Thank you. It's quite a privilege to be here today.
I'm going to start with this picture here and see if anyone in this room -
let's start with a show of hands -
knows what this picture is depicting.
Does anyone know what this is?
This is the feeling that you have after you've left the couch
with a clear idea in mind about what you wanted to get in the kitchen.
(Laughter)
You arrive there, look in the refrigerator and have no idea what you're doing.
(Laughter)
Has anyone in this room ever experienced this?
Don't be shy if you have. You could share with us.
How amazing is that,
that our magnificent brains could let us down,
that we could know exactly what we want, one single item,
and just seven seconds later, we don't remember it.
Clearly, we have the ability to remember a single item for seven seconds.
How is that possible?
How is it possible that our brains could fail us
in that very easy task of just holding one thing in mind?
The brain is the most remarkable structure we're aware of.
It's capable of incredibly rapid parallel processing,
allowing us to interpret complex stimuli in our environment
within a tenth of a second.
Even computers,
which are designed to try to do this,
have an inability to do that.
Plus, we store a massive amount of information over the course of our lives,
by some estimates, a billion bits of information -
that's 50,000 times the text stored in the library of Congress.
Despite living in a rather small space, the brain is a massive structure,
having approximately a hundred billion neurons -
that's on the order of stars in the core of our Milky Way galaxy.
What's even more impressive
is that there are hundreds of trillions of connections between these neurons,
creating a staggering network of very, very intricate complexity.
But I don't have to tell you a lot of cool facts about the brain
for you to realize how amazing it is:
every emotion you feel, every thought you have,
every sensation you experience, every move you make,
your very sense of identity -
all emerges from the function of our brains.
Despite that, the brain has some very distinct limitations.
I'll be talking about three of them.
The first is attention.
We know, just based on our experience and now an incredible amount of data,
that we cannot distribute our attention everywhere, infinitely.
We can selectively focus our attention, and that's what it's required to do:
that we direct our resources to what our goals are guiding us towards.
Another limitation is something known as working memory.
Working memory is online memory, not long-term memory.
It's the memory you use to guide your actions;
it happens during a conversation to carry the thread of what's going on.
It's also the type of the memory that you use --
in the past, when someone gave you a phone number instead of send it to you,
you had to hold it in mind until you got it into the phone.
We know that there are very strict limits on this capacity,
and they decrease as information becomes more complex.
Another limitation is speed.
Although, as I described, our brains and certainly the neurons,
if you look down at a high resolution, are capable of very rapid processing.
Because our brain functions as this massive network,
when you have very complex operations,
speed of all these areas communicating with each other becomes a limitation.
So these three limitations on our brain's abilities
leads to a sensitivity to interference.
I'm going to describe what that is.
We went and we asked folks when they had this experience -
and almost everyone describes this;
it increases as you get older, for those of you that had not noticed -
What happens?
What led you to find your way to the kitchen with a clear idea in mind
and when you got there you didn't know what you were doing,
and you could not remember what you were trying to get?
And people describe in their best experience what is happening,
and we built a conceptual framework from this.
And then we study it in our lab, I'm a neuroscientist,
we use tools to study how the brain functions,
and how that leads to higher-order behaviors.
So we built the framework based on people's anecdotes and experiences,
and then tried to pursue it empirically and see if these were really mechanisms
that influence behavior in the way people experience.
So this is how the framework goes:
we see that there's two types of interference, generally -
internal interference and externally induced interference.
We could split those each into different types of interference based on your goals.
So if the information is totally irrelevant to you,
we consider it a distraction.
Let's say you're at a restaurant having a conversation.
If you have any hopes of remembering the details of that conversation,
you know you're very busy suppressing the chatter in the room,
maybe the waiter is taking an order at the next table,
you're just trying to block that out,
it's irrelevant information,
you're trying to suppress it.
That same stimuli can serve
as what we call interruptions, or multitasking,
when you think maybe you can do more than one thing at a time.
Maybe you're having that conversation,
but now you're trying to listen
to what the specials are being announced at the next table.
Or you're on the way to the refrigerator and a phone rings;
you pick it up, and now you have to reengage in your initial task.
That's how we split external interference.
This can all happen internally as well.
Some of it is mind wondering:
your thoughts leave your focus against your will, irrelevantly,
just travel to places that you did not intend them to.
Or you could be multitasking internally.
Perhaps you're doing it now:
you pay attention to what I'm saying,
you look at the slides, listening to me,
but you might be planning what to have for lunch later
and who you're going to meet in the afternoon.
So this constant interference keeps us from being present, directed on our goals.
So, given those limitations of our brain and our susceptibility to interference,
what happens when you take your brain and you expose it to this?
