Dual-task performance in Parkinson disease (Whitfield et al., 2019)

Purpose: Prior investigations suggest that simultaneous performance of more than 1 motor-oriented task may exacerbate speech motor deficits in individuals with Parkinson disease (PD). The purpose of the current investigation was to examine the extent to which performing a low-demand manual task affected the connected speech in individuals with and without PD.
Method: Individuals with PD and neurologically healthy controls performed speech tasks (reading and extemporaneous speech tasks) and an oscillatory manual task (a counterclockwise circle-drawing task) in isolation (single-task condition) and concurrently (dual-task condition).
Results: Relative to speech task performance, no changes in speech acoustics were observed for either group when the low-demand motor task was performed with the concurrent reading tasks. Speakers with PD exhibited a significant decrease in pause duration between the single-task (speech only) and dual-task conditions for the extemporaneous speech task, whereas control participants did not exhibit changes in any speech production variable between the single- and dual-task conditions.
Conclusions: Overall, there were little to no changes in speech production when a low-demand oscillatory motor task was performed with concurrent reading. For the extemporaneous task, however, individuals with PD exhibited significant changes when the speech and manual tasks were performed concurrently, a pattern that was not observed for control speakers.

Supplemental Material S1. Visual representation of the algorithm used to compute within- trial kinematic variation. The standard deviation of the radius was calculated by first computing the standard deviations of all cycle radii within the 10-degree windows, and then the standard deviations from each window were averaged to arrive at an aggregate variance metric.

Supplemental Material S2. Animation of 30 seconds of a manual movement trace produced by a control participant in the single-task condition (i.e., circling alone).

Supplemental Material S3. Animation of 30 seconds of a manual movement trace produced by a participant with Parkinson disease (PD) in the single-task condition (i.e., circling alone). Note: the Hoehn and Yahr (H&Y) stage for this participant was 3.

Whitfield, J. A., Kriegel, Z., Fullenkamp, A. M., & Mehta, D. D. (2019). Effects of concurrent manual task performance on connected speech acoustics in individuals with Parkinson disease. Journal of Speech, Language, and Hearing Research, 62, 2099–2117. https://doi.org/10.1044/2019_JSLHR-S-MSC18-18-0190

Publisher Note: This article is part of the Forum: Selected Papers From the 2018 Conference on Motor Speech—Basic Science and Clinical Innovation.