Why Your Memory Seems Bad (It’s Not Just Age)
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Summary
Do you sometimes walk into another room in your house to get something but then can t remember what it was you wanted? Do you sometimes forget about an appointment or struggle to remember someone s name? You may have chalked these lapses in memory up to getting older, and age can indeed play a role in the diminishing power of memory. But as my guest, Charn Raghunath, will tell us, there are other factors at play as well.
Transcript
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Brett McKay here, and welcome to another edition of the Art of Manliness podcast.
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Do you sometimes walk into another room in your house to get something, but then can't
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Do you sometimes forget about an appointment or struggle to remember someone's name?
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You may have chalked these lapses in memory up to getting older, and age can indeed play
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But as my guest will tell us, there are other factors at play as well.
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Charn Raghunath is a neuroscientist, psychologist, and the author of Why We Remember, Unlocking
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Today on the show, Charn explains how factors like how we direct our attention, take photos,
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and move through something called event boundaries all affect our memory, and how our current
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context in life impacts which memories we're able to recall from the past.
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We also talk about how to reverse engineer these factors to improve your memory.
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After the show's over, check out our show notes at awim.is slash memory.
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So you are a neuroscientist, and you've spent your career 20-plus years researching memory.
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And we're going to talk today about why we remember some things, why we forget other stuff, and
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But after I read your book, one of the big takeaways I got from it was that memory is more
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than just an archive of our past, that actually memory shapes our day-to-day lives.
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So how does memory influence our lives beyond just being able to recall events?
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So one just very kind of simple example would be, let's say you wake up in a hotel room, right?
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Your first question as you wake up is you're a little disoriented, and probably without even
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thinking about it, you're having this moment of, where am I?
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And just to situate yourself in time and space, right?
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It's like you can look around, you know where you are in the room, but where is this room?
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It could be in like a prison somewhere, or it could be in like a resort.
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And so you have to rely on memory just to get to that point to dig you out of that hole
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So let's take a slightly more complex example now.
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Let's say, for instance, you are trying to choose which restaurant you want to go to,
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and you have a usual restaurant that's pretty good, but then lately they changed the menu.
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And the last time you went there, you had a terrible meal.
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So you can use memory to basically say, you know what, I'm going to go to someplace different
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And then we can take something like a big choice.
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So I decided to go into research in cognitive neuroscience, but my training was in clinical
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And I actually had the chance to do a clinical internship in which I could have been on a
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career path to make lots of money in a clinical career.
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And when I look back on that decision, what I asked myself was essentially, what are the
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kinds of moments that I feel most comfortable in, that I'm happiest about?
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When I thought about the instances in which I was in the clinic, I thought, okay, I have
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I have to be on when people say there's a lot of pressure because if I don't get things
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bad things can happen versus the times that I could remember from being in research where
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I was staying up late, drinking beers and eating pizza in the lab while we were working
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And the people that I hung out with in the lab versus the more kind of formal environment
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And so these hard life decisions are very, very complicated.
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We're making them based on insufficient information.
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And so we rely on memory to give us that data that we need to make these decisions about
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And as we'll see in this conversation too, memory is connected to a lot of other things
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in our lives that we might not think are connected to memory.
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The ability to imagine things, that's connected to memory.
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How we situate ourselves not only in place, like that example you gave, you wake up in a
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And then the follow-up question is, what can that answer tell us about how memory works?
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When we look at the design of the brain, what you see over and over and over again, whatever
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system you look at, is that the brain is optimizing to make the most of a little bit
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And so what I mean by that is if we see the world, we're not literally looking at everything.
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We're only grabbing little bits and pieces of the world with our eyes by just moving our
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eyes and focusing in different places and then assembling that into a meaningful picture.
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So we know that even our ability to perceive the world is limited and our ability to hold
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So what makes things memorable and what makes things grab our attention, there's a high relationship
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They're often things that are biologically important.
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So something that you'll probably find this, I imagine yourself, Brett, if you look back on
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things in your life, you probably remember the first things that will come to mind will be
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Things that are very emotionally, you know, they're exciting or times where you were scared
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And these are biologically important moments where there are chemicals in the brain that
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promote plasticity that are released during these moments.
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So that right off the bat tells you something about why some events are memorable is because
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Other events that would be also important would be things that are new or things that are
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So we often remember these events that really surprise us because they stick out.
