Horizon (1964–…): Season 48, Episode 11 - Out of Control? - full transcript

We like to believe we're in control
of everything we do,

everything we think
and everything we feel.

But scientists are discovering
that at every moment of our lives,

an unseen presence
is guiding us all.

Now, they're exploring the secret
world of your unconscious mind.

It's why we feel a certain way,
why we think a certain way,

it's why we are the way we are.

Long associated with dark desires,

the real nature of the unconscious
is becoming clear.

The unconscious, it's not
a primal, unruly, animal thing.

It's, in fact, one of the most
sophisticated things we have.



New experiments are now revealing
that what you think you do

and what you really do
can be very different.

Most of the time
we're on cruise control.

From what you eat
to who you love,

your unconscious can actually
call the shots.

And because it is so powerful,

scientists are finding ways
to harness its hidden potential.

If you think that the internet and
Facebook have caused a revolution,

wait until you see what happens when
we really understand the human brain.

If you think you're really
in control of your life,

you may have to think again.

A normal street in a normal town.

But there's more here
than meets the eye.

Each day, life whirls around you
in a hectic blur.



So just stop.

Take a moment.

Have a proper look around.

It really is a busy,
cluttered world out there.

How much of all this
are you actually aware of?

Scientists are trying to find out.

They're investigating the limits
of how much anyone
can consciously take in at once.

We have a sense of seeing
this continuous world

that's unravelling continuously
around us.

And that's probably not what we're
picking up from the world at all.

For example, we move our eyes
about five times a second -

incredibly rapid eye movements.

It's probably the fastest movements
that our bodies can make,

these ballistic eye movements.

What we're really doing
is taking snapshots
every time we glance at something

and in between, where the world
would be whizzing by our retinas,
we're blind.

And then if we look within
a given snapshot,

you think, at least within a
given snapshot this is the world
and I sense it,

but when we try to get down
and measure what a person actually
takes in in any given glance,

it's hard to estimate.

Finding out how much someone
can take in from the snapshot

of a single glance
can reveal their brain's ability.

OK, George, do you want to
take a seat? Yeah.

It's a subject being studied
in the University of Oxford's
Brain and Cognition Laboratory.

We're going to try not to squish
your head

so let me know when you touch.

Graduate student George
is today's guinea pig.

I think you're there, yeah.

I'm also going to give you
this fibre optic response pad.

OK.

Using these four shapes on screen,

today's test will find out how much
George can consciously take in.

He'll have 200 milliseconds,
the duration of single glance,

to remember the shapes' positions.

Just one will then reappear

but its orientation has changed.

George's task,
based on that brief glimpse,

is to choose whether it's been
rotated left or right.

This is how it first appeared.

In this case,
it was rotated to the right.

By doing this,
we'll be able to compute
how many of these four objects

he was actually able to hold
in his mind.

Try it yourself.

Remember, you have to decide
whether the object that reappears

has rotated left or right
from its original position.

Left.

Try again.

Left again.

Not easy, is it?

Most of us would probably think
before an experiment like that

that any one of us can hold four
simple coloured shapes in mind

and be able to respond about them
after a second.

In fact, we see that
not to be the case.

George had to hold in mind
the position of just four shapes.

He couldn't do it.
He couldn't even manage three.

Averaged over the test,
he remembered 2.8.

This figure represents
the approximate number of things

that George's brain can consciously
deal with at any one time.

And this result is typical
for everyone.

This simple screen contains
more things

than you can consciously handle.

Your conscious mind can cope
with no more than two or three
tasks at once.

So it just shows us how amazingly
limited our perceptual awareness is

even once we've stripped down
the world to, you know,
an absurd level.

So take another look around.

Even now, there's more going on
than you can consciously take in.

The sense that you're aware of
everything occurring around you

is nothing more than one of life's
greatest illusions.

But if your conscious mind can deal
with only a fraction of the things
that happen to you each day,

something else must be responsible
for all the rest.

And this is where the hidden
processes

of your unconscious
mind come in.

Often associated with dreams
and repressed desires,

the unconscious is now starting
to reveal its true power.

But how big a role do scientists
think it plays in your life?

Imagine that sheet of paper
represents everything
the brain can do,

how much do you think is conscious
and how much is unconscious?

Wow. That's an interesting question.

How much is conscious
and how much is not conscious?

You're not serious.

You are?

Now that's a very tricky thing
to do.

That is very interesting.

I guess, if I had to guess...

..I would say that if this
is everything the brain can do...

..about this much...

is conscious.

Erm, I would say maybe
something like that.

Out of the whole bit of paper.

