May 17, 2021 • 23 mins
What if everything you experienced felt like you had already lived it before? Meet the people for whom déjà vu is every day.
It’s that moment when you mix up past and present, the real and the imagined, and you can no longer trust your senses. How is it that the world is the same but the experience is completely weird? It’s like tasting your own tongue. What is going on in the mechanics of your mind?
Welcome to Déjà Ville, a virtual world designed to induce déjà vu in order to understand what happens when memory and our senses, our past and our present, all get scrambled up together.
Deeply Human is a BBC World Service and American Public Media coproduction with iHeartMedia.
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Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:00):
I'm Dessa, the disembodied lady voice of deeply human Why
we do the things we do? We're about to set
off on an episode of deja vu? Why do we
get it? And how could it help you better understand
the workings of your own mind. I I don't remember
the first time, but I remember when they started happening
(00:20):
really frequently. I would be in math class or something
and suddenly everything would feel kind of off, like I
don't know, if you know, this feeling in your gut
that something's just wrong. I think I was probably fourteen,
and I started getting them on maybe a daily basis
by the time I was sixteen, a daily basis. Mm hm,
(00:46):
can you describe, like, if I met you at fourteen,
what's your vibe? You know? Do you have like pink hair?
Do you have like thick glasses? What's the vibe? Um?
Just picture Avril Levine. It's a little bit cringe e
but a bit of a skater girl, you know. So
that means like dark eyeliner. Did your mama you wear eyeliner?
(01:07):
She did? Yeah, straightened hair, dark eyeliner, band, T shirt.
I start to feel kind of fearful and have the
sense of dread, and I start to feel really sick
to my stomach, and it starts building like there's there's
something that's going to take hold of me, and um,
(01:27):
I really don't want it to, so I try to
focus on what's going on around me, but it starts
invading my head more and more, and then it I
get to this point where it feels like everything that's
currently happening has already happened. And then it sort of
feels as though I can remember the history of the universe.
Of course I couldn't give any details of what that
(01:48):
even meant, but at the time, I like it, fully
convinced that that's what I'm feeling. I can remember everything
that's ever happened and everything that will ever happen, and
it's all tied together, and there's this like extreme sense
of oneness with the universe, which is also quite sickening.
And then it's gone. And if I had been, you know,
(02:09):
sitting beside you in math class and I looked over
at you during one of these experiences, what would I see, Like,
what was your body doing, what was your face doing?
I mostly wouldn't show it. Sometimes I would like put
my head in my hands, and they're like, oh I
feel sick. I'd say to my friends all the time, like, oh,
I have deja vu. It's just the worst. And I
thought like maybe I was just really poorly adjusted to
(02:30):
it and everyone else could handle this much better. Okay,
So for years Anna is suffering from these debilitating episodes
of deja vu, and she assumes that's normal, Like, that's
just what being a person feels like. Deja vu is
French were already seen and most of us know. It
(02:52):
is the eerie feeling that you've lived this very moment already,
but usually it isn't so intense that it jettisons you
to the edge of I'm in space. If you're like me,
the standard response to deja vu is to start tugging
on your friend's sleeve to announce I have davu. Hey,
I need everyone here to acknowledge that I am deja
vuing right now. But it's a solitary experience. You can't
(03:16):
share it. You can't even articulate the moment without sounding
like a palm reader in a panic attack. I knew
you were going to say that deja vu doesn't happen
too often, which I think is why I sort of
like it. It's an exotic condition of mind, like getting
an egg with two yolks or something. It's also one
of the few occasions where you're acutely aware of your
(03:39):
own perception at work. It's like getting to taste your
own tongue, or that bit that David Foster Wallace does
about the fishes where the old fish asks the young
fish how's the water, and the young fish says, what
the hell is water? Are there any dumb jokes that
you have to endure? Like as soon as you tell
someone you're a day's researchers? Ever, like, however that before
(04:01):
all the time? That's and clearly she's a professor of
cognitive psychology or cogsi if you are both a snowboarder
and a PhD student. Years ago, and and her colleagues
designed a series of ambitious experiments. We were attempting to
induce stay Chevoo through virtual reality. How do you even
(04:21):
start to do that? I would spend hours and hours
playing the SIMS basically at my house on a laptop
in the lab. I'd close my eyes to go to sleep,
and I'd be dreaming about moving objects around within the
SIMS to create environments, because so Anne is building an
experimental laboratory inside the game, the sims when you create
(04:43):
the characters and design the surrounding the possibility got it,
That sims that weirdly successful video game, where you pretend
to be a person in a universe that's just like ours,
you can actually create entire neighborhoods. She builds an aquarium,
she builds a museum, She builds courtyards and residential structures.
