We know very little about how muscles and motor units in one region of the upper airway are impacted by adjustments in an adjacent airway region. In this case, the focus is on regulation of the expiratory airstream by the larynx and how changes in laryngeal aperture impact muscle motor unit activities downstream in the pharynx. We selected sound production as a framework for study as it requires (i) sustained expiratory airflow, (ii) laryngeal airway regulation for production of whisper and voice, and (iii) pharyngeal airway regulation for production of different vowel sounds. We used these features as the means of manipulating expiratory airflow, pharyngeal, and laryngeal airway opening to compare the effect of each on the activation of genioglossus (GG) muscle motor units in the pharynx. We show that some GG muscle motor units (a) discharge stably on expiration associated with production of vowel sounds, (b) are exquisitely sensitive to subtle alterations in laryngeal airflow, and (c) discharge at higher firing rates in high flow vs. low flow conditions even when producing the same vowel sound. Our results reveal subtle changes in GG motor unit discharge rates that correlate with changes imposed at the larynx, and which may contribute to the regulation of the expiratory airstream.

Un effort phonatoire intense ou prolongé peut causer des lésions des plis vocaux et une dysphonie. L’effort correspond à la perception, par un individu, de la force qu’il déploie pour réaliser une activité, ici la phonation visant à faire vibrer périodiquement les plis vocaux pour produire la voix dans la parole. L’évaluation de cet effort doit donc reposer, au moins, sur deux mesures, l’une perceptive et l’autre physique. Pour développer de telles mesures, il est nécessaire de dissocier l’effort phonatoire de la dysphonie, d’une part, et de l’effort articulatoire, d’autre part. Nous avons réalisé des expériences chez un grand nombre de sujets sains, en faisant varier l’effort phonatoire. Nous avons comparé les consonnes voisées et non voisées, ainsi que la parole vocale modale usuelle et non usuelle, c’est-à-dire différant par l’intensité, la hauteur et la qualité de la voix. Nous avons testé une mesure d’auto-perception de l’effort dans des comparaisons de syllabes par paires : le taux de difficulté ressenti pendant la production des consonnes voisées, par rapport aux non voisées. Le score moyen s’élevait à 22 sur 36, soit 61 pourcents. Nous avons aussi adapté une mesure acoustique de l’effort phonatoire : la fréquence fondamentale relative (RFFa). Les valeurs de RFFa, notamment à l’initiation de la voyelle post-consonantique, étaient plus basses, indiquant un effort plus important, pour les consonnes voisées que pour les non voisées et pour la voix forte-aigüe-pressée que pour la voix usuelle. Ces valeurs étaient cohérentes avec les mesures aérodynamiques réalisées. Nous avons également appliqué les deux mesures développées à des patients, dont nous présentons les cas. / An intense or prolonged phonatory effort can induce vocal fold lesions and dysphonia. The effort corresponds to the perception, by an individual, of the exertion to perform an activity, here the phonation aiming to create a periodic vibration the vocal folds in order to produce the voice during speech. Therefore, the evaluation of phonatory effort must rely, at least, on two measures, one perceptive and another physical. To develop such measures, it is necessary to dissociate phonatory effort from dysphonia, on the one hand, and from articulatory effort, on the other hand. We have conducted experiments in a large number of healthy subjects, by varying the phonatory effort. We compared voiced and voiceless consonants, as well as usual and unusual modal vocal speech, the last one differing in intensity, pitch, and voice quality. We tested a self-perception measurement in pair comparisons of syllables: the rate of difficulty felt during the production of the voiced consonants, compared to voiceless ones. The average score was 22 out of 36, or 61 percents. We also adapted an acoustic measure of phonatory effort: the relative fundamental frequency (RFFa). The values of RFFa, especially at the initiation of post-consonantal vowels, were lower, indicating a greater effort, for the voiced consonants than for the voiceless ones, and for the loud-high-pressed voice than for the usual voice. These values were consistent with the aerodynamic measurements we made. We also applied the two developed measures to patients and we presented their cases.

