Transcriber: Jessica Lee
Reviewer: Denise RQ
00:00
So how do we learn?
00:14
And why does some of us learn things
more easily than others?
00:16
So, as I just mentioned,
I'm Dr. Lara Boyd.
00:21
I am a brain researcher here
at the University of British Columbia.
00:24
These are the questions that fascinate me.
00:28
(Cheers) (Applause)
00:31
So brain research
is one of the great frontiers
00:35
in the understanding of human physiology,
00:38
and also in the consideration
of what makes us who we are.
00:41
It's an amazing time
to be a brain researcher,
00:45
and I would argue to you
00:47
that I have the most interesting job
in the world.
00:49
What we know about the brain
is changing at a breathtaking pace.
00:52
And much of what we thought we knew
and understood about the brain
00:56
turns out to be not true or incomplete.
00:59
Some of these misconceptions
are more obvious than others.
01:03
For example, we used to think
01:06
that after childhood the brain did not,
really could not change.
01:09
And it turns out that nothing
could be farther from the truth.
01:14
Another misconception about the brain
01:18
is that you only use parts of it
at any given time
01:19
and it's silent when you do nothing.
01:23
Well, this is also untrue.
01:25
It turns out
that even when you're at a rest
01:27
and thinking of nothing,
your brain is highly active.
01:29
So it's been advances
in technology, such as MRI,
01:33
that's allowed us to make these
and many other important discoveries.
01:37
And perhaps the most exciting,
01:40
the most interesting
and transformative of these discoveries
01:42
is that, every time you learn
a new fact or skill,
01:45
you change your brain.
01:49
It's something we call neuroplasticity.
01:51
So as little as 25 years ago,
we thought that after about puberty,
01:54
the only changes that took place
in the brain were negative:
01:58
the loss of brain cells with aging,
02:01
the result of damage, like a stroke.
02:03
And then, studies began
to show remarkable amounts
02:06
of reorganization in the adult brain.
02:09
And the ensuing research has shown us
02:13
that all of our behaviors
change our brain.
02:15
That these changes are not limited by age,
02:19
it's a good news right?
02:23
And in fact,
they are taking place all the time.
02:24
And very importantly,
02:27
brain reorganization helps
to support recovery
02:29
after you damage your brain.
02:32
The key to each of these changes
is neuroplasticity.
02:34
So what does it look like?
02:39
So your brain can change
in three very basic ways
02:41
to support learning.
02:44
And the first is chemical.
02:45
So your brain actually functions
by transferring chemicals signals
02:48
between brain cells,
what we call neurons,
02:51
and this triggered a series
of actions and reactions.
02:53
So to support learning,
your brain can increase the amount
02:57
or the concentrations
of these chemical signaling
03:00
that's taking place between neurons.
03:03
Because this change can happen rapidly,
03:06
this supports short-term memory
03:09
or the short-term improvement
in the performance of a motor skill.
03:10
The second way that the brain
can change to support learning
03:15
is by altering its structure.
03:18
So during learning, the brain can change
the connections between neurons.
03:21
Here, the physical structure
of the brain is actually changing
03:25
so this takes a bit more time.
03:28
These type of changes are related
to long-term memory,
03:30
the long-term improvement
in a motor skill.
03:33
These processes interact,
and let me give you an example of how.
03:37
We've all tried to learn
a new motor skill,
03:41
maybe playing the piano,
03:44
maybe learning to juggle.
03:46
You've had the experience
of getting better and better
03:48
within a single session of practice,
03:50
and thinking "I have got it."
03:53
And then, maybe you return the next day,
03:55
and all those improvements
from the day before are lost.
03:57
Well, in the short-term,
your brain was able to increase
04:02
the chemical signaling
between your neurons.
04:05
But for some reason, those changes
did not induce the structural changes
04:08
that are necessary
to support long-term memory.
04:13
Remember that
long-term memories take time.
04:17
And what you see in the short term
does not reflect learning,
04:20
It's these physical changes
04:23
that are now going to support
long-term memories,
04:25
and chemical changes
that support short-term memories.