(Laughter)
You're probably all familiar with most of these things.
The last several decades have literally seen
an explosion of the diversity and accessibility of electronic media,
and the devices that deliver it, many of which are portable.
Probably most of you have a computer in your pockets right now
that allows you to access this at any moment.
What's even more profound, it's not the change in technology,
but historically one media has replaced other medias.
That's not what's happening now.
Now, data shows, I'm sure you're all aware of it,
that people are using medias at the same time.
Approximately 95 percent of people
report using more than one form of media at a time,
and that activity takes place almost 30 percent of your days.
Children might probably have this even more so,
although it's just beginning to be investigated now.
Almost an obsessive media multitasking frenzy -
you're almost uncomfortable
when taken away from your ability to interact with technology in this way.
Before I move forward, I want to say that I'm a friend of technology,
I'm not anti-technology; I use all these wonderful toys as well as you do.
Here I am, working on this talk; I've two large computer monitors,
email on the left side, cell phone in hand accepting texts,
music playing in the background.
This is how we all interact with technology, at least to some degree.
Some people have up to six or more forms of media at any given time.
Another thing that's changed are expectations.
This constant access to communications,
computers and data has really changed societal expectations.
Now immediate responsiveness and continuous productivity are expected.
How many of you are on vacation and check your email?
A little dark in here, but I just see a lot of movement out there.
So I'll take that as a resounding ''yes,'' right.
So we know that our ability to disconnect,
to really be present in what we're experiencing is decreasing,
even when we're "taking vacations,"
the break from all of this constant productivity.
So, we should ask the question: how do we function at all?
Given those limitations and how we interact with technology,
how are we capable of getting anything done?
I want to tell you about the process of cognitive control.
Cognitive control is what allows us to function at least to some degree
under these circumstances.
How we perceive the world is not a passive process.
Our environment just doesn't flood into our brains.
It's sculpted and shaped by our attention.
Two types of attention:
One attention is external, stimulus-driven attention,
it is the environment imposing itself upon how you perceive the world.
If there's a flash of light, a loud sound,
even if someone calls your name quietly behind you,
you pay attention, you redirect your attention.
Anything that's very salient or novel demands your attention
and increases your perception of it.
The other type of attention -
the environment coming in is also known as bottom-up attention.
The other type is internal, goal-directed attention,
what you're doing now.
You're choosing to focus your cognitive resources
on what you're hearing and what you're seeing.
This is known as top-down attention,
your goal-directed attention.
All of your interactions with the environment involve this balance
between these two forms of attention that are dictating your perception.
And now we know from a lot of research, a lot of it from our lab also,
is that this influence then goes on and influences what you remember,
both in the short-term and in the long-term.
So what happens when all this interference that we are being exposed to now
exceeds the capabilities of our cognitive control?
Well, what we now realize is that there is a broad and deep influence:
safety, family, our social development, workplace, education.
All of these things are affected.
There's not nearly enough time in this talk to talk about these
since each one of these can have their own lecture associated with them,
showing you how broad this issue is.
What I'm going to talk to you about in detail is cognition,
because this is what we study in our lab, specifically memory.
There's a really beautiful quote by Samuel Johnson,
who was a British author in the 1700s.
He wasn't a psychologist, he wasn't a neuroscientist,
but he was incredibly insightful.
He said something that really showed a profound awareness,
because there was no data on this at the time.
What he said is that "the true art of memory is the art of attention,"
that "no man will read with much advantage
who is not able, at pleasure, to evacuate his mind,"
that "if the repositories of thought are already full,
what can they receive?"
And "if the mind is employed on the past or the future,
the book will be held before the eyes in vain."
There's a full career of research studies here.
We're slowly working our way through these
to show what's going on in the brain that leads to this,
and how true is this to our behavior.
So, I figured the easiest way to do this
is to have you perform one of our experiments right now,
so you can get an idea of what we do.
And while we do this, we'll record brain activities.
You'll do a less demanding version of this,
where you're not shoved inside one of our scanners.
What we are going have you do now is "Remember a face," very simple experiment.
One face will come up,
it comes up pretty quickly, so be ready for it.
Then around 7 seconds will pass, there will be an X on the screen,
and you should remember the face - just one face.
Then another face comes up, and your job is be to say,
"Yes, that's the face I saw," or "No, that's a new face."
O.K.? Ready to give it a shot?
(Audience) No.
No. The answer is no.
If any of you thinking yes,
do not be nervous,
no reason to make a clinic appointment right now.
It takes practice to get used to this, people don't always get a 100 percent.
I'm going to have you do another version of this experiment, it's the same thing -
see a face, after a period of time
another face'll come up and you'll have to see if it matches.
