Huberman LabBiology & Treatments for Compulsive Eating & Behaviors | Dr. Casey Halpern
CHAPTERS
- 0:00 – 7:00
Intro to Episode and Guest: Brain Circuits for Compulsive Eating
Huberman introduces Dr. Casey Halpern, a neurosurgeon whose lab focuses on bulimia, binge eating disorder, and obsessive-compulsive behaviors. He frames the discussion as a look at cutting-edge neuromodulation—especially deep brain stimulation—for both eating and movement disorders.
- •Halpern is Chief of Neurosurgery at UPenn and specializes in stereotactic and functional neurosurgery.
- •His lab targets neural circuits underlying compulsions rather than relying only on drugs or talk therapy.
- •Recent Nature Medicine paper: responsive nucleus accumbens DBS for loss-of-control eating.
- •Episode also covers DBS for Parkinson’s, essential tremor, and dystonia.
- •Goal: understand how brain circuits drive behavior and how we can precisely modify them.
- 7:00 – 18:40
What Neurosurgeons Do: Structure vs. Circuit Modulation
Halpern explains the broad scope of neurosurgery, from tumors and aneurysms to spine and nerve disorders. He contrasts structural surgeries with functional procedures like DBS and focused ultrasound that directly alter brain activity to treat symptoms.
- •Neurosurgeons treat the entire central and peripheral nervous system: tumors, aneurysms, trauma, spine, nerve entrapments.
- •Functional subspecialty focuses on deep brain stimulation and focused ultrasound.
- •DBS implants an electrode and pulse generator; the therapy is the electrical pattern, not the hardware itself.
- •Focused ultrasound can create precise lesions noninvasively and is FDA-approved for tremor.
- •Functional work is more about physiology and circuits than anatomy alone.
- 18:40 – 35:40
Immediate Effects of Brain Stimulation: From Tremor Relief to Emotion
Responding to Huberman’s question about 'outrageous' brain effects, Halpern describes transient laughter, panic, or mood changes when stimulating near certain regions. He emphasizes how observing side effects led to new uses for DBS beyond movement disorders.
- •Stimulating a few millimeters off-target can temporarily induce laughter, panic, or other brief phenomena.
- •Such side effects sometimes prove therapeutic and reveal new targets (e.g., mood, compulsivity).
- •Classic DBS for tremor can abolish 20-year tremors immediately in the clinic.
- •This rapid, reproducible effect inspired Halpern to pursue neurosurgery.
- •Similar immediate changes can occur for psychiatric-like symptoms in some DBS patients.
- 35:40 – 47:40
Defining OCD and Its Treatment Landscape
Halpern outlines how OCD ranges from helpful traits to debilitating disorder and reviews medications and behavioral therapies. He notes that about 30% of patients remain severely affected despite treatment and are the ones considered for DBS or lesion procedures.
- •OCD exists on a spectrum; some 'obsessive' traits can be adaptive (e.g., for surgeons, CEOs).
- •First-line treatments: SSRIs, tricyclics, and exposure/response-prevention (ERP) therapies.
- •Approximately 30% of patients remain significantly symptomatic despite optimal pharmacologic and behavioral care.
- •Surgical options include DBS and capsulotomy (lesioning white matter tracts).
- •DBS for OCD currently yields about a 50% responder rate; responders are improved but not symptom-free.
- •Research goal: make circuit-targeted DBS more precise and symptom-specific.
- 47:40 – 58:20
OCD Circuits: Frontal Cortex, Basal Ganglia, and Ventral Striatum
The discussion shifts to the brain regions implicated in OCD and compulsive behavior. Halpern describes dysregulated frontal cortical areas and their projections to dorsal and ventral striatum, including the nucleus accumbens, as central to gating urges versus risks.
- •Key cortical regions: orbitofrontal cortex (OFC) and prefrontal cortex (PFC) show dysregulated (hyper or hypo) activity in OCD.
- •Basal ganglia (caudate/putamen/dorsal striatum) link to ventral striatum (including nucleus accumbens).
- •Ventral striatum helps gate reward-seeking versus risk, analogous to rats enduring foot shocks for food.
- •Loss of balanced judgment—taking repeated risks for little reward—underlies OCD and addictive-like behaviors.
- •Compulsive checking, washing, binge eating, and drug seeking share this 'urge despite risk' profile.
