Kind: captions
Language: en
the act of remembering can change the
memory if you remember some event and
then I tell you something about the
event later on when you remember the
event you might remember some original
information from the event as well as
some information about what I told you
and sometimes if you're not able to tell
the difference that information that I
told you gets mixed into the story that
you had originally so now I give you
some more misinformation or you're
exposed to some more information some
else and eventually your memory becomes
totally detached from what
happened the following is a conversation
with Chon ranganath a psychologist and
neuroscientist at UC Davis specializing
in human memory he's the author of why
we remember unlocking memory's power to
hold on to what
matters this is the Lex Freedman podcast
to support it please check out our
sponsors in the description and now dear
friends here's Chon
rangano Danny Conan describes the
experiencing self and the remembering
self and that happiness and satisfaction
you gained from the outcomes of your
decisions did not come from what you've
experienced but rather from what you
remember of the experience so uh can you
speak to this interesting difference
that you write about in your book of the
experiencing self and the remembering
self Danny really impacted me cuz I was
an undergrad at Berkeley and I got to
take a class from him long before he won
the Nobel Prize or anything and it was
just a mind-blowing class but this idea
of the remembering self and the
experiencing self I got into it because
it's so much about memory even though he
doesn't study memory so we're right now
having this experience right and people
are can watch it presumably on YouTube
or listen to it on audio but if you're
talking to somebody else you could
probably describe this whole thing in 10
minutes but that's going to miss a lot
of what actually happened and so the
idea there is is that the way we
remember things is not the replay of the
experience it's something totally
different and it tends to be biased by
the beginning and the end and he talks
about the Peaks but there's also the you
know the best parts the worst Parts Etc
and those are the things that we
remember and so when we make decisions
we usually consult memory and we feel
like our memories are record of what
we've experienced but it's not it's this
kind of very biased sample but it's
biased in an interesting and I think
biologically relevant way so in the way
we construct a narrative about our
past you say that uh it gives us an
illusion of stability can you explain
that basically I think that a lot of
learning in the brain is driven towards
being able to make sense I mean really
memory is all about the the present and
the Future Past is done so biologically
speaking it's not important unless
there's something from the past that's
useful and so what our brains are really
optimized for is to learn about the
stuff from the past that's going to be
most useful in understanding the present
and predicting the future right and so
cause effect relationships for instance
that's a big one now my future is
completely unpredictable in the sense
that like you could you know in the next
10 minutes pulling KN on me and slipped
my throat right I was planning on it ex
but having seen some of your work and
just you know generally my expectations
about life I'm not expecting that I have
a certainty that everything's going to
be fine we're going to have a great time
talking today right but we're often
right it's like okay so I go to a a see
a band on stage you know I know they're
going to make me wait the show's going
to start late and then you know come
they come on there's a very good chance
there's going to be an encore I have a
memory so to speak for that event before
I've even walked into the show right
there's going to be people holding up
their camera phones to try to take
videos of it now because this is kind of
the world we live in so that's like
everyday fortune telling that we do
though it's not real it's imagine and
it's amazing that we have this
capability and that's what memory is
about uh but it can also give us this
illusion that we know everything that's
about to happen um and I think what's
valuable about that that illusion is
when it's broken it gives us the
information right so I mean I'm sure
being in AI you know about information
Theory and the idea is the information
is what you didn't already have and so
those prediction errors that we make
based on you know we make a prediction
based on memory and the errors are where
the action is the error is where the
Learning Happens exactly
exactly well just to linger on Danny
Conan and just this whole idea
of experiencing self versus remembering
self I was hoping you can give a simple
answer of how we should live life uh
based on the fact that our memories
could be a source of happiness or could
be the primary source of happiness that
an event when experienced Bears its
fruits the most when it's remembered
over and over and over and over and
maybe there is some wisdom in the fact
that we can control to some degree how
we remember it how we evolve our memory
of it such that it can
maximize the long-term happiness of that
repeated experience okay well first I'll
say I wish I could take you on the road
with me that was such a great
description can I be your opening act or
oh my God no I'm going to open for you
dude otherwise it's like you know
everybody leaves after you're done
believe me I did that in in Columbus
Ohio once it wasn't fun like the opening
acts like drank our bab we spent all
this money going all the way there there
was only the everybody left after the
opening acts were done and there was
just that Stoner dude with the
dreadlocks hanging out and then next you
know we we blew like our savings on
getting a hotel room so we should as a
small tangent you're a legit touring act
when I was in grad school I played in a
band and yeah we traveled we would play
shows it wasn't like we were in a
hardcore touring band but we did some
touring and and had some fun times and
yeah you did we did a movie soundtrack
nice Henry portrait of serial killer so
that's a good movie we were on the
