Frequency-specific alterations in brain connectivity induced by pulvinar stimulation.

Area of Science:

• Neuroscience
• Epileptology
• Neurosurgery

Background:

• Deep brain stimulation (DBS) is an emerging therapy for drug-resistant epilepsy.
• DBS may benefit patients by reducing excessive brain functional connectivity (FC).
• Stereoelectroencephalography (SEEG) electrodes in the thalamus (pulvinar medialis, PuM) are used in presurgical evaluations.

Purpose of the Study:

• To investigate the impact of different stimulation frequencies on brain FC.
• To determine if specific frequencies are more effective in modulating FC in drug-resistant epilepsy patients.

Main Methods:

• SEEG was employed to study PuM stimulation effects across 1-200 Hz in 14 epilepsy patients.
• Functional connectivity (FC) was assessed using nonlinear correlation coefficient (h2) and node strength calculations.

Main Results:

• Stimulation at 10 Hz and >90 Hz reduced FC; 20-80 Hz increased FC.
• FC modulation extended beyond the epileptogenic zone, affecting all brain lobes.
• Parietal, insular, and subcortical regions showed significant changes with high-frequency stimulation.

Conclusions:

• High-frequency stimulation shows potential for decreasing interictal FC in epilepsy.
• Intermediate frequencies may exacerbate FC, necessitating caution.
• PuM stimulation influences FC patterns, supporting high-frequency thalamic stimulation for epilepsy management.