- 58:20 – 1:11:40
Personal Anecdotes: Tics, Stimulants, and Superstitions
Huberman shares his childhood throat-clearing tic and a college episode where stimulants precipitated a transient 'knock-on-wood' superstition. Halpern uses these to illustrate how vulnerable brains can be to environmental and pharmacologic hits.
- •Childhood tics (like throat clearing or blinking) are common, often transient, and can reemerge under fatigue or stress.
- •A stimulant (ephedrine-like) plus caffeine triggered a short-lived, compulsive superstition in Huberman.
- •Halpern suggests stimulants can overdrive prefrontal/OFC circuits and unmask latent OCD-like tendencies in vulnerable people.
- •College is a classic time for psychiatric symptoms to emerge due to stress and new exposures.
- •These anecdotes highlight how 'normal' brains can tip into compulsive patterns under the right conditions.
- 1:11:40 – 1:22:40
Nucleus Accumbens: From Rodent Reward Hub to Human Target
The conversation centers on the nucleus accumbens as a hub for reward, motivation, and compulsion. Halpern describes rodent studies showing how high-fat diets rapidly alter accumbens function and set the stage for loss-of-control behaviors.
- •Nucleus accumbens is heavily interconnected and functions as a key reward/compulsion gate.
- •In mice, two weeks of high-fat food exposure measurably change accumbens activity patterns.
- •Some circuit elements become hyperactive, others hypoactive; the core issue is dysregulation, not a simple up/down shift.
- •Repeated exposure to highly salient rewards (food, drugs) likely leads to habit formation and compulsive pursuit.
- •Halpern’s team uses these rodent findings to design human DBS targets and stimulation paradigms.
- 1:22:40 – 1:38:40
Binge Eating Disorder, Loss-of-Control Eating, and Obesity
Halpern clarifies definitions of binge eating versus loss-of-control eating and how they relate to obesity. He describes his NIH-funded DBS trial for patients with severe binge eating who failed gastric bypass, aiming to restore control via accumbens modulation.
- •Binge eating disorder is the most common eating disorder, affecting ~3–5% of the population.
- •Clinically defined binges usually occur once per day in severe cases, but loss-of-control eating can occur many times weekly.
- •Not everyone with obesity has a compulsive eating problem; perhaps ~20% do, but that subset is still massive.
- •Halpern’s trial enrolls patients with both obesity and demonstrable loss-of-control eating who failed gastric bypass.
- •Target is the nucleus accumbens, where a 'craving signal' predicts imminent loss-of-control episodes.
- •Goal is to normalize circuit function rather than suppress all appetite or reward.
- 1:38:40 – 1:56:40
Designing Human DBS Trials: Finding 'Craving Cells' in Surgery
Halpern explains how intraoperative recordings are used to locate craving-related neuronal activity in the nucleus accumbens. Patients are shown personalized high-craving food images in the OR while single neurons and local field potentials are recorded.
- •Approach parallels Parkinson’s DBS: locate 'tremor cells' in subthalamic nucleus, but here it's 'craving cells' in accumbens.
- •Patients fast before surgery and view pictures of foods they have rated as highly craved.
- •Electrophysiology: microelectrodes record single-unit activity; macro contacts record population local field potentials.
- •Trial feasibility constraints limit how long surgeons search for craving-related neurons.
- •Intraoperative stimulation helps map regions that both modulate craving and elevate mood without adverse side effects.
- •Intra-op CT plus tractography verify electrode position and connectivity to prefrontal control circuits.
- 1:56:40 – 2:15:20
Responsive Stimulation: Blocking Craving → Binge Transitions
The focus shifts to responsive, closed-loop DBS that triggers only when pathological activity appears. Halpern outlines how craving is operationalized, why brief positive mood induction might interrupt binge chains, and what mouse data suggest about timing.
- •Craving is used as the primary analog to tremor: a subjective, but behaviorally relevant, pre-binge state.
- •Many patients report 'pre-meal negative affect' (stress, low mood) right before binges; the binge relieves it.
- •Responsive DBS detects accumbens signatures of this state and delivers 5–10 seconds of stimulation to elevate mood and disrupt the cycle.
- •In mice, intermittent, signal-triggered stimulation robustly blocks binge behavior and appears to normalize the aberrant signal over time.
- •Continuous stimulation leads to tolerance and loss of benefit, underscoring the need for episodic approaches in episodic disorders.
- •Halpern hopes similar real-time interventions will translate to OCD, addiction, and possibly suicidality.
