Globus Pallidus Externus alpha-Band Activity Decreases After Deep Brain Stimulation in Clinically Responsive Obsessive-Compulsive Disorder Patients

AI Summary

ALIC deep brain stimulation produced a 40% mean reduction in OCD symptoms at six months.
Local field potentials recorded from ventral GPe showed a significant bilateral decrease in alpha activity with clinical response.
The single non-responder lacked any alpha decrease, implying GPe alpha-power reduction may serve as a biomarker of sustained response.

TL;DR (AI Generated)

BACKGROUND: Deep brain stimulation (DBS) of the anterior limb of the internal capsule (ALIC) is an effective treatment for severe obsessive-compulsive disorder (OCD).

We consistently stimulated dorsal lead contacts in the ALIC white matter while recording LFP from the ventral lead contacts in the grey matter of the anterior globus pallidus externus (GPe), a key node in the basal ganglia nonmotor indirect pathway.

Basic summary

Neuromodulation. 2026 Sep 24:S1094-7159(26)01359-0. doi: 10.1016/j.neurom.2026.09.006. Online ahead of print.

ABSTRACT

BACKGROUND: Deep brain stimulation (DBS) of the anterior limb of the internal capsule (ALIC) is an effective treatment for severe obsessive-compulsive disorder (OCD). Identifying brain readouts of a positive response may guide further DBS optimization.

MATERIALS AND METHODS: We measured local field potential (LFP) changes from bilateral DBS leads in ten patients with OCD who were implanted at a uniform tractographic network target derived from prior DBS responders. We consistently stimulated dorsal lead contacts in the ALIC white matter while recording LFP from the ventral lead contacts in the grey matter of the anterior globus pallidus externus (GPe), a key node in the basal ganglia nonmotor indirect pathway.

RESULTS: After six months of DBS, OCD symptoms decreased by 40% on average across patients, along with a significant decrease in α-activity across both hemispheres. Only one patient did not have an improvement in symptoms, and this was also the only patient who never exhibited a decrease in α in either hemisphere.

CONCLUSIONS: Our findings suggest that therapeutic ALIC DBS coincides with a stable decrease in limbic-cognitive GPe α-power, which should be further investigated as a potential biomarker of sustained response.

PMID:43033174 | DOI:10.1016/j.neurom.2026.09.006

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