Two teams of researchers have pinpointed some of the neural circuitry that underlies compulsive grooming behaviors. The discoveries, reported in Science on Thursday, could guide new treatments for people with obsessive-compulsive disorder, autism, and other conditions that exhibit symptoms of repetitive and compulsive actions.

Using so-called optogenetics techniques, which precisely control neuron activity with light, one of the groups induced repetitive grooming behaviors by stimulating a neural circuit known to be overactive in OCD patients. The obsessive grooming behaviors persisted even after the light stimulation stopped.