Brain complexity in stroke recovery after bihemispheric transcranial direct current stimulation in mice

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Biomedical Engineering

Background:

• Stroke is a major cause of global disability.
• Non-invasive brain stimulation, particularly transcranial direct current stimulation (tDCS), shows promise for stroke recovery.
• Bihemispheric tDCS offers a novel approach by modulating brain excitability in both hemispheres.

Purpose of the Study:

• To investigate the effects of bihemispheric transcranial direct current stimulation (btDCS) on stroke recovery in mice.
• To analyze brain activity complexity using the Entropy index.
• To correlate brain activity changes with behavioral outcomes.

Main Methods:

• Stroke was induced in mice, followed by btDCS treatment.
• Local field potentials were recorded to measure brain activity.
• Grip strength was assessed using a behavioral test.
• Signal complexity was quantified using the Entropy index.

Main Results:

• Stroke mice exhibited higher brain signal Entropy compared to healthy controls.
• btDCS treatment reduced Entropy in both healthy and stroke mice.
• A negative correlation was observed between Entropy and Grip Strength, indicating reduced complexity with improved motor function.
• btDCS demonstrated a more pronounced effect on Entropy reduction in stroke mice.

Conclusions:

• The Entropy index effectively characterizes brain complexity changes associated with stroke and recovery.
• Bihemispheric transcranial direct current stimulation modulates brain rhythms in a stroke model.
• btDCS presents a potential therapeutic strategy for stroke rehabilitation.