Human pulvinar stimulation engages select cortical pathways in epilepsy.

Area of Science:

• Neuroscience
• Neurology
• Epileptology

Background:

• The pulvinar is a potential neuromodulation target for posterior quadrant and temporal epilepsies.
• The pulvinar's large volume, multiple subnuclei, and extensive cortical connections present challenges for precise targeting.
• It is unclear if stimulating different pulvinar subregions yields distinct effects on temporal, occipital, and parietal cortices.

Purpose of the Study:

• To investigate the differential effects of electrical stimulation in distinct pulvinar subregions on occipital, temporal, and parietal cortical areas.
• To determine if selective pulvinar targeting can optimize neuromodulation for specific epilepsy types.

Main Methods:

• Single-pulse electrical stimulation was delivered to the pulvinar in twelve patients with drug-resistant epilepsy undergoing stereotactic EEG.
• Brain stimulation evoked potentials (BSPs) were measured and parameterized across occipital, temporal, and parietal cortical regions.

Main Results:

• Lateral pulvinar stimulation evoked significant responses in striate and extrastriate areas, decreasing with medial shift.
• Ventral medial pulvinar stimulation produced significant lateral temporal responses, diminishing with lateral pulvinar stimulation.
• Dorsomedial pulvinar stimulation evoked significant parietal responses with minimal occipital or lateral temporal effects.

Conclusions:

• Electrical stimulation of specific pulvinar subregions selectively influences distinct occipital, parietal, and lateral temporal areas.
• Precise targeting of pulvinar subregions is essential for maximizing seizure network engagement and individualizing treatment for posterior and temporal epilepsies.