- 2:15:20 – 2:38:00
Anorexia, Shared Circuits, and Future DBS Directions
Halpern argues that anorexia and certain forms of obesity are more similar than they appear, both involving compulsive eating-related behaviors despite risk. He reviews preliminary DBS work for anorexia and his plans to adapt responsive approaches.
- •Anorexia has the highest mortality of all psychiatric disorders, via both suicide and metabolic failure.
- •Phenotypically opposite conditions—severe obesity from overeating and anorexia from undereating—can both stem from compulsive risk-taking around food.
- •Early DBS studies in nucleus accumbens and area 25 show promising but preliminary results in anorexia.
- •Halpern’s group is conceptualizing an accumbens-based responsive DBS trial aimed at detecting and interrupting the compulsion to restrict food.
- •Grant funding and regulatory approval make progress slow—often years from concept to first patient.
- •Noninvasive approaches could be especially important in severely underweight patients, but targets must first be discovered invasively.
- 2:38:00 – 2:54:00
Noninvasive Neuromodulation: TMS, Focused Ultrasound, and Limits
They discuss the current clinical status of TMS and MR-guided focused ultrasound. Halpern supports integrating neurosurgical insight into noninvasive methods but insists that circuit-level knowledge from invasive work is essential to make them precise.
- •TMS is FDA-approved for depression, OCD, and nicotine addiction; typical targets are frontal cortical areas.
- •TMS has limited depth but can influence deeper structures indirectly via strongly connected cortical hubs.
- •Focused ultrasound is FDA-approved to create precise lesions for tremor, with robust clinical effects.
- •Research is underway to use ultrasound for neuromodulation and blood–brain barrier opening.
- •Major limitation: for psychiatric and eating disorders, we still lack well-validated lesion or modulation targets.
- •Future: use invasive recordings (e.g., stereo-EEG in epilepsy and psychiatric patients) to define optimal targets and circuits, then translate to TMS/ultrasound.
- 2:54:00 – 3:07:00
Using Epilepsy Techniques to Map Psychiatric Circuits
Halpern describes how stereo-EEG—multiple depth electrodes used in epilepsy workups—is being repurposed to study depression and OCD circuits. This approach could eventually inform both DBS and noninvasive treatments.
- •Stereo-EEG places many fine electrodes across cortical and subcortical regions to localize seizure onset zones.
- •These procedures are now routine and relatively safe, providing a ready platform for psychiatric research.
- •UCSF and Baylor have used stereo-EEG to map depression networks and assess stimulation effects.
- •Halpern and collaborators are seeking FDA approval to apply similar methods to OCD.
- •Data from such studies could define consistent, clinically meaningful targets suitable for DBS or even focused ultrasound lesions.
- •Conceptually, this is the bridge from exploratory invasive mapping to scalable, noninvasive therapies.
- 3:07:00 – 3:27:00
Awareness, Behavior Therapy, and the Limits of Willpower
Huberman and Halpern explore the role of self-awareness in preventing binges or compulsive acts. Halpern values awareness and CBT-style strategies but explains why, in the most severe cases, awareness is present yet insufficient.
- •Many therapies (CBT, ERP) aim to heighten awareness of triggers and teach alternative responses.
- •Improved awareness can meaningfully help milder to moderate cases and is often first-line.
- •In Halpern’s most treatment-resistant patients, awareness is maximal—they know exactly what's happening—yet they still can't stop.
- •In lab settings with video, eye tracking, and one-way mirrors, patients binge despite knowing they are being observed for that behavior.
- •CBT benefits often fade when therapy stops, suggesting underlying circuits remain unchanged.
- •Responsive DBS aspires to restore the capacity to exert control at precisely those critical moments when awareness alone fails.
- 3:27:00
Neurosurgeon Mindset: Training, Stress, and Personal Tools
The final segment turns to neurosurgeons’ characteristic calm and how they cope with intense training and responsibility. Halpern shares his own struggles with stress, weight gain during residency, and the physical and mental tools he now uses.
- •Neurosurgeons are often perceived as unusually calm and unflappable; training both selects for and amplifies this trait.
- •Residency involves long hours, high acuity, and periods of relative isolation on call; historically even more so than today.
- •Halpern describes gaining weight, using sugary coffee to stay awake, and then later reclaiming his health through consistent stair-climbing and gym time.
- •He emphasizes the value of supervised strength training (including deadlifts) for posture and resilience, when done carefully.
- •He now uses nightly guided meditation via an app as a simple but reliable tool for stress management and sleep.
- •He underscores the importance of making limited off-duty time truly high-quality with family and friends.
