São freqüentes as queixas entre as mulheres, particularmente entre as cantoras, de que ocorrem alterações na voz após a menopausa. Há relatos na literatura de que a freqüência fundamental da voz da mulher se altera nesta fase da vida. Como a prega vocal possui receptores para os esteróides sexuais, é possível que essas alterações sejam decorrentes da deficiência estrogênica observada no climatério. O presente trabalho teve como objetivo comparar a freqüência fundamental da voz (F0) de mulheres na pós-menopausa usuárias e não usuárias de terapia de reposição hormonal (TRH) com mulheres no menacme. Foram estudadas 45 pacientes: grupo-controle (15 mulheres de 20 a 40 anos, não usuárias de anticoncepcional hormonal, não fumantes, com ciclos menstruais regulares), grupo com TRH (15 mulheres de 45 a 60 anos, menopausadas há mais de 2 anos, usuárias de valerato de estradiol 1mg/norgestimato 90 mcg há no mínimo 6 meses) e grupo sem TRH (15 mulheres com idade de 45 a 60 anos, menopausadas há mais de 2 anos sem TRH há no mínimo 6 meses). Todas as pacientes foram submetidas à avaliação otorrinolaringológica e videolaringoscopia para confirmar a integridade da laringe. Posteriormente, avaliou-se a F0 com a emissão das vogais “e” e “i” na altura de fala habitual da paciente. A F0 foi analisada através do programa Dr.Speech 3.0®. Foi utilizado o teste ANOVA para comparação das médias de F0 entre os grupos. A média da idade dos grupos controle, com TRH e sem TRH foi respectivamente 30,3 anos, 54,5 anos e 56,5 anos. A média da F0 dos grupos foram respectivamente: vogal “e”: 215,97 Hz; 206,21 Hz e 200,71 Hz, e vogal “i”: 229,89 Hz; 221,79 Hz e 212,79 Hz. Os resultados mostraram uma tendência de agravamento da F0 em menopausadas, sendo a média do grupo com TRH mais próxima do grupo-controle que do grupo sem TRH. Entretanto não houve diferença estatisticamente significativa na F0 da voz para as vogais “e” (p=0,2127) e “i” (p=0,193), comparando os três grupos entre si. De acordo com esses resultados, parece não haver diferença clinicamente relevante na F0 da voz falada entre mulheres no menacme, menopausadas usuárias e não usuárias de TRH. A tendência à diminuição de F0 nas pacientes hipoestrogênicas sugere a possibilidade de que pequenas diferenças, decorrentes da influência hormonal sobre a laringe, que não tenham sido detectadas neste estudo, possam atingir maiores níveis de significância, quando os grupos forem analisados para a voz cantada. / The complaints between the women are frequent, particularly between the singers, of whom alterations in the voice occur after the menopause. It has been reported, in literature, that woman’ fundamental frequency is altered in this phase of the life. As the vocal fold possess receivers for the sexual steroids are possible that these alterations are decurrent of the observed hypoestrogenism in the climacteric. To compare the voice fundamental frequency (F0) of postmenopausal women, users and non-users of HRT with women in menache. Forty-five patients have been trialed, divided into the following groups: control group (15 women of 20 to 40 years of age, non-users of hormonal contraceptives, non smokers, with regular menstrual cycles), group with HRT (15 women of 45 to 60 years of age, menopaused for over 2 years, users of estradiol valerate 1mg/norgestimato 90mcg for a minimum period of 6 months) and the group without HRT (15 women of 45 to 60 years of age, menopaused for over 2 years, without HRT for a minimum period of 6 months). All patients had been submitted to the otolaryngological evaluation and videolaryngoscopy in order to confirm the integrity of the larynx. Afterwards F0 has been evaluated by emitting the vowels [e] and [i] in the patient’s habitual voice pitch. The F0 was analyzed using the Dr.Speech Pro. 3 software. The ANOVA test was used in order to compare the averages of F0 between the groups. The average ages of the groups control, with HRT and without HRT were respectively 30,3 years, 54,5 years and 56,5 years. The average F0 of the groups control, with HRT and without HRT were respectively: vowel [e]: 215,97Hz; 206,21Hz and 200,71Hz and vowel [i]: 229,89Hz; 221,79Hz and 212,79Hz. The results showed a trend of aggravation of the F0 in postmenopausal women, once the F0 average of the group with HRT was closer to the group control than the group without HRT. However, in a comparison between those three groups, there were no significant statistical difference in the voice F0 for the vowels [e] (p=0,2127) and [i] (p=0,193). There were no differences in F0, in the speaking voice, between women in menache and postmenopausal users and non-users of HRT. However it’s been recorded a trend in the aggravation of F0 in the postmenopausal women, mainly amongst the without HRT users. In accordance with these results seem not to have significant clinical difference in the F0 of the voice said between women in menacme, postmenopausal users and non-users of HRT. The trend the reduction of F0 in the hypoestrogenism patients suggests the possibility of that small decurrent differences of the hormonal influence on the larynx, that they have not been detected in this study, can reach greaters levels of significance when the groups will be analyzed for the sung voice.

