Resting functional connectivity between the hemispheres in childhood absence epilepsy

Area of Science:

• Neuroscience
• Epilepsy Research
• Brain Imaging

Background:

• Childhood absence epilepsy (CAE) mechanisms affecting neural networks between seizures are unclear.
• Existing EEG-fMRI studies show bilateral synchronous activity during seizures.

Purpose of the Study:

• To investigate if abnormal bisynchrony in CAE extends to the interictal period.
• To use resting-state functional connectivity (BOLD) to assess interhemispheric connectivity in CAE.

Main Methods:

• Recorded EEG-fMRI data from 16 patients with CAE and 16 controls.
• Compared interhemispheric resting functional connectivity between hemispheres using predefined ROIs and a paired-voxel approach.
• Assessed whole-brain connectivity for regions with increased interhemispheric connectivity.

Main Results:

• Significantly increased interhemispheric resting functional connectivity was found in the lateral orbitofrontal cortex of CAE patients compared to controls.
• This enhanced connectivity in the lateral orbitofrontal cortex was consistent across all three analysis methods.

Conclusions:

• Patients with CAE exhibit abnormal increased interhemispheric connectivity in seizure-related regions, persisting between seizures.
• The lateral orbitofrontal cortex is implicated in CAE pathophysiology.
• Resting functional connectivity analysis shows potential as a biomarker for understanding interictal brain function in CAE.