Post by Mech on Feb 12, 2004 16:20:13 GMT -5
Blanks for the memories
Someday you may be able to take a pill to forget painful recollections
By Scott LaFee
STAFF WRITER
February 11, 2004
There's a scene in Shakespeare's "Macbeth" where the protagonist implores a doctor to treat Lady Macbeth, who is wracked by memories of past bad acts.
"Canst thou not minister to a mind diseas'd,
Pluck from the memory a rooted sorrow,
Raze out the written troubles of the brain,
And with some sweet oblivious antidote
Cleanse the stuff'd bosom of that perilous stuff
Which weighs upon the heart?"
The doctor, of course, can offer no real salvation. Lady Macbeth is condemned to live with her bad memories. Recalling our past is a part of the human condition. But what if that reality changed? What if people – 400 years after Shakespeare asked – could take a pill to purposefully dim – perhaps erase – our most painful and unwanted memories?
The notion has long been a favorite of fiction writers, from Shakespeare to fantasists like the late Philip K. Dick, but serious people – scientists and scholars – now believe it might be possible.
"The burgeoning field of neuroscience is providing new, more specific, and safer agents to help us combat all sorts of psychic distress," wrote the authors of "Beyond Therapy," a recently released report by the President's Council on Bioethics.
"Soon, doctors may have just the 'sweet oblivious antidote' that Macbeth so desired: drugs that numb the emotional sting typically associated with our intensely bad memories."
The authors do not think this is necessarily a good thing.
Think it with feelings
Memory isn't a single entity. There are different kinds and types.
Short-term memory lasts just a few seconds. It's the ability to recall a phone number long enough to dial it. Capacity is limited. It's no coincidence that phone numbers are just seven numbers long. That's the working limit for most people's short-term memory.
Long-term memories come in two broad categories. Explicit memories are general knowledge, facts of life, conscious recollections, the sort of stuff most people think of as memory.
Implicit memories are perceptual abilities, motor skills, conditioned or instinctive responses that operate outside of consciousness, such as instantly recognizing an object or knowing how to ride a bike.
Researchers focus on long-term memory because it is the primary driver of behavior. Much about how long-term memories are formed or function is fuzzy or unknown, but some fundamentals are well-understood.
To wit: Strong emotions make strong memories.
Most daily events are quickly forgotten. They are memories writ in pencil, never made permanent. But some events provoke an emotional response. In these moments of joy or sadness, terror or surprise, the body is flooded with stress hormones released by the adrenal glands, which are located above the kidneys. This is part of the ancient "fight or flight" response. Hormones like adrenaline wash over the amygdala – an almond-shaped portion of the brain that processes emotion, most notably fear. Adrenaline tells the amygdala that what's happening at that moment is worth remembering, that this is a memory to be writ in neurological ink.
Here's where many neuroscientists think there's an opportunity to act, to perhaps dilute a potentially traumatic memory before it dries hard and fast.
"We've learned that if you can prevent the system from working, give a drug that blocks the action of stress hormones (upon the amygdala and brain), then you may be able to prevent the influence of making stronger memories," said James L. McGaugh, director of UC Irvine's Center for the Neurobiology of Learning and Memory and author of "Memory & Emotion: The Making of Lasting Memories."
Memory-altering drug research is currently focused on propranolol, one of several so-called beta blockers widely used to reduce blood pressure, treat abnormal heart rhythms and prevent migraines. The brand name for propranolol is Inderal. Other beta blocker brand names are Inderide, Innopran XL, Betachron E-R, Kerlone, Lopressor, Tenormin, Toprol XL, Visken and Zebeta.
Beta blockers work by "blocking" the stimulative influence of stress hormones – specifically adrenaline – upon the body, relaxing blood vessels and slowing nerve impulses inside the heart.
Experiments indicate propranolol also blocks the effect of adrenaline upon areas of the brain involved in memory formation, including the amygdala. It seems to disconnect emotion from memory.
In a study conducted by Larry Cahill, a neurobiologist at UC Irvine, McGaugh and others in the late 1990s, test subjects were told an emotionally neutral, comparatively boring story illustrated by 12 slides. A second group of subjects was then shown the same 12 slides. The related story, however, was much more emotional, involving a severely injured boy.
When later asked what they remembered seeing in the pictures, subjects in the second group recalled much greater detail about the story than the first group did about theirs.
Cahill and McGaugh then presented the second, emotionally upsetting story with slides to a third group of volunteers who were given a standard dose of propranolol or endurol (another beta blocker). Their memories, when tested three weeks later, were "just like that of subjects who had received the boring story," said McGaugh.
Subjects remembered the story, but without any emotional depth.
Such findings suggest an obvious potential therapeutic benefit: If people who have just experienced a traumatic event could be given a memory-dampening drug like propranolol, they might avoid suffering later psychic damage, such as post-traumatic stress disorder or PTSD.
Roughly 5 million Americans between the ages of 18 and 54 suffer from PTSD at any given time. Almost 8 percent of Americans will experience PTSD at some point in their lives, women twice as likely as men. Clearly, McGaugh and others said, there are times when blocking the formation of traumatic memories would be beneficial.
"Let me give you an example from the 1978 PSA (plane) crash in San Diego where they made the horrible mistake of sending out desk people and baggage handlers to clean up body parts after the crash. Later, there was a follow-up report that said a very high percentage of those people were never able to work again. They had been permanently disabled because of the trauma.
"Now, that's PTSD to the nth degree, that would be a case in which something like (a memory-blunting drug) would be of value."
Two subsequent studies reinforce the potential efficacy of using beta blockers to blunt memory. In a 2002 pilot study, Roger Pitman, a professor of psychiatry at Harvard University, recruited 31 people from the emergency room of Massachusetts General Hospital who had just been involved in a traumatic event, typically an automobile accident.
