Relating brain damage to brain plasticity in patients with multiple sclerosis

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Neuroimaging

Background:

• Increasing pathology in multiple sclerosis (MS) is thought to drive disability progression.
• However, observed improvements with practice suggest preserved brain plasticity in MS patients, even with significant brain damage.

Purpose of the Study:

• To investigate brain plasticity mechanisms underlying visuomotor performance improvements in MS patients using functional magnetic resonance imaging (fMRI).
• To correlate these plasticity measures with indicators of microstructural brain damage.

Main Methods:

• Functional MRI (fMRI) and structural MRI were used to scan 23 MS patients and 12 healthy controls.
• Brain activity was measured during initial and extended (2-week) practice of a visuomotor task.

Main Results:

• MS patients demonstrated performance improvements comparable to controls with practice, irrespective of pathology.
• Distinct patterns of brain activation changes related to practice-induced improvements were observed between MS patients and controls.
• Short-term improvements in MS patients correlated with lower activation in specific brain regions, while long-term improvements in controls correlated with reduced activation in the visual cortex.

Conclusions:

• Visuomotor practice induces brain plasticity in MS patients, even with substantial cerebral pathology.
• MS patients utilize different cognitive systems for plasticity compared to healthy controls.
• Findings support the feasibility of recovery-oriented strategies for MS patients, countering the notion of failed plasticity due to pathology.