Stimulation of the Premotor Cortex Enhances Interhemispheric Functional Connectivity in Association with Upper Limb Motor Recovery in Moderate-to-Severe Chronic Stroke

作者：Robert Unger, Mark J. Lowe, Erik B. Beall, François Béthoux, Stephen E. Jones, André G. Machado, Ela B. Plow, David A. Cunningham · 发表于：Brain Connectivity · 年份：2023 · DOI：10.1089/brain.2022.0064 · 被引用次数：29 · 研究领域：Transcranial Magnetic Stimulation Studies、Stroke Rehabilitation and Recovery、Functional Brain Connectivity Studies

Background: Transcranial direct current stimulation (tDCS) targeting the primary motor cortex is modestly effective for promoting upper-limb motor function following stroke. The premotor cortex (PMC) represents an alternative target based on its higher likelihood of survival and dense motor-network connections. Objective: The objective of this study was to determine whether ipsilesional PMC tDCS affects motor network functional connectivity (FC) in association with reduction in motor impairment, and to determine whether this relationship is influenced by baseline motor severity. Methods: Participants with chronic stroke were randomly assigned to receive active-PMC or sham-tDCS with rehabilitation for 5 weeks. Resting-state functional magnetic resonance imaging was acquired to characterize change in FC across motor-cortical regions. Results: Our results indicated that moderate-to-severe participants who received active-tDCS had greater increases in PMC-to-PMC interhemispheric FC compared to those who received sham; this increase was correlated with reduction in proximal motor impairment. There was also an increase in intrahemispheric dorsal premotor cortex-primary motor cortex FC across participants regardless of severity or tDCS group assignment; this increase was correlated with a reduction in proximal motor impairment in only the mild participants. Conclusions: Our findings have significance for developing targeted brain stimulation approaches. While participants with milde...