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And some of that is related to a phenomenon I'll get into with regards to interference.
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But some of it is also when we're surprised or when we're in a brand new place that we've
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Again, there's these release of neuromodulators, these chemicals in our brain that promote
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And another key factor, as I mentioned, is the fact that memories compete with each other.
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So I think intuitively we might think of memory as being like I store a bunch of files in my
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And more or less, if I store 10 files or if I store 20 files, it doesn't make a difference.
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In human memory, the memories are competing with each other.
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And so if I'm trying to remember Brett, let's say, your name, I meet you sometime in person.
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We go into the real world as opposed to the virtual world.
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Well, remembering Britt is going to be complicated because I've just learned about Brett.
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And there's going to be this interference between them.
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So the way that memories can survive that competition is if there's something distinctive
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that makes this memory different from something else.
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So if I had something about your name and I could tie it with something interesting about
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you that I learned and make that all into one big story, for instance, then now all of
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a sudden you're very, very different from Britt because Britt's just sound that I heard.
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And this is the way in which memories can stick around is if we're attending to something
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that allows us to capture what's unique about this moment in time.
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So the sights, the sounds, the smells, emotions, something that you think about that's unique.
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Does our brain store memories in a specific part of the brain?
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Well, this is a very tough question to answer because essentially it comes down to what is
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And so there's many different ways memory can be manifest.
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One is your ability to just know, call upon facts, general knowledge that you have about
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And then there's your ability to remember specific events in your life, like episodic memory.
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So I know that Def Leppard was a British metal band that played very melodic songs in the 1980s,
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but that's different than my memory for seeing them in the round during the Hysteria tour,
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But nonetheless, that's an episodic memory from one point in time.
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And so those kinds of memories differ from each other.
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Now, the hippocampus is an area of the brain that's known to be very important for forming
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And it doesn't do it by itself, but what it does is it ties together all of these different
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parts of the brain that are processing the different kinds of aspects of the semantics
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So a lot of what people think of when they think of the memory loss, for instance, that
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you see in the earliest stages of Alzheimer's disease, that's related in part to the loss
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Because what happens is people start to lose this ability to form new episodic memories.
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They still have knowledge of who they are, all the people they know in those early stages,
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but they lose this ability to form new episodic memories.
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And so that's why the hippocampus is such a big player in memories, because it plays this
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role in just arbitrarily saying, in some ways, the hippocampus, I mean, if we were to pretend
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the hippocampus is a person instead of a brain area, you could say, well, it's being deliberately
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It's not thinking about why things should go together.
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It's just saying, hey, I happened to see Brett in the pub while the song was playing in
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So the hippocampus is involved in episodic memories.
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Something that you've researched a lot and found, and it's been groundbreaking, is the
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People might be familiar with the idea that the prefrontal cortex can be used as short-term
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The analogy is the prefrontal cortex is like RAM.
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So if you need to temporarily remember something, prefrontal cortex can take that, but for longer
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What your research has found is no, the prefrontal cortex actually plays a bigger role in those
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Yeah, I think that I'm really glad you brought up that RAM analogy because I think that was
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very popular for a long time in psychology that we used to think of humans as being like
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computers in this very kind of straightforward way, but we're not.
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What the prefrontal cortex seems to be about is, it's kind of a, again, I'm going to use
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these analogies just to keep things simple, although I hope people with a more scientific
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But a lot of people use the term executive to describe what the prefrontal cortex does.
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And what that means is, you know, an executive who's running a company really has no useful
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They're not like, you're not going to trust them with the accounting, you're not going
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to trust them to like handle the mailroom or anything like that.
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But their job is really to oversee everything coordinated towards a common goal.
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And that's what the prefrontal cortex is all about.
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So for a long time, people used to think, oh, the prefrontal cortex doesn't do anything
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because it's not, people could lose a prefrontal cortex and they would still walk and talk and
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But they couldn't function in the real world because they had no ability to use that information
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And so you brought up this idea of short-term memory.
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And so part of the idea of being able to hold a phone number, say, in short-term memory,
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like if I give you a phone number or if I say, hey, here's your temporary password, I need
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you to reset it so that you can get back into your bank account.
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But to do that, you have to keep out, keep yourself from being distracted, right?
