Taking the edge off ugly memories
Posttraumatic stress disorder is in part a function of keen memory: An unpleasant recollection may be so vivid that it causes disabling fear and anxiety. What if you could manipulate the memory and take away its heart-pounding, sweat-inducing intensity? Researchers are homing in on a way to do just that.
Technology Review (May-June 2009) reports that this new approach is based on a theory about the way memory works, called memory reconsolidation, which is gaining currency among neuroscientists: “The idea is that after someone calls up a memory, it has to be stored in the brain anew. During this process, the brain is in a changeable state.” Psychologists are learning that administering a drug during this period can take the edge off PTSD-triggering memories.
“It seemed like science fiction,” says Alain Brunet, a Canadian psychologist who has had success with the method in clinical trials. “If someone is traumatized, you ask them to recall the memory, give them a pill, and the [emotional] strength of the memory is weakened.”
In his trials, Brunet used propranolol, a drug that is used to treat high blood pressure but also blocks the action of the stress hormone epinephrine in the amygdala, a part of the brain that’s key to storing the emotional component of memory.
His findings, though preliminary, are good news for people suffering from PTSD, including the 15 percent of U.S. troops returning from Afghanistan and Iraq who show signs of the disorder. Brunet has successfully treated soldiers as well as survivors of rapes and car accidents.
The evolving understanding of memory reconsolidation, if it’s correct, may have implications far beyond PTSD: It may fundamentally reshape the way we think about memory and, according to Technology Review, “could be used to treat a variety of anxiety disorders and addictions.”