Selectively disrupted sensorimotor circuits in chronic stroke with hand dysfunction

• Authors: FeiWen Liu, Chengdu Second People's Hospital; ChangCheng Chen, Qingtian People's Hospital; WenJun Hong, Medical School of Nanjing University; ZhongFei Bai, Shanghai Sunshine Rehabilitation Center; SiZhong Wang, University of Otago; HanNa Lu, Chinese University of Hong Kong; QiXiang Lin, Emory University School of Medicine; ZhiYong Zhao, College of Biomedical Engineering & Instrument Science, Zhejiang University; ChaoZheng Tang, National Health Commission of the People's Republic of China
• Journal Title: CNS Neuroscience and Therapeutics
• Volume: Volume 28, Number 5
• Publisher: John Wiley & Sons, Inc | 2022-05-01, Pages 677-689
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.1111/cns.13799
• Subjects: Health Sciences, Rehabilitation and Therapy; Engineering, Biomedical
• Keywords: Granger causality analysis; effective connectivity; functional reorganization; resting-state functional magnetic resonance imaging; stroke; Hand; Humans; Magnetic Resonance Imaging; Motor Cortex; Recovery of Function; Stroke

Abstract

Aim: To investigate the directional and selective disconnection of the sensorimotor cortex (SMC) subregions in chronic stroke patients with hand dysfunction. Methods: We mapped the resting-state fMRI effective connectivity (EC) patterns for seven SMC subregions in each hemisphere of 65 chronic stroke patients and 40 healthy participants and correlated these patterns with paretic hand performance. Results: Compared with controls, patients demonstrated disrupted EC in the ipsilesional primary motor cortex_4p, ipsilesional primary somatosensory cortex_2 (PSC_2), and contralesional PSC_3a. Moreover, we found that EC values of the contralesional PSC_1 to contralesional precuneus, the ipsilesional inferior temporal gyrus to ipsilesional PSC_1, and the ipsilesional PSC_1 to contralesional postcentral gyrus were correlated with paretic hand performance across all patients. We further divided patients into partially (PPH) and completely (CPH) paretic hand subgroups. Compared with CPH patients, PPH patients demonstrated decreased EC in the ipsilesional premotor_6 and ipsilesional PSC_1. Interestingly, we found that paretic hand performance was positively correlated with seven sensorimotor circuits in PPH patients, while it was negatively correlated with five sensorimotor circuits in CPH patients. Conclusion: SMC neurocircuitry was selectively disrupted after chronic stroke and associated with diverse hand outcomes, which deepens the understanding of SMC reorganization.