soundtrack for the sequel Henry 2 mask
of Sanity which is a terrible movie yeah
how's the soundtrack it's pretty good
it's badass at least that one part where
the guy throws up the milkshake all
right song we're going to have to see
we're going to have to see it all right
we're getting back to life advice you
know yeah uh one thing that I try to
live by especially nowadays and since I
wrote the book I've been thinking more
and more about this is how do I want to
live a memorable life you know I think
if we go back to like the pandemic right
how many people have memories from that
period aside from the trauma of being
you know locked up and seeing people die
and all the stuff um I think it's like
one of these things where we were stuck
inside looking at screens all day doing
the same thing with the same people and
so I don't remember much from that in
terms of those good memories that you're
talking about right you know when I was
growing up my parents worked really hard
for us and you know we went on some
vacations but not very often and I
really try to do now vacations to
interesting places as much as possible
with my family because like those are
the things that you remember right so I
I really do think about what's going to
be like something that's memorable and
then just do it even if it's a pain in
the ass because the experiencing self
will suffer for that but the remembering
self will be like yes I'm so glad I did
that do things that are very unpleasant
in the moment because those can be
reframed and enjoyed for many years to
come that's
probably um good advice or at least when
you're going through it's a good
way to uh see the silver lining of it
yeah I mean I think it's one of these
things where if you have like people who
you've gone through I since you said it
I'll just say since you've gone through
with someone and it's like uh
that's a bonding experience often you
know I mean that can really bring you
together I like to say it's like there's
no point in suffering unless you get a
story out of it so uh in the book I talk
about the power of the way we
communicate with others and how that
shapes our memories and so I had this
near-death experience at least that's
how I remember it on this paddle board
where just everything that could have
gone wrong did go wrong almost um so
many mistakes were made and um um ended
up like at some point just like
basically away from my board pinned in a
current like in this corner like not a
super good swimmer and my friend who
came with me Randy who's a computational
neuroscientist and he had just been
pushed down uh past me so he couldn't
even see me and I'm just like if I die
here you know I mean no one's around
it's it's like you just die alone and so
I just said well failure is not an
option and eventually I got out of it
and uh froze and got cut up and I mean
the the things that we were going
through were just insane but short
version of this is uh you know my my
wife and my daughter and ry's wife they
gave us all sorts of Hell about this cuz
they were just like where they were
ready to send out a search party so they
were giving me hell about it and then I
started to tell people in my lab about
this and then friends and it just became
a better and better story every time and
we actually had some photos of just the
crazy things like this generator that
was hanging over the water and we're
like ducking under this Z these metal
grings and I'm like going flat on and I
was just nuts you know but it became a
great story and it was defin I mean
Randy and I were already tight but that
was a real bonding experience for us and
yeah I mean and I learned from that that
it's like I don't look back on that
enough actually because I think uh we
often H at least for me I don't
necessarily have the confidence to think
that things will work out that I'll be
able to get through certain thing but my
ability to to actually get something
done in that moment is better than I
give myself credit for I think and uh
that was the lesson of that story that I
really took away well actually just for
me you're making me realize now that
it's not just those kinds of stories but
even things like periods of depression
or really low points to me at least it
feels like um motivating thing that the
darker it gets the better the story will
be if you emerge on the other side that
to me feel feels like a motivating thing
so maybe if people listening to this and
they're going through some as we
said uh one one thing um that could be a
source of light is that it'll be a hell
of a good story when it's all over when
you merge in the other
side uh let me ask you about decisions
you've you already talked about it a
little bit but when we Face the world
and we're making different
decisions how much does our
memory come into play is it the the kind
of narratives that we've constructed
about the world that are used to make
predictions that's fundamentally part of
the decision- making absolutely yeah so
let's say after this you and I decided
we're going to go for a beer right how
do you choose where to go you're
probably going to be like oh yeah this
new bar opened up near me had a great
time there they had a great beer
selection or you might say oh we went to
this place and it was totally crowded
and they're playing this horrible EDM or
whatever and so right there valuable
source of information right and then you
have these things like where you do this
counterfactual stuff like well well I
did this previously but what if I had
gone somewhere else and said maybe I'll
go to this other place because I didn't
try it the previous time so there's all
that kind of reasoning that goes into it
too um I think even if you think about
the big decisions in life right it's
like you and I were talking before we
started recording about how I got into
memory research and you got into uh Ai
and it's like we all have these personal
reasons that guide us in these
particular directions and some of it's
the and environment and random factors
in life and some of it is memories of
things that we want to overcome or
things that we build on in a positive
way but either way they Define us and
probably the earlier in life the
memories happen the more defining the
