Translator: Hiroko Kawano Reviewer: Peter van de Ven
I want to take you on an adventure
into the weird world of memory hacking.
What I want you to do is to rethink memory.
I want you to think about your memories,
rather than as accurate recollections, permanent records of the past,
instead of that, I want you to think of your memories as stories.
Stories that you tell yourself to make sense of your life -
why you're here; who you are -
stories that you tell other people, part of your tribe,
showing that you're part of the group:
this is who we are.
But before I begin this journey into memory science
and understanding how easy it is to distort these stories,
I'm going to tell you a little anecdote.
It starts with my mom and it ends with my aunt.
So here is the situation:
My mom went to Switzerland.
On this trip to Switzerland, she went into - well, to get her car,
and she was in a garage underground.
She gets into the passenger seat of her car.
My father gets into the driver's seat.
They try to exit the garage.
On the way out,
there is a man standing at the exit, blocking their way out of this garage.
He's clearly not well;
he's talking to himself;
he's disheveled.
And my mom, to try to get him out of the way,
gets out of the car and says, "Sir, can you please get out of the way?"
And the man, instead of responding the way that normal people would,
which is by moving,
he runs at my mom,
pushes her into the car,
and starts punching her.
Now, my dad's response to this is to drive away -
of course, everyone's in shock -
and they get out of the situation, and my mom is okay.
But of course, for my mom,
this was an earth-shattering moment.
A stranger randomly attacked her,
this kind of thing had never happened to her.
So what does she do?
Naturally, she tells her family about it;
she tells her friends about it;
the story is told full of emotion.
Now, a year later,
my aunt is telling the same story
full of emotion,
full of confidence and conviction,
full of details
and claims that she was in the backseat.
Now, that's impossible.
I said this story happened in Switzerland, and my aunt lives in Germany.
Even when confronted with this fact
that there is no way she could have possibly been in the back of this car,
she doesn't want to let go of this memory,
because it feels so real.
So how do we find ourselves in a situation
where we confuse things that we think we've experienced -
our memories -
with things that we have actually experienced?
So this is where I'm coming from;
this is where our stories begin.
And so if we rethink our past as a story,
and we think about writing these stories and who gets to write these stories,
who gets to write into our memory box?
It might be a little more complicated than we often think.
And ultimately what we find is
that just like my aunt was not actually the witness of my mom's crime -
as much as she might identify as this witness;
this may have been an important part of her personal narrative -
it's not true.
And the same thing goes for you:
that there might be important moments of your life -
memories of your childhood, memories of lost loves -
that don't make sense at all.
And so you might not actually be the person you think you are,
certainly if you're resting your identity on your memories.
So I want you to dare to question your memories.
And no memory is off-limits.
Just because it's emotional or complex, just because it feels real
doesn't necessarily mean that it is.
So question your memories:
"How do I know that this actually happened?"
Because when you do that, you dare to question yourself: "Who am I?"
And if you can't trust your memories,
What then?
And ultimately it leads you to question your reality.
So let's talk about that.
What is your reality?
So, before we even begin to talk about distorting memories,
let's talk about where memories begin.
Memories begin at perception.
That doesn't need to be perception of the real world,
that can be perception, that can be idea,
that can be something that we think about -
because we can also remember things we've thought about or dreams -
but often we talk about perception in real life.
And of course, here, neuroscience and people who study psychology,
like myself,
are clear that you have a unique perceptual filter.
Every one of you has a different set of eyes,
different set of ears, different smells.
But that's not where it ends.
You also have a different worldview.
You have a completely different set of memories
that you bring into every situation,
and those matter.
You could even argue that we're living in a simulation.
Reality as you know it
only exists to you.
And so, from their very inception, from the very beginning of a memory,
it's already filtered, it's already tainted.
Let me give you an example
of how perception can filter how we make decisions
and ultimately how those memories of our lives,
of things that we think are important,
can change how we make decisions.
So, all right.
This is a study I did with Stephen Porter, Leanne ten Brinke and Natasha Korva
and published in 2013,
where what we did is we gave participants a photo.
And we said, alongside this photo,
this person was a murderer.
This person, or at least is convicted - oh, not convicted -
is a suspect in a murder case.
So this suspect, we give you the case,
we give you pieces of evidence,
11 pieces of evidence in increasing severity.
Now, what we find is that people, generally, the more evidence they get,
the more likely they are to convict someone.
And that makes sense.
But there is one important difference
in terms of how many pieces of evidence you need to convict someone,
and that has to do with how trustworthy the picture of the person's face is.
So you look at someone, and in that moment,
you make a snap decision:
"I trust this person," or "I don't trust this person."
And you're basing that decision,
as to whether or not this person might be capable
of this horrendous crime that were accusing him of,
just based on your memories.
This is, in general, what society has bombarded you with:
this is what an offender looks like.
And if a person matches that stereotype you're more likely to make a bad decision.
And so what we found is that people who look less trustworthy
need fewer pieces of evidence to have a juror reach a guilty verdict,
and - and this is what's most important, I think -
is that when you give people exonerating evidence,
when you give people an 11th piece of evidence
that says, actually, the DNA in this case doesn't match the suspect -
arguably most people would say, "Oh, that makes sense to them,"
say, "Oh, not guilty," so to exonerate -
what we find is that trustworthy people are much more likely to be exonerated
than untrustworthy people.
So again, this perception in the moment is clouding your decision making.
And so you're bringing that to the table.
It's changing your worldview.
So perception influences our memories,
perception influences how we remember people
and how we interact with them.
And so that can be distorted.
And that can be distorted by things that we don't even notice.