This thesis is part of a larger series of studies being conducted by Kristine Tanner, PhD, Associate Professor in the Department of Communication Disorders at Brigham Young University (BYU). The larger project is funded by the National Institute on Deafness and Other Communication Disorders at the National Institutes of Health. This thesis primarily investigated the effects of combination inhaled corticosteroids (ICs) on aerodynamic measures of the voice. In recent years, an increase in the localized laryngeal side effects from IC treatment, including dysphonia, have been reported. This study employed a between-groups experimental design, with two groups of rabbit larynges having been exposed to either ICs or nebulized isotonic saline two times each day for eight weeks at The University of Utah. For this study, the independent variable is group condition (i.e., IC versus saline) and the dependent variables are two aerodynamic measurements made at the onset of phonation using a benchtop experimental setup, namely phonation threshold pressure (PTP; cmH2O) and phonation threshold flow (PTF; L/min). The results of this study indicate a significant difference in PTP and PTF between vocal folds treated with IC as compared to vocal folds treated with nebulized isotonic saline solution. Implications of this study suggest negative changes in the voice due to IC treatment.

Although combination inhaled corticosteroids (ICs) are known to cause voice disorders in otherwise vocally healthy individuals, it is unknown whether those adverse effects can be reversed by the cessation of treatment. Quantitative aerodynamic measures such as phonation threshold pressure (PTP) and phonation threshold flow (PTF) can be used to identify the development of, and recovery from, vocal pathologies. We examined the effects and reversibility of ICs on laryngeal aerodynamics. This study was a mid-project investigation as part of a larger ongoing project. The 18 larynges were from rabbits that received ICs, a control condition, or no treatment. Experimental group rabbits received ICs twice per day until inflammatory changes (e.g., erythema, edema) became visible through endoscopic observation. One experimental group (i.e., the induction group) received treatment until symptoms were observed and then larynges were harvested. The other experimental group (i.e., the reversibility group) had ICs withdrawn once visible changes were detected via endoscopy; larynges were harvested only after these changes no longer differed from baseline. Both experimental groups had corresponding control rabbits that received twice-daily nebulized saline and followed the same withdrawal and larynx harvest schedule. A final group received no treatment. During benchtop phonation trials, PTP and PTF values were determined. All data were analyzed using descriptive and parametric statistics. No significant between-group differences were observed. Descriptively, however, average PTP and PTF values for the reversibility group were lower than the induction group. Additionally, average PTP and PTF values for the reversibility group were slightly lower than the induction group. Both experimental groups had higher PTP and PTF values than the control larynges. The results of this study indicate a trend in recovery for larynges afforded a recovery period from ICs. Further testing is needed to substantiate these preliminary findings.

O objetivo do presente trabalho foi analisar por meio da videolaringoscopia de alta velocidade o padrão vibratório das pregas vocais de indivíduos com e sem nódulo de prega vocal. Além disso, comparar o padrão vibratório das pregas vocais, de todos os grupos, analisado pela videolaringoscopia de alta velocidade com os resultados das análises acústica e quimográfica. Participaram deste estudo 36 indivíduos, do gênero feminino, com idades entre 18 e 45 anos, divididos em 3 grupos: grupo controle (GC), com 18 mulheres sem lesão nas pregas vocais e com vozes normais, grupo com nódulo vocal incipiente (GNI) com 8 mulheres com nódulo vocal incipiente e grupo com nódulo vocal (GN) composto por 10 mulheres com nódulo vocal de pequeno a grande. Procedimentos: gravação vocal, para análise acústica e