Erasing the Pain of the Past

Scientists Are Developing Drugs That Could Eliminate Traumatic Events From Our Memories


March 20, 2007 — "I'd take it in a second," said Sgt. Michael Walcott, an Iraq War veteran, referring to an experimental drug with the potential to target and erase traumatic memories.

Walcott, who served in a Balad-based transportation unit that regularly took mortar fire, now suffers from post-traumatic stress disorder. Since returning to the United States two years ago, he has been on antidepressants and in group therapy as he tries to put his life back together and heal from the psychological scars of war. "There are moments," he said, "when you just want be alone and don't want to deal with everyone telling you that you've changed."

There are many others like Walcott. The Army estimates that one in eight soldiers returning home from Iraq suffers from post-traumatic stress disorder. Symptoms of the disorder, once known as shell shock, include flashbacks, nightmares, feelings of detachment, irritability, trouble concentrating and sleeplessness.

Much about why painful memories come back to haunt soldiers and those who live through other traumatic experiences remains unknown. Scientists say that is because little is known about how the brain stores and recalls memories.

But in their early efforts to understand the way in which short-term memories become long-term memories, researchers have discovered that certain drugs can interrupt that process. Those same drugs, they believe, can also be applied not just in the immediate aftermath of a traumatic event — like a mortar attack, rape or car accident — but years later, when an individual is still haunted by memories of event.

The hope is that a post-traumatic stress disorder patient can work with a psychiatrist and focus a traumatic event, take one of these drugs and then slowly forget that event. With that hope, however, comes a series of ethical concerns. What makes up our personalities — the essence of who we are as individuals — if not the collected memories of our experiences?

"This is all very preliminary," said Dr. Roger Pitman, a Harvard Medical School psychiatrist. "We're just getting started. There is some promising preliminary data but no conclusions."

Much of the research Pitman is currently conducting on human subjects at Massachusetts General Hospital focuses on altering memories in the immediate aftermath of a specific type of trauma automobile accidents. Subjects who arrive in the hospital's emergency room are prescribed either the drug propranolol or a placebo.

Propranolol was originally developed to treat high blood pressure, but its effect on the hormone adrenaline has made it popular among actors dealing with severe stage fright, and scientists are now using it in their research on memory.

"There is a period of time after you first learn something before it's retained," Pitman explained. "This is called consolidation."

Some research has shown that stress hormones, particularly adrenaline, make that process faster and more intense.

"That's why you remember what you were doing the morning of Sept. 11, better than August 11," he said.

Some scientists believe that post-traumatic stress disorder is the result of too much adrenaline entering the brain at the moment the memory of a traumatic event is being consolidated, or stored, for the first time.

But "the real hot topic," Pitman said, is not consolidation but reconsolidation, the process by which an old memory is recalled and the same "window of opportunity" to alter it with drugs is opened for a second time.

By getting soldiers, or others who have lived through harrowing experiences, to remember their traumatic experiences through talking therapy, the theory goes, the chance to target and erase those memories presents itself.

Reconsolidation remains a "controversial" theory according to Pitman, but Joseph LeDoux, a psychologist at New York University's Center for Neural Science, said his recent experiments with rats adds to evidence that it's real.

LeDoux is not trying to create a drug to treat humans. For him, the specific drug isn't important. What is important is understanding the process by which memories are retained and altered.

"The idea is that memories are vulnerable. They can be improved or weakened. The main point is that we're trying to understand how this all works rather than come up with a drug."

But the idea of improving or weakening people's memories gives many medical ethicists pause.

The President's Council on Bioethics has condemned memory-altering research. The National Institutes of Health, however, has funded some experiments that use propranalol for post-traumatic stress disorder treatment, and Pitman said he has received a grant from the Army to begin conducting similar research with Iraq veterans.

"There are several major concerns" about creating these kinds of drugs, said Felicia Cohn, a medical ethicist at University of California at Irvine's School of Medicine. "Is the act of altering memories even an appropriate medical intervention?" she asked.

Another set of "issues is related to consequences. What are the effects of altering a particular person's memory but not changing the context the person is living in. We might erase a young girl's memory of a rape, but people around her will still know and inadvertently remind her," Cohn said.

"It becomes a genie in the bottle question. Once a drug is available for use, it gets used appropriately and inappropriately. People could start going to physicians to forget they love chocolate. … Is it just for post-traumatic stress disorder and rape victims? Where do we draw the line? Who gets to decide what is horrific enough?"



http://abcnews.go.com/Health/story?id=2964509&page=1

 

i just see technology for what it really is.....a double edged sword.