Researchers discover how to erase memory

(PhysOrg.com) -- Researchers working with mice have discovered that by removing a protein from the region of the brain responsible for recalling fear, they can permanently delete traumatic memories. Their report on a molecular means of erasing fear memories in rodents appears this week in Science Express.

“When a traumatic event occurs, it creates a fearful memory that can last a lifetime and have a debilitating effect on a person’s life,” says Richard L. Huganir, Ph.D., professor and director of neuroscience at the Johns Hopkins University School of Medicine and a Howard Hughes Medical Institute investigator. “Our finding describing these molecular and cellular mechanisms involved in that process raises the possibility of manipulating those mechanisms with drugs to enhance behavioral therapy for such conditions as post-traumatic stress disorder.”

Behavioral therapy built around “extinction training” in animal models has proven helpful in easing the depth of the emotional response to , but not in completely removing the memory itself, making relapse common.


Huganir and postdoctoral fellow Roger Clem focused on the nerve circuits in the amygdala, the part of the known to underly so-called fear conditioning in people and animals. Using sound to cue fear in mice, they observed that certain cells in the amygdala conducted more current after the mouse was exposed to a loud, sudden tone.

In hopes of understanding the molecular underpinnings of formation, the team further examined the proteins in the nerve cells of the amygdala before and after exposure to the loud tone. They found temporary increases in the amount of particular proteins — the calcium-permeable AMPARs — within a few hours of fear conditioning that peaked at 24 hours and disappeared 48 hours later.

Because these particular proteins are uniquely unstable and can be removed from nerve cells, the scientists proposed that they might permanently remove fear by combining behavior therapy and removal and provide a window of opportunity for treatment. “The idea was to remove these proteins and weaken the connections in the brain created by the trauma, thereby erasing the memory itself,” says Huganir.

In further experiments, they found that removal of these proteins depends on the chemical modification of the GluA1 protein. Mice lacking this chemical modification of GluA1 recovered fear memories induced by loud tones, whereas littermates that still had normal GluA1 protein did not recover the same memories. Huganir suggests that drugs designed to control and enhance the removal of calcium-permeable AMPARs may be used to improve memory erasure.

“This may sound like science fiction, the ability to selectively erase memories,” says Huganir. “But this may one day be applicable for the treatment of debilitating fearful memories in people, such as post-traumatic stress syndrome associated with war, rape or other traumatic events.”

This study was funded by the National Institutes of Health and the Howard Hughes Medical Institute.

More information: Publication: Science, "Calcium-Permeable AMPA Receptor Dynamics Mediate Fear Memory Erasure," by R.L. Clem; R.L. Huganir at Howard Hughes Medical Institute in Baltimore, MD; R.L. Clem; R.L. Huganir at Johns Hopkins University School of Medicine in Baltimore, MD. www.sciencemag.org/sciencexpress/recent.dtl
Citation: Researchers discover how to erase memory (2010, November 1) retrieved 25 May 2019 from https://medicalxpress.com/news/2010-11-erase-memory.html
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Nov 01, 2010
we are very close to removing any cost to having participated in a war indeed. soldiers can now be sent again and again to far away land to conduct a war and take few weeks to suppress the associated memories before being shipped again to a different area this time.
But progress is progress and this will certainly benefit to many.

Nov 01, 2010
Not sure about that, wouldn't you also be stripping them of the experience gained from that war, which could lead to repeated mistakes and more deaths?
I think a better use is for people who have had really bad crimes commited against them.

Nov 01, 2010
For more scientific studies on the effects of erasing ones memories, see:

http://en.wikiped...k_(film)

Nov 01, 2010
One of my children had a traumatic experience in a religious cult. The memories create great anguish in her, which generates the same in her parents. This process could be of great help to folks having experienced any life-altering negative experience.

Nov 01, 2010
I sure as hell have a few I'd sign up to have taken out.

Question is then, am I the same person afterward? Sometimes painful experiences are what make us stronger and dare I say, BETTER people. Sometimes.

OTOH we're never the same person we were even just yesterday...

Nov 01, 2010
This reasearch is as flat out immoral as the scientists who developed the atomic bomb.


Then using your nonsensical and misguided logic, that means you love Nazi's and genocide

Nov 01, 2010
Interesting. It wouldn't be the correct thing to do, but most interesting research.

Nov 01, 2010
Removing the actual memory would not change the impact of the memory, extinction therapy would also be needed. In combination, they would ease the trauma and prevent it from re-occurring. This isn't a "Men in Black" eraser ray.

Nov 02, 2010
I wonder if the same method could be applied to soften up hardwired addictions in the pleasure centres, or in contrast, purposely deliver some proteins to learning centres while learning difficult skills, or to reinforce good behaviour (wich is entirely subjective as for instant suicide bombers are convinced they are doing it for the Good cause)

Nov 02, 2010
The mind works the way it does for a reason.

What reason? The mind is an evolved survival trait. Understanding it is key to continued advancement of humanity.

We have no right to mess with that.

Who gave you the right to decide this? I think your statement is one made from fear, which is understandable, but still biased.

This research is as flat out immoral as the scientists who developed the atomic bomb.

Developing technologies, including weapons, is neither right nor wrong. How those technologies (weapons) are used can be regarded as moral or immoral. I would blame the politicians if anyone.

Nov 02, 2010
a simple mixture of brandy,whiskey and beer should do the job of erasing memories just fine

Nov 06, 2010
@jalmy: I see where you're coming from, but tell me this: a person suffers a traumatic event. How is it that's gonna "teach" him/her? You're walking down the street, then something horrible happens; is that your fault? No, you were just another victim of this world's arbitrary game of chance.

How about people who lost in the DNA roulette, and were born blind or disabled? If we can treat them, we will; if we can ease the pain of the victims of traumatic events, we will. It's easy to sit back and watch others get destroyed while you're there, cozily typing away stuff on your computer, like I am now. Except I'm not saying "screw them". Grow some empathy please.

Nov 07, 2010
jalmy, I definitely get where you are coming from and I agree that this is scary science with some deep moral and practical implications. However, I don't think it should be discounted entirely. As with most things in life, this could be used for good or bad.

You can use a car to carry food to a starving village or you can use it to run someone over. Such duality of use is inevitable.

But I think we must weight things carefully before passing judgement on something like this. Yes, it could be used badly. But what about people with severe PTSD who can't even live a normal life anymore? Sure, many times bad experiences can make you a stronger person. But there are plenty of people out there that experience things so traumatic that it greatly affects their ability to live a happy life.

Nov 07, 2010
Who are you or I to say that they have to live with that memory forever? If they want to keep it that's fine, but what if they decide they want a little peace? Personally, I'm not going to lecture a child of a warzone on why they need to remember their parents being killed or tell a person that their memory of being assaulted is a good thing.

I'm not sure what I think of this kind of thing to be honest. But I think we all need to remain a bit humble when judging something that has a possibility of helping people.

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