Respiratory kinematics and laryngeal aerodynamics in speech of individuals with multiple sclerosis

Purpose: The purpose of this study was to compare speech breathing and laryngeal airstream valving in individuals with MS to healthy age- and sex-matched peers.;Methods: Fifteen individuals with MS, consisting of ten females and five males, and fifteen age- and sex-matched healthy control participants produced speech tasks for respiratory kinematic measures which were collected using transductance bands around the rib cage and abdomen. All participants also produced sustained vowel and syllable repetition tasks for laryngeal aerodynamic measures of oral airflow and intraoral air pressure, which were collected using a circumferentially-vented pneumotachograph. A series of one-way ANOVAs analyzed respiratory kinematic measures of lung, rib cage and abdominal volumes, vocal intensity, utterance length and rate, air usage per syllable, as well as laryngeal aerodynamic, and intraoral air pressure measures.;Results: The individuals with MS started and ended speech at higher volumes, spoke at a significantly lower vocal intensity, produced shorter utterances at a slower rate, and used more air per syllable than their healthy peers. The individuals with MS also had their vocal folds open for a longer duration of the overall cycle, and had vocal folds more open at the point of greatest closure in the cycle than their healthy peers.;Conclusions: The individuals with MS spoke at a lower vocal intensity than their healthy peers, while using differing respiratory strategies. It is likely the patterns observed in individuals with MS were associated with less efficient speech breathing patterns and greater energy usage while speaking. Individuals with MS also experienced a more open overall glottal configuration. Speech breathing results, in conjunction with laryngeal valving differences, showed a distinctly different pattern of respiratory-laryngeal interdependence in the individuals with MS from their healthy peers. Results of the present study highlight the importance of screening and assessment of speech breathing and laryngeal function, even in highly intelligible, mildly dysarthric, individuals with MS.