But in this experiment, another face will pop up in the middle,
and for that face you'll have to make a decision: is it a male over 20?
Then you go back to the business of remembering that first face.
Does that make sense?
(Laughter)
Remember one face and make a decision on the middle face.
Pretty simple. Give it a shot.
(Audience) Yes.
It was the same face.
So, did this seem a little harder to you?
(Audience) Yes.
It is a little harder.
If you study even healthy 20-30-year-olds, you see that the performance diminishes
when you introduce that second task,
even though it's not a hard experiment.
Not only that, but if you introduce a face in the middle
that's totally irrelevant, your performance also drops -
very subtle, but consistently.
If you happen to be older than 60,
your performance drops even more from the distraction
and even more so from the interruption.
So we see that there's an exaggerated effect with age of this impact
that's even there in 20- and 30-year-olds.
We are now looking at how this type of distraction and interruptions
might affect your long-term memory.
So we did an experiment where we showed our participants a series of 168 pictures
that had different numbers of objects.
So what you see here are 3 crowns, 4 couches, that's 4 vacuum cleaners -
though they look like Statues of Liberty every time I look at that slide.
But you see all these pictures, and then, after an hour,
you go inside our MRI scanner
so we could see what's happening in your brain,
and you hear these names:
"Crown," and when you hear "Crown,"
you have to press the button on how many you remember seeing.
Here the correct answer would be 3, or it might be new,
maybe we never showed that one before.
The interesting thing is that we look at what happens to your memory
when your eyes are shut,
when they are open looking at a grey screen,
and when your eyes are open looking at a busy visual picture.
And what we found is that the detailed quality,
your recollection of those details decline
just by having your eyes open looking at a picture,
which is basically what you do all day long.
Just that very simple stimulus,
that you have nothing to do besides remember,
declines just by having your eyes open.
Later, you should do this experiment:
Go up to a significant other or a friend, look them in the eyes,
and ask them to tell you in detail what they had for dinner last night.
Almost invariably, what you'll see is that they look away from you.
What we think is going on from looking at the brain data
is that people are looking for a quiet place in their environment
to recreate this memory.
Just looking at your face
is too distracting to do this at a high level.
(Laughter)
Nothing personal.
We did another experiment, where it was basically the same,
but now it was done in silence, or we went into a restaurant
and we taped the normal chatter that occurs in a restaurant,
and we found the same decline in memory.
The point of this
is not that you should walk around with blindfolds on and earplugs in.
The point is to show you how exquisitely sensitive our memory is
even to the normal environmental stimulation that we cannot escape.
So you can imagine
when you layer upon all the normal complexity that exists in our environment.
But we do this, the reason we make such simple experiments
is we're recording brain activity with these tools:
functional MRI that lets us look at blood flow correlates of neural activity
and lets us see where in the brain events are occurring;
as well as EEG, in which we're looking at electrical signatures of neural activity,
where we can see when events are occurring.
And we do these tools
to understand what happens in our brain when we have interference
and how it diminishes our abilities.
I'm just going to summarize this with a couple of cartoons,
data from our lab and so many labs
to give you the latest understanding about what's going on.
This is your brain.
The front part is over here on this side,
and what we see is that the prefrontal cortex -
that's the part of our brain that makes us most human,
the part that's evolved the most, the part that develops the latest,
it's the part that's involved in this cognitive control.
And when you're confronted with distraction, it acts as a bouncer.
It's saying, "What information is on the guest list?"
And through its connectivity in a network with visual parts of the brain,
which are in the back,
it controls what information gets in.
You can see this is a very busy night club,
but your visual cortex will only fit six things or even less at a time,
depending on how complicated they are.
When information gets in that's not on the guest list,
you have a cost - your performance drops.
This is what changes as we get older:
our filter, our ability to block out information decreases,
and the degree that it decreases directly correlates
with our inability to remember the things that we're trying to remember - our goals.
What happens in terms of multitasking?
Once again, the prefrontal cortex is in charge.
But here it's acting as a flight controller.
It's determining what information is the priority right now,
and through its connections with the back of the brain,
it's making decisions.
So, if you're crazy enough
to be riding a bike through Manhattan next to a cab, texting,
you have a lot of decisions to make.
So, maybe, the first decision is to focus on the traffic,
and then you think that it's safe enough to now continue your text message,
and so you do that.
But what you don't do is this: you don't split those decisions.
The prefrontal cortex has what's known as a central bottleneck.
And so what you do is switch.
Your prefrontal cortex switches between tasks
even though it feels like you're doing more than one thing.