more defining power they have in terms
of determining who we become I mean I do
feel like adolesence is much more
important than I think people give
credit for I think that there is this
kind of a sense like you know um the
first three years of life is the most
important part but uh the teenage years
are just so important for the brain you
know and so that's where a lot of mental
illness starts to emerge um you know now
we're thinking of things like
schizophrenia as a neurodevelopmental
disorder because it just emerges during
that period of adolescence and early
adulthood so and I think the other part
of it is is that you know as I guess I
was a little bit too firm in saying that
memory determines who we are it's really
the self is an evolving construct I
think we kind of underestimate that and
when you're a parent you feel like every
decision you make is consequential in
forming this child and plays a role but
so do the child's peers and so do you
know there's so much I mean that's why I
think the big part of Education I think
that's so important is not the content
you learn I mean think of how much dumb
stuff we learned in school right but uh
a lot of it is learning how to get along
with people and learning who you are and
how you function and you know that can
be terribly traumatizing even if you
have a perfect you know parents working
on you is there some insight into the
human brain that explains um why we
don't seem to remember anything from the
first few years of life yeah yeah in
fact actually I was just talking to my
uh really good friend and colleague
Simona gy who studies uh the
Neuroscience of Child Development and so
we were talking about this and so there
are a bunch of reasons I would say so
one reason is there's an area of the
brain in the called the hippocampus
which is very very important for
remembering events or episodic memory
and so the first two years of life
there's a period called infantile
Amnesia and then the next couple years
of life after that there's a period
called childhood Amnesia and the
difference is that basically in lab and
you know even during childhood and
afterwards children basically don't have
any episodic memories for those first
two years the next two years it's very
fragmentary and that's why they call it
childhood Amnesia so there's some but
it's not much so one reason is that the
hippocampus is taking some time to
develop but another is the neocortex so
the whole folded stuff of gray matter
all around the hippocampus is developing
so rapidly and changing
and a child's knowledge of the world is
just massively being built up right so I
mean I'm going to probably embarrass
myself but it's like if you showed like
you know you trained a neural network
and you give it like the first couple of
patterns or something like that and then
you bombard it with another like you
know years worth of data try to get back
those first couple of patterns right
it's like everything changes and so the
brain is so plastic the cortex is so
plastic during that time and we think
that that memories for events are very
distributed across the brain so imagine
you're trying to get back that pattern
of activity that happened during this
one moment but the roads that you would
take to get there have been completely
rerouted right so I think that's my best
explanation the third explanation is a
child's sense of self takes a while to
develop and so their experience of
learning might be more learning what
happened as opposed to having this first
person experience of I remember was
there well I think somebody uh once said
to me that uh kind of loosely
philosophically that the reason we don't
remember the first few years of life
infantile Amnesia is because how
traumatic it is MH basically the the
error rate that you mentioned when your
brain's prediction doesn't match reality
the error rate in the first few years of
life your first few months certainly is
probably crazy high it's just nonstop
freaking out the the collision between
your model of the world and how the
world works is just so high that you
want whatever the trauma of that is not
to linger around I always thought that
an interesting idea because like just
imagine the insanity of what's happening
in a human brain in the first couple
years just you you don't know anything
and there's just this stream of
knowledge and we're somehow
given how plastic everything is he just
kind of molds and figures it out but
it's it's like an
insane waterfall of information I
wouldn't necessarily describe it as a
trauma and we can get into this whole
stages of Life thing which I just love
basically those first few years there
are I mean you know I mean think about
it a kid's internal model of their body
is changing right it's like just
learning to move I mean like you know
you if you ever have a baby you'll know
that like the first three months they're
discovering their toes right it's just
nuts so everything is changing but
what's really fascinating is and I think
this is one of those this is not at all
me being a scientist but it's like one
of those things that people talk about
when they talk about the you know
positive aspects of children is that
they're exceptionally curious and they
have this kind of openness towards the
world and so that prediction error is
not a a negative traumatic thing I think
it's like a very positive thing because
it's what they use they're seeking
information one of the areas that I'm
very interested in is the prefrontal
cortex it's an area of the brain that I
mean I could talk all day about it but
it's it helps us use our knowledge to
say hey this is what I want to do now
this is my goal so this is how I'm going
to achieve it and focus everything
toward cycle right the prefrontal cortex
takes forever to develop in humans the
connections are still being tweaked and
reformed like into late adolescence
early adulthood which is when you tend
to see mental illness pop up right so
it's being massively reformed then you
have about 10 years maybe of prime
functioning of the prefrontal cortex and
then it starts going down again and you
end up being older and you start losing
all that frontal function so look at
this and you'd say okay from you sit
