Obsessive compulsive disorder

Healthy volunteers and patients with obsessive-compulsive disorder learning a task from experience alone tend to repeat actions that lead to rewards. They are poor at learning predictive models, but their use of these models is strongly increased when explicit information is provided.

Intravenous infusion of ketamine rapidly reduces obsessive-compulsive disorder symptoms. Here, the authors show in mice that ketamine acts by increasing activity in a fronto-striatal circuit that causally controls compulsive grooming behaviour.