Lisa Genova How your memory works and why forgetting is totally OK TED
Transcriber:
Thinking about the past week,
did any of you forget
where you put your phone?
Did you have a word
stuck on the tip of your tongue,
you couldn’t remember the name of an actor
or that movie a friend recommended?
Did you forget to take out the trash
or move the laundry
from the washer to the dryer
or to pick up something from
the grocery store you meant to buy?
What is going on here,
is your memory failing?
It’s not.
It’s doing exactly
what it’s supposed to do.
For all its miraculous,
necessary and pervasive
presence in our lives,
memory is far from perfect.
Our brains are not designed
to remember people’s names,
to do something later
or to catalogue everything we encounter.
These imperfections are simply
the factory settings.
Even in the smartest of heads,
memory is fallible.
A man famous for memorizing
over 100,000 digits of pi
can also forget his wife’s birthday
or why he walked into the living room.
Most of us will forget the majority
of what we experienced today
by tomorrow.
Added up, this means we actually
don’t remember most of our own lives.
Think about that.
So what determines what we remember
and what we forget?
Here are two examples
of supercommon memory failures
and why they’re totally normal.
Number one, where did I put my phone,
my keys, my glasses, my car?
The first necessary ingredient
in creating a memory
that lasts longer than the present moment
is attention.
Your memory is not a video camera
recording a constant stream of every sight
and sound you’re exposed to.
You can only remember
what you pay attention to.
Here’s an example
that will probably feel familiar.
I often drive from Boston to Cape Cod.
About an hour into this trip
I cross the Sagamore Bridge,
a really big, four-lane,
cannot-miss-it structure.
And then about 10 miles
and a mere 10 minutes later,
I’ll suddenly wonder, wait,
did I already go over the bridge?
I can’t recall going over the bridge
because that memory was never created
in the first place.
It’s not enough for my senses
to perceive information.
My brain can’t consolidate any sensory
information into a lasting memory
without the neural input of attention.
So because I’ve driven
over that bridge countless times
and because I was probably lost in thought
or listening to an audio book,
so my attention pulled elsewhere,
the experience of driving over it
slipped out of my brain within seconds,
gone without a trace.
The number one reason
for forgetting what someone said,
the name of a person you just met,
where you parked your car
and whether you already drove
over a really big bridge
is lack of attention.
Number two,
“Oh, what is his name?”
One day I couldn’t come up with the name
of the actor who played Tony Soprano
in the HBO series “The Sopranos.”
I knew his name was stored
somewhere in my brain,
and I could tell you
all kinds of things about him,
but I could not produce his name.
I eventually gave up and googled it.
“Actor who played Tony Soprano.”
James Gandolfini.
Yes, that’s it.
Blocking on a word,
also called tip of the tongue,
is one of the most common
experiences of memory failure.
You’re trying to come up with a word,
most often a proper noun,
but you cannot, for the life of you,
retrieve it on demand.
Why does this happen?
Blocking on a word can occur
when there’s only partial
or weak activation of the neurons
that connect to the word
you’re looking for.
We often come up with a loosely
related word instead,
something similar in sound or meaning.
These obliquely related words
are rather unfortunately called
the ugly sister of the target.
And even more unfortunately,
zeroing in on an ugly sister
will only make the situation worse.
These decoys lead your brain activity
down neural pathways that go to them
and not to the word you’re looking for.
So now when you try to retrieve
the word in question,
all you can come up with
is the ugly sister.
Here’s an example.
I recently asked my boyfriend,
“What’s the name of that famous surfer?
Lance?
No, it’s not Lance.”
He knew who I was talking about,
but he couldn’t come up with it either.
We were both stumped.
And turns out my blurting out
the wrong name
set my boyfriend’s brain
to Lance Armstrong,
the ugly sister.
Now, he was stuck in the wrong neural
neighborhood and couldn’t get out.
The ugly sister also explains
this phenomenon.
Much later, once you’ve stopped
trying to find the word,
it suddenly bubbles to the surface,
seemingly out of nowhere.
Laird Hamilton.
Yes, that’s it.
Why does that happen?
By calling off the hunt,
your brain can stop
perseverating on the ugly sister,
giving the correct set of neurons
a chance to be activated.
Tip of the tongue,
especially blocking on
a person’s name, is totally normal.
Twenty-five-year-olds can experience
several tip of the tongues a week,
but young people don’t sweat them,
in part because old age,
memory loss and Alzheimer’s
are nowhere on their radars.
And unlike their parents,
they don’t hesitate in outsourcing
the job to their smart phones.
Which brings me to an important point.
Many of you are worried that if you use
Google to look up your blocked words
then you’re cheating
and contributing to the problem,
weakening your memory.