around episodic memory talks we always
say children are worse than adults at
episodic memory
older adults or worse than young adults
at episodic memory and I always say
would say God this so weird why would we
have this period of time that's so short
when we're perfect right or optimal and
I I like to use the word optimal now
because there's such a culture of
optimization right now and it's like I
realize I have to redefine what optimal
is because for most of the Human
Condition I think we had a series of
stages of life where you have
basically adults saying okay young
adults saying I've got a child and you
know I'm part of this Village and I have
to hunt and forage and get things done I
need a prefrontal cortex so I can stay
focused on the big picture and the Long
Haul goals now I'm a child I'm in this
Village I'm kind of wandering around and
I've got some safety and I need to learn
about this culture because I know so
little what's the best way to do that
let's explore I don't want to be
constrained by goals as much I want to
really be free play and explore and
learn so you don't want a super tight
prefrontal cortex you don't even know
what the goals should be yet right it's
like if you're trying to design a model
that's based on a bad goal it's G to
it's not going to work well right so
then you go late in life you say why
don't you have a great prefrontal cortex
then but I think I mean if you go back
and you think how many species actually
stick around naturally long after their
child bearing ears are over after the
reproductive years are over like
menopause from what I understand
menopause is not all that common in the
animal world right why would that happen
and so I saw Alison gnik said something
about this so I started to look into
this about this idea that you know
really when you're older in most
societies your job is no longer to form
new episodic memories it's to pass on
the memories that you already have this
knowledge about the world or what we
call semantic meor memory to pass on
that semantic memory to the younger
Generations pass on the culture you know
even now in indigenous cultures that's
the role of the elders they're respected
they're not seen as you know people who
are past it and losing it and I thought
that was a very poignant thing that
memory is doing what it's supposed to
throughout these stages of life so it is
always optimal in a sense it's just
optimal for that stage of Life yeah and
for the Ecology of the system so you've
got so I looked into this and it's like
another species that has menopause is
Orcas Orca pods are led by the
grandmothers right so not the young
adults not the parents or whatever the
grandmothers and so they're the ones
that pass on the Traditions to the I
guess the younger generation of orcas
and if you you know if you look from
what little I understand different Orca
pods have different Traditions they hunt
for different things they have different
play traditions and uh that's a culture
right and so in Social
animals Evolution I think is designing
brains that are really around you know
it's it's obviously optimized for the
individual but also for kin and I think
that the kin are part of this like when
they're part of this intense social
group The Brain development should
parallel that the nature of the ecology
well it's just fascinating to think of
the individual Orca or human throughout
his life in stages doing a kind of
optimal wisdom development so in the
early days you don't even know what the
goal is and you figure out the goal and
you kind of optimize for that goal and
you pursue that goal and then all the
wisdom you collect through that then you
share with the others in the system with
the other individuals and as a as a
collective then you kind of converge
towards greater wisdom throughout the
generation so in that sense it's optimal
us humans and orcas got something going
on it works yeah apex
predators uh I just got a meglan on
tooth speaking of a Apex parties it's uh
just imagine the size of that
thing anyway uh how does the brain
forget and how and why does it remember
so maybe some of the mechanisms you
mentioned the hippocampus what are the
different components involved here so we
can think about this on a number of
levels maybe I'll give you the simplest
version first which is we tend to think
of memories as these individual things
and we can just access them maybe a
little bit like you know photos on your
phone or something like that but in the
brain the way it works is you have this
distributed pool of neurons and the
memories are kind of shared across
different pools of neurons and so what
you have is competition where sometimes
memories that overlap can be fighting
against each other right so sometimes we
forget because that competition just
wipes things out sometimes we forget
because there aren't the biological
signals which we can get into that would
promote long-term retention and lots of
times we forget because we can't find
the queue that sends us back to the
right memory and we need the right cue
to be able to activate it right so um
you know for instance in an neural
network there is no you wouldn't go and
you'd say this is the memory right it's
like the whole Network I mean the whole
ecosystem of memories is in the weights
of the neural network and in fact you
could extract entirely new memories
depending on how you feed yeah you have
to have the right query the right prompt
to access that whatever the part you're
looking for that's exactly right that's
exactly right and in humans you have
this more complex set of ways memory
works there's as I said the knowledge or
what you call semantic memory and then
there's these memories for specific
events which we call episodic memory and
so there's different pieces of the
puzzle that require different kinds of
cues so that's a big part of it too is
just this kind of what we call retrieval
failure you mentioned episodic memory
you mentioned semantic memory what are
the different separations here what's uh
working memory short-term memory
long-term memory what are the
interesting categories of memory yeah
and so memory researchers we love to cut
things up and say you know is memory one
thing or is it two things there's two
