Analysis of nonlinear dynamics of vocal folds using high-speed video observation and biomechanical modeling

Primary voice production occurs in the larynx through vibrational movements carried out by vocal folds. However, many problems can affect this complex system resulting in voice disorders. In this context, time-frequency-shape analysis based on embedding phase space plots and nonlinear dynamics methods have been used to evaluate the vocal fold dynamics during phonation. For this purpose, the present work used high-speed video to record the vocal fold movements of three subjects and extract the glottal area time series using an image segmentation algorithm. This signal is used for an optimization method which combines genetic algorithms and a quasi-Newton method to optimize the parameters of a biomechanical model of vocal folds based on lumped elements (masses, springs and dampers). After optimization, this model is capable of simulating the dynamics of recorded vocal folds and their glottal pulse. Bifurcation diagrams and phase space analysis were used to evaluate the behavior of this deterministic system in different circumstances. The results showed that this methodology can be used to extract some physiological parameters of vocal folds and reproduce some complex behaviors of these structures contributing to the scientific and clinical evaluation of voice production. (C) 2010 Elsevier Inc. All rights reserved.

Análise sistemática dos benefícios do uso do implante coclear na produção vocal

OBJETIVO: Realizar uma revisão sistemática de pesquisas relacionadas às características vocais de crianças ou adultos com deficiência auditiva usuários de implante coclear. ESTRATÉGIAS DE PESQUISA: Foi realizada uma busca com os descritores voz, qualidade da voz e implante coclear, e seus respectivos correspondentes na língua inglesa, nas bases de dados Web of Science, Bireme, portal de teses e dissertações da USP e banco de teses e dissertações da CAPES. CRITÉRIOS DE SELEÇÃO: Os critérios adotados incluíram título condizente com a proposta deste estudo, casuística necessariamente englobando crianças ou adultos com deficiência auditiva de grau severo a profundo, pré ou pós-linguais, usuários de implante coclear e que tenham passado por análise perceptivo-auditiva e/ou acústica da qualidade vocal. RESULTADOS: Vinte e sete trabalhos foram classificados seguindo-se os níveis de evidências e indicadores de qualidade empregados pela American Speech-Language-Hearing Association (ASHA). Os desenhos dos trabalhos analisados foram considerados de média e baixa evidência científica. Seis trabalhos foram classificados como nível de evidência IIb, 20 como III, e um como IV. CONCLUSÃO: A qualidade vocal da criança ou adulto com deficiência auditiva usuário de implante coclear tem sido estudada em pequena escala. Não há um número efetivo de estudos com alto índice de evidência que demonstrem com precisão os efeitos do implante coclear na qualidade vocal desses indivíduos.

Research on the vocal culture of Orcinus orca in the Loro Parque, Tenerife: a pilot study

This research is focussed on the study of Orcinus orca's communication system. The analysis of vocalizations emitted by marine mammals has started in the '80s and most studies have been carried out in the wild. In this regard the most studied animal has been common dolphin (Tursiops truncatus) as the numerous presence of captive individuals worldwide made researches easier to be carried out. Studies about Orcinus orca's vocalizations have mainly been carried out in the wild (most in British Columbia) because its maintenance in a controlled environment results to be very difficult, only 17 among parks and oceanaria worldwide have some Orcinus orca (45 overall among which 64% born in captivity). These researches showed that Orcinus orca emit three main different types of sounds, classified as: whistles, clicks and calls. Besides, it was discovered that different groups (pods) produce sounds belonging only to the relevant pod (dialects). It is rare to find two pods sharing some calls. The two pods usually live in adjacent areas and can form a clan. This study was carried out in a controlled environment in the Orca ocean structure (Loro Parque, Tenerife, Spain) where, at the moment (March 2012) 6 individuals are hosted. Here it was developed an automatic sound recording system. Thanks to the use of suitable mathematical algorithms that allow to isolate only "interesting" sound events that differ from the "background noise", it was possible to create a database. The visualization of the sound events collected in the database is carried out with the use of a software. By looking at this output and at the observation register we could match the animal to the sound produced. Three situations were detected and studied: 1) Chosen alone: the animal chooses to go to the recording pool but it is free to move to another pool with other individuals. 2) Put alone: the animal is put alone in the recording pool. 3) With other orcas: more animals are together in the recording pool. The statistic analysis show that animals emit more vocalizations when they are in the situation "Chosen alone". The research will continue in order to observe eventual differences in the individual repertoire of each Orcinus orca.

