Emergence and Refinement of Respiratory Chest Wall Intermuscular Coherence Associated with Speech and Non-Speech Tasks in Younger and Older Children

• Author / Creator

  Bremmekamp, Darian J

• Introduction: There is limited information about the development of chest wall muscular control of lung volume and alveolar pressure for non-speech and speech tasks. The present study was the first in a series of studies aimed at achieving an in-depth understanding of intermuscular coherence of the chest wall for voluntary breathing during non-speech and speech tasks in typically developing children. Specifically, this investigation examined breathing kinematics, chest wall muscle activation patterns, and intermuscular coherence associated with non-speech and speech tasks varying on features of lung volume excursions and alveolar pressure targets. Methods: A mixed experimental design was employed on a cross-section of 15 younger children aged 6-9 years and 15 older children aged 13-16 years. Respiratory kinematics using variable inductance plethysmography along with intercostal and oblique muscular activity and intermuscular coherence derived from surface electromyography were analyzed for a series of tasks including: (a) vital capacity manoeuvres, (b) maximum duration phonation produced at conversational and perceived twice-conversational loudness, (c) sentence repetition produced at conversational and perceived twice-conversational loudness and (e) expiratory threshold loading (ETL) at maximal and submaximal expiratory pressures (MEPs). Data were collected in a single testing session. Results: The main findings were: (1) Breathing kinematic patterns for speech were similar between the two groups of children whereas breathing patterns differed for tasks involving larger alveolar pressure requirements or greater lung volume excursions; (2) Muscle activation amplitudes and intermuscular coherence differed between the two age groups for tasks involving speech production; and (3) Within groups, intermuscular control for task specificity was more precisely developed in the older group compared to the younger group of children. Conclusion: Consistent with previously documented changes in speech breathing kinematics during development from childhood to adolescence, these data provide evidence that children also are undergoing age related changes in intermuscular coherence for speech breathing. Intermuscular coherence appeared to be task specific for both groups of children but more so in the older children. Based on strength of peak coherence, older children exhibited increased intermuscular coherence and greater muscular coordination during speech breathing in comparison, younger children who exhibited lower intermuscular coherence had a lower amount of muscle coordination. Both older and younger children displayed decreased muscle coordination for non-learned, non-speech tasks requiring maximal lung volume and/or pressure generation (i.e., maximum performance tasks and expiratory threshold loading). Further research is required to classify the relationship between strength of intermuscular coherence and distribution of the signal through the corticospinal tract. The results of this study may contribute to informing voice and speech treatment interventions targeting children and adolescents with neurogenic communication disorders involving the respiratory-laryngeal subsystems.

• Subjects / Keywords

  • Chest Wall Muscular Control
  • Emergence
  • Developmental
  • Intermuscular Coherence
  • Speech Breathing

• Graduation date

  Spring 2018

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R30V89Z37

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.