Conservation of structural brain connectivity in people with multiple sclerosis
Gerard Martí-Juan1, Jaume Sastre-Garriga2, Angela Vidal-Jordana2
1Neuroradiology Group, Vall d'Hebron Research Institute (VHIR), Barcelona, Spain.
Network Neuroscience (Cambridge, Mass.)
|December 30, 2024
Summary
Multiple sclerosis (MS) affects brain connectivity. This study found that a brain connectivity principle, balancing intra- and interhemispheric connections, holds true in people with MS, even with disease progression.
Area of Science:
- Neuroscience
- Neurology
- Medical Imaging
Background:
- Multiple sclerosis (MS) is a neurodegenerative disease impacting the central nervous system, notably the corpus callosum.
- Mammalian brain structural connectivity follows a conservation principle: an inverse relationship between intra- and interhemispheric connectivity.
- Understanding how MS affects this principle is crucial for comprehending disease mechanisms and cognitive impact.
Purpose of the Study:
- To investigate the validity of the brain connectivity conservation principle in individuals with MS.
- To explore the interaction between MS and the balance of intra- and interhemispheric connectivity.
- To correlate connectivity patterns with clinical and imaging markers in MS.
Main Methods:
- Analysis of a multicentric dataset comprising 513 people with MS and 208 healthy controls.
- Quantification of structural connectivity using various measures and graph analysis.
- Examination of the association between intra- and interhemispheric connectivity, white matter integrity, lesion load, and cognitive function (Symbol Digit Modalities Test).
Main Results:
- The inverse relationship between intra- and interhemispheric connectivity was confirmed in both healthy controls (r=0.38) and people with MS (r=0.35).
- Intrahemispheric connectivity significantly correlated with white matter fraction (r=0.48), lesion volume (r=-0.44), and Symbol Digit Modalities Test scores (r=0.25).
- The findings suggest that MS respects the brain's connectivity conservation principle, with compensatory shifts in connectivity.
Conclusions:
- The brain's structural connectivity conservation principle appears to be maintained in people with MS.
- Interhemispheric connectivity may decrease with increasing cognitive decline and disability, while intrahemispheric connectivity increases to compensate.
- These findings offer insights into the neural underpinnings of disability progression in MS.
