When You Don’t Believe Your Past Self

Think back to a major moment in your life — something which you truly think you remember each and every detail about. Now, try to recall something mundane from that day, something unrelated to the main events of the moment. What you ate for breakfast, which shoes you were wearing, the weather, the day of the week, etc. Unless you have a savant-level recall, chances are your memory of that fact is, at best, a guess. And yet, you probably ate breakfast that day, you were likely wearing shoes, there was certainly some sort of weather and a fully-functioning calendar that day, too. Even in the most important moments of our lives, we can’t retain all the information. We keep the important stuff and fill in the blanks otherwise.

But where is that line between “important stuff” and “I think it was a Thursday and cloudy out?” It turns out that, even on days we think are seared into our memories, those memories aren’t very reliable. 

Actually, it’s worse than that. If one leading study is any indicator, not only do our memories kind of suck, but we can’t really deal with that fact. 

For horrible reasons, most of who were alive on September 11, 2001, can remember a lot about where we were and what we were doing that morning. If you were in the United States on January 28, 1986, you may be able to recall where you were as well — that’s the day the Challenger exploded on its ascent into space. Plug in just most other dates in the last fifty years, though and that’s not the case — you’ll have a hard time finding a group of diverse people who can all recall, to some degree, what they were doing on that day. For memory researchers, 9/11 and the Challenger were opportunities an opportunity to run experiments that are hard to replicate. 

The day after the Challenger explosion, Ulric Neisser, a psychology professor at Emory University, and his research assistant, Nicole Harsch, used their intro psych class for an informal study. They asked the class of 106 students to fill out a short questionnaire about their experience the day prior — where they were, who they were with, etc. when they heard the tragic news. Two years later, Neisser and Harsch repeated the survey with the same students to see if their memories were the same — and whether the students had confidence in the accuracy of their recollections. The New Yorker relayed the findings:

When the psychologists rated the accuracy of the students’ recollections for things like where they were and what they were doing, the average student scored less than three on a scale of seven. A quarter scored zero. But when the students were asked about their confidence levels, with five being the highest, they averaged 4.17. Their memories were vivid, clear—and wrong. There was no relationship at all between confidence and accuracy.

A formal study after 9/11 found similar results. A year after the terrorist attacks, a group of researchers from asked more than 3,000 respondents from a half-dozen American cities to write down their memories of 9/11 — where they were when they found out about the attacks, who they were with, etc. The research made the same requests of the same people a year later and then again in 2011, ten years after the attacks. And what they found (pdf of their paper here), similarly, was that stories changed over time. In an interview with 9/11 memories researcher Bill Hurst, author Malcolm Gladwell noted that, per the study, “60% of the answers changed over time.” And again, responders were confident that their recollections were accurate.

But as a general rule, it’s fair to say that the memories from 2002 are probably more accurate than the ones from 2011, right? Recollections made more contemporaneously to the events themselves are, as a general rule, more reliable than ones from a decade after the event. That doesn’t seem controversial. And yet, if you expected the study’s participants to accept this, you’d be mistaken. Many found the result unbelievable — as in, they didn’t believe their earlier memories were accurate. Gladwell and Hurst explain:

Gladwell: Take the flashbulb study done after the explosion of the Challenger space shuttle in 1986. The psychologist in charge sat down with people months later and showed them how differently they described things right after the disaster. He showed them what they actually wrote. 

Hurst: He says is it their handwriting and they say, “Yes, but I don’t know why I wrote that because it’s wrong.” “I agree it’s my handwriting. I agree I must have written that. But I don’t know why I lied, because I clearly remember I was in the dorm even though this piece of paper says I was in the cafeteria.” So this is the overwhelming confidence that people have. 

It seems that, in some of these cases, we’d rather feel right than actually be right. But we really can’t trust our currently-recalled memories over evidence to the contrary. 

And if we can’t, perhaps no one else should either. As the New Yorker article linked above notes, this could cause major problems in other contexts: “our misplaced confidence in recalling dramatic events is troubling when we need to rely on a memory for something important—evidence in court, for instance.” 


Bonus fact: In 2000, CBS began broadcasting reality TV show “Big Brother.” As summarized by Wikipedia, the show “follows a diverse group of contestants, known as HouseGuests, who are living together in a custom-built home under constant surveillance. The HouseGuests are completely isolated from the outside world and can have no communication with those not in the house.” This caused a problem on 9/11 — producers had to tell the cast members about the attack because, as Entertainment Weekly reported, one of the three finalists lost a cousin to the terrorists.

From the Archives: When the Cows Come Home: A nice story from the aftermath of 9/11.