But before we move on
to the penultimate thing that I want to talk about,
which is memory hacking -
which is how we can actually, actively distort people's memories -
let's also talk a bit about the brain.
Because you need to understand how the brain works
in order to understand why memories are so flexible, so slippery.
Every day, you wake up a new person.
Now, the reason for that
is that your brain is constantly changing.
From the beginning of this sentence to the end of this sentence,
your brain looks different.
And that's a good thing
because it means that you're able to be creative and to learn,
you're able to take on new information and weave it into your brain
in a way that you can possibly use later.
And so if you understand that your brain is constantly in motion,
you also understand that this hugely complex organ ...
if we break it down into a network,
into the network that is the memory,
we see that it's possible to forget things,
to remember things and to misremember things.
Now, if you think about memory as a network,
forgetting is when you cut the connection between two parts of a memory.
Now, when we talk about memories of our lives, of autobiographical memories,
what we normally talk about are things like,
"Oh, I felt this." " I heard this." " I saw this."
They're called multi-sensory details.
They're complex.
And these multi-sensory details are actually stored in networks
across the different parts of the brain
that are each responsible for those sensations,
which is why we can relive,
or feel to relive these magical times in our lives.
But when we forget, what happens is
that you've cut a connection between some of these sensations,
some of these details.
And when you misremember or you have a false memory,
which is what I study,
you reconnect pieces or connect pieces for the first time
in ways that were never originally together.
So you might think, "Oh, I remember that smell,"
but then you have it in the wrong place.
So you've connected things that aren't supposed to be together.
And that's the basis of memory errors,
is that your flexible brain is creatively recombining things.
So here we move on to the last part,
which is I think the most exciting,
which is the social influence part:
the idea that your memories are not just your own,
your memories are subject to social influence.
So back to the stories.
If you think of your memories, all of your memories,
as living in a library ...
Now, that library sucks.
It's a really bad library.
Why?
Because people can walk into the library;
they can take out the book; they can rip out pages;
they can cross things out; they can write over them.
In fact, every single time that you take a book out of your own library,
you're required to delete the whole thing and rewrite it from scratch.
And then you put it back in the shelf.
Now, this will also change depending on who you're talking to.
If you're talking to a friend, you might change your story a little bit.
You might enhance the parts
that the person is responding to positively with "uh, yeah."
And you might ignore or delete the parts where the person's going,
"This isn't very interesting."
So who we're talking to matters.
And if we arrive at my research, which I'm going to describe now,
which is that I convince people that they committed crimes
or had other emotional experiences that never happened.
Things like, you would come into my lab,
and I might convince you that you were attacked by an animal,
that you lost a large sum of money,
or that you injured yourself.
Alternatively -
because I'm a criminal psychologist -
I'm also interested in trying to convince you that you committed a crime,
a crime like attacking someone, attacking someone with a weapon
or stealing something - all with police contact.
Now, what happens in these situations is that 70% of the participants
ultimately come to accept this alternate reality,
as I've suggested it to them,
and they started to tell me - like my aunt - all about it:
This is why I did it;
here's the situation;
here's who I was fighting.
And the way it works is that I get participants to come into my lab,
and I tell them - I start with trust -
I tell them, and I say, "I've contacted your parents" -
these are university students -
"I've contacted your parents,
and they said that six years ago you attacked someone.
What do you remember?"
And they say, "I have no idea what you're talking about."
"Okay, do you want to try something?"
If a psychologist asks you if you want to try something,
be careful.
(Laughter)
And of course, everybody says yes -
"Yes, I want to try this" - because they think, and this is the key,
they think that I know something about their lives that they can't remember.
So they need to trust me
and think I actually have this information.
Then I say, "Okay, let's try this.
Imagine what it could have been like.
Let's try to dig this memory out."
And what we find is
that after repeatedly imagining the event as it could have been,
three times over three weeks,
people have an increasing difficulty
distinguishing between things that they just imagined
and things that they experienced.
And now we're back to our flexible brains,
because the reason it's so difficult to tell the difference
is that actually, in the brain,
imagined experiences and lived experiences ...
can be identical.
Especially if you get people to imagine multi-sensory components:
"What did it smell like?" "What did it feel like?"
Because that's usually what we use as the marker to distinguish the two.
So what I want is for people to move away
from the idea of truth versus lies, fact versus fiction,
at least in terms of our memories,
and to embrace that sometimes things just aren't that black-and-white.
I think this is particularly important for the legal system.
I work with the courts, and the military and police,
and I think, especially in justice settings,
we need to be very careful
not to assume that someone must be lying
just because they're saying something that's demonstrably untrue.
Because what we might have instead is a much more gray area
that's somewhere between this fact and fiction,
lie/false memories,
fiction that's woven into our stories.
So I want to leave you with this.
I want you to be cautious, curious and kind.
I want you to be cautious.
Think about how you're remembering things
and things that may have influenced how you remember.
Was there someone eagerly watching your memory?
Was there someone giving you feedback, giving you leading questions?
Was there a therapist or maybe a police officer
or maybe a teacher or parents overly zealously asking you questions
and saying, "Oh, no, no, but don't you remember this?"
Be careful as to where they came from.
Be curious when other people are remembering things and you think,
"I'm not sure if that's true."
Ask them.
"Do you have any evidence that this actually happened?"
And be kind.
Just because someone's saying something clearly untrue,
don't assume that they're lying.
This helps me with my aunt quite significantly.
(Laughter)
So I want to leave you with the idea
that you are the curator of your memories.
Only you have control over who gets to go into the library,
who gets to tear out pages and scribble over the margins.
So be careful.
Because if you let too many errors slip in,
you might realize that your memories are just an illusion.
(Applause)