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So there's a kid crying in the background, or maybe you're getting a text alert on your phone
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and you have to suppress those distractions to focus on what's relevant.
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And that's where the prefrontal cortex comes in.
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But that same ability is also what allows you to be present in the moment and focus on what's
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important, like where I put my keys or where I put my phone, as opposed to the things that may
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be less important but could grab your attention, like the sound of a dog barking or a kettle
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whistling or something, things that you need to take care of.
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But they're not necessarily related to these other long-term goals.
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And so this idea that the prefrontal cortex directs our attention to stuff that we want
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to remember, and if we're distracted, we might not remember that thing, that explains like
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why we forget, like where did I put my keys, where did I put my wallet?
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Because you just, you weren't, your prefrontal cortex kind of checked out when you just dropped
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them on the counter and you weren't paying attention.
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So it's just like, yeah, we're not going to remember that.
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And so, and sometimes what happens is our prefrontal cortex isn't checking out, but it's actually,
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We'll go, oh, yeah, I'm going to be like, you know, I'm walking in the door, I've got
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But then I just decide habitually to check my email or something.
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And so the prefrontal cortex is saying, okay, let's shift gears.
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And so the next time when you go back to your keys, you're already a step behind because
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your prefrontal cortex has to use all these resources just to shift back from the email
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task back to whatever it was you were doing when you opened the door.
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And so as a result, our resources become too depleted, spread too thin, and we can't focus
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So sometimes the prefrontal cortex is there, but we misdirect it because we have bad habits.
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I think you highlighted some research how constantly using social media, that can inhibit
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memory because your prefrontal cortex has got all this information, just you're blasting
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it, and then it can't remember stuff you actually want to remember.
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So you can be blasted both by switching between these things.
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And again, a lot of this is under our control, so to speak, meaning that we don't have to
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Like right now, if I was being sloppy, I would be checking social media in between points in
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our conversation, which would be horrible for my ability to remember our conversation
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later on, which is why I turned off all my alerts and I went into focus mode for this
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conversation because otherwise I'd be having this conversation.
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And then somebody would say, hey, what did you do today?
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And I'd be like, I was on this amazing podcast, but I can't remember anything about it.
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And this might explain like why as you get older, I mean, there's a couple of things
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going on as you get older, why your memory feels like it's not as sharp.
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But I just think as you get older into your 30s and your 40s and your 50s, you have a lot
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more going on in your life, a lot more stuff to keep track of, keeping track of your kid's
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schedule, your work schedule, things that need to be done on the house.
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And so, yeah, you're probably going to forget that your glasses are on top of your
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You know, so as we get older, there's a bunch of things that happen.
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So one is that we have a lot of stresses, we have a lot of pressures, and we have a lot
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of competing things and deadlines and so forth.
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And so when we're under stress, the natural response of the brain is to downregulate the
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You want to go into more of a responsive mode rather than a mode of planning and deliberation.
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And so we're now compromised because of that stress.
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But then on top of it, as we get older, on average, the prefrontal cortex shrinks a little
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It's not functioning as efficiently as it should.
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And then, you know, we're maybe having some health issues.
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Maybe you're not sleeping as well as you used to.
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And so all of these factors can compromise the frontal cortex even more.
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So one of the things I think a lot about is how modern life is just optimized to deplete
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our mental resources and put us in the state of perpetual amnesia.
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Okay, so the prefrontal cortex plays a role in memory by directing where we place our attention.
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And then when we don't give something sufficient attention, we can't remember it.
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So, you know, if we got a lot going on in our lives, we tend to be forgetful because there's
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just too many things to pay attention to, it overwhelms the prefrontal cortex.
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And then when you're multitasking, you know, task switching a lot, you can't give anyone
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task enough attention to remember what's going on with it and do it well.
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And then all these things, it can cause stress and that can deplete the strength of the prefrontal
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cortex as well as other things like lack of sleep.
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Something related to this is how the use of smartphone cameras affects how we remember
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So on average, the research shows pretty significantly that when we use cameras to document our lives,
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we actually have a paradoxically lower memory for those events.
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And I think people have this intuitive idea that if I take a picture of this event, I will
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But what often happens is people don't go back to the pictures, right?
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And then on top of it, we're mindlessly documenting these things.
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And you can see this with the rise of Instagram walls everywhere, right?
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So it becomes no longer about the experience, but about the picture.