04:27
Structural changes also can lead
to integrated networks of brain regions
04:32
that function together
to support learning.
04:36
And they can also lead
to certain brain regions
04:39
that are important
for very specific behaviors
04:41
to change your structure or to enlarge.
04:44
So here's some examples of that.
04:46
People who read Braille
04:49
have larger hand sensory areas
in their brain than those of us who don't.
04:51
Your dominant hand motor region,
which is on the left side of your brain,
04:56
if you are right-handed,
is larger than the other side.
05:00
And research shows
the London taxi cab drivers
05:04
who actually have to memorize a map
of London to get their taxi cab license,
05:07
they have larger brain regions devoted
to spatial, or mapping memories.
05:12
The last way that your brain
can change to support learning
05:17
is by altering its function.
05:20
As you use a brain region,
05:23
It becomes more and more excitable
and easy to use again.
05:25
And as your brain has these areas
that increase their excitability,
05:29
the brain shifts
how and when they are activated.
05:32
With learning, we see
05:35
that whole networks of brain activity
are shifting and changing.
05:37
So neuroplasticity is supported
05:42
by chemical, by structural,
and by functional changes,
05:44
and these are happening
across the whole brain.
05:48
They can occur in isolation
from one or another,
05:51
but most often,
they take place in concert.
05:53
Together, they support learning.
05:57
And they're taking place all the time.
05:59
I just told you really
how awesomely neuroplastic your brain is.
06:04
Why can't you learn anything
you choose to with ease?
06:08
Why do our kids sometimes fail in school?
06:13
Why as we age
do we tend to forget things?
06:16
And why don't people fully recover
from brain damage?
06:20
That is: what is it that limits
and facilitates neuroplasticity?
06:23
And so this is what I study.
06:29
I study specifically how it relates
to recovery from stroke.
06:31
Recently, stroke dropped
06:35
from being the third leading cause
of death in the United States
06:36
to be the forth leading cause
of death.
06:40
But actually, it turns out
06:44
that the number of people
having a stroke has not declined.
06:46
We are just better at keeping
people alive after a severe stroke.
06:49
It turns out to be very difficult
to help the brain recover from stroke.
06:53
we have failed to develop
effective rehabilitation interventions.
06:59
The net result of this
is that stroke is the leading cause
07:05
of long-term disability
in adults in the world;
07:09
individuals with stroke are younger
07:13
and tending to live longer
with that disability,
07:15
and research from my group actually shows
07:18
that the health-related quality of life
of Canadians with stroke has declined.
07:21
So clearly we need to be better
07:26
at helping people recover from stroke.
07:28
This is an enormous societal problem,
07:30
and it's one that we are not solving.
07:33
So what can be done?
07:36
One thing is absolutely clear:
07:38
the best driver of neuroplastic change
in your brain is your behavior.
07:41
The problem is that the dose
of behavior, the dose of practice
07:46
that's required to learn
new and relearn old motor skills,
07:50
And how to effectively deliver
these large doses of practice
07:55
is a very difficult problem;
It's also a very expensive problem.
07:58
So the approach
that my research has taken
08:03
is to develop therapies that prime
or that prepare the brain to learn.
08:05
And these have included brain simulation,
exercise, and robotics.
08:09
But through my research,
I've realized that a major limitation
08:14
to the development of therapies
that speed recovery from stroke
08:18
is that patterns of neuroplasticity
are highly variable from person to person.
08:21
As a researcher,
variability used to drive me crazy.
08:28
It makes it very difficult
to use the statistics
08:32
to test your data and your ideas.
08:35
And because of this,
medical intervention studies are
08:38
specifically designed
to minimize variability.
08:41
But in my research,
it's becoming really clear
08:45
that the most important,
the most informative data we collect
08:48
is showing this variability.
08:52
So by studying the brain
after stroke, we've learned a lot,
08:56
and I think these lessons
are very valuable in other areas.
09:00
The first lesson is
09:06
that the primary driver of change
in your brain is your behavior,
09:07
so there is no neuroplasticity drug
you can take.
09:11
Nothing is more effective than practice
at helping you learn,
09:15
and the bottom line
is you have to do the work.
