Altered functional connectivity strength between structurally and functionally affected brain regions in visual snow...

Area of Science:

• Neurology
• Neuroimaging
• Neuroscience

Background:

• Visual snow syndrome (VSS) is a neurological disorder characterized by persistent visual disturbances.
• Previous research indicates structural and functional brain alterations in VSS patients.
• Understanding functional connectivity is crucial for VSS pathophysiology.

Purpose of the Study:

• To investigate resting-state functional connectivity between specific brain regions in VSS patients.
• To explore the relationship between functional connectivity, VSS symptoms, and oculomotor measures.
• To compare connectivity patterns in VSS patients with and without migraine.

Main Methods:

• Utilized 7 Tesla MRI to acquire high-resolution resting-state functional and anatomical images.
• Analyzed functional connectivity between predefined regions of interest in 40 VSS patients and 60 healthy controls.
• Correlated connectivity metrics with VSS symptom severity, intensity, disruptiveness, and oculomotor performance.

Main Results:

• VSS patients exhibited significantly higher connectivity between the supramarginal gyrus and lateral occipital cortex/fusiform gyrus.
• Lower connectivity was observed between the supramarginal gyrus and pallidum, and parahippocampal gyrus and lateral occipital cortex.
• Altered connectivity, particularly with the supramarginal gyrus, correlated with higher perceived disruptiveness of VSS.

Conclusions:

• Individuals with VSS display altered functional brain connectivity, characterized by increased cortical connectivity and decreased connectivity with deep grey matter and temporal cortices.
• These connectivity changes are associated with the subjective experience and disruptiveness of VSS.
• No significant differences in connectivity were found between VSS patients with and without migraine.