The Fallibility of Human Memory


Jonah Lehrer writes about a new study of human memory and storytelling, particularly about how unreliable our memories often are, especially after years of recounting the story. Over time, we tend to embellish and borrow details from other stories, resulting in part fact and part fiction — and often even using the memories of others as our own, all while entirely believing it ourselves.

Particularly interesting is how our memory evolves in response to other people in social contexts, how the interaction of our memories with those of our friends and family can result in much better stories but far less accuracy.

The reason we’re such consummate bullshitters is simple: we bullshit for each other. We tweak our stories so that they become better stories. We bend the facts so that the facts appeal to the group. Because we are social animals, our memory of the past is constantly being revised to fit social pressures.

The power of this phenomenon was demonstrated in a new Science paper by Micah Edelson, Tali Sharot, Raymond Dolan and Yadin Dudai. The neuroscientists were interested in how the opinion of other people can alter our personal memories, even over a relatively short period of time. The experiment itself was straightforward. A few dozen people watched an eyewitness style documentary about a police arrest in groups of five. Three days later, the subjects returned to the lab and completed a memory test about the documentary. Four days after that, they were brought back once again and asked a variety of questions about the short movie while inside a brain scanner.

This time, though, the subjects were given a “lifeline”: they were shown the answers given by other people in their film-viewing group. Unbeknownst to the subjects, the lifeline was actually composed of false answers to the very questions that the subjects had previously answered correctly and confidently. Remarkably, this false feedback altered the responses of the participants, leading nearly 70 percent to conform to the group and give an incorrect answer. They had revised their stories in light of the social pressure.

The question, of course, is whether their memory of the film had actually undergone a change. (Previous studies have demonstrated that people will knowingly give a false answer just to conform to the group. We’re such wimps.) To find out, the researchers invited the subjects back to the lab one last time to take the memory test, telling them that the answers they had previously been given were not those of their fellow film watchers, but randomly generated by a computer. Some of the responses reverted back to the original, but more than 40 percent remained erroneous, implying that the subjects were relying on false memories implanted by the earlier session. They had come to believe their own bullshit.

Here’s where the fMRI data proved useful. By comparing the differences in brain activity between the persistent false memories and the temporary errors of “social compliance” the scientists were able to detect the neural causes of the misremembering. The main trigger seemed to be a strong co-activation between two brain areas: the hippocampus and the amygdala. The hippocampus is known to play a role in long-term memory formation, while the amygdala is an emotional center in the brain. According to the scientists, the co-activation of these areas can sometimes result in the replacement of an accurate memory with a false one, provided the false memory has a social component. This suggests that feedback of others has the ability to strongly shape our remembered experience. We are all performers, twisting our stories for strangers.

And over time, of course, those initially embellished stories become our memories. We remember it the way we told it rather than the way it actually happened. And Lehrer cites 9/11 as a perfect example:

We are so eager to conform to the collective, to fit our little lives into the arc of history, that we end up misleading ourselves. Consider an investigation of flashbulb memories from September 11, 2001. A few days after the tragic attacks, a team of psychologists led by William Hirst and Elizabeth Phelps began interviewing people about their personal experiences. In the years since, the researchers have tracked the steady decay of these personal stories. They’ve shown, for instance, that subjects have dramatically changed their recollection of how they first learned about the attacks. After one year, 37 percent of the details in their original story had changed. By 2004, that number was approaching 50 percent. The scientists have just begun analyzing their ten year follow-up data, but it will almost certainly show that the majority of details from that day are now inventions. Our 9/11 tales are almost certainly better – more entertaining, more dramatic, more reflective of that awful day – but those improvements have come at the expense of the truth. Stories make sense. Life usually doesn’t.

I actually don’t have vivid memories of 9/11. I’ve never really told a tale about it. I remember where I was — at work — and I remember everyone gathering around the TV that morning with others, watching the second plane hit. And I remember just being in shock. But I don’t have vivid memories of what I was thinking. I wish I’d had some immediate profound thought on the situation, but I didn’t. Or at least I don’t remember it if I did.

Comments

  1. D. C. Sessions says

    We bend the facts so that the facts appeal to the group.

