Andi
12-31-05, 08:15 AM
Therapies use drugs, mental exercises to change the way your brain recalls bad events
Sharon Kirkey
The Ottawa Citizen
Friday, December 30, 2005
"Nothing fixes a thing so intensely in the memory as the wish to forget it," French Renaissance scholar Michel de Montaigne wrote, and Joyce Boaz knows how true this is.
She knows what survivors of traumatic events -- domestic violence, childhood abuse, assault, rape, car crashes -- do to try to get "what's inside them out."
Prozac, Paxil or Zoloft, alone or combined with tranquillizers. Poetry, art, sculpture. Psychotherapy or "extinction learning" or "eye movement desensitization and reprocessing."
"Sometimes talk therapy is just not enough," says Ms. Boaz, who runs a support network from Camden, Maine, that matches isolated people living with traumatic memories.
"It's not like there's a magic pill. That's the problem. It's not like there's one drug, like maybe for polio."
That could soon change.
In experiments that go against once deep-rooted thinking about memory, Canadian scientists are working on a way to alter traumatic thoughts. McGill University researchers in Montreal are using a common blood pressure drug to make "fixed" bad memories unstable and as pliable as playdough.
The experiments build on a five-year-old discovery that the sheer act of recalling an emotionally charged memory returns the memory to a state where it can be tampered with or stopped from "reconsolidating."
So far, 20 men and women with post-traumatic stress disorder have been seated, fitted with headphones and made to listen to a vivid retelling in their own voices of the traumatic event.
Half were given two doses of the beta-blocker propranolol, the other half a placebo. Then palm sweat, heart rate and other changes were assessed to determine whether the physiological response to the traumatic story decreased among those who got the drug.
When humans take in new information -- whether it's a phone number, or seeing someone killed -- the memory is "labile" at first, or chemically unstable.
But at some point within the next six hours, a flood of proteins produced by the brain moves the memory from short-term to a long-term imprint.
But long-term memories aren't nearly as hardwired as once thought. Scientists now say that if a highly emotional memory is reactivated and those proteins blocked with a drug such as propranolol, it may be possible to stop the memory from being restabilized.
The goal is to, at the very least, dampen traumatic memories.
"The propranolol is actually turning down the gradient of the emotionality of the trauma, so it's targeting the emotional memory," says Karim Nader, an associate professor of psychology at McGill.
Principal investigator Alain Brunet is quick to stress that what he and his collaborators are not doing is erasing memory, something they've already achieved in rats.
"It's not that people will no longer remember the trauma, but the memory will be less painful," says Mr. Brunet, assistant professor in the department of psychiatry at McGill.
"They remember what they did, how things unfolded. I'll tell you this: People with (post-traumatic stress disorder), their life is so miserable, they tell us they are willing to try anything to feel better."
If the approach works with post-traumatic stress disorder, it might help drug addicts or people with acquired performance anxiety. It's possible it might help epilepsy or chronic pain, conditions that involve changes in the wiring in the brain.
"What we're dealing with is a robust memory process," Mr. Brunet explains. "We have yet to explore the boundaries of that phenomenon."
Propranolol isn't the only memory-muting agent being tested. Another is the antibiotic D-cycloserine, which is being used in conjunction with what's called extinction learning, according to Mr. Brunet.
"Let's say you were involved in a bad car accident with a red truck. The colour red will remind you of the car accident. That's fear conditioning.
"If I present the colour red over and over again, and nothing bad happens, at first it will remind you of your trauma. But eventually it will only very remotely remind you of your trauma. That's extinction learning."
Mr. Nader says the horror of post-traumatic stress disorder makes it almost unethical not to try. But the prospect of being able to swallow a pill to forget something you would rather not remember has some experts in the field more than a little skittish.
What about witnesses in criminal cases? What if the traumatic memory is only half wiped out, leaving a shadowy memory that's upsetting, but the person can't fully understand why? And what if the pill takes good memories with it, so you forget happy memories of childhood?
"I believe such drugs will make us worse as people," Nobel Prize-winning memory researcher Eric Kandel told New Scientist in a cover story this month on the science of memory manipulation. Mr. Kandel, of Columbia University, says there's a reason people who do bad things are haunted by their memories. "The nightmares make them a better person, because they realize the implication of their actions -- it feels bad to hurt other people."
Memories are formed because a kind of volume switch gets engaged when there's something emotional happening. That's why we remember things that have emotional meaning -- graduations, weddings, or the birth of a child -- better than we do completely neutral events.
With post-traumatic stress disorder, that gain-switch "just gets turned way up after trauma. So now what happens is that people are just overwhelmed by their emotional memories."
Nietzsche's philosophy that "that which does not kill us makes us stronger" doesn't hold up for traumatic events in life, says Dr. Edward Hickling of the Center for Stress and Anxiety Disorders at the University of Albany in New York. People who have experienced or witnessed a trauma can suffer such fear, helplessness and horror that they're crippled by nightmares, flashbacks, outbursts of anger and hyper-vigilance and arousal, and constantly on the lookout for danger.