perceptivo-auditiva, e exame laríngeo com a videolaringoscopia de alta velocidade para análise das imagens de alta velocidade (HSV) e da quimografia digital (DKG). Resultados: Encontraram-se tempos de fase do ciclo glótico semelhantes entre o grupo controle e o grupo com nódulo vocal incipiente, no entanto, significativamente menores do que os tempos de fase dos indivíduos com nódulo vocal, com exceção do tempo de fechamento. Observou-se também diferenças para o quociente de abertura (OQ), no grupo com nódulo vocal a proporção em que a prega vocal ficou aberta em um ciclo foi significativamente maior do que no grupo sem nódulo (OQ = 0,81 ± 0,07 e OQ = 0,68 ± 0,12, respectivamente). Além disso, por meio da quimografia digital pode-se observar que a amplitude de vibração das pregas vocais foi significativamente reduzida no grupo com nódulo vocal em relação aos indivíduos sem nódulo. Discussão e Conclusão: Concluiu-se neste trabalho, por meio da análise da videolaringoscopia de alta velocidade, que o padrão de vibração das pregas vocais foi regular em todos os grupos analisados, apresentando variações mínimas em relação ao período e à amplitude. Na comparação dos grupos, observou-se que o grupo com nódulo vocal apresentou redução da amplitude de vibração das pregas vocais em relação ao grupo controle. Além disso, no grupo com nódulo vocal o quociente de abertura indicou predomínio do tempo de fase aberta. Na comparação das metodologias empregadas concluiu-se que a videolaringoscopia de alta velocidade e a quimografia digital avaliam de forma distinta os tempos de fase do ciclo vibratório, e, consequentemente o quociente de abertura das pregas vocais, cujo cálculo é baseado nestes tempos de fase. Estes resultados alertam a necessidade de estabelecerem-se valores diferentes para a normalidade entre a videolaringoscopia de alta velocidade e a quimografia digital. / This dissertation reports on the analysis of the vocal fold vibration pattern of subjects with and without vocal fold nodule by high-speed videoendoscopy. It also compares the pattern of vocal fold vibration in all groups analyzed with the results of acoustic and kymograph analyses. Thirty six women whose age ranged from 18 to 45 participated of the study. They were divided into 3 groups: control group (GC), with 18 women with no lesions on vocal folds; incipient vocal nodule group (GNI), composed of 8 women with incipient vocal nodule; and vocal nodule group (GN), composed of 10 women with a smallto-large vocal nodule. The procedures comprised voice recording for acoustic analysis and auditory-perceptual and highspeed videoendoscopy for high-speed image analysis and digital kymography (DKG). The results revealed phases of the vibration cycle (open phase, closed phase, opening phase and closing phase) similar to those of the control group and incipient vocal nodule group, but significantly lower than the phase times of the vibration cycle of vocal nodule group, except for the closing phase. Regarding the open quotient (OQ), in the group with vocal nodule the proportion at which the vocal fold was opened in a cycle was significantly higher than the control group (OQ = 0,81 ± 0,07 and OQ = 0,68 ± 0,12, respectively). The digital kymography allowed observing that the vibration amplitude of the vocal folds was significantly reduced in the group with vocal nodule in comparison to the control group. By means of the high-speed videoendoscopy analysis, it was possible to conclude that the pattern of vocal fold vibration was regular in all groups, with minor variations in the period and amplitude. By comparing the groups, the group with vocal nodule decreased the amplitude of vibration of the vocal folds in the control group. Moreover, in the group with vocal nodule the open quotient indicated predominance of the open phase. The comparison of the methodologies allowed concluding that high-speed videoendoscopy and digital kymography asses the time phase of the vibration cycle differently, and hence the open quotient the vocal folds, which is calculated based on these times of phase. The results emphasize the need to set up different values for the normality of high-speed videoendoscopy and digital kymography.