    And now consider the reality disconnect we see in the right-wing echo chamber.

  2. Abby Normal says

    And now consider the reality disconnect we see in the right-wing echo chamber.

    It’s not just the right wing. I’ve noticed everyone seems to do this but me.

  3. anandine says

    The thing is, each time you remember something, you reconsolidate the memory in the brain. If somebody asks what color the guy’s hat was, then the next time you may well remember that he had a hat on, even if he did not.

    This means you can never trust any memory, no matter how strong it is.

  4. Aquaria says

    I actually don’t have vivid memories of 9/11. I’ve never really told a tale about it. I remember where I was — at work — and I remember everyone gathering around the TV that morning with others, watching the second plane hit.

    Maybe some of us don’t need to embellish it, because we haven’t been going over and over it in our minds.

    However, I do have a pretty good reason for remembering where I was, because my son and I were at the DMV registering the car, and I remember seeing smoke coming out of one of the towers. I was too far away to see the scrawl, and went about my business. I pretty much blew it off once the clerk called my name.

    It was only when we got home and my son turned on the TV to see what had happened that we learned the awful truth.

  5. Aquaria says

    Argh. We saw smoke coming out of the towers on one of the TVs they had for people in line. That’s where I saw the smoking tower.

  6. says

    One group of people that has always struck me as being shameless embellishers is preachers, particularly those who like to tell entertaining stories from their personal lives to illustrate their messages. I still remember a couple of such stories told to me by ministers from over 30 years ago — the type of tale whose punchline always gets a laugh, but then you’re left thinking, did that really happen?

    Larry King’s old favorite, Pastor Joel Osteen, strikes me as one of those people. His stories aren’t particularly funny or entertaining, but if I recall correctly, he seems to come up with several pertinent tales from his life every sermon. The thousands in the congregation seem to lap it all up, but I’m just left thinking, “nobody leads a life that is so conveniently packaged into entertaining and illustrative little tales.”

    But back when I used to watch TBN with slack-jawed incredulity as a newcomer to the USA, the undisputed master of the embellished tale was televangelist Jesse Duplantis. His personal stories can leave you rolling in the aisles even if you’re not a believer and you know they have got to be gross exaggerations of what really happened, if the weren’t downright fabrications. Another example is one of Ed has featured on his blog before — Pastor Rod Parsley.

    Ironically, one give away with Duplantis and others like him is how frequently they tell you that it’s the “God’s honest truth”.

  7. ManOutOfTime says

    I remember a guy in 6th grade told me a story that was so funny, and he told it in such detail, about something he did in 4th grade, by the end of middle school I had told it so many times I genuinely believed I was there. I argued it with him and he finally reminded me we did not go to the same elementary school. Just goes to show you. Brains is stupid!

  8. The Christian Cynic says

    One of the classes I teach is world literature, and I teach a wonderful excerpt from Isabel Allende’s memoir My Invented Country where she makes a similar point about memory:

    I can’t pretend to know what part of my memory is reliable and how much I’ve invented, because the job of defining the line between them is beyond my ability. My granddaughter Andrew wrote a composition for school in which she said that she liked her “grandmother’s imagination.” I asked her what she was referring to, and without hesitation she replied, “You remember things that never happened.” Don’t we all do that? I have read that the mental process of imagining and that of remembering are so much alike that they are nearly indistinguishable. Who can define reality? Isn’t everything subjective? If you and I witness the same event, we will recall it and recount it differently. Comparing our versions of our childhood that my brothers tell, it’s as if each of us had been on a different planet. Memory is conditioned by emotion; we remember better, and more fully, things that move us, such as the joy of a birth, the pleasure of a night of love, the pain of a loved one’s death, the trauma of a wound. When we call up the past, we choose intense moments—good or bad—and omit the enormous gray area of daily life.

  9. Nemo says

    I have now and then caught myself re-imagining a memory the way it “should” have happened, and forced myself to remember it the way it really was (or as close to that as I can manage).

    I first heard about the attacks from Slashdot, of all things. That’s my story and I’m sticking to it. Not terribly interesting, is it?

Trackbacks

Leave a Reply