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And so what happens is, is that people tend to have a poor memory for these experiences when
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they've been focused on taking the pictures and posting them.
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So you could be more selective in the way that you take pictures and use the camera as a tool
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for grounding you in the moment and say, what's really going on here?
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And then selectively take pictures that are planting cues in your mind for later on being
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Because that's what a lot of memory is, is if you have the right cues, some distinctive
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thing that you're seeing or smelling or hearing, that's what allows you to go back and revisit
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And one study found that if people are in that kind of condition, you can actually improve
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Another way you can do it is by actually going back to those pictures.
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So we can think of an Instagram story or a Snapchat post as being a metaphor for how
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photos actually have this amnesic quality where you post something and then two days
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And this is what I think we often do with our photos.
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But if you actually, one of the things I do like is what's called Facebook memories,
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where they put on a photo that you haven't seen in years, but you posted it a while back.
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And the act of recalling that memory now makes it more accessible later on.
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So the act of remembering makes it more memorable.
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So if you're going to take pictures, I think going back to what we were saying about the
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role of the prefrontal cortex in memory, if you're just focused on taking the perfect
00:19:28.900
picture and thinking, oh, this would be great for Instagram.
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You know, the way you're directing your attention, you know, putting it on the picture taking
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And because of that, you're not going to remember the experience as much.
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But you could, if you direct your attention differently, even while taking a picture,
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that can enhance your memory if you want it to.
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I would say that if you can use your prefrontal cortex, say, if my goal is to have a memorable
00:19:56.820
experience, I can actually, first of all, think about what's in front of me.
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Think about the sights and the sounds and the smells and so forth and immerse myself
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But then when I do take pictures, you can actually ask yourself, what would be a good
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What are the points in this moment that I want to remember?
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What are the points in this moment that I don't want to document?
00:20:19.680
I think lots of times we just take pictures without ever even thinking, is this the memory
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Because ultimately, once we start taking these pictures, those pictures will have a
00:20:34.480
So how many times have you taken a vacation and you take pictures and the events that
00:20:38.740
you remember later on are those events that you photographed and the ones that you didn't
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So that's, I think, part of it is the camera can be a tool.
00:20:52.920
And again, if you use your frontal cortex to say, what do I want out of this experience?
00:20:56.640
The camera can be a tool to get it, as opposed to a distraction that just takes you away from
00:21:03.340
So going back to this idea of episodic memory, this is sort of remembering events in our lives
00:21:09.740
Why is it that we have a harder time with episodic memory as we get older?
00:21:20.820
Your prefrontal cortex shrinks as you get older.
00:21:22.780
But I mean, I've noticed this in my own life, and I think you talk about this in the book.
00:21:27.620
I can remember stuff from when I was middle school through age 30, like very vividly.
00:21:40.960
But then after age 30-ish, things are kind of like, I kind of remember doing that, but
00:21:45.940
it's not as in much detail as those teenage years.
00:21:50.600
Well, this is something that's very, very common.
00:21:53.900
In fact, memory researchers have a name for it, which is the reminiscence bump.
00:21:58.460
And the idea behind the reminiscence bump is that if you just plot the number of memories
00:22:03.600
that people will report, if you ask them about different times of their lives, and you just
00:22:07.720
make a little graph out of it, there's a big bump in the graph from the years between
00:22:14.900
And one big reason is that that's when our sense of who we are is actually emerging.
00:22:20.980
And so the experiences that we have during that time period are very tied to our sense
00:22:27.440
And that's the time when we're forming our tastes in music, in food, and we're finding
00:22:33.200
the friendships that help define us and so forth.
00:22:36.380
And so we tend to call upon those memories more as a result.
00:22:40.480
And as I was saying, the memories that you call upon the most will be strengthened each
00:22:46.800
Another theory as to why we remember more from our youth is that memory is enhanced when
00:22:55.100
And when we're young, we've got a lot of novel things.
00:23:01.300
And so when the brain encounters that, its memory camera is like, oh, hey, this is novel.
00:23:10.340
So then when you look back on it, there's a lot of memory footage to unspool.
00:23:19.800
Each day, even year, it's just a lot like the last one.
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So when we look back, there's not a lot of memory footage to unspool.
00:23:33.180
So if you want more memories in adulthood, you're going to have to do more novel things,
00:23:39.960
We're going to take a quick break for your word from our sponsors.