things or is three things and so one of
the things that there's value in that
and especially experimental value in
terms of being able to dissect thing in
the real world it's all connected speak
to your question working memory is a
term that was coined by Alan battley
it's basically thought to be this
ability to keep information online in
your mind right in front of you at a
given time and to be able to control the
flow of that information to choose what
information is relevant to be able to
manipulate it and so forth and one of
the things that Allan did that was was
quite brilliant was he said there's this
ability to kind of passively store
information you know see things in your
mind's eye or hear your internal
monologue but um you know we have that
ability to keep information in mind but
then we also have the separate what you
called an a central executive which is
identified a lot with the prefrontal
cortex it's this ability to control the
flow of information that's being kept
active based on what it is you're doing
now a lot of my early work was basically
saying that this working memory which
some memory researchers would call
short-term memory is not at all
independent from long-term memory that
is that a lot of executive function
requires learning and you have to have
like synaptic change for that to happen
and um but there's also transient forms
of memory so one of the things I've been
getting into lately is the idea that we
form internal models of events the
obvious one that I always us as birthday
parties right so you go to a child's
birthday party once the cake comes out
and they start you just see a candle You
can predict the whole frame you know set
of events that happens later and up till
that point where the child blows out the
candle you have an internal model in
your head of what's going on and so if
you follow people's eyes it's not
actually on what's happening it's going
where the action's about to happen um
which is just fascinating right so you
have this internal model and that's a
kind of a working memory product it's
something that you're keeping online
that's allowing you to interpret this
world around you now to build that model
though you need to pull out stuff from
uh your general knowledge of the world
which is what we call semantic memory
and then you'd want to be able to pull
out memories for specific events that
happen in the past which we call
episodic memory so in a way they're all
connected even though it's different um
the things that we're focusing on and
the way we organize information in the
present which is working memory will
play a big role in determining how we
remember that information later which
people typically call long-term memory
so if you have something like a a
birthday party and you've been to many
before you're going to load that from
dis into working memory this model and
then you're mostly operating on the
model and if it's a
new task you're you don't have a model
so you're more in the data collection
yeah one of the fascinating things that
we've been studying and this is we're
not at all the first to do this Jeff ZX
was a big Pioneer in this um and I've
been working with many other people Ken
Norman um Lea daachi NY or Colombia has
done some interesting stuff with this is
this idea that we form these internal
models at particular points of high
prediction error or points of I believe
also points of uncertainty points of
surprise or motivationally significant
periods and those points are when it's
maximally op optimal to encode an
episodic memory so I used to think oh
well we're just encoding episodic
memories constantly boom boom boom boom
boom but think about how much redundancy
there is in all that right it's just a
lot of information that you don't need
but if you capture an episodic memory at
the point of Maximum uncertainty for the
singular experience right you're just
it's only going to happen once but if
you capture it at the point of Maximum
uncertainty or maximum surprise you have
the most useful point in your experience
that you've grabbed and what we see is
that the hippocampus and these other
networks uh that are involved in
generating these internal models of
events they show a heighten period of
connectivity or correlated activity
during those breaks between different
events which we call event boundaries
these are the points where you're like
surprised or you cross from one room to
another and so forth and that
communication is associated with a bump
of activity in the hippocampus and
better memory and so
if people have a very good internal
model throughout that event you don't
need to do much memory processing you're
in a predictive mode right and so then
at these event boundaries you encode and
then you retrieve and you're like okay
wait a minute what's going on here ranat
now talking about orcas what's going on
and maybe you have to go back and
remember reading my book to pull out the
episodic memory to make sense of
whatever it is I'm babbling about right
and so there's this beauti dynamics that
you can see in the brain of these
different networks that are coming
together and then deail a different
points in time that are allowing you to
go into these modes and so to speak to
your original question to some extent
when we're talking about semantic memory
and episodic memory and working memory
you can think about it as these
processes that are unfolding as these
networks kind of come together and Pull
Apart can memory be trained and improved
this beautiful connected system that
you've
described what aspect of it is a
mechanism that can be improved through
training I think Improvement it depends
on what your definition of optimal is so
what I say in the book is is that you
don't want to remember more you want to
remember better which means focusing on
the things that are important and that's
what our brains are designed to do so if
you go back to the earliest quantitative
studies in memory by ebing house what
you see is that he was trying so hard to
memorize this arbitrary nonsense and
within a day he lost about 60% of that
information and he was using he was
basically using a very very generous way
of measuring it right so as far as we
