Essentials: Compulsive Behaviors & Deep Brain Stimulation | Dr. Casey Halpern

What It Covers

Neurosurgeon Dr. Casey Halpern explains how deep brain stimulation and focused ultrasound target the nucleus accumbens and prefrontal circuits to treat OCD, binge eating disorder, and addiction, while outlining the current 50% responder rate and the path toward non-invasive, AI-assisted psychiatric therapies.

Key Questions Answered

• •OCD Treatment Ladder: Roughly 30% of OCD patients fail both SSRIs/tricyclics and exposure response prevention therapy, making them candidates for surgical intervention. Deep brain stimulation and capsulotomy ablation currently achieve only a 50% responder rate, and even those responders retain symptomatic OCD, signaling a clear need for more precisely targeted approaches.
• •Nucleus Accumbens as Common Target: The ventral striatum, specifically the nucleus accumbens, gates reward-seeking behavior across OCD, binge eating disorder, addiction, and impulsivity. When this circuit is disrupted, individuals pursue rewards despite punishment or risk. Targeting this single region surgically may address compulsive behavior across multiple diagnoses rather than treating each condition separately.
• •Craving Cells as Biomarkers: Just as tremor cells in the subthalamic nucleus produce audible electrical signals matching tremor frequency, researchers have identified candidate "craving cells" in the nucleus accumbens. Detecting these signals with implanted electrodes during lab-provoked binge episodes allows closed-loop stimulation devices to intervene automatically at the precise moment craving escalates.
• •Non-Invasive Ultrasound Pathway: MRI-guided focused ultrasound is FDA-approved for tremor ablation without any incision or implanted electrode. Researchers are now testing whether the same technology can modulate rather than destroy tissue, and whether it can open the blood-brain barrier for targeted drug delivery, potentially creating a non-surgical route to treat psychiatric conditions once precise targets are confirmed.
• •Invasive Recording to Define Non-Invasive Targets: Stereoencephalography, placing sub-millimeter wires throughout the brain to map seizure circuits in epilepsy patients, is now being adapted to study OCD and depression. Pooling electrode data across large patient cohorts can identify consistent neural targets that would then translate into precise TMS or ultrasound treatment coordinates, eliminating the need for surgery in future patients.