This master‘s thesis deals with computational modelling of human vocal folds in phonation position using finite element method. There are described larynx anatomy, voice generation theories and overview of so far published computational models of vocal folds. Next part of the paper deals with a redesign of vocal folds and soft tissues‘ geometry, creation of finite element mesh and implementation of active stress in thyroarytenoid muscle. The problem was solved using Ansys 19.2 software. Computation of stress and deformation of soft tissues in phonation position has been made for 7 variations with different combination of active cartilages and muscles. Lastly, there was evaluated an effect of different cartilages and active muscle stress to final stress and deformation of soft tissues of vocal folds.

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.

This dissertation studies the synchronic phonetics of the tonation systems of five Vietic (Austroasiatic) varieties, Arem (ISO: aem), Rục (ISO: scb), and three North-Central Vietnamese (ISO: vie) dialects, Cổ Định (Thanh Hoá province), Nghi Ân (Nghệ An province), and Diêm Điền (Quảng Bình province) with the aim of improving reconstructions of Proto-Vietic tonation. Tonation is a cover term for tone and register, two phonological contrasts frequently encountered in many East and Southeast Asian languages. These two contrasts can be realized on the rhyme by differences in f0, phonation type, and duration, but also, especially in the case of register, by differences in vowel quality and by modulations of closure duration and voice onset time in onset consonants. Tone usually derives from the loss of laryngeal codas (tonogenesis), while register typically originates from the loss of voicing contrast in onset obstruents (registrogenesis). Onset devoicing can also lead to the formation of two-tone systems or double the number of tones in tonal languages. Different hypotheses have been advanced to explain the phonetic underpinnings of tone and register development, their shared phonetic properties, and intersecting segmental origins, but experimental evidence is needed to validate these hypotheses. The results show that Arem contrasts high and low registers realized by means of a breathier phonation and more closed vowels in the low register. However, Proto-Vietic final glottals, *-ʔ, *-h, and glottalized sonorant codas are still preserved in the language, and their effects on duration, f0, and phonation of preceding vowels are too variable across registers and speakers to consider Arem as tonal. The study of the tonation system of Rục shows that it has four tones in open and sonorant-ending syllables. These tones can be grouped into two high-register tones and two low-register tones that are distinguished by consistent differences in f0, phonation type, vowel quality, and to a lesser extent, vowel duration and VOT. The final fricative *-h is still preserved in Rục, and syllables ending in this coda exhibit no f0 difference, but they feature all other register properties. Hence, Rục has a hybrid system of tone and register. The results of the perception experiment reveal that Rục participants use the same phonetic cues in their perception as in their production of tonation, with roughly the same prominence for each cue. I then turn to the three North-Central Vietnamese dialects and show that they have different numbers of tones and make use of different phonetic properties to realize these tones. Different post-tonogenetic changes also led to distinct tone mergers in these dialects. Traces of register-conditioned variation in phonation type and vowel quality are limited in these varieties, but the low-register tone A2 in Diêm Điền was found to preserve breathy phonation, which is likely to be a remnant of the low register in Proto-Việt-Mường. Vowel quality was found to be conditioned by the tense phonation of tones in the low f0 range in Cổ Định and Nghi Ân, but I argue that this is not a remnant of register, a conclusion strengthened by an investigation showing that there is little evidence for register-conditioned vowel changes from Proto-Vietic to modern Northern Vietnamese. Since there is either a register contrast or remnants of register in all branches of Vietic, I propose to reconstruct a register contrast in Proto-Vietic, against previous proposals postulating that it had a voicing contrast. This register contrast evolved differently in different daughter languages and interacted with various patterns of retention of laryngeal codas, resulting in diverse tonation systems in Vietic languages. By combining insights on the typology of tonogenetic effects gained from my investigation of Rục and Arem glottal codas and on evidence from correspondences between Chinese and Sino-Vietnamese tones, I further propose that tonogenesis from codas is likely to have happened in Proto-Việt-Mường from the 9th to 12th century CE, which is later than previous proposals.

