Shaping Early Reorganization of Neural Networks Promotes Motor Function after Stroke

Area of Science:

• Neuroscience
• Neurology
• Rehabilitation Medicine

Background:

• Cortical reorganization driven by neural plasticity is crucial for stroke recovery.
• Early intervention post-stroke is vital for functional restoration.
• Intermittent theta-burst stimulation (iTBS) is a non-invasive brain stimulation technique.

Purpose of the Study:

• To investigate if iTBS enhances motor cortex plasticity and promotes functional recovery early after stroke.
• To explore the neural mechanisms underlying the effects of iTBS on motor recovery using fMRI.

Main Methods:

• A sham-controlled, pseudo-randomized study involving 26 first-ever stroke patients with hand motor deficits (1-16 days post-stroke).
• Patients received iTBS over the ipsilesional primary motor cortex (M1) or a control vertex site prior to physiotherapy for 5 consecutive days.
• Hand motor function, cortical excitability, and resting-state fMRI were assessed before and after the intervention period.

Main Results:

• The M1-stimulation group showed significantly greater recovery of grip strength compared to the control-stimulation group.
• Higher motor network connectivity correlated with better motor outcomes.
• Motor network connectivity decreased in the control group but not in the M1-stimulation group, suggesting iTBS mitigated motor network degradation.

Conclusions:

• Adding iTBS to prime physiotherapy may enhance early motor recovery after stroke.
• iTBS appears to interfere with motor network degradation, potentially by alleviating post-stroke diaschisis.
• The findings highlight the potential of iTBS as an adjunct therapy in stroke rehabilitation.