How Our Brains Make Memories
Surprising new research about the act of remembering may help people with post-traumatic stress disorder
- By Greg Miller
- Photographs by Gilles Mingasson
- Smithsonian magazine, May 2010, Subscribe
Memories are stored in a region of the brain called the hippocampus, shown in red in this computer illustration. Photo Researchers, Inc.
Sitting at a sidewalk café in Montreal on a sunny morning, Karim Nader recalls the day eight years earlier when two planes slammed into the twin towers of the World Trade Center. He lights a cigarette and waves his hands in the air to sketch the scene.
At the time of the attack, Nader was a postdoctoral researcher at New York University. He flipped the radio on while getting ready to go to work and heard the banter of the morning disc jockeys turn panicky as they related the events unfolding in Lower Manhattan. Nader ran to the roof of his apartment building, where he had a view of the towers less than two miles away. He stood there, stunned, as they burned and fell, thinking to himself, “No way, man. This is the wrong movie.”
In the following days, Nader recalls, he passed through subway stations where walls were covered with notes and photographs left by people searching desperately for missing loved ones. “It was like walking upstream in a river of sorrow,” he says.
Like millions of people, Nader has vivid and emotional memories of the September 11, 2001, attacks and their aftermath. But as an expert on memory, and, in particular, on the malleability of memory, he knows better than to fully trust his recollections.
Most people have so-called flashbulb memories of where they were and what they were doing when something momentous happened: the assassination of President John F. Kennedy, say, or the explosion of the space shuttle Challenger. (Unfortunately, staggeringly terrible news seems to come out of the blue more often than staggeringly good news.) But as clear and detailed as these memories feel, psychologists find they are surprisingly inaccurate.
Nader, now a neuroscientist at McGill University in Montreal, says his memory of the World Trade Center attack has played a few tricks on him. He recalled seeing television footage on September 11 of the first plane hitting the north tower of the World Trade Center. But he was surprised to learn that such footage aired for the first time the following day. Apparently he wasn’t alone: a 2003 study of 569 college students found that 73 percent shared this misperception.
Nader believes he may have an explanation for such quirks of memory. His ideas are unconventional within neuroscience, and they have caused researchers to reconsider some of their most basic assumptions about how memory works. In short, Nader believes that the very act of remembering can change our memories.
Much of his research is on rats, but he says the same basic principles apply to human memory as well. In fact, he says, it may be impossible for humans or any other animal to bring a memory to mind without altering it in some way. Nader thinks it’s likely that some types of memory, such as a flashbulb memory, are more susceptible to change than others. Memories surrounding a major event like September 11 might be especially susceptible, he says, because we tend to replay them over and over in our minds and in conversation with others—with each repetition having the potential to alter them.
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Related topics: Brain Health Thought Innovation
Additional Sources
“Effect of post-retrieval propranolol on psychophysiologic responding during subsequent script-driven traumatic imagery in post-traumatic stress disorder,” Alain Brunet et al., Journal of Psychiatric Research, May 2008
“Disruption of reconsolidation but not consolidation of auditory fear conditioning by noradrenergic blockade in the amygdala,” J. Dębiec and J. E. LeDoux, Neuroscience, October 2, 2004
“Event Memory and Autobiographical Memory for the Events of September 11, 2001,” Kathy Pezdek, Applied Cognitive Psychology, January 8, 2004
“Fear memories require protein synthesis in the amygdala for reconsolidation after retrieval,” Karim Nader et al., Nature, August 17, 2000
“Reconsolidation of memory after its reactivation,” Jean Przybyslawski and Susan J. Sara, Behavioural Brain Research, March 1997
“Semantic Integration of Verbal Information into a Visual Memory,” Elizabeth F. Loftus et al., Journal of Experimental Psychology, January 1978
“Retrograde Amnesia Produced by Electroconvulsive Shock after Reactivation of a Consolidated Memory Trace,” James R. Misanin et al., Science, May 3, 1968
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Comments (30)
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Some of us have a near "photographic" memory. I often end up in minor arguments with my wife as her memory modifies itself over time - usually in a direction which makes HER the "perfect" one and whatever happened "my fault."
She's even gone so far as to accuse me of falsifying papers or even modifying a videotape to support "my version of events."
