Essentials: The Science & Treatment of Obsessive Compulsive Disorder (OCD)

This Essentials episode starts from the mechanics of the disorder rather than its stereotype. Obsessions are intrusive and unwanted; compulsions briefly relieve them and then reinforce them, which is the loop that makes OCD self-sustaining. Huberman puts prevalence at roughly 2.5 to 4 percent of people and notes OCD ranks around seventh among the most debilitating illnesses of any kind, not just psychiatric ones. He sorts the presentations into three bins — checking, repetition and order — and stretches the third one further than most listeners will expect: order covers symmetry and cleanliness, but also incompleteness (being unable to walk away from a table setting or a sentence that isn't right) and disgust or contamination, which is where hand-washing comes from.

The neuroscience section is the spine of the episode. The circuit implicated is the cortex, the striatum and basal ganglia (go and no-go action selection), and the thalamus, wrapped in the thalamic reticular nucleus that gates which sensory information reaches conscious perception. Evidence comes from provocation studies where subjects with contamination obsessions are handed a towel carrying someone else's sweat while being scanned by fMRI or PET; the cortico-striato-thalamic loop is what becomes more metabolically active. SSRIs quiet both the symptoms and that circuit — yet Huberman is blunt that there is very little evidence the serotonin system itself is disrupted in OCD, and calls that mismatch between what treats a disorder and what causes it a recurring theme in psychiatry.

On diagnosis he reads from the Yale-Brown Obsessive Compulsive Scale, the Y-BOCS, which runs dozens of pages and checklists aggressive, contamination, sexual, saving and moral obsessions as present or absent, currently and in the past. Its real purpose, he argues, is to force the patient to name the precise catastrophic fear driving the obsession, because that specificity is what exposure therapy needs to work.

The treatment comparison draws on the work of Dr. Helen Blair Simpson of Columbia. Her protocol is two planning sessions followed by fifteen exposure sessions, twice a week or more, over ten to twelve weeks, pairing in-person exposure with ritual prevention. In the comparison Huberman describes, placebo did not meaningfully reduce symptoms, SSRIs did, and CBT did far more — severity scores fell from about 25 to about 11 by four weeks — while adding SSRIs to CBT produced no further decrease. He closes on the other candidates: a Blair Simpson study found smoked cannabis, THC or CBD, had little acute impact on OCD symptoms; TMS aimed at motor and supplementary motor areas shows promise in small cohorts, especially combined with drugs or CBT; mindfulness appears to help indirectly, by improving engagement with CBT homework rather than by relieving symptoms directly; and inositol is the nutraceutical he thinks deserves more systematic study.