Some try not to think about it, or avoid anyone who reminds them of the trauma. Dr. Hickling says they can become withdrawn and so emotionally and psychologically numb they no longer can feel love or other intense feelings the way they did before. Dr. Hickling, co-author of After the Crash, a book about the assessment and treatment of car accident survivors, says if those powerful reactions could be stopped, "the emotional reaction may never occur or stick."
He found that 76 per cent of people with post-traumatic stress improved with brief, 10-session cognitive behaviour therapy. They've now piloted an even shorter treatment, just two and a half sessions, that's showing promise, provided people are caught early.
"But a lot of people at that time really feel that they can do it on their own, and they prefer to see if things are going to just get sorted out. If there was a drug that helped, that would be great. It might be what most people are open to."
Anyone facing a life-threatening situation releases a rush of stress hormones produced by the adrenal gland that prime the body to "fight, flee or freeze." That hormonal rush also boosts the brain's ability to form and retain emotional memories.
Propranolol has been shown to reduce memories by blocking those adrenergic pathways.
In a recent study by psychiatrist Roger Pitman and colleagues at Harvard Medical School, 31 trauma victims who were seen in a hospital emergency room within hours of the event were randomly assigned to take propranolol or a placebo.
There were no fewer cases of post-traumatic stress disorder in the drug group, but they did have lower measures of stress when they were tested three months later.
Dr. Pitman is now working with the McGill scientists to see if propranolol can alter memories years after they have been laid down in the brain. The results could be published in six months.
For people with post-traumatic stress disorder, it could mean the difference between unrelenting mental suffering, and a normal life. The Montreal researchers say the intent is not to wipe out the memory, because many people with post-traumatic stress disorder self-identify with the trauma.
"Let's say they woke up one day and they can't remember the trauma," Mr. Nader says. Then who are they? "We want to stay away from that, even if we had something where we could do it."
Are the attempts to alter memory ethical? "For the PTSD patient, it's pretty obvious," Mr. Nader says.
"They have zero quality of life and they're suffering a stupendous amount. The manipulations that are being tried out there are using drugs that, in my mind, are relatively benign. The potential payoff, if they work, will be great.
"But I'll get e-mails from people, or get a phone call, saying, 'I want to get rid of the memories of my ex-husband.' Then what?
"Where is the grey zone going to be? And who is going to decide where that line is going to be?"
http://www.canada.com/ottawacitizen/news/story.html?id=5b95312a-80b4-487f-bb31-1bcf0dfc1a90&k=33697
Sharon Kirkey
The Ottawa Citizen
Friday, December 30, 2005
"Nothing fixes a thing so intensely in the memory as the wish to forget it," French Renaissance scholar Michel de Montaigne wrote, and Joyce Boaz knows how true this is.
She knows what survivors of traumatic events -- domestic violence, childhood abuse, assault, rape, car crashes -- do to try to get "what's inside them out."
Prozac, Paxil or Zoloft, alone or combined with tranquillizers. Poetry, art, sculpture. Psychotherapy or "extinction learning" or "eye movement desensitization and reprocessing."
"Sometimes talk therapy is just not enough," says Ms. Boaz, who runs a support network from Camden, Maine, that matches isolated people living with traumatic memories.
"It's not like there's a magic pill. That's the problem. It's not like there's one drug, like maybe for polio."
That could soon change.
In experiments that go against once deep-rooted thinking about memory, Canadian scientists are working on a way to alter traumatic thoughts. McGill University researchers in Montreal are using a common blood pressure drug to make "fixed" bad memories unstable and as pliable as playdough.
The experiments build on a five-year-old discovery that the sheer act of recalling an emotionally charged memory returns the memory to a state where it can be tampered with or stopped from "reconsolidating."
So far, 20 men and women with post-traumatic stress disorder have been seated, fitted with headphones and made to listen to a vivid retelling in their own voices of the traumatic event.
Half were given two doses of the beta-blocker propranolol, the other half a placebo. Then palm sweat, heart rate and other changes were assessed to determine whether the physiological response to the traumatic story decreased among those who got the drug.
When humans take in new information -- whether it's a phone number, or seeing someone killed -- the memory is "labile" at first, or chemically unstable.
But at some point within the next six hours, a flood of proteins produced by the brain moves the memory from short-term to a long-term imprint.
But long-term memories aren't nearly as hardwired as once thought. Scientists now say that if a highly emotional memory is reactivated and those proteins blocked with a drug such as propranolol, it may be possible to stop the memory from being restabilized.
The goal is to, at the very least, dampen traumatic memories.
"The propranolol is actually turning down the gradient of the emotionality of the trauma, so it's targeting the emotional memory," says Karim Nader, an associate professor of psychology at McGill.
Principal investigator Alain Brunet is quick to stress that what he and his collaborators are not doing is erasing memory, something they've already achieved in rats.
"It's not that people will no longer remember the trauma, but the memory will be less painful," says Mr. Brunet, assistant professor in the department of psychiatry at McGill.