00:23:48.580
So how can understanding how episodic memory works help us understand why it is when we
00:23:55.400
go into the kitchen for something, we forget why we went into the kitchen?
00:24:02.000
This is one of my favorite topics and actually something that we're studying a lot in my lab
00:24:07.980
Even though our lives are continuous, what happens is we tend to remember our lives as a series
00:24:14.600
of events, like I went to the kitchen, I went to someone's 21st birthday party, blah, blah, blah.
00:24:21.540
And so what we think happens is, is that as we go about our day, you're creating a little
00:24:27.940
story in your head that's, okay, so my job right now is to talk to Brett and answer this
00:24:34.980
I'm thinking of all these ways of answering it.
00:24:37.380
But then we move on to another question and I flush that information out.
00:24:44.260
And that time when I pivot from question one to question two is what we would call an event
00:24:49.700
It means that one event is over and another has begun.
00:24:53.060
And what we can see when we scan people's brains is at those moments, there's almost
00:24:57.140
a tectonic shift in the patterns of brain activity where you see this change in patterns
00:25:02.880
as people's story about the world changes in a moment.
00:25:06.560
And so what's interesting is, is that even the act of just moving from one room to another
00:25:12.540
So if I take a few steps right now, if I were just to stand up, take a few steps to my right,
00:25:17.620
I'd be in my room and then one more step and I'm crossing into the hallway.
00:25:21.780
And even though it's just another step, I would psychologically feel like I'm in a new place.
00:25:27.280
And that change in your spatial context is enough to create an event boundary.
00:25:32.780
And because context is so important for memory, that as episodic memories are so tied to a
00:25:38.680
time and a place, that in the time it takes me to go to the kitchen, now I've shifted across
00:25:45.900
And now when I go back and try to remember why I went to the kitchen, I have to engage
00:25:50.840
in this act of mental time travel to recall what I was doing back in that time period when
00:25:58.260
And that's why it's often helpful if you go back to the room you were in originally, you'll
00:26:06.580
So then what happens is for me personally, I'll go to the kitchen, I'll say, oh, what was
00:26:14.160
And then I come back to my office and I'm like, oh my God, I left my phone in there.
00:26:18.720
And I realized, okay, over the course of the past year, I've probably consumed thousands
00:26:23.220
of calories because of these damn event boundaries.
00:26:25.560
As I read about that idea about event boundaries, it made me wonder if this can help explain
00:26:32.040
whenever I read stuff on a digital device, like my smartphone with the Kindle app, I
00:26:36.980
don't remember as much as when I'm reading from a paperback book.
00:26:40.460
And I think it could be because when you're on a device, I could be on the Kindle app and
00:26:44.980
then immediately I can swipe over to Instagram or my email.
00:26:47.920
That event boundary, when I'm reading on my phone, it's just really porous.
00:26:51.800
I'm switching back and forth between events, so I'm remembering less about each.
00:26:57.420
But with a book, like a paperback book, there's a clear event boundary in its pages.
00:27:06.840
And I've noticed that whenever I read a paperback book, I remember it more.
00:27:11.180
I can find things and I can remember where some quote that I highlighted is.
00:27:15.160
I know which part of the book it's in, but I don't have that experience when I'm reading
00:27:20.700
Yeah, so there's definitely physical aspects of holding a book that are different than
00:27:25.560
the way we interact with a Kindle, for instance.
00:27:28.440
And so that can lead our reading experience to change, which is going to change memorability.
00:27:34.680
So one of the things that you mentioned is just the fact that if you're using a device
00:27:39.100
that has more than just a reading app on it, it's just so tempting to think of other things.
00:27:44.340
So when you pick up that device, your brain is considering all the possible tasks you
00:27:53.340
And I don't know about you, but if I ever go to a buffet, I'm eating one thing, but I'm
00:27:56.860
thinking about all the other things they could be eating, right?
00:28:01.920
And with a book, on the other hand, you have no choice.
00:28:05.420
And also with a book, there's a way in which there's a spatial sense of where the plot is,
00:28:12.120
because essentially there's a physical place for each word on this book.
00:28:16.700
But on the screen, it's a little different because every page appears on the same screen.
00:28:21.400
So it gives you a little bit more distinctiveness.