(05:05):
She's on a construction spree, and although these spaces look different,
some of them are built on identical floor plans, with
major features in exactly the same places, Like a desk
is in exactly the same position is a bed is
in another scene. Let's say An sends a bunch of
people into this virtual neighborhood. She hands them a pair
(05:27):
of goggles, revs up the stems, and now her research
subjects can look all around the universe she's built, just
by turning their heads. She hypothesized that visiting places that
looked really different but had identical floor plans might induce
deja vu by triggering what's called a memory retrieval failure.
A memory retrieval failure is exactly what it sounds like
(05:50):
you've got a bit of info and storage, but you
can't fish it out for reference. It's like the search
function in my email. Sometimes it just can't find minutes
from Tuesday's meeting, even though they're in an email tie
minutes from Tuesday's meeting. So let's say you're all goggled
up in Anne's virtual world. If you visit the Bowling Alley,
you might get the sense, oh, this feels familiar, but
(06:12):
your recall might not pull up the fact that, uh,
this Bowling Alley is laid out just like the museum.
So you've got this inexplicable sense of having been here
before and bang deja vu and calls this digital universe,
wait for it, deja ville. This stuff about memory retrieval
(06:34):
failure is bigger than just deja vu. Sometimes it happens
in a really common phenomenon called the it's the um.
It's a feeling of being right on the verge of
accessing a word from memory. You feel pretty confident that
it's there, and it's it's right about to come to mind,
(06:54):
but it's not quite there yet. The tip of the
tongue thing, thank you, Anne, thank you. This is crazy
when you think about it like there's a memory I
can't access, but I know exactly where it is. It's
always almost here. Ant's work is based on this fallibility
of recall, the fact that our memories don't always come
when called. But there are other ways to understand deja vu.
(07:17):
And for all the time that an spends trying to
induce it, some people are desperately looking for help to
get out of it. I started my deja research while
I was in the memory clinic, and this man came
in to have his memory tested, and he had a
very unusual complaint because he said that he had already
been tested before, which was pretty strange because most people,
(07:38):
if they've been to a memory clinic before, they've tended
to forget about it. But he was complaining that he
had already done it before. That's Chris Moulin. He's a
researcher and a cognitive neuropsychologist, which means he studies the
structures of the brain to better understand how we think.
He's talking here about one of his seminal patients, a KP.
(07:58):
Taking a walk in the street. He would see the
same bird singing the same song in the same tree
every day, and he stopped watching the television because he
said he had seen it before. He stopped reading the
newspaper because he had already read it all. And his
wife was saying that, Yeah, this is typical of him.
He does this all the time. Chris's work with a
(08:20):
KP led him to other patients with similar symptoms. We
presented in the scientific literature a young man who had
a history of anxiety, some substance use, and he was
stuck in what he described as like a Donnie Darko
time loop. He was acutely aware, and he said he
had to really spend a long time reasoning with himself
(08:43):
that life wasn't repeating and that he wasn't going mad.
I remember driving four hours to meet with a patient
just had two emails with her daughter we've not met before,
and I turn up and she opens the door and
she greets me like she she knows me. Chris understands
(09:04):
deja vu to be caused by a glitch in the
memory system, where the feeling of recalling a memory becomes
disassociated from the act of actually doing it. According to Chris,
we can have the strong sensation of remembering something even
when there's no memory there like pushing a needle through
fabric feels like sewing, even if I've gotten no thread.
(09:27):
The glitch account of deja vu is very different from
the idea behind Anne's Deja Ville, where we've got a
memory we just can't retrieve. But I'm gonna tell you
right now, this is not a show where we picked
to deja vu scientists against each other to fight to
the death like post dot gladiators in the colosseum of
my podcast Let's keep It, Let's keep it classy for
(09:49):
the record, and thinks that some deja vu might be
caused by glitches too. Okay, a lot of the memory
patients that chris se'es are older, some suffering from the NHA.
