Acute effects of deep brain stimulation on brain function in obsessive-compulsive disorder

Area of Science:

• Neuroscience
• Neuromodulation
• Psychiatry

Background:

• Refractory obsessive-compulsive disorder (OCD) can be treated with deep brain stimulation (DBS).
• Optimal DBS parameters lack identified neural markers.
• Understanding electrophysiological responses to varying DBS voltages is crucial for treatment optimization.

Purpose of the Study:

• To investigate sub-cortical electrophysiological responses to acute DBS at different voltages in OCD patients.
• To explore the relationship between DBS voltage and neural markers, specifically theta power and phase-stability.

Main Methods:

• Five OCD patients received DBS targeting the ventral anterior limb of the internal capsule at 3-5V.
• Electroencephalograms (EEG) and intracranial local field potentials (LFPs) were recorded.
• Analysis focused on theta power and phase-stability, known markers in DBS for OCD.

Main Results:

• Cortical theta power and phase-stability did not significantly increase with DBS voltage.
• Individualized therapeutic voltages showed DBS-induced theta power peaks.
• While LFP power generally increased with voltage, artifacts limited interpretation.
• Idiosyncratic effects were observed, with some patients showing acute and carry-over effects on theta power.

Conclusions:

• The study challenges the existence of a consistent dose-response relationship between DBS voltage and brain activity in OCD.
• Theta power warrants further investigation as a potential neurophysiological marker for personalized DBS voltage optimization in OCD.