Interhemispheric Functional Reorganization and its Structural Base After BCI-Guided Upper-Limb Training in Chronic...

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomedical Engineering

Background:

• Brain-computer interface (BCI)-guided robot-assisted training is emerging for stroke rehabilitation.
• Long-term neuroplasticity modulation following BCI training requires further characterization.

Purpose of the Study:

• To investigate functional reorganization and its structural basis after BCI-guided robot-assisted upper-limb training in chronic stroke survivors.
• To explore clinical and neurological changes six months post-training.

Main Methods:

• Utilized resting-state fMRI, task-based fMRI, and diffusion tensor imaging (DTI) in 14 chronic stroke subjects.
• Assessed changes before, immediately after, and six months after 20 sessions of BCI-guided robot hand training.
• Employed seed-based analysis, repeated measure ANOVA, and multiple linear regression models.

Main Results:

• Long-term motor improvement was observed post-training (p = 0.006).
• Significant functional connectivity (FC) modulation occurred between ipsilesional motor regions (M1, SMA) and contralesional areas (SMA, PMd, SPL).
• Improved FC with ipsilesional M1 correlated with motor function gains (r = 0.6455, p = 0.0276).
• Increased interhemispheric FC and laterality index indicated hemispheric rebalancing.
• Motor improvement and functional changes were associated with ipsilesional corticospinal tract integrity.

Conclusions:

• BCI-guided robot training promotes long-term motor recovery in stroke patients.
• Neuroplasticity involves interhemispheric interaction and is supported by structural integrity of motor pathways.
• Findings enhance understanding of stroke recovery mechanisms and BCI's role in rehabilitation.