Brain scans have revealed some subtle atrophy in particular regions
of their brains in the frontal lobes and the temporal
lobes at the side of the skull. So just to
(10:11):
get like the the anatomy right, you know, So if
I'm sitting right now with my my index finger against
the spot on my skull that's right above my right ear,
how deep would I sink that finger until I hit
the region that we're talking about, Like first knuckle, second knuckle, Okay,
(10:32):
so it would be your second knuckle. The memory center
is tucked into the very middle, so you're almost going
right into the center of the space between your ears.
But it's not like there's a discreete little memory cottage
in your brain. Apart from all the rest, there's a
complex set of interlocking parts, and understanding healthy memory function
(10:53):
could allow Chris and his colleagues to better serve people
who come looking for help who are really suffering. Chris
thinks deja vu might provide real insight into just how
this system works in normal circumstances during like regular vo
deja vu is just another one of the kind of
quirks of memory that helps us understand what the memory
(11:16):
system is. Not only is there kind of memory performance,
memory function, but there is also the relationship we have
with that memory. The beliefs about memory, the feelings about memory.
They're relatively automatic and they don't usually go wrong, but
when they go wrong, they are They are strange, striking experiences,
and the people who contact me are often in great distress.
(11:44):
My second year in college was the first time I
fully lost consciousness, and it happened like maybe two or
three times during college. Um, and I mean one time
was really scary because I had twisted my ankle while
walking down one step and the next thing I know, like,
I wake up on the ground. One of my friends
(12:07):
is standing over me, completely panicked. She said that my
eyes rolled into the back of my head and I
was shaking. It actually took until grad school for me
to realize truly that these things weren't just how some
people experienced deja voo. And I just remember talking to
my boyfriend about it because I had just lost consciousness
(12:28):
during class and it was very embarrassing, and I was saying, oh, yeah,
I get that feeling, you know with deja vu, where
you feel this kind of oneness and it's really sickening
and scary. And he was like, what he's got to
be like, I have no idea what you're talking about.
So maybe a couple of hours later, I pull out
(12:48):
my phone and I'm like, there's no way and the
only one who experiences this, you know, what did you Google?
I put in I think like nausea, deja vu and fainting,
clicked search and it was like epilepsy, epilepsy, brain tumors, epilepsy,
neurological disorders, and it's like, oh my god, I needed
(13:09):
to get an m r I in case I had
a brain tumor and needed to get an e G.
So it went from like zero to sixty on how
severe doctors perceived this as being for my e G.
I had to stay up all night. I guess your
(13:29):
brain is more prone to seizures or whatever disorders are
lurking there when you're low on sleep. I stayed up
all night watching The Fresh Prince of bel Air because
I love that show. Now, this is a story all
about how my life got swip turns upside down, and
I'd like to take so I did one of those,
and they saw some weird stuff going on in my
temporal lobe. Um. So, when I finally went to see
(13:53):
an actual neurologist and talked with her about it and
she was like, yeah, this is definitely temporal lobe epilepsy,
it it was like, that's good. That's good to just know.
In temporal lobe epilepsy, deja vu can actually be part
of the seizure, sometimes called an aura. For some people,
deja vu can serve as a storm warning that things
(14:15):
are about to get much much worse. Of course, deja
vu isn't always linked to epilepsy, but for a lot
of people, it is linked to feelings of precognition, the
ability to predict the future. We had hypothesized that maybe
people can, and maybe there's a scientific explanation for why.
And seriously, what are you talking about. If you've been
(14:38):
through a situation that's very much like the current situation,
maybe you do know exactly how it's going to unfold
because you've been through it before and you're just forgetting
or you've been through something very similar. And so we
had hypothesized that if we could somehow put people in
the middle of a memory, so to speak. So here
(15:00):
and changes her protocol this time when you put on
the goggles instead of turning your head and looking around
deja Ville. She's cued up several little videos, like virtual
tours that maneuver through the places she's built. Let's say
you enter the bowling Alley and then you go left,
and then you go right, when you hit the first
(15:20):
wall and you go left, and you go right one
more time, and subjects watch a bunch of these virtual
tours through all sorts of different places, and some tours
go through spaces with identical layouts following exactly the same route,
a fact that Anne hopes her subjects won't consciously realize,
(15:43):
but that might trigger deja vu. This bowling alley is
laid out just like the museum. And now here's the
moment of truth because Anne pauses one of these videos
in the middle of the route, right before it's about
to take a turn, and she asks her subjects if
they're feeling deja vu at the moment, and if so,
do they have that I can predict the future feeling?