You’re worried that Google
is a high-tech crutch
that’s going to give you digital amnesia.
This belief is misinformed.
Looking up the name
of the actor who played Tony Soprano
doesn’t weaken my memory’s
ability whatsoever.
Likewise, suffering through
the mental pain
and insisting on coming up
with his name on my own
doesn’t make my memory stronger
or come with any trophies for doing so.
You don’t have to be a memory martyr.
Having a word stuck
on the tip of your tongue
is a totally normal glitch
in memory retrieval,
a byproduct of how
our brains are organized.
You wear glasses if your eyes
need help seeing,
you have my permission to use Google
if a word is stuck
on the tip of your tongue.
Memory is amazing
and is essential for the functioning
of almost everything we do,
but it will also forget
to call your mother,
where you put those glasses,
and what you ate for lunch last Tuesday.
Frustrating, but not a cause
for diagnosis, panic or shame.
Most of what we forget
is just a normal part of being human.
Thank you.
David Biello: I will stand in
for the audience
to give you my own
personal standing ovation.
I personally feel so much better.
So thank you for that.
I think we all get a little concerned
about our memories,
particularly after this pandemic.
And I see that we already have
some questions from the audience.
But before we get into that, I have to ask
one very important personal question,
which is, should I be worried,
because every time I get up
and go to another room,
I forget why I’ve gone there.
Is that is that troubling?
Should I be nervous?
LG: No, you should not be nervous.
And that’s one of the big take-homes
of why I wrote the book I just wrote,
there’s so many people,
especially over the age of 40,
who experience normal
moments of forgetting
but now we are keyed into it
and we think, “Oh, my God,
does this mean I’m losing my mind,
I’m going to get Alzheimer’s.”
So here’s what happens
when you have that –
so you’re in your bedroom
and you’re getting ready to read a book,
it’s bedtime,
that’s what you do before bed.
And you realize
you’ve forgotten your glasses.
And you’re like,
they’re probably in the kitchen.
So you go walk down to the kitchen
and you created the memory,
the intention of what you
plan to do later.
That’s called your prospective memory.
So it’s like, I intend –
we do this all the time, right?
“When I go to the grocery store later,
I need to buy milk.”
“I need to remember to call my mother.”
“I need to remember to pick up
the dry cleaning,” right?
These things that we plan
to do in the future.
Our brains are terrible at them,
like, inherently terrible.
So people feel like they’re cheating
if they create to-do lists, checklists,
put it in their phone.
No, this is just good practice, right?
So pilots don’t rely
on their prospective memories
to remember to put down the wheels
before landing the plane.
They outsource the job.
Don’t use your brain,
use the checklist, right?
So, like, using a checklist
is sound practice.
So anyway, you made this intention,
this memory of, like,
when I get to the kitchen,
I’m going to look for glasses.
You show up in the kitchen,
you’re like, “I don’t know why I’m here.”
Part of the reason is
prospective memory sucks.
But we’ve only asked it
to remember something for 10 seconds.
It’s not like, “Oh, I need to remember
to go to my Zoom meeting at four o’clock.”
So what’s going on?
The other key in this situation
has to do with context.
So memory is very much
influenced by context.
The cues, the associations,
the sensory information,
the emotional information, our mood,
anything that is linked to the thing
we’re trying to remember.
So context helps us form a memory
and context helps us retrieve that memory
because memory is the connected
neural network of associations.
So in the bedroom, all the cues
for what you needed were there, right?
The bookcase, the book you’re reading,
the time of day, it’s bedtime,
“Oh, I need glasses.”
You show up in the kitchen
and you’re like,
“Am I hungry? Am I thirsty?”
Because, right, the cues are signaling,
“Is it a meal? Is it what?”
And not the glasses
that you didn’t notice.
So when you walk
into the room and you’re like,
“I don’t know why I’m here,”
you’re not going crazy,
you’re not getting Alzheimer’s,
your memory isn’t terrible.
It’s, go back to the room you were in
before you landed in this one,
either in your mind’s eye
or physically do it
and imagine the cues that were there
and it will instantly deliver
what you were completely
befuddled by a moment ago.
DB: So a question that’s come in
from a number of our audience members,
including Mel and Lorraine,
is the flip side of this.
So when would you consider,
or what kinds of memory cues
would be signs of abnormality
or you should get further
testing and checking?
LG: Oh, I love this question, too,
because I think that for too long
there’s been this disconnect with,
you know, people are comfortable thinking
about having an influence
over their health
from the neck down, right?
So especially with heart health,
a lot of us count our number of steps
or we’ll go to the doctor
and get blood pressure taken.