She literally has trouble accurately remembering what she had for breakfast while I can "see" minute details of things years later.
On the other hand, she REALLY scrambles me up when she "helps me" by "putting my stuff away (read: where SHE wants it) for me.
If she'd left it wherever I put it, I can find it by "zooming out" on my mental image of whatever "it" is.
When she moves it, it's usually LOST as she'll usually have no idea where she decided it "belongs" when asked to retrieve it later.
I'm convinced that such matters are at times - with folks possessing less self-control - a recurring cause of serious marital conflict...
Posted by Dedicated_Dad on December 18,2011 | 04:53 PM
Speaking Of Memory And Of Culture-Genetics
A. From “Speaking of Memory, Eric Kandel”
http://the-scientist.com/2011/10/01/interview-speaking-of-memory/
Are there unanswerable questions in neuroscience; ones that should be left to philosophers and poets?
Who’s to know what will emerge 50 to 100 years from now. But for the foreseeable future I think it’s our lack of ingenuity that is limiting, not the intrinsic difficulties; the problems are difficult—but not insurmountable. Even love?
I think there’ll always be magic to life, even though science explains a great deal.
B. BioCulture
June 16, 2006
http://universe-life.com/2006/06/16/bioculture/
To paraphrase a statement by Eugene Thacker in the opening pages of Biomedia (ISBN 0-8166-4353-9):
I posit that as every organism's cultural element is an artifact which involves biological intra-/inter-cell expression and/or process, biological and cultural domains are not ontologically distinct, but instead culture inheres in biology. Dov Henis
C. On “our lack of ingenuity” and “science explains”
Bigger Human Brain, Horses And Wagon
http://universe-life.com/2011/10/19/bigger-human-brain-horse-and-wagon/
On Culture And Genetics, Horses And Wagon
http://universe-life.com/2011/08/26/on-culture-and-genetics-horses-and-wagon/
If you saw it once, you saw it a million times: it’s the horses pulling, not the wagon pushing !
Dov Henis
(comments from 22nd century)
http://universe-life.com/
Posted by Dov Henis on November 18,2011 | 11:14 AM
I don't see how thinking you saw the first plane hit the tower on 9/11, when you really saw the second plane says that memory place tricks on us. Here's the footage that aired on 9/11: http://www.youtube.com/watch?v=Ys41jnL2Elk
Had it been labelled "this is the second plane" then we might have some pretty conclusive evidence.
So far, the Challenger and 9/11 tragedies have been used to try to prove that memory is faulty. Which national tragedy is next?
Posted by Lynn Murphy on May 15,2011 | 02:38 PM
Neither Nader's nor Brunet's study as discussed in this article proves that memories can be reconsolidated.
Nader's studies shows that rats didn't react after hearing a tone. There are many possible explanations for this. Perhaps the emotional component of the memory was weakened, but the memory still existed. And rats aren't human beings.
Brunet's study stated "The treatment didn’t erase the patients’ memory of what had happened to them; rather, it seems to have changed the quality of that memory. “Week after week the emotional tone of the memory seems weaker,” Brunet says. “They start to care less about that memory.”
In other words, the memory was still there.
As per these studies, the theory of memory reconsolidation is unproven.
And it is quite different to give an animal an electric shock or a drug that interferes with a particular neurotransmitter just after they were prompted to recall the memory and then to compare this to simple suggestion or misleading questions in humans.
The Loftus study as quoted in this article questioned peripheral memories, but not the major important details of the memory. Some memory theorists have believed that peripheral details may be subject to manipulation but the major details are not.
The accuracy of Loftus' work has also been questioned, see http://users.owt.com/crook/memory/
A good resource on the neurobiology of memory is http://www.trauma-pages.com/a/vanderk2.php which discusses the stability and accuracy of memories of stressful events
Posted by E. Stricker on May 14,2011 | 02:52 PM
Modern science is very confused about the laws of the structure of memory .
Posted by demetrios corinthius on May 10,2011 | 02:11 AM
I think those spending time on 'doubt' of footage played on September 11th are missing a simple part of the point made and may benefit from some simple clarification - yes we ALL saw footage ON September 11th, of the SECOND plane hit. We all saw that. We all remember where we were when we saw it. We ALL saw the damage of the first plane and the footage of it. What the article is saying is that the footage of the FIRST plane in flight and then ACTUALLY IMPACTING the first tower wasn't shown until the next day.
