Researchers work on memory-erasing drugs
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Researchers work on memory-erasing drugs
Thursday, November 19, 2009
AP– (11/19/09) — Taking a pill could wipe away all of your painful memories.
HealthFirst reporter Leslie Toldo tells us about research that sounds like a sci-fi movie plot.
There is proof it can be done. The real question is, would you really want to do it?
The answer isn’t as easy as you might think.
These pictures, medals and pins are reminders of a time war veteran Allen Megginson would rather forget. “I think that no matter how much time passes, it’s really not going to ease the pain any.”
Megginson fought in the Iraq War. What he saw and experienced are now memories that haunt him every day. “Sometimes the wounds that hurt the most are the ones you can’t see.”
What if Megginson could forget those horrible memories? After decades of research, neuroscientist Dr. Andre Fenton and colleagues have discovered what they call the memory molecule. “This is the first physical identification of a molecule that is definitively important for storing memory,” Fenton claimed.
In a lab experiment, Fenton manipulated that molecule in the brains of rats. The animals were put on a turntable. One area delivered a mild shock to the foot. But when researchers injected a drug called zip into their brains, watch how the rats go straight to the spot that shocked them. They forgot what they had learned.
“We could always see that the animals could no longer remember to avoid that particular place.”
While this research is in animals, investigators from Harvard are studying whether another drug called propranolol can weaken the emotional response to memories in humans. But medical ethicist Felicia Cohn, Ph.D. says there are real concerns about editing memory
“You start changing somebody’s memories, you can raise the question of whether or not you’re changing their identity in some fundamental way.”
Even Megginson says he wouldn’t want to take a drug to help him forget. “I may have these bad memories, but they make me the person I am today.”
Researchers are also studying the effects of certain painkillers, anti-nausea drugs and the abortion drug RU486 for memory blocking in animals.
BACKGROUND: According to the National Institute of Mental Health, posttraumatic stress disorder, or PTSD, is an anxiety disorder that some people get after seeing or living through a dangerous event. The intense fear triggers split-second changes in the body to defend against danger. In PTSD, this reaction is changed or damaged. People with PTSD may feel stressed or frightened even when they are no longer in danger. Anyone can develop PTSD at any age. War veterans and survivors of physical and sexual abuse are commonly diagnosed with the disorder. Not everyone with PTSD has been through a dangerous event. Some people develop PTSD after a friend or family member experiences danger or is harmed. The sudden, unexpected death of a loved one can also cause PTSD.
It sounds like science fiction, but some researchers are studying whether certain drugs can erase or dim bad memories. The possibility of memory blocking has some ethicists concerned. Felicia Cohn, Ph.D., director of medical ethics at the University of California, Irvine, says erasing memories may be erasing someone’s identity. “If you start changing somebody’s memories, you can raise the question of whether or not you’re changing their identity in some fundamental way,” Cohn told Ivanhoe. She says even bad memories teach us important lessons. “Whether it means we become more protective with our children or we lock our doors more often at night, or you know, even subtle behavior changes can really make a big difference in the way we live,” Cohn said.
ZIP: Researchers in Brooklyn are studying the drug known as “ZIP” in animals. They conducted an experiment where they put the animals on a turntable. One region of the table delivered a mild foot shock, so the animals learned to stay away from that area. After the researchers injected ZIP into their brains, the rats went straight to the spot that shocked them, meaning they forgot what they had learned.
PROPRANOLOL: Researchers from Harvard and elsewhere have been studying whether the drug propranolol can dim the emotional response to memories in people with PTSD. In one preliminary trial, investigators found the pill “significantly reduced physiological responses” in the patients. Researchers say the drug works by influencing the reconsolidation of memories, which is the shaping of already-formed — or consolidated — memories. In another recent study involving the drug, researchers trained 60 people to associate a picture of a spider with an electric shock. After the conditioning, students who were given propranolol before seeing the picture were not startled, while the other students were.