Background Stroke is a global, major and disabling non-communicable disease. Among acute stroke survivors, 50%−80% will experience upper limb dysfunction. While Taiji Yunshou (TY) and transcranial direct current stimulation (tDCS) demonstrate individual efficacy, the neurophysiological effects and mechanisms of their synchronous application at the hemodynamic brain network level remain unclear. This study compared the transient neurophysiological effects of the isolated vs. combined interventions on cortical activation and cross-subject hemodynamic brain network topology in left-hemispheric stroke. Methods 10 participants underwent three randomized 20-min brief interventions with 2-day washout periods: TY alone, tDCS alone, and synchronous TY + tDCS. Functional near-infrared spectroscopy (fNIRS) quantified the difference between post-intervention and pre-intervention oxygenated hemoglobin concentration changes (ΔHbO) under different conditions for intervention across left and right prefrontal cortex LPFC, RPFC, premotor and supplementary motor cortex LPMC, RPMC, and sensorimotor cortex LSMC, RSMC. The differences in ΔHbO among the three brief interventions were analyzed using Friedman test with Nemenyi test for post hoc pairwise comparisons. Cross-subject hemodynamic brain networks were also constructed using Graphical Least Absolute Shrinkage and Selection Operator (GLASSO) for three brief interventions, with community detection, nodal centrality metrics, edge betweenness, and global indicators also analyzed. Results Synchronous TY + tDCS induced superior LPFC and RPFC activation vs. tDCS alone (LPFC: p 0.01; RPFC: p 0.05). tDCS alone and TY + tDCS both elicited greater LPMC activation than TY alone ( p 0.001). Each intervention caused specific network reorganization. TY formed motor-execution and cognitive-control communities. tDCS created a bipartite division with LSMC-RPMC inhibitory connection. TY + tDCS segregated LPFC and RPFC into a cognitive community in common with LPFC-RPMC and LPFC-LSMC inhibitory connections, LSMC as the principal hub and optimized global network efficiency. Conclusion Synchronous TY + tDCS induced synergistic neuroplasticity through dual mechanisms, enhancing cognitive-motor integration and LSMC-driven interhemispheric network reorganization. These findings provide clinical neuroimaging evidence at the channel level and the cross-subject level for integrated rehabilitation paradigms and identify LSMC as a critical target for stroke recovery. Clinical trial registration https://www.chictr.org.cn/ , identifier ChiCTR2400088853.
Lin et al. (Thu,) studied this question.