Now you can focus on the rest of the article:)
Posted by A McKinley on February 23,2011 | 04:09 PM
Seems to add support to the concept that hindsight is 20/20.
Posted by Don on November 18,2010 | 11:38 AM
Memory, a word so simple an issue as complex and covers language, intellectual ability or simple facts of daily life, memory, intelligence gives us is a concept that covers too much from a scientific sense, bringing it to everyday life. Speaking of memory must say that it is a very complex subject and many authors present different theories about its operating structure. We can say that memory is not one, but there are several types of this, talking about these types of memory often helps to understand that humanity forgets things, or why the call in his mind and no one understands q is that synaptic activity in long-term memory is faster, so the memories come back to the subconscious mind even though this event has already occurred for some considerable time. Constantly exposing our memories, or rather recalling an event sometimes causes varied each time the fence remember every memory modifying modifies the memory, but this does not seem to bring a big problem in people so that any event that is traumatic for their lives changed and eventually he will forget it, avoiding its own suffering in the future. The blog covers topics essential to the neurological study of people also need to expose these issues for society to be educated and learn to know their behaviors and attitudes, we all take to make real awareness of the importance of the concept of memory in our lives, without the need for scientists, but only to know our body and its reactions and ways of relating to our environment.
francisca andrade
maria jose cañete
students of catolica maule university
Posted by maria jose and francisca on July 29,2010 | 11:49 PM
Very Interesting.
Posted by Sonya on July 1,2010 | 01:27 PM
The 9/11 example seems to point to a process of restructuring a sequence of events as new information is attained. Also, the media reconstructed the sequence of events for us as they attained new information.
Posted by Oster on June 7,2010 | 12:17 AM
Now thwy can give the propranolol to the unfortunate rats to help them get over their trauma - yeah, right. Doesn't this research also knock a last nail (if one were needed) into the wretched business of psychoanalysis?
Posted by cavall de quer on May 16,2010 | 11:06 AM
Kyle, your wife sounds alot like me and I hope you are not as dishonest with her as most people are with me Maybe she is really being threatened or feels it or senses it I have the same problems she does and everyone feels I am being childish, selfish,hateful, and paranoid or hearing things But they fail to admit what I know most of the time I refuse to believe my hearing is that bad or I am the most horrible person around Too many people thrive on retaliation and harrasing these days Many times, it is the victim who suffers instead of the perpertrator I can't even get help for my emotional response to this disorder in my daily life because the health field considers I just need to look on the bright side I'm sure you're wife would know what that feels like also I hope she is not in the same pre dicament I am and that is I am not neurotic so much as no will be truthful with me
Posted by D K on May 13,2010 | 01:25 PM
Consider this true, personal history of an elderly woman:
Kyle is right on target about "remembering" and retelling over and over and over events that are absolute lies to other people....and how it affects the memories of some of those other people. [Our politicians are masters of this]
"My ex-husband, a convicted felon, thief and murderer, told our younger daughter that he went to prison because his ex- wife was a harlot who slept "with every man in town" over and over and over. Now at 46 she is an alcoholic who gets drunk and calls me to repeat these lies (as his demonic self has this woman under his control.) Her older sister, also raised by me alone, is a successful, international business woman! She wrote him in prison that she never wanted to see him again...and probably had much less contact in her adult life with this human devil."
The demonic influence exerted over another human is tragic. Could it possibly be resultant in some way by Jung's theory of supernatural universal conscience?
Posted by Ann on May 11,2010 | 12:03 PM
I learned about the 911 attacks when my daughter called me that morning to ask if I was watching the television. When I said "No, I am having my first cup of coffee late today" she had me turn the TV on while we were on the phone. We watched "together" as the second plane hit the tower, while news cameras were focused on the damage done by the first plane. We had been discussing whether this was a terrible accident or something intentional and I remarked when the second plane hit "Oh, no, it's real-we're under attack!" Three quarters of folks who experienced similar events can't be that wrong. Might be worth checking the records of the major news networks!
Posted by Robin Burns on May 6,2010 | 11:59 AM
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