TranscriptQuestion: What is a "flash-bulb memory?"
Christopher Chabris: A "flash-bulb memory" is a memory that forms kind of as though a flash is going off in a camera and you imprint a picture in your mind of what’s going on at a particular moment in time. That was a term that was devised and coined in the 1970s by the late social psychologist, Roger Brown, who did a study on people's memories of the assassination of President Kennedy. And he found that people had extremely vivid memories of where they were when they heard about it, what they were thinking, doing, who they were with, what they did next. And he found also for other significant events, like the assassination of Martin Luther King, people had formed similar memories.
And he concluded on that basis that highly significant events sort of imprint themselves into your memory and you’re going to always remember them. It turns out that... and this is kind of a natural belief, and this shouldn’t surprise us. For example, we all probably have a pretty good idea where we were when we heard about the terrorist attacks on September 11, 2001. I have a good memory of it. I actually heard about it on "The Howard Stern Show," of all places, when I woke up, I was in graduate school, so I woke up late those days and I actually tuned into the Howard Stern Show, and that’s how I found out about it.
At least I think that’s how I found out about it. That’s how I remember it. When people have actually done clever studies on flash-bulb memories to look and see whether our intuitive beliefs about how accurate they are match up with their true accuracy, they find out that the flash-bulb memories are not really any more accurate than ordinary everyday memories.
One especially interesting study was done by Ulrich Neisser, who had also done, long ago, the study that inspired our gorilla study. He actually, after the Challenger space shuttle exploded in 1986, the very next day he went to a class full of students and had them write down all this information. Where they were, who they were with, how they heard about it, and so on. And then followed up several years later before they graduated college and had them recall it again. Found out that their recall, years later, did not really match what they had written down the day after, but their confidence was extremely high. They were sure that that’s exactly how they remembered it. They had no doubt, whereas, of course they couldn’t tell you what they were doing the day before the Challenger exploded or the day after the Challenger exploded, just like all of us probably have no memory of what was going on, on September 10, 2001. So, the thing about flash-bulb memories that really makes them sort of deceptive is that they’re no more accurate than ordinary memories, they’re subject to the same kind of distortions that just happen in time to all of our memories, but we’re more confident in them because they’re so vivid and they’re so detailed and we sort of place, really, unwarranted faith in them.
Question: If these kinds of highly vivid memories aren’t reliable, are any memories reliable?
Christopher Chabris: Memory is not a complete fraud, we do remember some things. It’s not as though everything in our memory is a distortion and inaccurate and so on. One thing that’s been learned from a lot of research on memory over decades is that memory for the jest of something, for the main idea, is much better than memory for specific details.
Memory for details can change and fade over time. Memory for sort of main ideas, themes, emotional experiences, probably nobody really misremembers how they felt on September 11, but they might misremember where they were, who told them about it, and details like that. Especially the farther away they are from the epicenter of events. But they’re not going to forget how they felt on that day as easily.
So, sort of the overall message often comes through, but the details can change and fade over time. The problem, of course, is that we don’t realize that. So, we can get into big arguments over the details of memories, who said what to whom, when did they say it? Exactly what was said before that, what was said after that. Think about how many arguments you’ve gotten into over the course of your life where that’s what’s going on and those are kind of silly arguments because nobody can really trust their memory as much as they claim to in the heat of the moment.
Question: How do errors in film continuity relate to illusions and memory errors?
Christopher Chabris: A surprising fact about memory is that our memories can be pretty weak even for things that just happened a couple of seconds ago, and really a timeframe when you would think that memory should be pretty good. It’s one thing for memory to fade after a few years, but it’s another thing to get completely erased after a couple of seconds. And a great example of how this can happen is shown in films every day. Every movie that you watch has what are called "continuity errors," and there are catalogues of these on the web. You can and type in any movie name you want and find all the mistakes that the film editors made. Now, sometimes they realize they were making those mistakes, but they knew that most people wouldn’t see them. and in fact, when you watch movies, you hardly ever notice a continuity error because you’re paying attention to the plot and the action and the characters and so on and you don’t notice that, for example, in the “Godfather” there’s a glass of wine on the table in one scene and when the camera comes back to it, it’s gone, and then when the camera comes back again, it’s back again. But those are really sort of failures of memory.
You looked at that scene and you felt like you were taking it all in, and then when you came back to it from a different camera angle, or from a cut, you didn’t bother to match up your previous memory to what was then on the screen afterward, or you didn’t even store as much detail about it in the first place as you thought you did. You might not have actually even stored the information about the wine glass even though you paid attention to it at the time.
So it’s one thing to pay attention to things and notice them, but it’s a whole other thing to get them into memory and this phenomenon of continuity errors and how many changes we can miss as a video cuts from one angle to the other, from one scene back to another, illustrates another aspect of the illusion of memory.
Recorded May 13, 2010
Interviewed by Austin Allen