Biology & Treatments for Compulsive Behaviors & Binge Eating | Dr. Casey Halpern

Andrew Huberman introduces Casey Halpern as a neurosurgeon and researcher whose laboratory studies bulimia, binge-eating disorder, and obsessive-compulsive behaviors. The discussion emphasizes a circuit-level approach: alongside medication, behavioral treatment, and talk therapy, Halpern's group develops devices that can stimulate neural tissue involved in compulsive eating. The stated aim is not simply to suppress appetite, but to address episodes in which people continue eating despite recognizing that they should not or do not want to eat. The episode frames this work as an emerging frontier rather than an established universal treatment, and notes that the laboratory's work includes deep brain stimulation, surgical removal of small brain regions in some settings, and stimulation through the intact skull.

The introduction also places this research in a broader clinical context. Halpern's work involves movement disorders such as essential tremor, Parkinson's disease, and dystonias, while the conversation connects those conditions to compulsive and psychiatric symptoms. The specific example highlighted is a pilot study of responsive nucleus accumbens deep brain stimulation for loss-of-control eating. The nucleus accumbens is described as a bilateral region involved in dopamine release for motivated behavior, but the episode does not present that region as a simple one-to-one explanation for eating disorders. Instead, it presents stimulation and control of activity there as an experimental attempt to influence a difficult symptom while acknowledging that the field is still developing.

Halpern explains that neurosurgery covers the central nervous system and parts of the peripheral nervous system, not just deep brain stimulation. Neurosurgeons remove brain tumors, treat aneurysms, care for traumatic brain and spine conditions, perform disc and lumbar-fusion procedures, and treat nerve disorders such as carpal tunnel syndrome. The field has increasingly divided into subspecialties. Halpern works in stereotactic and functional neurosurgery, where his routine work centers on deep brain stimulation and focused ultrasound, including transcranial focused ultrasound for ablation. At the time of the interview, he says focused ultrasound had FDA approval for tremor.

Halpern distinguishes structural operations from stimulation-based therapy. Removing a tumor or reaching an aneurysm requires finding a safe surgical path and managing the patient's recovery, whereas deep brain stimulation uses a thin insulated wire placed in a disease-relevant region. The wire contains multiple small contacts and connects to a battery or pulse generator resembling a pacemaker. The operation implants the delivery system, but the treatment comes from electrical stimulation delivered through the contacts. Halpern compares this arrangement to implanting a tool that administers a medication, with electricity delivered to a very small brain region instead of a chemical compound. This distinction explains why his surgical practice and his laboratory research both focus on modulating brain physiology, not only on removing or repairing structure.

Huberman asks whether familiar textbook stories about stimulation causing rage or uncontrollable laughter are clinically real. Halpern says electrodes placed in a small target can affect nearby regions within a few millimeters, producing brief effects such as laughter or panic. The effect can be turned off, and an apparent side effect can sometimes become therapeutically useful. He gives the example of patients with Parkinson's disease whose tremor treatment coincides with improvements in gambling problems, mood, or compulsive and impulsive symptoms. He cautions implicitly against reducing these outcomes to a single mechanism: mood may improve because tremor improves, while stimulation may also reach limbic circuits involved in emotion. The clinical observations therefore guide possible treatments, but they do not by themselves establish why every symptom changes.

For Halpern, the most consistent and striking effect is the immediate reduction of tremor when stimulation is delivered in the clinic. He describes this experience as the event that drew him toward neurosurgery and says he hopes to develop comparable therapies for other symptoms, including the urge to consume something delicious but dangerous or unhealthy, drug-related urges, and compulsions associated with obsessive-compulsive disorder. He reports that some brain-related psychiatric symptoms can also improve immediately, but the conversation does not claim that all psychiatric disorders respond in the same way or that stimulation is broadly ready for routine use. The contrast with medication is that drugs can have delayed and difficult-to-explain effects; Huberman specifically notes that even the reasons selective serotonin reuptake inhibitors work are not fully understood, while Halpern identifies timing as a continuing challenge.

Huberman then uses his own experience to open a discussion of OCD and related circuits. He describes narrow, persistent focus that can be adaptive in some situations and less adaptive in others, as well as a childhood throat-clearing tic that produced relief when performed and resurfaced occasionally with fatigue. He presents these experiences as personal observations rather than a diagnosis, and uses them to suggest that compulsive or overexcited circuits may exist in everyone in different forms. Halpern is asked to explain what OCD is, but the excerpt ends at the start of that question. As a result, this portion establishes the clinical and personal motivation for the topic without yet supplying Halpern's definition, diagnostic boundaries, or treatment guidance.

Halpern begins with an important qualification: he treats only a small number of people with severe OCD each year using deep brain stimulation, while his laboratory studies how to improve that treatment. He distinguishes this surgical perspective from that of a psychiatrist who sees people with OCD every day. His stated responsibility is to understand where obsessions arise and how to interrupt the compulsion linked to them, but he also stresses the gap between the consistency of stimulation for tremor and the less predictable benefit for OCD. The operative risk may be comparable, yet the expected benefit is not as strong, which understandably makes patients and referring psychiatrists cautious.