I would say about this much
is conscious.

So if this whole sheet of paper
was...? OK.

I will probably draw something
small in the middle like that

to represent the conscious bit.

That's my...guess.

I have no idea.

Scientists agree that the role
played by your conscious mind

is much smaller than
previously thought...

..which raises a puzzling question.

Are you in control
of your unconscious

or is it in control of you?

To find out, scientists
need to reveal the strategies
it uses to guide you.

The problem is, unconscious
strategies are shrouded in secrecy.

Here in Ohio, Dr Dennis Shaffer
is attempting to reveal them

in an unusual experiment.

He has spent his career
investigating the hidden workings
of the unconscious mind.

The strategies that are used
by the brain,

we're typically not consciously
aware of.

There's a huge discrepancy between
the strategies that we use

and, kind of, our conscious
expectations of those.

These volunteers don't realise it,

but Dennis will be comparing
what they consciously think they do

with the real strategies at work
in their unconscious minds.

And, to do it, he'll be using...

..this.

What you're going to be doing today
is chasing this toy helicopter.

We're going to put this video camera
over your head

so we get the perspective
of what you're seeing.

Each participant believes they
have their own personal strategy
for catching the helicopter.

The question is, is this what's
really going on in their heads?

First up, Trish.
Her strategy is speed.

As far as key strategy,
I'd say you've got to focus on

keeping your eye on the helicopter
and keeping a steady speed.

Next up, Sid. His strategy
is all about positioning.

My strategy's to make sure
each time it moves,

I move just as quickly
to stay below the helicopter.

For Keith, it's all about angles.

You've got to get it
right on its angle of approach
towards the ground,

looking at the whole line of the arc.

So do these personal strategies
represent what's actually happening
in their unconscious minds?

Dennis now has enough head
camera footage to find out.

So what we're doing is identifying
where the helicopter is positioned

relative to the background scenery
from the pursuer's perspective.

Having chosen a background
point for reference,

Dennis marks
the helicopter's position

and then advances the video
a few frames.

The helicopter's new position
is now recorded.

The process is repeated,

gradually mapping what the flight
path of the helicopter

looked like to the pursuer
throughout the entire pursuit.

Despite the random path
taken by the helicopter,

a pattern soon begins to emerge.

What this shows is that
what the pursuers are doing
is moving in such a way

so as to keep the toy helicopter
appearing to move

relative to the background scenery
in a straight line.

Remarkably, the exact same results
are seen in every single person,

regardless of the apparent
chaos of their pursuit.

As the helicopter moved,
each of them adjusted their position

so that, to them, it appeared
to fly in a straight line

against the background scenery.

'From an outside appearance they may
be running in different paths,

'but the one constant is that
they keep the toy helicopter

'appearing to move
in a straight line.'

A beautifully simple,
unconscious algorithm

hardwired into the head
of every pursuer

is responsible for getting
them to the right spot.

THEY APPLAUD AND WHISTLE

This is not something that they're
consciously aware that they're doing.

It's all about patience.

And you can demonstrate that
just by asking them how they do it.

Keeping a steady speed.

And it's not going to match up
to this at all.

Go criss-cross, feet over feet.

So, although you might think you're
conscious of everything you do,

this experiment reveals that your
unconscious is often in control...

employing its own rapid,
efficient strategies

to guide your every step
through life.

But how does your unconscious make
these split-second decisions?

For scientists,
it's a complex question.

So, for help,
they're turning to creatures

that might display
the same characteristics

as the neurons which
make up the brain.

Rock ants.

At little over 2mm long, rock ants
don't amount to much on their own

but their collective
decision-making behaviour

is providing insights into
the sophisticated way

that your unconscious
mind might work.

What we can do with these ants is...

we can hold an entire ant colony
in a small Petri dish, like this,

and we can think of each individual
worker as an excitable,
activatable unit

and that has a parallel
with neurons in our brains,

that are units that
are wired together

that get more and more
excited and can excite one another.

But studying the similarities
between ant decision-making

and the workings of the brain
is no easy job.

To do this, ants need
to be identifiable...

..and that means each one
needs to be given

a microscopic radio
tag "rucksack".

It's is an intricate task.

Each ant is anaesthetised before
the radio tag is glued to its back.

These transmitters,
just half a millimetre across,

will allow each ant to be tracked.

Tagging complete, the entire
colony is now presented with
a momentous decision -

choosing a new home.

Right, so what we have
to do is bring in the colony

that is going to have
to make the decision

and they've been living very nicely
in this microscope slide nest

and essentially what we're going to
do is be a little bit beastly to them

but not too much, we're going
to actually have to

destroy this nest
by taking off the roof.

