The influence of flow separation location on eigenmode synchronization and phonation onset was investigated in a two-dimensional, aeroelastic, continuum model of phonation. A linear stability analysis showed that flow separation played a critical role in initiating eigenmode synchronization and phonation. For a given glottal configuration, a small variation in the flow separation location along...

PURPOSE To assess the benefits of a group vocal improvement program to popular singers without voice disorders. METHODS This is a quasi-experimental intervention study, carried out with 37 popular singers of both genders, with ages between 18 and 40 years and adapted vocal quality. Participants were divided into two groups: Intervention (IG) and Control (CG). The IG included 21 subjects who p...

A combination of non invasive acoustic and aerodynamic measures were used to analyze vocal function in three patients treated by CO2 Laser posterior transverse cordotomy for bilateral vocal fold paralysis. Measures included : (i) Frequency features : fundamental frequency, standard deviation, jitter, shimmer and harmonic-to-noise ratio, (ii) Several measures on the spectra of vowel /a/ : firstf...

PURPOSE In the present study, the authors investigated the association between wet vocal quality (WVQ) and prandial material in the larynx during phonation. The presence of such material is indicative of oropharyngeal dysphagia and results from entry of material into the laryngeal vestibule during swallowing. The primary aim of the study was to determine whether clinicians reliably perceive WVQ...

The frequencies, magnitudes, and bandwidths of vocal tract resonances are all important in understanding and synthesizing speech. High precision acoustic impedance spectra of the vocal tracts of 10 subjects were measured from 10 Hz to 4.2 kHz by injecting a broadband acoustic signal through the lips. Between 300 Hz and 4 kHz the acoustic resonances R (impedance minima measured through the lips)...

Background: individuals with Parkinson's disease present voice and speech alterations, especially regarding loudness and speech rate. Aim: to determine the immediate effect of modified auditory feedback: amplification, delay and masking in the voice and speech of individuals with Parkinson's disease, according to gender. Method: twenty-six subjects with Parkinson's disease (15 men and 11 women)...

Parkinson's disease (PD) is well known to cause voice impairments. The aim of this study is to evaluate subjective and objective changes in voice quality in patients with PD in Croatian language speakers. Twenty one patients (11 male and 10 female) with PD and twenty one age-matched (10 male and 11 female) of the control group were assessed. Voice impairment was scored according to Voice Handic...

Wilson disease (WD) is a rare genetic disorder characterized by copper overload in the liver and the brain. Neurological presentations are mainly related to the accumulation of copper in the basal ganglia, the brainstem, and the cerebellum. Dysarthria is a frequent symptom, with dystonic, spastic, or parkinsonian components and is usually resistant to medical or voice rehabilitation therapies. ...

Pulsatile two-dimensional flow through static divergent models of the human vocal folds is investigated. Although the motivation for this study is speech production, the results are generally applicable to a variety of engineering flows involving pulsatile flow through diffusers. Model glottal divergence angles of 10, 20, and 40 represent various geometries encountered in one phonation cycle. F...