Someday you may be able to take a pill to forget painful recollections
By Scott LaFee
STAFF WRITER
February 11, 2004
There's a scene in Shakespeare's "Macbeth" where the protagonist implores a doctor to treat Lady Macbeth, who is wracked by memories of past bad acts.
"Canst thou not minister to a mind diseas'd,
Pluck from the memory a rooted sorrow,
Raze out the written troubles of the brain,
And with some sweet oblivious antidote
Cleanse the stuff'd bosom of that perilous stuff
Which weighs upon the heart?"
The doctor, of course, can offer no real salvation. Lady Macbeth is condemned to live with her bad memories. Recalling our past is a part of the human condition. But what if that reality changed? What if people – 400 years after Shakespeare asked – could take a pill to purposefully dim – perhaps erase – our most painful and unwanted memories?
The notion has long been a favorite of fiction writers, from Shakespeare to fantasists like the late Philip K. Dick, but serious people – scientists and scholars – now believe it might be possible.
"The burgeoning field of neuroscience is providing new, more specific, and safer agents to help us combat all sorts of psychic distress," wrote the authors of "Beyond Therapy," a recently released report by the President's Council on Bioethics.
"Soon, doctors may have just the 'sweet oblivious antidote' that Macbeth so desired: drugs that numb the emotional sting typically associated with our intensely bad memories."
The authors do not think this is necessarily a good thing.
Think it with feelings
Memory isn't a single entity. There are different kinds and types.
Short-term memory lasts just a few seconds. It's the ability to recall a phone number long enough to dial it. Capacity is limited. It's no coincidence that phone numbers are just seven numbers long. That's the working limit for most people's short-term memory.
Long-term memories come in two broad categories. Explicit memories are general knowledge, facts of life, conscious recollections, the sort of stuff most people think of as memory.
Implicit memories are perceptual abilities, motor skills, conditioned or instinctive responses that operate outside of consciousness, such as instantly recognizing an object or knowing how to ride a bike.
Researchers focus on long-term memory because it is the primary driver of behavior. Much about how long-term memories are formed or function is fuzzy or unknown, but some fundamentals are well-understood.
To wit: Strong emotions make strong memories.
Most daily events are quickly forgotten. They are memories writ in pencil, never made permanent. But some events provoke an emotional response. In these moments of joy or sadness, terror or surprise, the body is flooded with stress hormones released by the adrenal glands, which are located above the kidneys. This is part of the ancient "fight or flight" response. Hormones like adrenaline wash over the amygdala – an almond-shaped portion of the brain that processes emotion, most notably fear. Adrenaline tells the amygdala that what's happening at that moment is worth remembering, that this is a memory to be writ in neurological ink.
Here's where many neuroscientists think there's an opportunity to act, to perhaps dilute a potentially traumatic memory before it dries hard and fast.
"We've learned that if you can prevent the system from working, give a drug that blocks the action of stress hormones (upon the amygdala and brain), then you may be able to prevent the influence of making stronger memories," said James L. McGaugh, director of UC Irvine's Center for the Neurobiology of Learning and Memory and author of "Memory & Emotion: The Making of Lasting Memories."
Memory-altering drug research is currently focused on propranolol, one of several so-called beta blockers widely used to reduce blood pressure, treat abnormal heart rhythms and prevent migraines. The brand name for propranolol is Inderal. Other beta blocker brand names are Inderide, Innopran XL, Betachron E-R, Kerlone, Lopressor, Tenormin, Toprol XL, Visken and Zebeta.
Beta blockers work by "blocking" the stimulative influence of stress hormones – specifically adrenaline – upon the body, relaxing blood vessels and slowing nerve impulses inside the heart.
Experiments indicate propranolol also blocks the effect of adrenaline upon areas of the brain involved in memory formation, including the amygdala. It seems to disconnect emotion from memory.
In a study conducted by Larry Cahill, a neurobiologist at UC Irvine, McGaugh and others in the late 1990s, test subjects were told an emotionally neutral, comparatively boring story illustrated by 12 slides. A second group of subjects was then shown the same 12 slides. The related story, however, was much more emotional, involving a severely injured boy.
When later asked what they remembered seeing in the pictures, subjects in the second group recalled much greater detail about the story than the first group did about theirs.
Cahill and McGaugh then presented the second, emotionally upsetting story with slides to a third group of volunteers who were given a standard dose of propranolol or endurol (another beta blocker). Their memories, when tested three weeks later, were "just like that of subjects who had received the boring story," said McGaugh.
Subjects remembered the story, but without any emotional depth.
Such findings suggest an obvious potential therapeutic benefit: If people who have just experienced a traumatic event could be given a memory-dampening drug like propranolol, they might avoid suffering later psychic damage, such as post-traumatic stress disorder or PTSD.
Roughly 5 million Americans between the ages of 18 and 54 suffer from PTSD at any given time. Almost 8 percent of Americans will experience PTSD at some point in their lives, women twice as likely as men. Clearly, McGaugh and others said, there are times when blocking the formation of traumatic memories would be beneficial.
"Let me give you an example from the 1978 PSA (plane) crash in San Diego where they made the horrible mistake of sending out desk people and baggage handlers to clean up body parts after the crash. Later, there was a follow-up report that said a very high percentage of those people were never able to work again. They had been permanently disabled because of the trauma.
"Now, that's PTSD to the nth degree, that would be a case in which something like (a memory-blunting drug) would be of value."
Two subsequent studies reinforce the potential efficacy of using beta blockers to blunt memory. In a 2002 pilot study, Roger Pitman, a professor of psychiatry at Harvard University, recruited 31 people from the emergency room of Massachusetts General Hospital who had just been involved in a traumatic event, typically an automobile accident.