know nobody has managed to violate those
basics of having people forget you know
most of their experiences so if your
expectation is that you should remember
everything and that's what your optimal
is you're already off because that's
just not what human brains are designed
to do do on the other hand what we see
over and over again is that the brain
does basically one of the cool things
about the design of the brain is it's
always less is more less is more right
it's like I mean I've seen estimates
that the human brain uses something like
12 to 20 watts you know in a day I mean
that's just nuts the low power
consumption right so it's all about
reusing information and and making the
most of what we already have and so um
that's why basically again what you see
biologically is you know neuromodulators
for instance these chemicals in the
brain like neopine phrine dopamine uh
serotonin these are chemicals that are
released during moments that tend to be
biologically significant surprise fear
stress Etc and so these chemicals
promote lasting plasticity right
essentially some mechanisms by which the
brain can say prioritize the information
that you carry with you into the future
attention is a big factor as well our
ability to focus our attention on what's
important and so uh there's different
schools of thought on training attention
for instance um uh so one of my
colleagues amishi jaw she wrote a book
called Peak mind and talks about
mindfulness as a method for improving
attention uh and focus uh so she works a
lot with military like Navy Seals and
stuff to do do this kind of work um with
mindfulness meditation um Adam gazali
another one of my friends and colleagues
has work on kind of training through
video games actually as a way of
training attention and so uh it's not
clear to me you know one of the
challenges though in training is you
tend to overfit to the thing that you're
trying to optimize right so you tend to
if I'm looking at a video game I can
definitely get better at paying
attention in the context of the video
game but you transfer it to the outside
world that's very controversial
the implication there is that attention
is a fundamental component of
remembering something allocating
attention to it and then attention might
be something that you could train how
you allocate attention and how you hold
attention on a thing I can say that in
fact we do in certain ways right so if
you are an expert in something you are
training attention so we did this one
study of expertise in the brain and uh
you so people used to think say if
you're a bird expert or something right
people will go like if you get really
into this world of birds you start to
see the differences in your visual
cortex is tuned up and it's all about
plasticity the visual cortex and vision
researchers love to say everything's
visual you know but but it's like we did
the study of attention and working or E
working memory and expertise and one of
the things that surprised us were the
biggest effects as people became experts
in identifying these different kinds of
just crazy objects that we made up as
they develop this expertise of being
able to identify what made them
different from each other and what made
them unique we were actually seeing
massive increases in activity in the
prefrontal cortex and this fits with
some of the studies of Chess experts and
so forth that it's not so much that you
learn the patterns passively you learn
what to look for you learn what's
important what's not right and you can
see this in any kind of expert
professional athlete they're looking
three steps ahead of where they're
supposed to be so that's kind of a
training of attention and those are also
what you'd call Expert memory skills so
um if you take the memory athletes I
know that's something we're both
interested in and you know so these are
people who train in these competitions
and they'll memorize like a deck of
cards and like a really short amount of
time um there's a a great memory athlete
her name I think is pronounced yenya
winter soul but she uh so I think she's
got like a giant Instagram following and
so she had this YouTube video that went
um where she had memorized an entire
Ikea catalog right and so how do people
do this by all accounts from people who
become memory athletes they weren't born
with some extraordinary memory but they
practic strategies over and over and
over again the strategy that they use
for memorizing a particular thing it can
become automatic and you can just deploy
it in an instant right so again it's not
necessarily going to one strategy for
learning the order of a deck ofs cards
might not help you for something else
that you need like you know remembering
your way around Austin Texas but it's
going to be these whatever you're
interested in you can optimize for that
and that's just a natural byproduct of
expertise there's certain hacks there's
something called The Memory Palace that
I've played with I don't know if you're
familiar with that whole technique and
it works it's interesting so uh another
thing I recommend for people a lot is I
use anky a lot every day it's a app that
does space repetition so I think medical
students and like students use this a
lot to remember a lot of different
things oh yeah okay we can come back to
this but yeah sure it's the whole
concept of space repetition you just uh
when when the thing is fresh you kind of
have to remind yourself of it a lot and
then over time you can wait uh a week a
month a year before you have to recall
the thing again and that way you
essentially have something like note
cards the can have tens of thousands of
and can only spend 30 minutes a day and
actually be refreshing all of that
information all that knowledge it's
really great and then for uh Memory
Palace is a technique that allows you to
remember things like the Ikea catalog or
by placing them visually in a place that
you're really familiar with like I'm
really familiar with this place so I can
put uh uh numbers or facts or whatever
you want to remember you can walk along
that little pal reminds you it's cool
like there's stuff like that that I
think athletes memory athletes could use
but I think also regular people can use
one of the things I have to solve for