00:28:24.640
And all these factors put together, I believe, make it easier.
00:28:30.920
If I'm reading page 100, I often have to think back to what happened in page 70 in order to
00:28:38.520
be able to understand what's happening in page 100.
00:28:44.480
At least it feels more natural with a physical book because it's on a different page.
00:28:48.800
So I can think about it in a way that actually takes me back to a different place in a different
00:28:54.760
And what we've found is that actually there's a little burst of activity and a pattern of
00:28:59.860
activity in the hippocampus that tells us that people are mentally time traveling back
00:29:05.240
at these points where you can make a connection between the current part of a story and a
00:29:11.840
And so I think that act of being able to link things together and build them into a bigger
00:29:16.020
narrative is just mentally easier with a physical book.
00:29:20.780
Okay, so if you feel like your brain's kind of like, oh, I'm not remembering as much,
00:29:41.200
You have this chapter about the role that imagination plays in memory.
00:29:50.580
It was just so much fun because it allowed me, one of the things about writing this book
00:29:55.080
that was so much fun is I got to take a beginner's mind and start to look at things that I'd seen
00:30:00.280
in different things that I had read and put it together in a new way.
00:30:04.500
And so there's a very old idea going back to a researcher named Bartlett in 1930, where
00:30:10.920
he argued that we don't replay the past, but we really create what he called an imaginative
00:30:17.840
And by that he means that we don't play the past, we actually imagine how the past could
00:30:24.240
It's like instead of replaying it, we stage a play in our mind of how it could have gone
00:30:29.060
And so we do get some details, but then we use imagination to fill in the blanks and add meaning
00:30:39.020
And then in neuroscience, this idea really took off about 15 years ago, that we actually
00:30:48.900
That is, when we imagine things, they're not coming out of thin air.
00:30:52.200
They're based on this combination of all these semantic knowledge that we have and then all
00:30:58.300
these little episodic memories, these random bits of experience that we've had at different
00:31:02.860
moments in our life that allow us to anticipate and imagine things that have never happened
00:31:13.440
If memory is us just imagining how things might have gone, how do we know if what we're
00:31:19.080
remembering actually happened, that we're not just imagining it?
00:31:23.200
This is one of the coolest things about science, when somebody comes up with a problem that
00:31:31.560
And so my old advisor, Marsha Johnson, just came out with this as a young researcher in
00:31:38.020
She just said, how do we tell the difference between imagination and things that we've
00:31:45.360
A memory for something that happened and a memory for something we just thought about
00:31:51.380
And so the way that we have to do it is, again, surprise, you have to use your prefrontal
00:31:57.240
cortex to do a little bit of extra detective work.
00:32:01.200
And so what that involves is saying, okay, when I remember this thing, what are the bits
00:32:07.680
Are they things that I can see, or are they things that I can hear, or something that gives
00:32:18.760
So I don't know about you, but for me, I have these issues where I ask myself, did I send
00:32:26.000
that email, or did I just think about sending the email?
00:32:28.880
Did I take my medicine today, or did I just think about it and then get distracted?
00:32:33.180
And I have to actually ask myself, okay, can I feel myself pushing the send button?
00:32:38.320
Can I visualize myself, or can I taste like putting the medicine in my mouth and drinking
00:32:45.340
And if so, do I bring back a sense of today versus some other day?
00:32:49.520
And so those kinds of sensory experiences ground us in things that we've actually experienced
00:32:56.340
But the information that we think about could very easily be imagined.
00:33:00.320
And then also, whenever we're doing that imagining memory thing going on, like other stuff might
00:33:07.620
mix in as we're trying to recall a memory of our childhood.
00:33:11.160
There might be something that we picked up, like we read a book or something, and we saw
00:33:15.440
a movie, and we unintentionally spliced that into the childhood memory.
00:33:20.100
And it might turn into something that actually, that's not how it happened.
00:33:24.200
Yeah, and often, I mean, we need this because it's this less is more principle that we're
00:33:30.640
using schemas as the scaffold for our episodic memories.
00:33:34.720
So we don't have to keep rebuilding our memories from scratch.
00:33:37.680
If I went to a cafe every Monday and met up with a different friend, if I formed a blank
00:33:44.120
memory of that every time, I would be wasting enormous amounts of resources when instead I could
00:33:51.320
just take all my knowledge about what generally happens in cafes, and then tack on to that
00:33:56.460
the specific details of what I did this week versus what I did last week.
