Roger K. Pitman, M.D.; Massachusetts General Hospital; PRMRP Investigator-Initiated Research Award

I've been doing work on post-traumatic stress disorder for about 30years now. One of the central problems in PTSD is these lasting very strong memories of the traumatic event that continue to trouble veterans and civilians for decades possibly after the event occurs. And we're trying to find out if there's a way that we can weaken the emotional distress that's accompanied with these lasting traumatic memories. It used to be thought that once one of these memories was formed it pretty much stayed that way for the duration and that the best you could do was to extinguish it. Which means learn to inhibit the response associated with the memory, for example the fear response. However, for the past 10 years there has been new research done in animal and in humans that suggest that it may be possible to actually reduce the strength of these memories so that a person actually has less strong memories rather than strong ones that he has to constantly inhibit. The research is call reconsolidation research and it's based on the idea that when you reactivate a memory by remembering it, it goes from a stable to unstable condition and that certain drug interventions given right after the reactivation may actually succeed in weakening the memory by preventing its reconsolidation. We've already done some research on propranolol which is an anti-adrenaline drug which we found has memory-weakening effects, but now we're looking at another drug called mifepristone which blocks the stress hormone cortisol and our data suggests that mifepristone has stronger memory-reducing effects than propranolol. So, we're hopeful that mifepristone may turn out to be even better at reconsolidation-blocking treatment for PTSD than propranolol. Eventually the goal is to have people with post traumatic stress disorder remember their traumatic event and then get a drug which is going to weaken the memory. Possibly over a series of a number of treatment sessions, they would come in, they would remember the traumatic event, they would get the drug, they would go home and they would do that on a weekly basis. And we would like to see if we could progressively, I don't think we'll ever eliminate the memory, but if we can progressively reduce the emotional distress associated with it by the post-reactivation drug intervention.