So, in a flash, this colony
will be homeless

and they'll have to find a new nest.

So, there I go...

..and all of a sudden
there are draughts racing in there

and they, you know, howling gales

from the perspective
of an individual ant,

and they're spilling out
in all directions,

looking for a new place to live.

The ants' search will take them
to the other end of the arena,

where Professor Franks has placed
two alternative new homes.

Each has a laser radio tag reader
over the door

to monitor which ants visit.

But the similarities end here.

The left-hand nest is darker -
a more likely choice for the ants.

So, we're trying to give them
a very obvious and simple choice

between a really good nest
and a rather mediocre one

and we'll see how they perform.

It doesn't take long for individual
ants to discover particular nests,

but how do they collectively
decide which is best?

The colony's dilemma represents the
instinctive, split-second choices

which your unconscious
faces each day.

To solve the problem,

the ants now start working
together democratically,

just like neurons,

to reach a consensus on the best
possible decision.

If an ant likes what it finds,

it returns to the old nest
to recruit a follower,

which it leads back
to the new site.

Here, the second ant will conduct
its own independent survey.

So, basically, you've got two
populations that are being recruited,

one to this particular nest

and the other population
to the alternative.

As the experiment progresses,

the population of ants in favour
of the darker nest snowballs.

By sharing information, the ants
are building up a group picture

of their surrounding environment.

Soon they're finding so many
other ants in the darker nest

that they pass a threshold,
the quorum threshold,

and the group decides that this
must be the best choice.

This will be their new home.

When it comes to decision-making,
the wisdom of the crowd prevails.

In ant colony and brain,
it's a wonderfully efficient system.

In both systems, you can
have these populations

growing up to a particular
threshold,

a sort of quorum threshold, if
you will, where it's a tipping point,

where the whole system will change
from one behaviour to another.

Most remarkably of all,
both systems can vary the threshold

based on the urgency
of the decision.

'The quorum isn't fixed,
it's beautifully flexible,

'they can lower the threshold
in an emergency'

or they can raise the threshold
when they've got all the time
in the world,

it's a beautiful
decision-making system.

This ability to weigh up
the pros and cons

as everything changes around you

is one of your unconscious mind's
most vital skills.

Yet even this only scratches the
surface of how it shapes your life.

Because every day your unconscious
can resort to the slyest of tricks.

Wherever life takes you,

your unconscious will be subtly
shaping the illusion that
you call reality.

Take a place like this,
a world of temptation.

Now you know that life's little
luxuries come with a health warning

but chances are you indulge anyway,

all the while remaining optimistic
about your future well-being.

Dr Tali Sharot wants to know why.

'Think, for example, about eating
food that's not good for you,'

like these lovely cupcakes,
or smoking, or unprotected sex.

All of these examples are examples
in which people act in a way

that's maybe rewarding
for them at present

but can be very harmful
in the future.

It seems we're all optimists.

Despite the risks,
we just carry on anyway.

From health to finance,
to how we drive,

negative information
doesn't really sink in.

'We go through life experiencing
heartache and failure'

but still we remain optimistic
and that's a great puzzle.

How is it that we remain
optimistic in the face of reality?

To find out why takes scientists
deep into the machinery of the mind.

And finally, I'm going
to put this on top...

Today, Tali is using a brain scanner

to find out why we ignore so much
of the negative information
that comes our way.

OK, Tom, so, we're about to start
the experiment now.

To do this, she'll be asking
volunteer Tom

to predict his chances
of experiencing

a selection of 80 different
negative events in the future.

So, we're recording Tom's brain
activity and what you can see here

is actually what Tom is looking at
in the scanner, through his mirror.

For example, he will
see the word "cancer",

and then he will have to
estimate how likely it is

that he will suffer from cancer
in his lifetime.

Tom reckons his chance of cancer
is 18% and types it in.

OK, so, now, we're going to show
him the average likelihood

of suffering from cancer, which
is about 30% in the Western world.

Tom has a moment to realise
that he's underestimated
his chance of cancer -

he's been too optimistic.

He's then presented with the next
of the 80 negative events.

With each one,
he again gives his prediction

before finding out
the real statistic.

When he reaches the last
of the 80 events,

the same list is repeated and he has
to predict his chances again.

'And what we're interested in,'

is whether Tom is going to use
information that we gave him,

in order to change his beliefs.

Each time this experiment
is performed,

the results are most surprising.

So what we found was that
when you give people positive
information about the future,

for example, you tell them

that their likelihood of suffering
from Alzheimer's is lower

than what they thought,
they take on board the information.