Vocal Function Exercises (VFEs) is a well-known treatment program that consists of four exercises, in which the first and fourth tasks require maximally sustained phonation. However, the active ingredients responsible for treatment efficacy are still unknown. The primary purpose of this investigation was the explore the effects of maximally sustained phonation on the VFE outcome measure of maximum phonation time (MPT) in individuals between the ages of 18-40 with normal voice. Participants were randomized into three experimental groups that completed VFEs for six weeks. The baseline group sustained tasks one and four for as long as was achieved at the baseline session; The three-week group sustained the exercises for as long as possible the first three weeks, then to their three-week MPT average for the remaining three weeks of the program; The standard group maximally sustained phonation for all six weeks. Results indicated significant improvement in percent to MPT goal attainment in the standard group and three-week group. The baseline group did not result in significant change. Including maximally sustained phonation throughout the course of VFEs is essential to producing substantial improvements in voice production, in terms of percent to MPT goal.

Vocal fold hydration is important for efficient oscillation during voice production. Dehydration of the vocal fold surface is believed to produce adverse effects on the voice. Specifically, low environmental humidity, mouth breathing, and certain medical conditions may contribute to laryngeal and vocal fold dehydration. This dehydration effect may be quantified using the observed pressure and flow at the onset of phonation, operationally defined as phonation threshold pressure (PTP) and phonation threshold flow (PTF), respectively. Previous research has documented that nebulized isotonic saline (0.9% Na+Cl-) can reduce PTP. Additionally, the topical application of liquid saline increases vocal fold hydration in excised larynx studies. However, no studies have examined the prevention of vocal fold dehydration using aerosolized saline in an excised larynx mechanical model. The purpose of the current investigation was to determine the preventive effects of aerosolized isotonic saline in a physiologically realistic excised larynx model. Using a prospective, mixed experimental design with a control group, five bench-mounted, excised porcine larynges received 4-min doses of aerosolized saline delivered supraglottally for a total of 24 min. Subsequently, larynges received 1-min doses of desiccated air (<1% relative humidity) delivered supraglottally. A control group of five porcine larynges received only desiccated air. Phonation was attempted following each dose of aerosolized saline or desiccated air. The desiccation doses were repeated for both groups until the larynges were no longer able to phonate. The PTP and PTF were measured at baseline and following each dose of aerosolized saline or desiccated air. Analysis of the results indicated that aerosolized saline significantly delayed the adverse effects of vocal fold dehydration based on the total number of desiccation doses required to cease phonation for experimental versus control groups (p = .002). Trends demonstrated that PTP decreased after aerosolized saline and increased during desiccation trials. The PTF trends were similar during desiccation. The results from this study indicate that aerosolized saline may be used prophylactically to prevent vocal fold dehydration. These findings offer important advances in vocal fold hydration theory and dehydration prevention in a physiologically realistic excised mechanical model.

