Limited cerebellar gradient extension in temporal lobe epilepsy with dystonic posturing

Area of Science:

• Neuroscience
• Epileptology
• Functional Neuroimaging

Background:

• Dystonic posturing (DP) is a frequent clinical manifestation in temporal lobe epilepsy (TLE).
• The cerebellum's role in DP generation within TLE remains under investigation.
• Understanding cerebellar functional connectivity alterations is crucial for TLE pathophysiology.

Purpose of the Study:

• To investigate alterations in cerebellar functional connectivity gradients in TLE patients.
• To compare these alterations between TLE patients with and without dystonic posturing (DP).
• To explore the contribution of cerebellar motor components to observed gradient changes.

Main Methods:

• Resting-state functional MRI data analyzed from 60 TLE patients and 32 healthy controls.
• TLE patients categorized into TLE with DP (TLE+DP) and TLE without DP (TLE-DP) groups.
• Independent component analysis used to assess cerebellar-cerebral functional integration and motor component contributions.

Main Results:

• TLE patients exhibited extended cerebellar principal gradients compared to controls.
• TLE+DP patients showed more limited cerebellar functional connectivity gradients, particularly in the ipsilateral cerebellum.
• Gradient alterations in TLE+DP patients involved greater contribution from cerebellar motor components.

Conclusions:

• Altered cerebellar functional connectivity gradients are present in TLE, indicating excessive functional segregation.
• Limited cerebellar gradients and increased ipsilateral motor function contribution characterize TLE with DP.
• Findings suggest a link between the ipsilateral cerebellum and contralateral dystonic posturing in TLE.