We all tend to update
our views about the future

when we receive new information
suggesting things will turn out
better for us than we thought.

'However, when you give people'

negative information
about the future,

for example, if they believe that
their chances of suffering from
Alzheimer's is only two percent

and we tell them, well, the average
is much higher than that,

for example, it's ten percent,
so this is negative information,

they don't change their beliefs

and they stick to this very
optimistic view of the world.

The scans show that
the part of the brain

that considers negative
information about the future

seems to malfunction.

The part that deals
with positive information

appears much more active.

It suggests that your brain wilfully
ignores negative things

and maintains a rose-tinted
and inaccurate view of
the world instead.

It looks like the brain is not
doing what it's supposed
to be doing

but the reason that
our brain tricks us

is because if we expect positive
events in our future,

stress and anxiety is reduced
and that's good for our health.

And there's another reason too.

'I think if we expect to get ahead,
if you expect the gold medal,'

that motivates you to put
in the effort to train,

'you know, for four years before
the Olympics, for example.

'So, you might, at the end,
not get the golden medal'

but the idea is that you need to
expect the gold medal

in order to get the silver.

'And so it acts as a motivation.

'And that's why, I think, the brain
has evolved to become optimistic.'

This in-built tendency
to optimistically ignore
starkly obvious risks

has been essential to our
success as a species.

If you think about things such
as our ancestors deciding to go

out of Africa and exploring
the rest of the world,

in order to explore something new,

you have to imagine that there is
something out there for you to find.

Something novel, and something
better than what you have now

because otherwise there is no need
to go and discover other
parts of the world,

or even other parts of the universe.

This is one of the most ingenious
tricks of the unconscious.

By making you view the world
through rose-tinted glasses,

it keeps you striving
for a better future.

Taken together, the latest
discoveries are starting to reveal

that the sense you're consciously in
control of everything you do

is just an illusion.

It's a sophisticated and intricate
one but it's no luxury,

it's a necessity

because your very survival has long
depended upon everything

that your unconscious does
for you behind the scenes.

It's something that scientists
are investigating in Oxford.

Taking part is GY, a volunteer who
wishes to stay anonymous.

When he was young,
his visual cortex,

the part of the brain
that deals with vision,

was damaged in an accident.

In both eyes he's partly blind.

He's able to see only to the left,
not the right.

'I don't actually see
anything in my blind field.

'It's a very strange phenomena.'

Yet today's experiment will attempt
to show something remarkable

that, in the areas where he's blind,

GY is somehow, instinctively,
able to see.

What I'm going to do is
to present a stimulus

moving upwards or downwards
in GY's blind field

and I'm simply going
to ask him to indicate

whether the stimulus moves
up or down.

'Now, this is a stimulus
which he's unable to see.'

Ready? Yep.

Up.

Down.

Although GY can't consciously
see the moving shape,

he is required to guess
which way it moves.

Up.

Down.

After a number of trials, some
compelling results come through.

He was right on 37 out of 40
trials in that run,

which is an extremely
significant result.

Erm, so what this shows is that,

despite the fact that
he's clinically blind,

he's capable of discriminating
the direction of motion

of something that's moving
in his blind field.

Remarkable.

This ability is known as blindsight.

I don't actually see
anything move at all,

it's just an awareness of movement

and I can detect
the direction it goes in.

That sounds really weird,
doesn't it?

Somehow, GY experiences movement,

even though he can't properly
see it himself.

I always refer to it
as a "visual experience,"

but I don't actually see anything.

Just, I know something and I don't
know what, has gone up or down.

So where does GY's
blindsight stem from

and why does this ability exist?

It all comes down to the remarkable
construction of the brain itself.

With one hundred billion neurons
connected by over

one hundred trillion synapses,

the human brain is immensely
complicated.

So this is what a human
brain looks like.

This is the front, this is
the back, two cerebral hemispheres.

And if we want to understand
what's going on in blindsight,

I need to show you a specimen
that's been dissected already.

And this is the inner
surface of the hemisphere.

And this region here is
the primary visual cortex,

which is the area that's
damaged in blindsight.

By interpreting signals
flowing from the eyes,

the visual cortex allows us
to see the outside world.

If it's damaged, like in GY,
these signals aren't registered,

even if the eyes are still working.

But there is another, older,
visual pathway from eyes to brain.

As it turns out, only about
90 percent of the fibres

leaving the eye terminate
in the primary visual cortex.

The remainder of the fibres

head off to other
centres in the brain.

Most important of these is
the superior colliculus,

which you can see just here.