(16:05):
Do you feel like you know the direction of the
next turn? And some people said, yes, I do have
deja vu? Yes, I do feel like I know what's
going to happen next. This tour is going left, man left,
let's unpause the thing and let's go left already. So
when an unpaused it, were they correct? We were really bombed. Actually,
(16:28):
the first time we ran the experiment, we found no
predictive ability at all. This poses a new question. If
people aren't actually able to foresee the future during deja vu,
why do they have such a strong impression that they
can well during a deja vu episode in regular life?
(16:49):
Like the action doesn't stop to allow us to test
our predictions. The tape just keeps running, so we're never
confronted by any evidence to disprove that overwhelm feeling of
I knew that would happen and thinks deja voo doesn't
allow us to make predictions. It's actually something called postdiction,
(17:11):
and it gives an illusion of having predicted after the
fact is there was some tension. You know, when you're
talking to somebody, there has to be who's like, yo,
I am clairvoyant and I have predicted the future, and
I bet they're not going to drop that easily. When
you're like, oh, actually, it just feels like you can
predict a few like that is not a satisfying response. No,
(17:32):
people people hate it. Um. I commonly hear from members
of the public that I'm wrong, that deja vu is
not a memory phenomenon. And when I started publishing work
on dejavoo being associated with illusory feelings of prediction, of course,
people started to push back at that to say, no,
(17:53):
when I feel like I can predict, I actually do predict,
and it's not just a feeling still and says it
is just a feeling. She sure because she tested for
exactly that. But anyone who's had it knows how real
DejaVu can feel. It descends like like a little private
tornado to lift you out of your everyday perceived continuum
(18:16):
of time and space. Do you ever get like the
pedestrian run of the mill version of dejava? I don't
think i'd recognize it, Like, I think I would just
dismiss it as so ordinary that I wouldn't even think
twice about, oh, this is real deja vu? Do you
(18:36):
think that you know this history of having profound and
unpleasant dejavue experiences shaped your personality in any way a
little bit? Um. I got really into philosophy when I
was a teenager, and I think that was pretty much
mostly due to these seizures that I had. I remember
(18:59):
reading different philosophers who talked about everyone experiences the world
very differently, and that rang true to me because I
was like, I think the way that other people experience
like deja vu is very different from me. The idea
that people experience consciousness differently, I think that fascinates a
lot of us. Like if I could test drive someone
(19:22):
else's mind trade consciousness is for a day, would it
feel disorienting like driving on the left, or would it
feel like trying to drive a baked potato or trying
to drive yellow? Could I even recognize it as a
mind and find all the pedals to make it go? Oh? Yeah?
Can I ask, like, what do you what do you
do for a living now? Oh? I'm a PhD student
(19:44):
of astrophysics. Okay, dang dude. Do you think that your
experiences of deja vu might feel like the experiences of
astronauts when they look at the world through the window
and it's just conceptualizes how how small a place in
(20:07):
the universe that they occupy. Yeah, that's a really great
way of thinking of it. I mean with astrophysics, it's
sort of like we are looking at the universe without us.
It's like seeing something outside of of how you normally
experience it, very far away. If you could rewrite your life,
(20:32):
would you write these deja vu experiences out of it? No?
I don't think so. These episodes felt like they cut
to the heart of existence. A lot of how I
understand the world comes from, like the way that I
sort of experienced time. In these seizures, you're you're seeing
(20:55):
the passage of time. We don't get to experience time directly,
don't have a dedicated sense organ for it, and I
think that's why even the occasional deja vu is sort
of thrilling, because it brings our sensation of time to
the four. We get a moment where we can really
(21:15):
feel it moving around us. Usually time is just the
invisible substrate that we maneuver through. We're like the fish
asking what's water, But of course I can see what's
in the bowl that holds the goldfish. Maybe on I
can see the bowl full of time that's holding me,
(21:42):
And that's deeply human on deja vu a sensation we
can experience in grade school, but takes a doctorate degree
to begin to explain. Our next stop on deeply Human
is a terminal. The topic is death and why it's
time to talk about yours. There's been lots of conversations
(22:03):
around this idea of a good death. I've never been
big on that terminology because then it suggests there's a
bad death. Once you start to create expectations around dying,
people can start to feel like they're doing it wrong.
