2-Minute Neuroscience: Obsessive-Compulsive Disorder (OCD)
Obsessive-compulsive disorder, or OCD, is a condition characterized by obsessions and/or compulsions. Although the neuroscience of OCD is not completely understood, in this video I discuss one supported perspective on what happens in the brain to cause the obsessions and compulsions that occur in OCD.
For a more in-depth discussion of the neuroscience of OCD (on my website), click this link: https://neuroscientificallychallenged.com/posts/know-your-brain-obsessive-compulsive-disorder-ocd
TRANSCRIPT:
Obsessive-compulsive disorder, or OCD, is a condition characterized by obsessions and/or compulsions. Obsessions are recurrent unwanted thoughts, while compulsions are repetitive behaviors or mental acts often performed in response to obsessions, typically with the goal of reducing anxiety and discomfort. It’s important to note that OCD is often very distressing, and is not just a preference for orderliness, as the term is sometimes used to imply.
The neuroscience of OCD is not completely understood, and it’s likely that different neural circuits may be involved based on a person’s age and symptom profile, among other factors. One supported perspective on the neuroscience of OCD, however, points to a prominent role for circuits that connect the orbitofrontal cortex with a group of structures called the basal ganglia. According to this perspective, increased activity in the orbitofrontal cortex is associated with a heightened focus on concerns that spawn obsessive thoughts. When the orbitofrontal cortex is activated in response to something the brain perceives as a danger or concern, it communicates with the basal ganglia. A simplified version of basal ganglia circuitry suggests it consists of two opposing pathways: an excitatory pathway called the direct pathway, and an inhibitory pathway called the indirect pathway. When the orbitofrontal cortex sends a signal to the basal ganglia, it often leads to an action designed to alleviate the discomfort caused by the perceived danger; that action is mediated by the direct pathway. In a healthy person, the indirect pathway then inhibits further action. In someone with OCD, however, the direct pathway is over-excitable, drowning out the activity of the indirect pathway and causing a difficult time switching to a different behavior or turning focus away from the concern causing the discomfort. Thus, according to this model, overactivity in the orbitofrontal cortex and the direct pathway of the basal ganglia increases the occurrence of both obsessions and compulsions.
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