00:34:01.080
Now, the problem is, is that our schemas allow us to fill in those blanks, but sometimes we
00:34:08.000
And then what's worse is when we recall those events and we fill in the blanks incorrectly,
00:34:12.540
now that new information can creep into our old memory because the memories get transformed
00:34:19.160
And so that's why often people's, when they tell the story of something that happened in
00:34:23.340
their childhood over and over and over again, or your parents probably do this, what happens
00:34:27.960
is that they get more and more of these little errors that start accumulating.
00:34:33.500
Does this idea explain why sometimes people confess to crimes they didn't commit?
00:34:40.160
Yes, because what you can typically do in these interrogation situations, and there's actually
00:34:46.260
manuals that there's a manual called the read manual that talks about an interrogation method,
00:34:52.340
which relies on this, where what they do is they ask a person to, so first of all, you
00:34:58.940
start off with somebody who's an authority figure, like a police person.
00:35:02.320
You put the defendant under stress, and then you give them some misinformation, like somebody
00:35:12.160
So now there's a little bit of a seed of doubt planted in the person's mind, and they're
00:35:16.960
stressed out, so they're not applying this kind of critical thinking that the prefrontal
00:35:22.820
And then you ask them, okay, well, if you don't remember it, just imagine how it could
00:35:28.420
And so now they think about it, and if they have a vivid imagination, they might actually
00:35:33.160
be able to come up with a very vivid mental picture of how the crime could have played
00:35:37.360
And the next day you ask them, and now they remember something, but they don't remember
00:35:45.720
And so if you do this across multiple days while a person is stressed out, sleep deprived,
00:35:50.640
in case of it's some interrogation of somebody abroad, like what the CIA does with their enhanced
00:35:55.640
interrogation tactics, maybe they're being tortured.
00:35:58.860
And so as a result of all this, people can develop quite a rich false memory for things that
00:36:03.980
And this has been simulated in the lab by Julia Shaw and Elizabeth Loftus, and this has been
00:36:12.540
Okay, so memory can be squidgy because our imagination plays a role in recalling memory.
00:36:19.540
Here's another thing I've noticed in my life, and it goes to the squidginess of memory.
00:36:25.060
Sometimes you're talking to a friend, and you'd be talking about when you were in high school
00:36:29.640
or in college, and you say something like, oh, yeah, I remember you were really for the
00:36:34.120
war in Iraq, and I remember how adamant you were.
00:36:37.240
And the person, your friend says, actually, no, I wasn't.
00:36:41.240
I mean, I might have said some things, but I actually wasn't.
00:36:43.400
You're like, no, you seem pretty adamant about that at the time.
00:36:47.660
Do we sometimes change our memories in order to match how we see ourselves today?
00:36:51.980
So maybe we thought something in the past, but then our politics has changed or beliefs
00:36:55.420
have changed, but we update the way we remember things so that it matches how we think of
00:37:06.220
So our ability to recall anything in a given moment is based on who we are and how we feel
00:37:15.280
So just as if you hear the right song or if you're in the right place, you can access a
00:37:20.900
memory for a particular moment that matched up with that.
00:37:26.460
Likewise, when we're searching for information, the goals that we have and the beliefs that
00:37:31.340
we carry with us affect what we can pull out and what we can't.
00:37:38.640
So for instance, it could be something along the lines of you're having a fight with your
00:37:42.520
And so now all of a sudden you pull up all these things recently that they did to piss
00:37:49.640
Then you make up and then a week later, you can't remember what you even fought about.
00:37:53.440
All those other memories that popped up, right?
00:37:57.160
And so what changed was your mental context, this emotion, this intense emotion that you
00:38:04.880
So we have certain beliefs and we tend to find memories that are consistent with our
00:38:10.740
If my belief is the past used to be great and I was so cool when I was in high school, then
00:38:18.280
I'll remember all these great things that happened in high school, but I won't remember all the
00:38:24.660
And then finally, we view the world through a particular perspective.
00:38:28.020
And so we can actually access other information when we change this perspective.