This is what's led this being referred to as the myth of multitasking -
that you're not really doing more than one thing
unless they become very automated,
gum chewing, walking.
Although even those have been found to have some interference with each other,
believe it or not.
(Laughter)
With each switch, there is a time delay, and this leads to a cost -
an impact on performance.
You do not do two things as well as you do one thing
if you switch back and forth between them, and this gets worse as you get older.
We just had a paper published last week that shows that as you get older,
this switching, the letting go,
the disengaging and the reengaging become slower,
and this creates the interference in your memory.
Why do we do it?
We get the impression, and we have lots of data now,
that this is negative on our performance.
There is not a lot of data for this, some of this is anecdotal,
based on my impressions, but it's a resonable place to start.
Multitasking.
We have this sense it gives flexibility,
fresh perspective, increased variety,
it enables us to use downtime productively,
but probably the most salient aspect is that it's just more fun.
We are novelty seeking creatures.
It's a very strong part of our evolution to seek out new.
It stimulates the dopamine system, the reward system.
There is no doubt that one chunk of time in which you're multitasking
has more novelty than the same period of time in unitasking.
And so we probably seek it out.
There's even been a question that maybe it's even addicting at a certain level
when you're constantly pressured to get back into a new task
once you become used to it.
How about distraction? It's a little more complicated.
Why do people go into noisy coffee shops to read and to work?
Does anyone do that in this room?
Right, it's very common.
Usually you know which type of person you are.
So, it's something that's interesting - all this we're exploring in our lab now
to understand the driving force of this, and are there possible benefits?
So, what can be done about this?
It's just too dreary to say all these negative things
and then to walk off the stage.
So, we don't have all the answers,
but I can tell you it seems there are two paths,
at least to me:
we could change our behavior, or we could change our brains.
(Laughter)
Not necessarily in this scary way I'm depicting over here,
but in a positive way.
So, we could change our behavior because someone forces us to, right?
They say it's too dangerous to talk on the phone or to text while driving,
so we're not letting you do it anymore; we give you a ticket if you do that.
But there's other ways we can change our behavior
on things less dangerous to society.
So we could make decisions.
Just because we have all these wonderful technologies
doesn't mean we have to use it all at exactly the same time.
We get to make decisions based upon what we now understand
about how this interaction with technology and with ourselves
changes our behavior.
So I'm going to tell you what I do; I will not tell you what to do.
Since I've researched this,
I felt that I needed to make some decisions about my own behavior,
and this is what I decided:
When working on something very important,
something that demands high quality, especially something time sensitive,
I do one thing at a time, singular attention,
I quit my email - too distracting with messages coming in -
I turn off my phone,
I close my door, I do one thing, and I find it quite enjoyable.
I actually had stopped doing that for quite a while.
But I don't do this all the time.
There is many things in my day that are very boring,
I know they have to get done,
but I know if I try to do one thing at a time,
I would never finish it.
So I might set aside three hours of just intense multitasking;
the more I'm switching, the better; it just keeps it moving along.
So, it's not a message that technology is bad, don't do this.
It's just the point that decisions need to be made
when we interact and our environment changes.
It's happened many times in the past,
this is just another example that we have to learn how to deal with better.
Changing our brains.
Our brains are capable of a tremendous degree of plasticity.
That means it adapts and modifies to stimuli from the environment.
And we now know that this is not just when you're a child,
it occurs through your entire life.
We are looking at exercises - there's a video game that we developed in our lab
to see if we can strengthen these abilities through practice.
So, in this case, it's a car driving game and you're interacting with the road,
signs come up, sometimes relevant and sometimes irrelevant,
and you're pressing buttons, moving, challenging yourself
in an adaptive way, in a way that's fun.
What's interesting about this video game - it was designed to be played in our lab
while recording brain activity and seeing what's going on in our brain
while you interact with all this hype of interference.
We have a study going on now with healthy older adults,
they take home a laptop,
and they play this game at home, and while they play it,
their behavioral performance data downloads to their computer
and straight from Dropbox right into our lab,
almost in real time, we can get their brain data,
their behavioral data,
while they are playing at home.
Then they come into the lab and we look what's changed in their brain
to enable them to function at a higher level,
which is what we're seeing -
brains are capable of plasticity.
We're now looking at wireless EEG bluetooth headsets
that allow us to have our older participants put these on at home
and record their brain activity,
so we could move our lab outside of our laboratory into people's homes
and record what are the changes in the brain
that lead to this higher ability with practice.
And then they can come back into the lab,
and we can use fMRI to look at these changes in networks.
I think it's an exciting time where we're learning more
about how our brains can adapt to this.
So with that, I want to thank you for your attention
and, of course, your lack of attention to other things.
(Applause)