Abstract
This study tested the assumption that speech is more susceptible to fatigue than normal in persons with dysarthria. After 1 h of speech-like exercises, participants with Parkinson's disease (PD) were expected to report increased perceptions of fatigue and demonstrate fatigability by producing less precise speech with corresponding acoustic changes compared to neurologically normal participants. Twelve adults with idiopathic PD and 13 neurologically normal adults produced sentences with multiple lingual targets before and after six 10-min blocks of fast syllable or word productions. Both groups reported increasing self-perceived fatigue over time, but trained listeners failed to detect systematic differences in articulatory precision or speech naturalness between sentences produced before and after speech-related exercises. Similarly, few systematic acoustic differences occurred. These findings do not support the hypothesis that dysarthric speakers are particularly susceptible to speech-related fatigue; instead, speech articulation generally appears to be resistant to fatigue induced by an hour of moderate functional exercises.
Declaration of interest
The authors report no conflicts of interest. This research was supported in part by NIDCD Grant R03 DC06096. The views expressed in this article are those of the authors and do not reflect the official policies of the Departments of the Air Force, Army, Navy, the Department of Defense, or the U.S. Government. A portion of this study was presented at the Conference on Motor Speech in March 2006 in Austin, TX, and a summary of preliminary results was published in Solomon (Citation2006) based on a presentation at the University of Wisconsin-Madison Medical School Swallowing Conference: New Frontiers in Dysphagia Rehabilitation.