Aerodynamic and temporal disruptions of speech in laryngeal insufficiency.

Abstract

To describe the effects of laryngeal insufficiency on aerodynamic and temporal aspects of speech breathing and speech production. A survey study with statistical comparisons of patient and normal subject groups. Private and institutional practice. A convenience sample of 23 subjects with laryngeal insufficiency was compared with a volunteer sample of 20 normal-speaking subjects. Patients had frank unilateral recurrent nerve paralysis-paresis or idiopathic laryngeal insufficiency as verified by videostrobolaryngoscopy. Mean airflows, air volumes, and durations for speech inspirations, speech phrases, and non-inspiratory pauses during samples of monologue speech. In comparison with the normal group, the patient group had significantly (P < .01) higher expiratory airflows and volumes during speech and reduced speech phrase durations. In addition, breaths per minute, inspiratory minute volume, and inspiratory airflow were significantly (P < .01) higher for the patient group. An experimental measure of aerodynamic yield for speech increased the statistical separation of the patient and normal groups compared with analyses using simple expiratory airflow measures alone. Insufficient contact of the true vocal folds during speech can affect more than just voice quality. Likely effects include (1) reduced speech phrase duration, (2) increased breaths per minute, (3) increased inspiratory minute volume, and (4) increased inspiratory airflow rate.