And that's always been one of my big concerns with
a lot of the discussions around death and dying in
(22:24):
all different kinds of facets society, which has been going
on for like the last twenty years. It's never not
been a hot topic as it were. But I think
that what happens is families, and usually families more than
the dying, but sometimes the dying they can feel like
they're doing it wrong. Deeply Human is a co production
of the BBC World Service and American Public Media with
(22:47):
I Heart Media and it's spoken into a microphone by Medessa.
See you next question.
I'm Dessa, the disembodied lady voice of deeply human Why
we do the things we do? We're about to set
off on an episode of deja vu? Why do we
get it? And how could it help you better understand
the workings of your own mind. I I don't remember
the first time, but I remember when they started happening
(00:20):
really frequently. I would be in math class or something
and suddenly everything would feel kind of off, like I
don't know, if you know, this feeling in your gut
that something's just wrong. I think I was probably fourteen,
and I started getting them on maybe a daily basis
by the time I was sixteen, a daily basis. Mm hm,
(00:46):
can you describe, like, if I met you at fourteen,
what's your vibe? You know? Do you have like pink hair?
Do you have like thick glasses? What's the vibe? Um?
Just picture Avril Levine. It's a little bit cringe e
but a bit of a skater girl, you know. So
that means like dark eyeliner. Did your mama you wear eyeliner?
(01:07):
She did? Yeah, straightened hair, dark eyeliner, band, T shirt.
I start to feel kind of fearful and have the
sense of dread, and I start to feel really sick
to my stomach, and it starts building like there's there's
something that's going to take hold of me, and um,
(01:27):
I really don't want it to, so I try to
focus on what's going on around me, but it starts
invading my head more and more, and then it I
get to this point where it feels like everything that's
currently happening has already happened. And then it sort of
feels as though I can remember the history of the universe.
Of course I couldn't give any details of what that
(01:48):
even meant, but at the time, I like it, fully
convinced that that's what I'm feeling. I can remember everything
that's ever happened and everything that will ever happen, and
it's all tied together, and there's this like extreme sense
of oneness with the universe, which is also quite sickening.
And then it's gone. And if I had been, you know,
(02:09):
sitting beside you in math class and I looked over
at you during one of these experiences, what would I see, Like,
what was your body doing, what was your face doing?
I mostly wouldn't show it. Sometimes I would like put
my head in my hands, and they're like, oh I
feel sick. I'd say to my friends all the time, like, oh,
I have deja vu. It's just the worst. And I
thought like maybe I was just really poorly adjusted to
(02:30):
it and everyone else could handle this much better. Okay,
So for years Anna is suffering from these debilitating episodes
of deja vu, and she assumes that's normal, Like, that's
just what being a person feels like. Deja vu is
French were already seen and most of us know. It
(02:52):
is the eerie feeling that you've lived this very moment already,
but usually it isn't so intense that it jettisons you
to the edge of I'm in space. If you're like me,
the standard response to deja vu is to start tugging
on your friend's sleeve to announce I have davu. Hey,
I need everyone here to acknowledge that I am deja
vuing right now. But it's a solitary experience. You can't
(03:16):
share it. You can't even articulate the moment without sounding
like a palm reader in a panic attack. I knew
you were going to say that deja vu doesn't happen
too often, which I think is why I sort of
like it. It's an exotic condition of mind, like getting
an egg with two yolks or something. It's also one
of the few occasions where you're acutely aware of your
(03:39):
own perception at work. It's like getting to taste your
own tongue, or that bit that David Foster Wallace does
about the fishes where the old fish asks the young
fish how's the water, and the young fish says, what
the hell is water? Are there any dumb jokes that
you have to endure? Like as soon as you tell
someone you're a day's researchers? Ever, like, however that before
(04:01):
all the time? That's and clearly she's a professor of
cognitive psychology or cogsi if you are both a snowboarder
and a PhD student. Years ago, and and her colleagues
designed a series of ambitious experiments. We were attempting to
induce stay Chevoo through virtual reality. How do you even
(04:21):
start to do that? I would spend hours and hours
playing the SIMS basically at my house on a laptop
in the lab. I'd close my eyes to go to sleep,
and I'd be dreaming about moving objects around within the
SIMS to create environments, because so Anne is building an
experimental laboratory inside the game, the sims when you create
(04:43):
the characters and design the surrounding the possibility got it,
That sims that weirdly successful video game, where you pretend
to be a person in a universe that's just like ours,
you can actually create entire neighborhoods. She builds an aquarium,
she builds a museum, She builds courtyards and residential structures.
