%A Hu,Mengjiao %A Cheng,Hsiao-Ju %A Ji,Fang %A Chong,Joanna Su Xian %A Lu,Zhongkang %A Huang,Weimin %A Ang,Kai Keng %A Phua,Kok Soon %A Chuang,Kai-Hsiang %A Jiang,Xudong %A Chew,Effie %A Guan,Cuntai %A Zhou,Juan Helen %D 2021 %J Frontiers in Human Neuroscience %C %F %G English %K functional magnetic resonance imaging,Stroke,Amplitude of low-frequency fluctuation,regional homogeneity,functional connectivity,brain-computer interface-assisted motor imagery,transcranial direct current stimulation %Q %R 10.3389/fnhum.2021.692304 %W %L %M %P %7 %8 2021-July-16 %9 Original Research %# %! Brain changes in stroke rehabilitation %* %< %T Brain Functional Changes in Stroke Following Rehabilitation Using Brain-Computer Interface-Assisted Motor Imagery With and Without tDCS: A Pilot Study %U https://www.frontiersin.org/articles/10.3389/fnhum.2021.692304 %V 15 %0 JOURNAL ARTICLE %@ 1662-5161 %X Brain-computer interface-assisted motor imagery (MI-BCI) or transcranial direct current stimulation (tDCS) has been proven effective in post-stroke motor function enhancement, yet whether the combination of MI-BCI and tDCS may further benefit the rehabilitation of motor functions remains unknown. This study investigated brain functional activity and connectivity changes after a 2 week MI-BCI and tDCS combined intervention in 19 chronic subcortical stroke patients. Patients were randomized into MI-BCI with tDCS group and MI-BCI only group who underwent 10 sessions of 20 min real or sham tDCS followed by 1 h MI-BCI training with robotic feedback. We derived amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and functional connectivity (FC) from resting-state functional magnetic resonance imaging (fMRI) data pre- and post-intervention. At baseline, stroke patients had lower ALFF in the ipsilesional somatomotor network (SMN), lower ReHo in the contralesional insula, and higher ALFF/Reho in the bilateral posterior default mode network (DMN) compared to age-matched healthy controls. After the intervention, the MI-BCI only group showed increased ALFF in contralesional SMN and decreased ALFF/Reho in the posterior DMN. In contrast, no post-intervention changes were detected in the MI-BCI + tDCS group. Furthermore, higher increases in ALFF/ReHo/FC measures were related to better motor function recovery (measured by the Fugl-Meyer Assessment scores) in the MI-BCI group while the opposite association was detected in the MI-BCI + tDCS group. Taken together, our findings suggest that brain functional re-normalization and network-specific compensation were found in the MI-BCI only group but not in the MI-BCI + tDCS group although both groups gained significant motor function improvement post-intervention with no group difference. MI-BCI and tDCS may exert differential or even opposing impact on brain functional reorganization during post-stroke motor rehabilitation; therefore, the integration of the two strategies requires further refinement to improve efficacy and effectiveness.