00:38:32.760
So for instance, two people who are members of different political parties might watch the same
00:38:37.400
presidential debate and come away with memories of completely different experiences of who won
00:38:43.080
and who lost based on the little one-liners and so forth and the talking points that they
00:38:50.940
But people can switch perspectives and say, well, what if I was, instead of being a Republican,
00:38:58.540
They can start to pull up these exceptions that they might have normally missed.
00:39:01.920
Just like you can probably pull up information about the positive aspects of your relationship
00:39:07.940
with your partner when you're not fighting with them.
00:39:14.160
Are there any tips on how to make sure you're remembering things correctly and you're not
00:39:18.780
messing things up just so it updates and matches your current state?
00:39:24.660
I think one factor to keep in mind is just, first of all, how much you're going to search
00:39:30.020
for information and memory that confirms your beliefs.
00:39:32.580
So on average, people tend to think of them, recall memories that are more positive and
00:39:38.780
that make themselves look better than they really were.
00:39:42.340
So if I recall some experience from some time in my life, I might actually think of it,
00:39:49.380
think of an experience that's going to be more positive, but I'll also remember myself
00:39:53.620
in a way that's maybe been more of a positive role than actually transpired.
00:39:58.440
So being aware of these biases, I think, is the first step.
00:40:02.120
Another step is allowing ourselves the time to think critically.
00:40:07.100
And again, what often happens is we're under stress.
00:40:12.720
And it makes us very susceptible to misinformation.
00:40:18.800
But likewise, I think one thing we can do to help ourselves is surround ourselves by diverse
00:40:24.480
perspectives and give ourselves a chance to remember things from other perspectives and
00:40:29.720
think that maybe the way I see the world now is just one view of how the world could be.
00:40:35.580
What's one thing that people can start doing today to get more out of their memory?
00:40:42.700
What I would say is probably the one thing that I would say is be comfortable with discomfort.
00:40:49.900
And what I mean by that, and I don't mean like that necessarily, be a man, man up.
00:40:56.640
But what I do mean is that I think we often assume that memory should be effortless.
00:41:02.580
Things should just easily come to mind and we should be able to memorize things easily.
00:41:07.340
And you look at the kid who gets straight A's and you're like, oh, that person's smart.
00:41:13.460
But really, the person who's getting straight A's is not learning.
00:41:15.840
In theory, if you're learning, it means that you're actually struggling and you're failing
00:41:21.020
to recall things sometimes and that you can get the most learning by pushing yourself and
00:41:26.940
exposing the weaknesses in your memory so that you can then capture those weaknesses and fix
00:41:33.540
Likewise, if you want to be more creative, you need to expose yourself to sources of memories
00:41:41.540
If you just kind of expose yourself to gobs and gobs of the same media, whether it's reading
00:41:48.700
material or music or people who you interact with, and they're all from the same demographic
00:41:54.200
group, same culture, same beliefs, you might as well be ChatGPT.
00:41:58.540
You're not going to be that creative or interesting.
00:42:01.380
And if you want to be accurate and you don't want to be remembering things in a way that's
00:42:07.060
basically making you susceptible for manipulation, you need to surround yourself with sources of
00:42:12.340
information and people who have different beliefs, again, so that you can really constantly
00:42:17.380
challenge yourself to challenge your view of how the past transpired.
00:42:24.300
And all of those things can be uncomfortable, but they can also be sources of curiosity.
00:42:28.420
And curiosity is a major driver of learning and has enormous effects on the brain, as we've
00:42:33.920
Well, Char, this has been a great conversation.
00:42:36.360
Where can people go to learn more about the book and your work?
00:42:39.200
Well, you can definitely read my book, Why We Remember.
00:42:42.000
You can also go to my website, charnranganath.com, to get on our mailing list for more information.
00:42:48.660
And you can find me on Instagram, where we post periodically, including some tips about memory
00:42:57.420
Well, Char and Ranganath, thanks so much for your time.
00:43:06.240
It's available on Amazon.com and bookstores everywhere.
00:43:08.700
You can find more information about his work at his website, charnranganath.com.
00:43:11.960
Also, check out our show notes at aom.is slash memory.
00:43:17.040
Well, that wraps up another edition of the AOM podcast.
00:43:27.280
Make sure to check out our website at artofmanless.com.
00:43:30.980
And while you're there, sign up for our newsletter.
00:43:34.620
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00:43:37.460
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00:43:43.380
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00:43:47.480
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00:43:50.820
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