A soldier shocked by the horrors of war can return home to find he or she can't stop the memories from flooding back in flashbacks that make it impossible to sleep and function.
But what if there were a way to dull those memories?
Not delete the memory completely, like in the film "Eternal Sunshine of the Spotless Mind." But somehow tone down the intense emotions that sufferers of post-traumatic stress disorder typically feel whenever they relive their trauma.
That's the promise of research being carried out by Canadian neurosciences phenom Dr. Karim Nader, at Montreal's McGill University.
Nader, once named by Forbes as one of the "Ten People Who Could Change The World," has helped pioneer research on medication that can help strip traumatic memories of their power. It fact, it was his research along with colleagues at Harvard that inspired the "Spotless Mind" script.
In the film, Jim Carrey's character completely erases all memories of his ex-girlfriend, played by Kate Winslet, keeping the rest of his memories intact. Such a possibilty is still just the stuff of fiction, Nader says, and probably not even ideal anyway.
"Let's say we could do what they did in ‘Eternal Sunshine' and we could get rid of the entire memory. When the person ‘woke up' after struggling for years with PTSD, they'd ask ‘Why am I an alcoholic? Why am I doing drugs? Why have I lost my family?'"
Nader said in an interview. "We realized that if we got rid of the entire memory, that's not optimal."
That's why Nader is researching ways to dull the pain of the trauma, to turn a traumatic memory that keeps them up at night into just an ordinary bad memory.
The key lies in blocking the emotional response generated by the memory.
"If you have an emotional stimulus, you're going to remember that event better. That's why maybe you can remember your 16th birthday better than you can remember what you did three Tuesdays ago," Nader explains.
Nader realized something special about memory 10 years ago. It had long been assumed that once a memory is formed, it's filed away in our brain and can't be changed. But by using lab rats as test subjects, Nader found that when one recalls a memory, pulling it out of the brain's virtual file cabinet, that memory is in a vulnerable state for a little while, and the memory can be altered before being filed away in a new way. Nader found that the very act of remembering changed the memories. It's a process he called "memory reconsolidation."
Nader theorized that the reconsolidation phase might be an ideal time to alter the memory and block the emotional response associated with that memory, through a process dubbed "reconsolidation blockade."
After Nader's research was published in 2000, he was approached by prominent psychiatrist Dr. Roger Pitman of the Harvard Medical School. Pitman had been researching how to help trauma victims using medications, focusing on drugs that could target the hormones that are released during a memorable event.
Nader explains that all emotional events, good and bad, cause hormones, such as adrenalin, to be released.
"These hormones can actually boost how intensely memories are stored," Nader explains. "So if you can block these hormones, you block the boosting, but you're keeping the information intact."
The medication they looked at is called propranolol. It's a commonly prescribed beta blocker developed over 40 years ago. The drug is usually given to patients with angina or high blood pressure because of its ability to block adrenalin. In fact, it's so good at blocking adrenalin, it's banned from the Olympics, because it helps control stage fright and trembling.
Pitman showed that propranolol given within a few hours after a trauma decreased the possibility the patients would later develop PTSD. When Pitman saw Nader's work on reconsolidation, he contacted him and said "We should try this on patients with PTSD."
They recruited a small group of patients who had suffered from PTSD for more than 10 years. On one day, they asked the patients to describe the trauma. They then gave half the group either doses of propranolol or a placebo. A week later, they asked the patients to recall the memory.
They found that those in the propranolol group showed a more muted physiological response to the memory, as measured by heart rate monitors and skin tests.
Nader explains that after the propranolol treatment, the actual memory of the event remains intact, but the medication has helped prevent the emotional and physical response.
"It's like overdriving the brain, so that the memory becomes just like an old, bad memory that they can cope with. Without that, the memory is just far too strong for their normal ‘brakes' to control," Nader explains.
"So we found that we can bring the strength of the memory down to non-PTSD levels -- which really, is just crazy for someone who has had PTSD for 30 years."
Interestingly, while the physical responses in the treated patients were changed and while the patients said they felt better, the patients didn't report feeling significantly better than the placebo group.
Nader isn't sure why that is. That's why he and his team are working on further research.
"Now we're trying to see in a larger collaboration, whether if we give maybe six of these treatments once a week, will we get a bigger effect on the self-reported side?" he says.
A McGill team, along with and others in the field, are also experimenting with propranolol in cocaine addiction. Cocaine is notoriously difficult to kick, but the research is finding that cocaine-addicted lab rats can recover with the use of propranolol to block the retrieval of memories associated with being high.
Nader concedes there is a possibility that the placebo effect could be playing a role in his research, and that PTSD patients might report they feel better because they really want to feel better. But if that's the case, it's okay with Nader.
"Even if it's just 80 per cent placebo and only about 20 per cent reconsolidation blockade, from a clinical perspective, they would be better," he says. "So a big part of me says: if they get better, who cares if its reconsolidation blockade?"
"If it's placebo effect or whatever, at least it works."