myself is how to remember names I'm
horrible at it yeah I think is because
when people introduce
themselves I have the the social anxiety
of the interaction where I'm like I know
I should be remembering that but I have
I'm freaking out internally about
social interaction in general and so
therefore I forget immediately so I'm
looking for good tricks for that so uh
I'm I feel like we've got a lot in
common because when people introduce
themselves to me it's almost like I have
this like just blank blackout for a
moment and then I'm just looking at them
like what happened I look away or
something what's wrong with me yeah so I
mean I'm totally with you on this the
reason why it's hard is that there's no
reason should be able to remember names
because when you say remembering a name
you're not really remembering a name
maybe in my case you are but most of the
time you're associating a name with a
with a face and an identity and that's a
completely arbitrary thing right I mean
maybe in the olden days somebody named
Miller it's like they're actually making
flower or something like that but you
know for the most part it's like uh
these names are just utterly arbitrary
so you have no thing to latch on to and
so it's not really a thing that our
brain does very well to learn
meaningless arbitrary stuff so what you
need to do is build connection somehow
visualize a connection and sometimes
it's it's obvious or sometimes it's not
I'm trying to think of a good one for
you now but the first thing I think of
is Lex Luthor but yeah so I Le doesn't
Lex Luthor wear a a suit I think I I
know he has a shaved head though he's
bald which you're not you got a great
head if I trade hair with you any day
but but like you know but something like
that but if I can come up with something
like I could say okay so Lex Luther is
this criminal mastermind and then I just
imagine you talked about stabbing or
whatever
earlier kind of connected and that's it
yeah yeah and I but I'm serious though
that these kinds of weird associations
now building a richer Network I mean one
of the things that I find is if I've
like you can have somebody's name that's
just totally generic like John Smith or
something not that no offense to people
that that name but you know I if I see a
generic name like that but I've read
John Smith's papers academically and
then I meet John Smith at a conference I
can immediately associate that name with
that face because I have this
pre-existing Network to lock everything
into right and so you can build that
Network and that's what the method of
loai or the Memory Palace technique is
all about is you have a pre-existing
structure in your head of like your
childhood home or this mental Palace
that you've created for yourself and so
now you can put arbitrary pieces of
information in different locations in
that mental structure of yours and then
you can walk through the different path
and find all the pieces of information
you're looking for so the method of Loi
is a great method for just learning
arbitrary things because it allows you
to link them together and get that cue
that you need to pop in and find
everything right we should maybe Linger
on this Memory Palace thing just to make
obvious cuz when people were describing
to me a while ago what this is it seems
insane I just you literally think of a
place like a childhood home or a home
that you're really
visually uh familiar with and you
literally place in that
three-dimensional space facts or people
or whatever you want to remember and you
just walk in your mind
along that place visually and you can
remember uh remind yourself of the
different things one of the limitations
is there is a sequence to it m so it's I
think your brain somehow you need you
can't just like go upstairs right away
or something you have to like walk along
the the room so it's really great for
remembering sequences but it's also not
great for remembering like individual
facts out of context so the full context
of the tour I think is
important uh but it's a it's fascinating
how the mind is able to do that when you
ground these pieces of knowledge into
something that you remember well already
especially visually fascinating you can
just do that for any kind of sequence
I'm sure she used something like this
for the for Ikea
catalog absolutely absolutely um and I
think the the principle here is again I
was telling you this idea that memories
can compete with each other right well I
like to use this example and maybe
someday I'll Reg at this but I've used
it a lot recently is like imagine if
this were my desk it could be cluttered
with a zillion different things right so
imagine it's just cluttered with a whole
bunch of yellow posted notes and on one
of them I put my bank password on it
right well it's going to take me forever
to find it I might you know it's just
going to be buried under all these other
posted on but if it's like hot pink it's
going to stand out and I find it really
easily right so that's one way in which
if things are distinctive if you've
processed information in a very
distinctive way then you can have a
memory that's going to last um and
that's very good for instance for name
face associations if I get something
distinctive about you you know that it's
like that you've got very short hair and
maybe I can make the association with
Lex Luthor that way or something like
that right you know but I I get
something very specific that's a great
cue but the other part of it is what if
I just organized my notes so that I have
my finances in one pile and I have my
like uh reminders my to-do list in one
pile for so I organized them well then I
know exactly if I'm going for my banking
you know P my bank password I could go
to the finance pile right so the method
of lowai works or memory palaces work
because they give you a way of
organizing um there's a school of
thought that says that episodic memory
evolved from this like kind of knowledge
of space and you know basically this
primitive abilities to figure out where
you are and so people explain the method
Loi that way and and you know whether or
not the evolutionary argument is true
the meth ofi is not at all special so if
you don't you're not a good visualizer
