Dissociated multimodal hubs and seizures in temporal lobe epilepsy

Area of Science:

• Neuroscience
• Epilepsy Research
• Brain Imaging

Background:

• Resting-state brain connectivity is disrupted in temporal lobe epilepsy (TLE).
• Hub regions, like the posterior default mode network (DMN), are particularly affected.
• The interplay between functional and anatomical connectivity and its relation to seizure frequency in TLE is not fully understood.

Purpose of the Study:

• To investigate the relationship between functional and anatomical hub connectivity in TLE.
• To clarify how these connectivity measures relate to seizure frequency.

Main Methods:

• Diffusion and resting-state functional MRI were used to assess connectivity in 49 TLE patients and 23 controls.
• Within-module and between-module hub connectivity were analyzed across brain modules.
• Measures included DMN disintegration (DD) and anatomical between-module connectivity.

Main Results:

• TLE patients showed reduced DMN functional integrity and increased posterior hub connections to other modules.
• Global anatomical between-module connectivity was decreased in TLE.
• Higher DD and anatomical between-module connectivity were associated with increased seizure frequency, indicating a complex interaction.

Conclusions:

• Evidence suggests dissociated anatomical and functional hub connectivity in TLE.
• Shifts in functional connectivity, loss of anatomical integration, and their interaction contribute to increased seizure frequency.