(05:05):
She's on a construction spree, and although these spaces look different,
some of them are built on identical floor plans, with
major features in exactly the same places, Like a desk
is in exactly the same position is a bed is
in another scene. Let's say An sends a bunch of
people into this virtual neighborhood. She hands them a pair
(05:27):
of goggles, revs up the stems, and now her research
subjects can look all around the universe she's built, just
by turning their heads. She hypothesized that visiting places that
looked really different but had identical floor plans might induce
deja vu by triggering what's called a memory retrieval failure.
A memory retrieval failure is exactly what it sounds like
(05:50):
you've got a bit of info and storage, but you
can't fish it out for reference. It's like the search
function in my email. Sometimes it just can't find minutes
from Tuesday's meeting, even though they're in an email tie
minutes from Tuesday's meeting. So let's say you're all goggled
up in Anne's virtual world. If you visit the Bowling Alley,
you might get the sense, oh, this feels familiar, but
(06:12):
your recall might not pull up the fact that, uh,
this Bowling Alley is laid out just like the museum.
So you've got this inexplicable sense of having been here
before and bang deja vu and calls this digital universe,
wait for it, deja ville. This stuff about memory retrieval
(06:34):
failure is bigger than just deja vu. Sometimes it happens
in a really common phenomenon called the it's the um.
It's a feeling of being right on the verge of
accessing a word from memory. You feel pretty confident that
it's there, and it's it's right about to come to mind,
(06:54):
but it's not quite there yet. The tip of the
tongue thing, thank you, Anne, thank you. This is crazy
when you think about it like there's a memory I
can't access, but I know exactly where it is. It's
always almost here. Ant's work is based on this fallibility
of recall, the fact that our memories don't always come
when called. But there are other ways to understand deja vu.
(07:17):
And for all the time that an spends trying to
induce it, some people are desperately looking for help to
get out of it. I started my deja research while
I was in the memory clinic, and this man came
in to have his memory tested, and he had a
very unusual complaint because he said that he had already
been tested before, which was pretty strange because most people,
(07:38):
if they've been to a memory clinic before, they've tended
to forget about it. But he was complaining that he
had already done it before. That's Chris Moulin. He's a
researcher and a cognitive neuropsychologist, which means he studies the
structures of the brain to better understand how we think.
He's talking here about one of his seminal patients, a KP.
(07:58):
Taking a walk in the street. He would see the
same bird singing the same song in the same tree
every day, and he stopped watching the television because he
said he had seen it before. He stopped reading the
newspaper because he had already read it all. And his
wife was saying that, Yeah, this is typical of him.
He does this all the time. Chris's work with a
(08:20):
KP led him to other patients with similar symptoms. We
presented in the scientific literature a young man who had
a history of anxiety, some substance use, and he was
stuck in what he described as like a Donnie Darko
time loop. He was acutely aware, and he said he
had to really spend a long time reasoning with himself
(08:43):
that life wasn't repeating and that he wasn't going mad.
I remember driving four hours to meet with a patient
just had two emails with her daughter we've not met before,
and I turn up and she opens the door and
she greets me like she she knows me. Chris understands
(09:04):
deja vu to be caused by a glitch in the
memory system, where the feeling of recalling a memory becomes
disassociated from the act of actually doing it. According to Chris,
we can have the strong sensation of remembering something even
when there's no memory there like pushing a needle through
fabric feels like sewing, even if I've gotten no thread.
(09:27):
The glitch account of deja vu is very different from
the idea behind Anne's Deja Ville, where we've got a
memory we just can't retrieve. But I'm gonna tell you
right now, this is not a show where we picked
to deja vu scientists against each other to fight to
the death like post dot gladiators in the colosseum of
my podcast Let's keep It, Let's keep it classy for
(09:49):
the record, and thinks that some deja vu might be
caused by glitches too. Okay, a lot of the memory
patients that chris se'es are older, some suffering from the NHA.
Brain scans have revealed some subtle atrophy in particular regions
of their brains in the frontal lobes and the temporal
lobes at the side of the skull. So just to
(10:11):
get like the the anatomy right, you know, So if
I'm sitting right now with my my index finger against
the spot on my skull that's right above my right ear,
how deep would I sink that finger until I hit
the region that we're talking about, Like first knuckle, second knuckle, Okay,
(10:32):
so it would be your second knuckle. The memory center
is tucked into the very middle, so you're almost going
right into the center of the space between your ears.
