Related Experiment Video
Updated: Jan 1, 2026
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Dynamic Visual Tests to Identify and Quantify Visual Damage and Repair Following Demyelination in Optic Neuritis Patients
Published on: April 14, 2014
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Mechanism of visual network dysfunction in relapsing-remitting multiple sclerosis and its relation to cognition
Gerald K Cooray1, Mathias Sundgren2, Tom Brismar1
1Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden; Department of Clinical Neurophysiology, Karolinska University Hospital, Stockholm, Sweden.
Summary
Brain network changes in relapsing-remitting multiple sclerosis (RRMS) are linked to visual processing issues and cognitive decline. Lower interhemispheric connectivity may impair cognitive function in RRMS patients.
Area of Science:
- Neuroscience
- Clinical Neurology
- Cognitive Science
Background:
- Relapsing-remitting multiple sclerosis (RRMS) is associated with visual event-related potential (ERP) abnormalities.
- The neurobiological underpinnings of these visual ERP changes and their link to cognitive deficits in RRMS remain unclear.
Purpose of the Study:
- To investigate if altered brain network function and connectivity contribute to visual ERP abnormalities in RRMS.
- To explore the relationship between these network changes and cognitive performance deficits in RRMS patients.
Main Methods:
- A cross-sectional study involving 72 RRMS patients and 89 healthy controls.
- Visual ERPs were recorded using EEG, and brain activity was modeled with Dynamic Causal Modelling.
- Cognitive function was assessed using a comprehensive neuropsychological test battery.
Main Results:
- Patients with RRMS exhibited reduced cortical connectivity, particularly in bottom-up and interhemispheric connections to the right lateral occipital complex.
- Interhemispheric connectivity in RRMS patients was significantly associated with cognitive dysfunction across multiple domains, including attention, executive function, and processing speed.
- No significant correlation between cortical network connectivity and cognitive function was observed in healthy controls.
Conclusions:
- Altered functional connectivity to higher cortical regions offers a neurobiological explanation for visual ERP changes observed in RRMS.
- Reduced interhemispheric connectivity in RRMS may be a key factor contributing to impaired cognitive function.
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