, similar to the air flow conditions coming out of the lungs. In this way, the relationship between the tissue properties and the frequencies of sound was investigated. Lastly, the synthetic vocal fold samples were evaluated using a similar experimental protocol to further investigate the impact of changing structural properties on the dynamics of the vocal folds during sound production.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.

Dans le cadre du développement d’un larynx artificiel, les expérimentations sur l’animal et les essais cliniques ont mis en évidence un défaut de ré-épithélialisation de la face endoluminale de la prothèse. Cet épithélium respiratoire est absolument nécessaire pour obtenir un dispositif implantable totalement intégré dans le corps mais également pour la fonctionnalité d’un tel implant. Dans ce travail nous avons développé de nouveaux films d’hydrogels de collagène et d’acide hyaluronique interpénétrés et réticulés pour assurer une repousse épithéliale rapide. Ces films d’hydrogels optimisés ont une résistance suffisante à l’hydrolyse pour limiter leur dégradation précoce une fois implantés. Ils ont été fonctionnalisés par des facteurs de croissance et de différenciation cellulaire libérés de façon progressive avec un résultat objectivé sur la prolifération cellulaire. L’encapsulation de cellules immunitaire et l’utilisation de cytokines dans ces gels permettent également de moduler la réponse inflammatoire vers un processus de cicatrisation plutôt que de rejet. / As part of the development of an artificial larynx, in vivo experiments and clinical trials have revealed a defect in re-epithelialization of the endoluminal side of the prosthesis. This respiratory epithelium is absolutely necessary to obtain an implantable device fully integrated into the body but also for the functionality of such an implant. In this work we have developed patches of interpenetrated and reticulated hydrogels based on collagen and hyaluronic acid to ensure rapid epithelial regrowth. These optimized hydrogel patches have sufficient resistance to hydrolysis to limit their early degradation once implanted. They have been functionalized by growth and cell differentiation factors that are released gradually with an objectified result on cell proliferation. Encapsulation of immune cells and the use of cytokines in these gels also modulate the inflammatory response towards a healing process rather than rejection.

The purpose of this study was to provide, through systematic investigation, empirical data to support or reject the assumption that auditory stimulation by discrete pitches evokes consistent muscle responses in the extrinsic laryngeal muscles. The study was an electromyographic investigation of specific upper and lower extrinsic laryngeal muscles as stimulated by two specific pitch stimuli. The responses were evoked by auditory stimulation, without vocalization. From these findings, it was concluded that a direct relationship exists between specific pitch stimuli and specific extrinsic laryngeal muscle responses. It was concluded that these responses likely exist in the general population.

The vocal tract shape is crucial to voice production. Its lower part seems particularly relevant for voice timbre. This study analyzes the detailed morphology of parts of the epilaryngeal tube and the hypopharynx for the sustained German vowels /a/, /e/, /i/, /o/, and /u/ by thirteen male singer subjects who were at the beginning of their academic singing studies. Analysis was based on two different phonatory conditions: a natural, speech-like phonation and a singing phonation, like in classical singing. 3D models of the vocal tract were derived from magnetic resonance imaging and compared with long-term average spectrum analysis of audio recordings from the same subjects. Comparison of singing to the speech-like phonation, which served as reference, showed significant adjustments of the lower vocal tract: an average lowering of the larynx by 8 mm and an increase of the hypopharyngeal cross-sectional area (+ 21.9%) and volume (+ 16.8%). Changes in the analyzed epilaryngeal portion of the vocal tract were not significant. Consequently, lower larynx-to-hypopharynx area and volume ratios were found in singing compared to the speech-like phonation. All evaluated measures of the lower vocal tract varied significantly with vowel quality. Acoustically, an increase of high frequency energy in singing correlated with a wider hypopharyngeal area. The findings offer an explanation how classical male singers might succeed in producing a voice timbre with increased high frequency energy, creating a singer‘s formant cluster.