"They remember what they did, how things unfolded. I'll tell you this: People with (post-traumatic stress disorder), their life is so miserable, they tell us they are willing to try anything to feel better."
If the approach works with post-traumatic stress disorder, it might help drug addicts or people with acquired performance anxiety. It's possible it might help epilepsy or chronic pain, conditions that involve changes in the wiring in the brain.
"What we're dealing with is a robust memory process," Mr. Brunet explains. "We have yet to explore the boundaries of that phenomenon."
Propranolol isn't the only memory-muting agent being tested. Another is the antibiotic D-cycloserine, which is being used in conjunction with what's called extinction learning, according to Mr. Brunet.
"Let's say you were involved in a bad car accident with a red truck. The colour red will remind you of the car accident. That's fear conditioning.
"If I present the colour red over and over again, and nothing bad happens, at first it will remind you of your trauma. But eventually it will only very remotely remind you of your trauma. That's extinction learning."
Mr. Nader says the horror of post-traumatic stress disorder makes it almost unethical not to try. But the prospect of being able to swallow a pill to forget something you would rather not remember has some experts in the field more than a little skittish.
What about witnesses in criminal cases? What if the traumatic memory is only half wiped out, leaving a shadowy memory that's upsetting, but the person can't fully understand why? And what if the pill takes good memories with it, so you forget happy memories of childhood?
"I believe such drugs will make us worse as people," Nobel Prize-winning memory researcher Eric Kandel told New Scientist in a cover story this month on the science of memory manipulation. Mr. Kandel, of Columbia University, says there's a reason people who do bad things are haunted by their memories. "The nightmares make them a better person, because they realize the implication of their actions -- it feels bad to hurt other people."
Memories are formed because a kind of volume switch gets engaged when there's something emotional happening. That's why we remember things that have emotional meaning -- graduations, weddings, or the birth of a child -- better than we do completely neutral events.
With post-traumatic stress disorder, that gain-switch "just gets turned way up after trauma. So now what happens is that people are just overwhelmed by their emotional memories."
Nietzsche's philosophy that "that which does not kill us makes us stronger" doesn't hold up for traumatic events in life, says Dr. Edward Hickling of the Center for Stress and Anxiety Disorders at the University of Albany in New York. People who have experienced or witnessed a trauma can suffer such fear, helplessness and horror that they're crippled by nightmares, flashbacks, outbursts of anger and hyper-vigilance and arousal, and constantly on the lookout for danger.
Some try not to think about it, or avoid anyone who reminds them of the trauma. Dr. Hickling says they can become withdrawn and so emotionally and psychologically numb they no longer can feel love or other intense feelings the way they did before. Dr. Hickling, co-author of After the Crash, a book about the assessment and treatment of car accident survivors, says if those powerful reactions could be stopped, "the emotional reaction may never occur or stick."
He found that 76 per cent of people with post-traumatic stress improved with brief, 10-session cognitive behaviour therapy. They've now piloted an even shorter treatment, just two and a half sessions, that's showing promise, provided people are caught early.
"But a lot of people at that time really feel that they can do it on their own, and they prefer to see if things are going to just get sorted out. If there was a drug that helped, that would be great. It might be what most people are open to."
Anyone facing a life-threatening situation releases a rush of stress hormones produced by the adrenal gland that prime the body to "fight, flee or freeze." That hormonal rush also boosts the brain's ability to form and retain emotional memories.
Propranolol has been shown to reduce memories by blocking those adrenergic pathways.
In a recent study by psychiatrist Roger Pitman and colleagues at Harvard Medical School, 31 trauma victims who were seen in a hospital emergency room within hours of the event were randomly assigned to take propranolol or a placebo.
There were no fewer cases of post-traumatic stress disorder in the drug group, but they did have lower measures of stress when they were tested three months later.
Dr. Pitman is now working with the McGill scientists to see if propranolol can alter memories years after they have been laid down in the brain. The results could be published in six months.
For people with post-traumatic stress disorder, it could mean the difference between unrelenting mental suffering, and a normal life. The Montreal researchers say the intent is not to wipe out the memory, because many people with post-traumatic stress disorder self-identify with the trauma.
"Let's say they woke up one day and they can't remember the trauma," Mr. Nader says. Then who are they? "We want to stay away from that, even if we had something where we could do it."
Are the attempts to alter memory ethical? "For the PTSD patient, it's pretty obvious," Mr. Nader says.
"They have zero quality of life and they're suffering a stupendous amount. The manipulations that are being tried out there are using drugs that, in my mind, are relatively benign. The potential payoff, if they work, will be great.
"But I'll get e-mails from people, or get a phone call, saying, 'I want to get rid of the memories of my ex-husband.' Then what?
"Where is the grey zone going to be? And who is going to decide where that line is going to be?"
http://www.canada.com/ottawacitizen/news/story.html?id=5b95312a-80b4-487f-bb31-1bcf0dfc1a90&k=33697