But it's not like there's a discreete little memory cottage
in your brain. Apart from all the rest, there's a
complex set of interlocking parts, and understanding healthy memory function
(10:53):
could allow Chris and his colleagues to better serve people
who come looking for help who are really suffering. Chris
thinks deja vu might provide real insight into just how
this system works in normal circumstances during like regular vo
deja vu is just another one of the kind of
quirks of memory that helps us understand what the memory
(11:16):
system is. Not only is there kind of memory performance,
memory function, but there is also the relationship we have
with that memory. The beliefs about memory, the feelings about memory.
They're relatively automatic and they don't usually go wrong, but
when they go wrong, they are They are strange, striking experiences,
and the people who contact me are often in great distress.
(11:44):
My second year in college was the first time I
fully lost consciousness, and it happened like maybe two or
three times during college. Um, and I mean one time
was really scary because I had twisted my ankle while
walking down one step and the next thing I know, like,
I wake up on the ground. One of my friends
(12:07):
is standing over me, completely panicked. She said that my
eyes rolled into the back of my head and I
was shaking. It actually took until grad school for me
to realize truly that these things weren't just how some
people experienced deja voo. And I just remember talking to
my boyfriend about it because I had just lost consciousness
(12:28):
during class and it was very embarrassing, and I was saying, oh, yeah,
I get that feeling, you know with deja vu, where
you feel this kind of oneness and it's really sickening
and scary. And he was like, what he's got to
be like, I have no idea what you're talking about.
So maybe a couple of hours later, I pull out
(12:48):
my phone and I'm like, there's no way and the
only one who experiences this, you know, what did you Google?
I put in I think like nausea, deja vu and fainting,
clicked search and it was like epilepsy, epilepsy, brain tumors, epilepsy,
neurological disorders, and it's like, oh my god, I needed
(13:09):
to get an m r I in case I had
a brain tumor and needed to get an e G.
So it went from like zero to sixty on how
severe doctors perceived this as being for my e G.
I had to stay up all night. I guess your
(13:29):
brain is more prone to seizures or whatever disorders are
lurking there when you're low on sleep. I stayed up
all night watching The Fresh Prince of bel Air because
I love that show. Now, this is a story all
about how my life got swip turns upside down, and
I'd like to take so I did one of those,
and they saw some weird stuff going on in my
temporal lobe. Um. So, when I finally went to see
(13:53):
an actual neurologist and talked with her about it and
she was like, yeah, this is definitely temporal lobe epilepsy,
it it was like, that's good. That's good to just know.
In temporal lobe epilepsy, deja vu can actually be part
of the seizure, sometimes called an aura. For some people,
deja vu can serve as a storm warning that things
(14:15):
are about to get much much worse. Of course, deja
vu isn't always linked to epilepsy, but for a lot
of people, it is linked to feelings of precognition, the
ability to predict the future. We had hypothesized that maybe
people can, and maybe there's a scientific explanation for why.
And seriously, what are you talking about. If you've been
(14:38):
through a situation that's very much like the current situation,
maybe you do know exactly how it's going to unfold
because you've been through it before and you're just forgetting
or you've been through something very similar. And so we
had hypothesized that if we could somehow put people in
the middle of a memory, so to speak. So here
(15:00):
and changes her protocol this time when you put on
the goggles instead of turning your head and looking around
deja Ville. She's cued up several little videos, like virtual
tours that maneuver through the places she's built. Let's say
you enter the bowling Alley and then you go left,
and then you go right, when you hit the first
(15:20):
wall and you go left, and you go right one
more time, and subjects watch a bunch of these virtual
tours through all sorts of different places, and some tours
go through spaces with identical layouts following exactly the same route,
a fact that Anne hopes her subjects won't consciously realize,
(15:43):
but that might trigger deja vu. This bowling alley is
laid out just like the museum. And now here's the
moment of truth because Anne pauses one of these videos
in the middle of the route, right before it's about
to take a turn, and she asks her subjects if
they're feeling deja vu at the moment, and if so,
do they have that I can predict the future feeling?
(16:05):
Do you feel like you know the direction of the
next turn? And some people said, yes, I do have
deja vu? Yes, I do feel like I know what's
going to happen next. This tour is going left, man left,
let's unpause the thing and let's go left already. So
when an unpaused it, were they correct? We were really bombed. Actually,
(16:28):
the first time we ran the experiment, we found no
predictive ability at all. This poses a new question. If
people aren't actually able to foresee the future during deja vu,
why do they have such a strong impression that they
can well during a deja vu episode in regular life?