And do we have high cholesterol?
How can I influence these factors, right?
How can I influence the likelihood
that I’ll get a heart attack later?
But most people don’t think they have
any influence over their brain health.
And so this question is great
because it’s like,
well, what can I notice?
And then what do I do
with that information, right?
So, like, don’t just panic
and don’t tell anyone.
There’s so much shame and stigma attached
to anything going on with the brain
and particularly memory.
But this becomes information
that you can be in conversation
with your doctor about.
So what is your cognition?
What is your memory today
and what does it look like
a year from now?
Is it changing?
And so what are the differences?
So forgetting people’s names,
totally normal.
Names sort of, live in, like,
little neurological cul de sacs
like, ultimately lots of things
connected to them,
but really hard in the end
to just produce the words,
you’ve got to get to that house
at the end of that street,
there’s only one way in.
Whereas common names,
common nouns are like,
in the intersections on Main Street, USA,
like, you can get, there are
a number of different ways,
and it’s super easy to get in and out.
If you start forgetting
common words frequently –
so if I’m like, “Oh, what’s the name
of the thing you write with?
The thing you write with. What’s that”
“Pen?” “Yeah” –
if that starts happening,
that could be something.
Doesn’t have to be Alzheimer’s.
There are lots of reasons
for having issues with retrieving memories
making new memories.
It can be sleep deprivation,
it could be B12, it can be lots of things.
So you don’t have to just
jump to Alzheimer’s.
But it is something
that you can hopefully address.
Again, be involved in your brain health.
The other has to do
with understanding how things work,
what things are for.
So, like, my friend
Greg O’Brien has Alzheimer’s
and he uses the example
which I love and I used in my book is,
a lot of people say I can’t remember
where I parked my car.
That happened to me the other day.
I was in the mall, I got out,
I couldn’t remember where
in the garage I parked the car.
I’ve certainly done this.
For Greg, who has Alzheimer’s,
it’s he drives somewhere,
back when he used to drive,
parks his car, gets out,
like, does something for a minute.
So his example’s the dump.
“I went to the dump, threw the trash out,
turned around standing in front of my car.
Don’t recognize it as mine.”
So that’s a semantic memory.
That car is my yellow jeep
and I don’t recognize it.
And then B, forgets that he drove there.
So that’s an episodic memory,
a memory for what happened.
So just a few minutes ago,
I drove to the dump and now
I don’t remember that I did that.
And so that’s not the same as, like,
“Did I park on level four or five?”
DB: Yeah.
So George Weiss,
in the helping-us-remember-better vein,
wants to know can diet help us
to avoid memory loss
and can you, kind of, exercise
your neurons into better memory
through crossword puzzles
or deeper relationships
or anything like that?
You’re shaking your head no,
so that’s the short answer.
LG: Yes and no. Again, I love
this question, so thank you.
Yeah, so I tell folks, like,
there’s no real gimmick to this,
like there’s no supplement I can give you
that’s going to keep you
from experiencing a tip of the tongue
or help you memorize your next TED Talk.
Like, there’s no supplement,
the crossword puzzles are not the thing,
I don’t know who started that one.
So crossword puzzles are going to –
think about what you’re doing –
you’re retrieving words you already know.
So you’re going to get better
at remembering those words.
But it’s not cross-training.
It doesn’t then help you
in your day-to-day life
remember what happened that day
or again, if you have a presentation,
what you have to say.
It doesn’t work that way.
It’s also not building new neural roads.
So retrieving information you already know
doesn’t lend itself
toward neuroplasticity,
which is in building something
called a cognitive reserve.
So every time we learn something new,
we’re actually building new
neuroanatomical
and neurochemical connections.
And so if you imagine –
your brain isn’t just this
pink blob in your skull,
in this little black box in your head,
it’s a very dynamic organ
and it’s changing constantly.
And your genes are interacting
with what happens.
It’s interacting with what you do
and experience and feel,
and it changes.
And the more we learn,
the more connections we build.
And this is important
because if you do start
to experience some pathology,
that is sort of, pre-Alzheimer’s,
or if you start to get Alzheimer’s,
you actually have a lot of reserve.
You have back-up connections
that can dance around
any problems or detours.
So learning new things is one way.
Exercise has been shown
to decrease your risk of dementia
by up to a half.
Just day-to-day,
we know that sleep is massively important,
both for preventing Alzheimer’s
and for your memory today.
So the memories that I make today
become long-term, stable memories,
become long-term, stable alterations
and neural connections while I sleep.
And it’s during certain phases of sleep
that this process happens.
So sleep is not this passive state
of doing nothing.