Previous studies have found vocal fold hydration to be crucial for healthy function of the vocal mechanism. Surface tissue hydration facilitates efficient vocal fold oscillation. The composition of vocal fold surface fluid includes protective water and mucus layers, similar to the fluid that covers the mucosa and epithelia of the upper airway. Laryngeal dehydration has been linked to several factors such as mouth breathing, obstructive sleep apnea, dry air exposure, upper airway hypersensitivity, and certain diseases or behavioral voice use factors. Laryngeal dehydration affects phonation threshold pressure (PTP) and phonation threshold flow (PTF), defined as the pressure and flow observed at the onset of phonation, respectively. The application of topical nebulized isotonic saline (0.9% Na+Cl-) has been shown in previous work to decrease PTP. However, there are no studies examining the effects of aerosolized saline, administered supraglottally, on dehydrated excised porcine larynges. Examining the effects of aerosolized saline in an excised model is essential to determine any independent effects of this treatment in the absence of other physiologic mechanisms such as mucus secretion. This study sought to investigate the effects of aerosolized saline on dehydrated animal vocal folds to determine if the administration of supraglottic aerosolized saline, via a nebulizer, could reverse the adverse effects of laryngeal dehydration. The study included a prospective, mixed experimental design with two groups, one desiccation/aerosolization (A/B) group and a control (A) group, each comprised of five bench-mounted porcine larynges. Larynges in both groups received desiccated air (<1% relative humidity) supraglottally via custom tubing for 1-min doses until the vocal folds ceased audible phonation. Following the desiccation challenge, the A/B group received 2-min doses of aerosolized isotonic saline until phonation began again. The PTP and PTF were measured during phonation trials following each dose of the desiccation or aerosolization treatment. Significant changes in PTP and PTF were observed following both the dehydration and aerosolization treatment. The PTP increased significantly following the dehydration challenge and returned near baseline following the aerosolization treatment. The results of this investigation supported the hypothesis that the administration of aerosolized saline may reverse the adverse effects of vocal fold dehydration. Moreover, in a more physiologically realistic excised model, applying the mechanics of respiration, this study advanced the development of innovative theories related to the reversal of the adverse effects of dehydration, which may prevent the development of voice disorders.

Tube phonation is a voice treatment method for patients with voice disorders. The purpose of this study was to map speech language pathologist’s (SLPs) use of tube phonation in Sweden and to investigate the underlying factors for how the method is realized. The study consisted of a web-based questionnaire survey which 54 voice SLPs participated in. The survey consisted of closed end, open end and a combination of both. The open-end questions were partially analyzed quantatively, partially through a qualitative categorization method and were presented descriptively. The main results show that there is a strong consensus among SLPs in Sweden regarding materials used during tube phonation. The majority responded that they use glass tubes that are 27 cm long with a diameter of 9 mm, and an open bowl. These results are consistent with the recommendations in Simberg and Laine’s (2007) study where they analysed the method. In the present study, tube phonation was most commonly used to treat phonastenia, vocal nodules and vocal fold paralysis. Future treatment studies are warranted where Simberg och Laine’s (2007) recommendations are compared with other voice treatments. It would also be of interest to investigate the treatment effect of tube phonation on different voice disorders, and to investigate how SLPs should realize the treatment to achieve best possible effect. / Rörfonation är en röstbehandlingsmetod som används för patienter med röststörningar. Syftet med denna studie var att kartlägga hur röstlogopeder i Sverige använder rörfonation, samt att undersöka bakomliggande faktorer till hur metoden utförs. Studien bestod av en webbaserad enkätundersökning där 54 röstlogopeder deltog. Undersökningen bestod av slutna frågor, öppna frågor samt en kombination av båda. De öppna frågorna analyserades dels kvantitativt, dels genom en kvalitativ kategoriseringsmetod och presenterades deskriptivt. De centrala resultaten i denna studie är att röstlogopeder i Sverige är överens om vilka material som används vid rörfonation. Majoriteten av logopederna i studien använder sig av glasrör som är 27 cm långa med en diameter på 9 mm, samt en öppen skål. Dessa resultat stämmer överens med rekommendationer som Simberg och Laine (2007) ger efter att ha undersökt metoden. I föreliggande studie användes rörfonation i störst utsträckning till att behandla fonasteni, stämbandsknutor och stämbandspares. Framtida behandlingsstudier är nödvändiga för att jämföra rörfonation enligt Simberg och Laines (2007) rekommendationer med andra röstbehandlingsmetoder. Det skulle även vara intressant att undersöka utfallet/effekten av rörfonation vid olika röststörningar och hur logopeder bör utföra behandlingen för att uppnå bäst effekt.