um uh stories are a good one so a lot of
memory athletes will use stories and
they'll go like if you're memorizing a
deck of cards they have a little code
for the different like uh um like the
king and the Jack and the 10 and so
forth and they'll make up a story about
things that they're doing and that'll
work songs are a great one right I mean
it's like I can still remember there's
this obscure episode of the TV show
Cheers they sing a song about Albania
that he uses to memorize all these facts
about Albania I could still sing that
song to
you it's just I saw it on a TV show you
know uh so what you mentioned space
repetition so what um do you like this
process maybe can you explain it oh yeah
if I'm trying to memorize something
let's say if I have an hour to memorize
as many Spanish words as I can if I just
try to do like half an hour tomorrow and
then I later in the day I do half an
hour I won't retain that information as
long as if I do half an hour today and
half an hour one week from now and so
doing that extra spacing should help me
retain the information better now
there's a interesting boundary condition
which is it depends on when you need
that information so many of us you know
for me like I I can't remember so much
from college and high school cuz I
crammed cuz I just did everything at the
last minute
and sometimes I would literally study
like you know in the hallway right
before the test that was great because
what would happen is is I just had that
information right there and so actually
not spacing can really help you if you
need it very quickly right but the
problem is is that you tend to forget it
later on but on the other hand if you
space things out you get a benefit for
later on retention and so there's many
different explanations we have a
computational model of this it's
currently under revision um but in our
computer model what we say is is that an
easy maybe a good way of thinking about
this is this conversation that you and I
are having It's associated with a
particular context a particular place in
time and so all these little cues that
are in the background these little
guitar sculptures that you have and that
big light umbrella thing right all these
things are part of my memory for what
we're talking about the content so
now later on you're sitting around and
you're at home drinking a beer and
you're thinking God what a strange
interview that was right so now you're
trying to remember it but the context is
different so your current situation
doesn't match up with the memory that
you pulled up there's error there's a
mismatch between what you pulled up and
your current context and so in our model
what you start to do is you start to
erase or alter the parts of the memory
that are associated with the specific
place and time and you heighten the
information about the content and so if
you remember this information in
different times and different places
it's more accessible at different times
and different places because it's not
overfitted in a in an AI kind of way of
thinking about things it's not
overfitted to one particular context but
that's also why the memories that we
call upon the most also feel kind of
like they're just things that we read
about almost you don't vividly reimagine
them right it's like they're just these
things that just come to us like facts
right yeah and it's a little bit
different than semantic memory but it's
like basically the these events that we
have recalled every you know over and
over and over again we keep updating
that memory so it's less and less tied
to the original experience but then we
have those other ones which it's like
you just get a reminder of that very
specific context you smell something you
hear a song you see a place that you
haven't been to in a while and boom it
just comes back back to you and that's
the exact opposite of what you get with
spacing right that's so fascinating so
with space repetition one of its powers
is that you lose attachment to a
particular
context but then it
loses the the intensity of the flavor of
the memory MH that's interesting that's
so interesting yeah but you know at the
same time it becomes stronger in the
sense that the content becomes stronger
yeah so it's used for uh for learning
languages for learning facts for
learning for you know for that generic
semantic information type of memories
yeah and and I think this this falls
into a category we've done other
modeling um one of these is a published
study in pla computational biology where
we showed that uh another way which is I
think related to the spacing effect is
What's called the testing effect so uh
the idea is is that if you're trying to
learn words uh let's say in Spanish or
something like that and this doesn't
have to be words it could be anything
you test yourself on the words and that
act of testing yourself helps you retain
it better over time than if you just
studied it right and
so from traditional learning theories
some learning theories anyway this seems
weird why would you do better giving
yourself this extra error from testing
yourself rather than just you know
giving yourself perfect input that's a
replica of what it is that you're trying
to learn and I think the reason is is
that you get better retention from that
error that mismatch that we talked about
right so what's happening in our model
it's actually conceptually kind of
similar to what happens with back propop
in uh AI so or neural networks and so
the idea is is that you expose here's
the bad connections and here's the good
connections and so we can keep the the
parts of the cell assembly that are good
for the memory and lose the ones that
are not so good but if you don't stress
test the memory you haven't exposed it
to the error fully and so that's why I
think this is kind of this is a thing
that I come back to over and over again
is that you will retain information
better if you're constantly pushing
yourself to your limit right if you are
feeling like you're coasting then you're
actually not learning so it's like
always you should always be stress
testing the memory system yeah and feel
good about it you know even though
everyone tells me oh my memory is
terrible in the moment they're over