It’s a very busy biological state.
And so it’s locking in the information
and experiences you learn today.
And so that’s superimportant.
Then tomorrow, if I didn’t get
enough sleep tonight,
I’m going to –
my frontal lobe’s not going to want
to drag itself into its day job
and do the work of paying
attention today, right?
You feel sluggish, like,
“Ah, I can’t pay attention. What?”
If I can’t pay attention,
what’s not going to happen today?
Making new memories.
So I’m not going to remember yesterday,
I’m not going be able to make
new memories today,
I have a form of amnesia
just from not getting enough sleep.
DB: Right.
LG: So seven to nine hours
a night has been shown –
the science is superclear
that this is what we need minimally
as a human species.
And then in terms of what you eat,
again, there’s no perfect study,
and there’s no rabbit-out-of-a-hat
I can pull for you,
or of, like, if you eat this
or this nutrient,
this antioxidant, this recipe,
it’s going to save your memory.
It’s like, no, but we know
there’s been enough to show us
that being on a Mediterranean
diet, a mind diet
so these leafy vegetables,
the brightly-colored foods,
the whole foods,
fatty fishes, olive oil, nuts, beans,
these are the kinds of foods
that really fuel and support heart health,
brain health and memory.
And it doesn’t have to be
100 percent, folks, right?
You’re not going to be perfect at this,
and that’s OK.
Try to do it overall, right?
Today, what did I eat overall?
This week, how did I do overall?
Because I think we need to have
realistic expectations.
So exercise,
the diet, sleep and stress
and learning new things.
And learning new things is also –
it’s this, it’s being around people.
If you’re in conversation,
that conversation’s never happened before.
So if you’re present and paying attention,
your brain is getting a lot
of stimulation that’s superhelpful.
DB: So Bob wants to know
about our capacity, our brain capacity.
Do we have like a lifetime capacity
and we hit it and then that’s kind of it,
or is that why children seem
to remember things better
than maybe folks of my age?
Or is that just,
I don’t know, an urban myth?
LG: Yeah, it’s myth.
This idea that like, oh,
you only use 10 percent of your brain
or you only use
five percent of your brain,
someone’s making it smaller.
I don’t know who started that one, either.
That’s not true.
So, you know, at any given moment,
I’m using certain parts
of my brain, right?
So I’m not in a rage right now,
so my amygdala is kind of chilling.
Like, I’m not grief-stricken,
so my amygdala is kind of relaxed,
and I have my eyes open,
so my visual cortex is lit up,
and neurons there are firing.
And if I were to close my eyes,
that part of my brain goes quiet.
But all of my brain is being used at some
point throughout the day, probably,
or certainly capable of accessing it.
There aren’t parts of my brain
that I just can’t seem to use
and I’m only squirreled away
into certain domains.
That is a fallacy.
And no, you don’t run out of room.
So, you know, there’s a man,
I use his example in the book,
Akira Haraguchi,
a retired engineer from Japan
who at the age of 69,
he’s the guy who memorized over
100,000 digits of pi, right?
So at an age where we associate,
like, you know, senior discounts
and retirements,
like, he’s doing something
that is kind of completely mind-blowing.
And we can all do this if we wanted to.
So no, at any age, you’re capable –
So as you grow older,
you don’t lose the information
of stuff you’ve learned.
So the stuff, your semantic memory.
So this is why you’ve accumulated
a body of knowledge
and you’ve got wisdom now, right?
Because now you know how it all fits
and you can use that wisdom
you’ve collected.
You’ve got that.
It’s not that that starts to go away.
You accumulate that.
And you might think like,
“Oh, I don’t remember much from childhood.
I can’t really think about,”
like, “I can’t tell you
what happened when I was 10.”
This has more to do with context.
It’s still in there.
So if, you know, if you live
in New York and you’re, you know,
you’re surrounded
by skyscrapers and city life
and you grew up in rural Vermont,
“And I can’t remember
what happened when I was 10.”
Go back to your neighborhood
and drive around and,
there’s the willow tree,
and there’s Ms. Richards house,
and there’s Ms. Molansen,
oh, that’s where, like,
Joey broke his leg,
and like, it all will come back,
because, again, it’s like going
from your kitchen to your living room,
your bedroom to your kitchen
to look for the glasses.
It’s like, all that context will reveal
memory that you have in your head.
you didn’t realize you have.
You’ve got trillions
of possible connections.
And no, you will not run out.
You can learn to juggle when you’re 80.
You can learn to play piano.
You can learn a new language.
You can listen to a new TED Talk
and learn and remember something
to share with someone else.
Like, it’s unlimited.
There’s no reason to think
there’s a limit to it.
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