Brave New Memories

It’s normal to be a bit anxious before talking in front of a crowd, but for some people the prospect is far more daunting. Suffering from social anxiety disorder, they face a debilitating condition that affects everything from speaking up at meetings to dating.

One form of treatment is cognitive behavioral therapy, used not to delve into underlying psychological issues but to confront and overcome phobias. To treat, say, anxiety about speaking in public, the therapy might involve trying public speaking in increasingly difficult but controlled circumstances, learning that it’s possible to do so without frightful consequences. It’s a fairly successful way to address the problem, but of course it doesn’t always work.

Now two College of Arts and Sciences psychology professors and their colleagues have shown that such therapy can be enhanced with a drug that helps create stronger memories specifically about the extinction of fear. The drug, an antibiotic called D-cycloserine (DCS), was originally developed to combat tuberculosis, but was later found to directly affect receptors in the brain involved in learning — and extinguishing — fear. When Michael Otto, a professor, and Stefan Hofmann, an associate professor, read about that effect, they were intrigued with its potential for enhancing the cognitive behavioral therapy they employ at BU’s Center for Anxiety and Related Disorders.

To test the theory, they recruited patients who came to the center for treatment of social anxiety disorder, together with collaborators at two other sites. In the randomized double-blind study, some patients were given a 50mg dose of DCS before beginning each of the five therapy sessions, others a placebo. The small dose, which is only a 10th the usual daily dose used for treating tuberculosis, minimized the chances that participants would be aware of the effects.

After five sessions, patients reported their anxiety levels, and the difference was clear-cut: the ones who took DCS had significantly less social anxiety than those who didn’t. “It looks like the DCS aids the consolidation of the memory,” Otto says. It’s also clear that DCS is “not an anti-anxiety medication — it has no apparent effect on anxiety,” Hofmann notes. “It’s not that you feel different while you’re on the DCS during the session; it’s the memories [of the treatment sessions] that are different.”

Currently the team is doing similar research with patients who suffer from panic disorder, and although the results aren’t in yet, there are indications the treatment works for them as well. “We had a patient saying, ‘I had a crystal clear memory of sitting here with you last week when I was in the phobic situation, and so I reacted differently,’” Otto says. “I usually don’t hear that kind of description, and we wonder if that’s a manifestation of how the DCS makes it feel for patients, so that those memories are more accessible.”

The next step is to do a trial with the standard 12-session cognitive behavioral therapy.

“As we continue to validate this,” Otto says, “we will have an extra treatment for people who have been treatment-resistant, people who have not received enough help. If a person took the 12 sessions and didn’t benefit, this might be the next step. It gives us another tool in the tool chest.” And that’s good news, considering that anxiety disorders are third, after substance abuse and depression, Hofmann says, among psychological disorders in America.