Project Summary
Respiratory data from five existing human subject datasets will be merged in order to comprehensively
examine the dynamic and coordinated movements of the chest wall system (thorax and abdomen) in persons
with Parkinson’s disease (PD). The precisely coordinated movements of the chest wall are critical for
optimizing speech production and minimizing the work of breathing. One of the most salient speech and voice
symptoms associated with PD is a reduction in speaking volume, a condition known as hypophonia.
Hypophonia is estimated to occur in 80-89% of persons with PD and leads to social isolation and depression
due to a significant adverse impact on spoken communication. Hypophonia has been attributed to several
physiological factors including reduced ribcage compliance, decreased abdominal support, and reduced vocal
fold closure. Asynchronous movement of the chest wall system, however, may be another contributing factor,
which is presently not accounted for in our voice intervention protocols. It is widely reported that persons with
PD exhibit a myriad of motor coordination issues, stemming from basal ganglia and cerebellar dysfunction,
including impaired fine motor dexterity, postural instability, and abnormal gait characteristics. An empirical
study of the dynamic and coordinated movements of the chest wall system during breathing, however, is
lacking in persons with PD. To date, studies have described pulmonary restriction in persons with PD using
static measures of respiratory function (e.g. respiratory muscle strength and vital capacity). There is a critical
need to study the dynamic movement of the respiratory system in order to develop effective and efficacious
approaches to voice intervention. The present application seeks to address this paucity of data through a novel
exploration of thoracoabdominal asynchrony (TAA) and paradoxical motion in a large sample of persons with
PD (n=110). Small-scale studies on TAA and paradoxical motion suggest a high prevalence in persons with
PD during rest breathing. The present application will examine the dynamic movement of the thoraco-
abdominal system across the inspiratory and expiratory cycles of rest and speech breathing (Specific Aim 1)
using standardized measures from the literature. Targeting TAA during speech breathing is innovative as this
has not been studied in any population yet. Further, this study will examine how current voice intervention
protocols, which directly or indirectly target respiration, impact the coordination of the thoraco-abdominal
system during speech production (Specific Aim 2). Our application addresses NHBLI Strategic Objective 5: “To
develop and optimize novel diagnostic and therapeutic strategies to prevent, treat, and cure National Heart,
Lung, and Blood (NHLB) diseases.” The knowledge gained from this study has the power to transform our
approach to voice and respiratory interventions for persons with PD and lead to efficacious and potentially new
treatment protocols.