Lange F, Eldebakey H, Hilgenberg A, Weigl B, Eckert M, DeSunda A, Neugebauer H, Peach R, Roothans J, Volkmann J, Reich MM.
Parkinsonism Relat Disord.
Deep brain stimulation of the subthalamic nucleus is an effective treatment of Parkinson’s disease, yet it is often associated with a general deterioration of speech intelligibility. Clustering the phenotypes of dysarthria has been proposed as a strategy to tackle these stimulation-induced speech problems.
In this study, we examine a cohort of 24 patients to test the real-life application of the proposed clustering and attempt to attribute the clusters to specific brain networks with two different approaches of connectivity analysis.
Both our data-driven and hypothesis-driven approaches revealed strong connections of variants of stimulation-induced dysarthria to brain regions that are known actors of motor speech control. We showed a strong connection between the spastic dysarthria type and the precentral gyrus and supplementary motor area, prompting a possible disruption of corticobulbar fibers. The connection between the strained voice dysarthria and more frontal areas hints toward a deeper disruption of the motor programming of speech production.
These results provide insights into the mechanism of stimulation-induced dysarthria in deep brain stimulation of the subthalamic nucleus and may guide reprogramming attempts for individual Parkinson’s patients based on pathophysiological understanding of the affected networks.