That Female Sound: Uptalk and Vocal Fry

This paper presents an analysis of women's voices, with a particular focus on how they are often criticized, and a discussion about two linguistic trends popular among them: uptalk and vocal fry

Vocal cord dysfunction: dealing with aggressivity

QUESTIONS UNDER STUDY: Vocal cord dysfunction (VCD) is characterised by recurrent attacks of paradoxical adduction of the vocal cords during inspiration, accompanied clinically by dyspnoea attacks with inspiratory stridor lasting between minutes and hours. The aim of the study is to evaluate the self-perception of patients suffering from VCD and how they deal with aggressivity. METHODS: The Giessen Test (GT) and the Picture Frustration Test (PFT) were used on 6 patients with VCD. RESULTS: Five variables show significant differences between the patients with VCD and the values of the normative groups. VCD-patients show an idealized image of themselves, ie relaxed, open, sociable, and capable of devotion. They do not reject accusations against them by others and rarely make self-criticism. In conflicts they behave passively, thus blocking their expression of aggressivity. CONCLUSIONS: In many cases organic disposition and trigger stimuli are thought to be responsible for provoking dyspnoea attacks in VCD. However, the self-perception of patients and their way of dealing with aggressivity strongly suggests that psychosocial factors play a great role in the development of VCD. This requires not only symptom-orientated therapy but also psychological counselling.

Randomized controlled trial on single dose steroid before thyroidectomy for benign disease to improve postoperative nausea, pain, and vocal function

OBJECTIVE: To evaluate the effects of a single preoperative dose of steroid on thyroidectomy outcomes. BACKGROUND: Nausea, pain, and voice alteration frequently occur after thyroidectomy. Because steroids effectively reduce nausea and inflammation, a preoperative administration of steroids could improve these thyroidectomy outcomes. METHODS: Seventy-two patients (men = 20, women = 52) undergoing thyroidectomy for benign disease were included in this randomized, controlled, 2 armed (group D: 8 mg dexamethasone, n = 37; group C: 0.9% NaCl, n = 35), double-blinded study (clinical trial number NCT00619086). Anesthesia, surgical procedures, antiemetics, and analgesic treatments were standardized. Nausea (0-3), pain (visual analog scale), antiemetic and analgesic requirements, and digital voice recording were documented before and 4, 8, 16, 24, 36, and 48 hours after surgery. Patients were followed-up 30 days after hospital discharge. RESULTS: Baseline characteristics were similar among the 2 treatment groups. Nausea was pronounced in the first 16 hours postoperatively (scores were <0.3 and 0.8-1.0 for group D and C, respectively (P = 0.005)), and was significantly lower in group D compared with group C during the observation period (P = 0.001). Pain diminished within 48 hours after surgery (visual analog scale 20 and 35 in group D and C, respectively (P = 0.009)). Antiemetic and analgesic requirements were also significantly diminished. Changes in voice mean frequency were less prominent in the dexamethasone group compared with the placebo group (P = 0.015). No steroid-related complications occurred. CONCLUSION: A preoperative single dose of steroid significantly reduced nausea, vomiting, and pain, and improved postoperative voice function within the first 48 hours (most pronounced within 16 hours) after thyroid resection; this strategy should be routinely applied in thyroidectomies.

Die beiden Systeme der hebräischen Vocal- und Accentzeichen

Michel Friedländer

Vocal tract settings in speakers suffering from obstructive sleep apnea síndrome

Automatic systems based on speech signal analysis for the early dete ction of obstructive sleep apnea (OSA) have achieved fairly high performance rates in recent years. However, a satisfactory explanation of these results has not been available. This presentation aims at explaining via an examination of the long-term spectra of OSA patients and normal control speakers these systems’ ability to discover OSA speakers on the base of all-purpose cepstral coefficients. An in terpretation of the long- term spectra in terms of the underlying tract settings suggests that the speech of OSA patients is characterized by a pharyngeal narrowing that may be captured by acoustic cues of the spectral contour of windowed speech frames. A novel interpretation of long-term spectra in terms of the first principal component of the temporal sequence of short-term amplitude-spectra is also discussed.