Diss. (sammanfattning) Stockholm : Karol. inst., 2001. / Härtill 6 uppsatser.

O objetivo do presente trabalho foi analisar por meio da videolaringoscopia de alta velocidade o padrão vibratório das pregas vocais de indivíduos com e sem nódulo de prega vocal. Além disso, comparar o padrão vibratório das pregas vocais, de todos os grupos, analisado pela videolaringoscopia de alta velocidade com os resultados das análises acústica e quimográfica. Participaram deste estudo 36 indivíduos, do gênero feminino, com idades entre 18 e 45 anos, divididos em 3 grupos: grupo controle (GC), com 18 mulheres sem lesão nas pregas vocais e com vozes normais, grupo com nódulo vocal incipiente (GNI) com 8 mulheres com nódulo vocal incipiente e grupo com nódulo vocal (GN) composto por 10 mulheres com nódulo vocal de pequeno a grande. Procedimentos: gravação vocal, para análise acústica e perceptivo-auditiva, e exame laríngeo com a videolaringoscopia de alta velocidade para análise das imagens de alta velocidade (HSV) e da quimografia digital (DKG). Resultados: Encontraram-se tempos de fase do ciclo glótico semelhantes entre o grupo controle e o grupo com nódulo vocal incipiente, no entanto, significativamente menores do que os tempos de fase dos indivíduos com nódulo vocal, com exceção do tempo de fechamento. Observou-se também diferenças para o quociente de abertura (OQ), no grupo com nódulo vocal a proporção em que a prega vocal ficou aberta em um ciclo foi significativamente maior do que no grupo sem nódulo (OQ = 0,81 ± 0,07 e OQ = 0,68 ± 0,12, respectivamente). Além disso, por meio da quimografia digital pode-se observar que a amplitude de vibração das pregas vocais foi significativamente reduzida no grupo com nódulo vocal em relação aos indivíduos sem nódulo. Discussão e Conclusão: Concluiu-se neste trabalho, por meio da análise da videolaringoscopia de alta velocidade, que o padrão de vibração das pregas vocais foi regular em todos os grupos analisados, apresentando variações mínimas em relação ao período e à amplitude. Na comparação dos grupos, observou-se que o grupo com nódulo vocal apresentou redução da amplitude de vibração das pregas vocais em relação ao grupo controle. Além disso, no grupo com nódulo vocal o quociente de abertura indicou predomínio do tempo de fase aberta. Na comparação das metodologias empregadas concluiu-se que a videolaringoscopia de alta velocidade e a quimografia digital avaliam de forma distinta os tempos de fase do ciclo vibratório, e, consequentemente o quociente de abertura das pregas vocais, cujo cálculo é baseado nestes tempos de fase. Estes resultados alertam a necessidade de estabelecerem-se valores diferentes para a normalidade entre a videolaringoscopia de alta velocidade e a quimografia digital. / This dissertation reports on the analysis of the vocal fold vibration pattern of subjects with and without vocal fold nodule by high-speed videoendoscopy. It also compares the pattern of vocal fold vibration in all groups analyzed with the results of acoustic and kymograph analyses. Thirty six women whose age ranged from 18 to 45 participated of the study. They were divided into 3 groups: control group (GC), with 18 women with no lesions on vocal folds; incipient vocal nodule group (GNI), composed of 8 women with incipient vocal nodule; and vocal nodule group (GN), composed of 10 women with a smallto-large vocal nodule. The procedures comprised voice recording for acoustic analysis and auditory-perceptual and highspeed videoendoscopy for high-speed image analysis and digital kymography (DKG). The results revealed phases of the vibration cycle (open phase, closed phase, opening phase and closing phase) similar to those of the control group and incipient vocal nodule group, but significantly lower than the phase times of the vibration cycle of vocal nodule group, except for the closing phase. Regarding the open quotient (OQ), in the group with vocal nodule the proportion at which the vocal fold was opened in a cycle was significantly higher than the control group (OQ = 0,81 ± 0,07 and OQ = 0,68 ± 0,12, respectively). The digital kymography allowed observing that the vibration amplitude of the vocal folds was significantly reduced in the group with vocal nodule in comparison to the control group. By means of the high-speed videoendoscopy analysis, it was possible to conclude that the pattern of vocal fold vibration was regular in all groups, with minor variations in the period and amplitude. By comparing the groups, the group with vocal nodule decreased the amplitude of vibration of the vocal folds in the control group. Moreover, in the group with vocal nodule the open quotient indicated predominance of the open phase. The comparison of the methodologies allowed concluding that high-speed videoendoscopy and digital kymography asses the time phase of the vibration cycle differently, and hence the open quotient the vocal folds, which is calculated based on these times of phase. The results emphasize the need to set up different values for the normality of high-speed videoendoscopy and digital kymography.

No description available.

No description available.

Animal models are used extensively in voice research to study aspects of phonation, including physiology, kinematics, structure, and histology. Animals such as dog, cow, pig, sheep, deer, monkey, ferret, and rabbit have been used in voice research, with pig being one of the most common models. It is thought that the pig larynx is highly similar to the human larynx and one of the best models used in animal translational research. As with any model, however, the pig larynx does have some limitations. Perhaps a limitation most important to the rationale of this investigation is that pigs are difficult animals to study in vivo. Maintenance for a pig is challenging due to its large size and the variability of phonation use in the animal. Therefore, viable and practical alternatives are needed for in vivo voice research. The current study collected preliminary normative data from an alternate animal model, the rabbit, which has been used more recently in studies to model human phonation. The rabbit model was chosen due to its histological similarities to humans, in vivo phonation patterns, size, and practicality. The rabbit represents a more practical model for some longitudinal designs, as well as ex vivo phonatory models with aerodynamic measures as the primary variables. The current study involved a comparison of two aerodynamic measures, specifically phonation threshold pressure (PTP) and phonation threshold flow (PTF) between two groups, pig and rabbit larynges. The purpose of this study was to determine normative aerodynamic values for rabbits and to compare these with normative values for pigs during excised larynx benchtop phonation. Each group consisted of 15 larynges that were finely dissected to reveal the true vocal folds. Each larynx was then connected to a pseudolung and humidified air was passed through it. Fifteen phonation trials were elicited and the results averaged for each larynx. The results indicated that PTP and PTF were significantly different between the two groups, with PTP and PTF being lower for the rabbit group. Additionally, PTP values for rabbits were closer than pigs to the typical human value; however, some methodological challenges to rabbit benchtop models, including size and structural integrity, also exist. But the results from this study indicate that rabbits should be considered a viable option for voice research that would be more feasible with a small animal option that translates well to humans than a large animal option.