间歇性Theta爆发式磁刺激提高脑机接口在中风后上肢康复中的疗效

BACKGROUND: "BCI illiteracy," characterized by insufficient μ-rhythm Event-Related Desynchronization (ERD) in approximately 40% of stroke patients, limits the efficacy of Brain-Computer Interface (BCI) training. Intermittent Theta Burst Stimulation (iTBS) can modulate cortical excitability. We hypothesized that sequential application of iTBS over the affected primary motor cortex (M1) before BCI training may enhance cortical activation, improve BCI decoding efficiency, and thereby promote upper limb motor recovery after stroke.

METHODS: This exploratory single-center randomized controlled trial (RCT) enrolled 18 subacute stroke patients, randomized to: BCI group (conventional rehab + BCI training) or iTBS + BCI group (conventional rehab + iTBS applied to the affected M1 cortex followed sequentially by BCI training). Interventions occurred 10 times over 2 weeks. Primary outcome: Fugl-Meyer Assessment - Upper Extremity (FMA-UE) score. Secondary outcomes: Modified Barthel Index (MBI), BCI task accuracy (BCI-TA). Mechanistic measures: sensorimotor cortex ERD and Laterality Index (LI).

RESULTS: In this exploratory study, FMA-UE improvement was greater in the iTBS + BCI group, with significant differences at week 4 (Z = 2.569, p = 0.008). iTBS + BCI group showed a greater BCI-TA increase (87.22 ± 10.83% vs. 68.24 ± 5.75%, p = 0.041), which correlated negatively with attention improvement (Schulte test time reduction; r = -0.796, p < 0.001). Only the iTBS+BCI group demonstrated deeper ERD over the affected sensorimotor cortex (C4; p = 0.001) and a shift in LI towards the affected side (p = 0.017) during affected hand motor imagery.

CONCLUSION: This exploratory study suggests that sequential iTBS combined with BCI may have potential benefits in enhancing upper limb function in stroke patients. It boosts affected cortical excitability, improves BCI decoding efficiency, and remodels motor network activation, offering a new strategy to overcome "BCI illiteracy."

CLINICAL TRIAL REGISTRATION: https://www.chictr.org.cn/showproj.html?proj=173657, Identifier: ChiCTR2300069203.