Rapid Effects of Intensive Therapy Seen in Brains of Patients with OCD

In a study that may significantly advance the understanding of how cognitive-behavioral therapy affects the brain, researchers have shown that significant changes in activity in certain regions of the brain can be produced with as little as four weeks of daily therapy in patients with obsessive-compulsive disorder (OCD). The discovery could have important clinical implications, according to principal investigator Sanjaya Saxena, M.D., Director of the Obsessive-Compulsive Disorders Program at the University of California, San Diego (UCSD) School of Medicine, whose findings are published on line this week in the journal Molecular Psychiatry.

“The study is exciting because it tells us more about how cognitive-behavioral therapy works for OCD and shows that both robust clinical improvements and changes in brain activity occur after only four weeks of intensive treatment," said Saxena.

OCD is an anxiety disorder in which individuals have unreasonable fears or worries that they try to manage through ritualized compulsive behaviors to reduce the anxiety. For example, a patient may experience the urgent need to engage in certain rituals, such as hand washing or repeatedly checking that the oven is off or the front door is locked.

Past studies using functional brain imaging studies of patients with OCD have demonstrated that elevated activity along the frontal-subcortical circuits of the brain decreases in response to treatment with serotonin reuptake inhibitor (SRI) medications or cognitive-behavioral therapy. However, clinical improvement of OCD symptoms was expected to require up to 12 weeks of behavioral therapy or medication treatment, the standard treatments for OCD. Only a handful of studies have looked at how therapy affects brain function, and all previous studies had examined changes over several months of treatment.

Saxena and colleagues at the David Geffen School of Medicine at UCLA made two novel discoveries in their study of 10 OCD patients and 12 control subjects.

“First of all, we discovered significant changes in brain activity solely as the result of four weeks of intensive cognitive-behavioral therapy,” said Saxena. “Secondly, these changes were different than those seen in past studies after a standard 12-week therapeutic approach using SRI medications or weekly behavioral therapy.”

The researchers obtained positron emission tomography (PET) scans of the ten OCD patients both before and after they received four weeks of a therapy known as “exposure and response prevention,” which gradually desensitizes patients to things that provoke obsessional fears or worries.

“This is the primary kind of therapy used for OCD. It teaches patients to pay attention to their internal experiences and tolerate scary thoughts without having to act on them,” said Saxena. “They learn that nothing terrible happens if they refrain from their usual compulsive behaviors.”