An excised animal larynx model has been used in many studies to better understand the physiological and anatomical properties of the human larynx. One difference between an ex vivo model and an in vivo model is that ion loss occurs postmortem. To compensate for this in the excised model, researchers most commonly use a preservation method that includes completely submerging the specimen in isotonic saline (0.9% Na+Cl-) and then flash freezing it in liquid nitrogen. The flash freezing method allows researchers to maintain the integrity of the structures while also being able to gather specimens as they become available. Not enough research has been done to understand the effects of a preservation method on the outcomes of the study. Additionally, no common method has been established for preservation across studies to ensure that results are not being influenced by this variable. This prospective, mixed experimental design study includes three groups, a control group and two experimental groups. The control group consisted of 10 bench-mounted porcine larynges that were soaked in isotonic saline and flash frozen with liquid nitrogen. Prior to the experiment, the frozen larynges were thawed overnight before trials. The other two groups consisted of 10 bench-mounted porcine larynges each; these larynges were soaked in either isotonic saline or Ringer’s solution, a balanced fluid used in vivo to counteract dehydration. Larynges from these two groups were kept fresh and stored in a refrigerator overnight before trials. On the day of experimentation, each larynx was mounted on a bench top setup including three micropositioners to stabilize, adduct, and elongate the vocal folds. All the larynges were connected to a pseudolung via the trachea and humidified air was passed through to the vocal folds until phonation was achieved. Phonatory trials consisted of brief phonation followed by 5-minute desiccation intervals until phonation was no longer achieved. Phonation threshold flow (PTF), defined as the flow observed at the onset of phonation, was observed during each phonation trial; and flow values were compared within and between groups. Statistically significant differences were found between the Ringer’s group and the fresh saline group as well as between the Ringer’s group and the frozen saline group, indicating that PTF is influenced by the larynx preservation method.

While a number of studies have sought to investigate ESL speakers' fluency gains over the course of one 15-week semester, few if any studies have investigated these changes over a longer developmental period. A critical factor in researching longitudinal change is that students do not often remain in an intensive English program (IEP) for more than two semesters before moving to a new school, applying to an American university, or returning to their home country. Longitudinal research, therefore, is necessary as program administrators, teachers, and learners all seek to understand points where change in oral fluency actually occurs. For this study data were collected from students in a large intensive English program over a 45-week period. For 39 ESL learners audio files from speaking tasks that were part of placement and end-of-semester level achievement tests were collected and analyzed. Specific oral fluency features such as speech rate, articulation rate, and pause frequency were investigated. This thesis will share the results of the analysis while also discussing the implications of the data for program administrators, teachers, and learners. Particular focus will be given to helping stakeholders understand specific changes that occurred in learners' fluency over the time period of three semesters.