(16:49):
Like the action doesn't stop to allow us to test
our predictions. The tape just keeps running, so we're never
confronted by any evidence to disprove that overwhelm feeling of
I knew that would happen and thinks deja voo doesn't
allow us to make predictions. It's actually something called postdiction,
(17:11):
and it gives an illusion of having predicted after the
fact is there was some tension. You know, when you're
talking to somebody, there has to be who's like, yo,
I am clairvoyant and I have predicted the future, and
I bet they're not going to drop that easily. When
you're like, oh, actually, it just feels like you can
predict a few like that is not a satisfying response. No,
(17:32):
people people hate it. Um. I commonly hear from members
of the public that I'm wrong, that deja vu is
not a memory phenomenon. And when I started publishing work
on dejavoo being associated with illusory feelings of prediction, of course,
people started to push back at that to say, no,
(17:53):
when I feel like I can predict, I actually do predict,
and it's not just a feeling still and says it
is just a feeling. She sure because she tested for
exactly that. But anyone who's had it knows how real
DejaVu can feel. It descends like like a little private
tornado to lift you out of your everyday perceived continuum
(18:16):
of time and space. Do you ever get like the
pedestrian run of the mill version of dejava? I don't
think i'd recognize it, Like, I think I would just
dismiss it as so ordinary that I wouldn't even think
twice about, oh, this is real deja vu? Do you
(18:36):
think that you know this history of having profound and
unpleasant dejavue experiences shaped your personality in any way a
little bit? Um. I got really into philosophy when I
was a teenager, and I think that was pretty much
mostly due to these seizures that I had. I remember
(18:59):
reading different philosophers who talked about everyone experiences the world
very differently, and that rang true to me because I
was like, I think the way that other people experience
like deja vu is very different from me. The idea
that people experience consciousness differently, I think that fascinates a
lot of us. Like if I could test drive someone
(19:22):
else's mind trade consciousness is for a day, would it
feel disorienting like driving on the left, or would it
feel like trying to drive a baked potato or trying
to drive yellow? Could I even recognize it as a
mind and find all the pedals to make it go? Oh? Yeah?
Can I ask, like, what do you what do you
do for a living now? Oh? I'm a PhD student
(19:44):
of astrophysics. Okay, dang dude. Do you think that your
experiences of deja vu might feel like the experiences of
astronauts when they look at the world through the window
and it's just conceptualizes how how small a place in
(20:07):
the universe that they occupy. Yeah, that's a really great
way of thinking of it. I mean with astrophysics, it's
sort of like we are looking at the universe without us.
It's like seeing something outside of of how you normally
experience it, very far away. If you could rewrite your life,
(20:32):
would you write these deja vu experiences out of it? No?
I don't think so. These episodes felt like they cut
to the heart of existence. A lot of how I
understand the world comes from, like the way that I
sort of experienced time. In these seizures, you're you're seeing
(20:55):
the passage of time. We don't get to experience time directly,
don't have a dedicated sense organ for it, and I
think that's why even the occasional deja vu is sort
of thrilling, because it brings our sensation of time to
the four. We get a moment where we can really
(21:15):
feel it moving around us. Usually time is just the
invisible substrate that we maneuver through. We're like the fish
asking what's water, But of course I can see what's
in the bowl that holds the goldfish. Maybe on I
can see the bowl full of time that's holding me,
(21:42):
And that's deeply human on deja vu a sensation we
can experience in grade school, but takes a doctorate degree
to begin to explain. Our next stop on deeply Human
is a terminal. The topic is death and why it's
time to talk about yours. There's been lots of conversations
(22:03):
around this idea of a good death. I've never been
big on that terminology because then it suggests there's a
bad death. Once you start to create expectations around dying,
people can start to feel like they're doing it wrong.
And that's always been one of my big concerns with
a lot of the discussions around death and dying in
(22:24):
all different kinds of facets society, which has been going
on for like the last twenty years. It's never not
been a hot topic as it were. But I think
that what happens is families, and usually families more than
the dying, but sometimes the dying they can feel like
they're doing it wrong. Deeply Human is a co production
of the BBC World Service and American Public Media with
(22:47):
I Heart Media and it's spoken into a microphone by Medessa.
See you next question.
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