09:19
And in fact, my research has shown
09:23
increased difficulty, increased struggle
if you will, during practice,
09:25
actually leads to both more learning,
09:30
and greater structural change
in the brain.
09:32
The problem here is that neuroplastcity
can work both ways.
09:37
It can be positive,
you learn something new,
09:42
and you refine a motor skill.
09:45
And it also can be negative though,
you forgot something you once knew,
09:47
you become addicted to drugs,
09:51
maybe you have chronic pain.
09:53
So your brain is tremendously plastic,
09:56
and it's been shaped both structurally
and functionally by everything you do,
09:58
but also by everything that you don't do.
10:03
The second lesson
we've learned about the brain
10:07
is that there is
no one-size-fits-all approach to learning.
10:09
So there is no recipe for learning.
10:14
Consider the popular belief
that it takes 10,000 hours of practice
10:16
to learn and to master a new motor skill.
10:20
I can assure you
it's not quite that simple.
10:23
it's going to take a lot more practice,
and for others it may take far less.
10:28
So the shaping of our plastic brains
is far too unique
10:32
for there to be any single intervention
that's going to work for all of us.
10:36
This realization has forced us to consider
something call personalized medicine.
10:41
This is the idea that to optimize outcomes
10:46
each individual requires
their own intervention.
10:49
And the idea actually comes
from cancer treatments.
10:53
And here it turns out that genetics
are very important in matching
10:55
certain types of chemotherapy
with specific forms of cancer.
10:59
My research is showing that this
also applies to recovery from stroke.
11:04
There're certain characteristics
of brain structure and function
11:08
we called biomarkers.
11:11
And these biomarkers
are proving to be very helpful
11:12
and helping us to match
11:15
specific therapies
with individual patients.
11:17
The data from my lab suggests
it's a combination of biomarkers
11:20
that best predicts neuroplastic change
and patterns of recovery after stroke.
11:24
And that's not surprising, given
how complicated the human brain is.
11:29
But I also think we can consider
this concept much more broadly.
11:34
Given the unique structure
and function of each of our brains
11:39
what we've learned about neuroplasticity
after stroke applies to everyone.
11:43
Behaviors that you employ
in your everyday life are important.
11:50
Each of them is changing your brain.
11:54
And I believe we have to consider
11:57
not just personalized medicine
but personalized learning.
11:59
The uniqueness
of your brain will affect you
12:03
both as a learner and also as a teacher.
12:05
This idea helps us to understand
12:08
why some children can thrive
in tradition education settings
12:11
why some of us can learn languages easily
12:17
and yet, others can pick up
any sport and excel.
12:19
So when you leave this room today,
12:25
your brain will not be the same
as when you entered this morning.
12:28
And I think that's pretty amazing.
12:32
But each of you is going to have changed
your brain differently.
12:36
Understanding these differences,
12:40
these individual patterns,
this variability and change
12:42
is going to enable
the next great advance in neuroscience;
12:46
it's going to allow us to develop
new and more effective interventions,
12:49
and allow for matches
between learners and teachers,
12:53
and patients and interventions.
12:57
And this does not just apply
the recovery from stroke,
13:00
it applies to each of us, as a parent,
as a teacher, as a manager,
13:03
and also because you are
at TEDx today, as a lifelong learner.
13:08
Study how and what you learn best.
13:13
Repeat those behaviors
that are healthy for your brain,
13:16
and break those behaviors
and habits that are not.
13:20
Learning is about doing the work
that your brain requires.
13:26
So the best strategies
are going to vary between individuals.
13:30
You know what, they're even going
to vary within individuals.
13:34
So for you, learning music
may come very easily,
13:37
but learning to snowboard, much harder.
13:40
I hope that you leave today
13:44
with a new appreciation
of how magnificent your brain is.
13:46
You and your plastic brain are constantly
being shaped by the world around you.
13:49
Understand that everything you do,
13:54
everything you encounter, and everything
you experience is changing your brain.
13:57
And that can be for better,
but it can also be for worse.
14:01
So when you leave today,
go out and build the brain you want.
14:05
Thank you very much.
14:10