Its name belies its size.

In humans, the superior
colliculus might be tiny.

But in evolutionary terms,
it's always been vital.

In many other creatures it's one
of the brain's biggest structures,

geared to rapidly orienting
the eyes toward sudden movements.

This evolutionary remnant

is where GY's blindsight
is thought to come from.

Despite not being able to
properly see,

he retains a primal awareness of
sudden movements,

a sense that something is there.

We need to not only be able
to identify

what's out there in the visual scene,
but where they are.

Because in the case of a predator,

ultimately we need to take
evasive action.

GY's blindsight helps to show

that in the human brain's
long history,

the unconscious preceded
the conscious mind,

but it wasn't replaced by it.

It's still there today,
hidden from view,

but still on the lookout for danger.

But there's another thing that the
unconscious does for you each day.

Take all those complex skills
you've perfected in life.

The truth is that once you've got
the hang of them,

you barely have to
concentrate on them at all.

They've become automatic,
and unconsciously controlled.

How this happens is one
of neuroscience's biggest mysteries.

And the place to solve it is here.

The problem for
Professor Julien Doyon

is that little of what you learn in
life can be done in a brain scanner.

Obviously you have
only 60 centimetres in the scanner,

and so it's very difficult to study
motor movements,

for example, movements like in golf
or a tennis movement,

one cannot do that in the scanner.

The changes that happen
inside your brain as you learn new,

automatic skills, are clearly
not easy to study.

But a chance conversation with
an old friend led Julien

to a most unusual solution -

knitting.

At the time, we were actually
carrying on a conversation

like this, and he saw me knitting.

'I said to her,'

"It looks like this movement is
completely automatic for you.

"You basically do your movements
and you're able to talk."

And then he said, "Oh, this would
be a great activity to use,

"but if you were in the scanner,
you'd have to lie there,

"very, very still, not move
your shoulders and knit

"lying on your back.
Can people do that?"

And I said, "Well, any knitter
who's automatic can do that!"

But simply seeing into the mind
of an experienced knitter wasn't

enough to reveal how the process
of learning a new skill occurs.

What Julien needed was
a way of comparing how the brain

performs automatically with how it
works when it's starting to learn.

It was a rather tricky task.

'But then Rhonda told me something
very important, she said,

'"There are two approaches to knit,'

"and if I try to knit with
this other approach,

"this other technique, that
would be like starting again,

"I would need to think about the
movements that I have to make,

"and learn from scratch."

For Julien, this was a revelation.

And so began
one of the most

colourful experiments
in neuroscience history.

Today, Julien will be scanning
Rhonda's brain as she knits.

So Julien's going to give
you the needles...

She will start with the style
of knitting she's been doing

since she was a child,

and which is now completely
automated in her unconscious mind.

We're all ready to start,
we're going to go to the other side.

OK, Rhonda. How are you?

'I'm fine, very relaxed.'

OK, I'm going to ask you
to produce

knitting movements for
about 30 seconds.

OK, here we go...

So, here Rhonda is producing
movements which she has been

practising for years that
are completely automatic for her.

Data soon starts appearing
on screen.

And we can see that there is
a lot of activity in the striatum.

As Rhonda knits, the striatum,
deep in the brain,

coordinates her complex
automated movements.

It's a wonderfully
streamlined process.

But what the team wants to see
is what happens

when the learning process begins.

If we were then asking her
to do the knitting

with a technique that she's not
familiar with then we'd see

perhaps a very different
pattern of activity.

The team now runs the test
one more time.

All right? 'All right.' Here we go.

OK, so we're starting to
see some activity

in the primary motor cortex.

And you're starting to see
some activity

in both sides of the cerebellum,
as well.

We think that those regions
at the beginning are important

to try to figure out what's the best
way to produce movements.

When you learn a skill,
from knitting to juggling,

multiple parts of your brain,
especially the cerebellum,

work hard to coordinate
your new movements.

But as you practise,
something profound occurs.

The architecture of your brain
starts to change.

New, efficient neural networks form,
a process known as plasticity.

It's one of neuroscience's
biggest discoveries.

So, while you might find the process
of learning hard, with perseverance,

your unconscious mind will rewire
itself to share the load.

When the movements are completely
automatic, it allows us

to free up our attentional
demands for other activities.

And so now we can pay attention to
other things that we want

to do in life.

By automating complex
actions like this, your unconscious

frees your conscious mind,
and makes you who you are.

The discovery of plasticity
represents a new era

in our understanding
of the human brain.

It reveals the power
of the unconscious to adapt

and form new connections.

But scientists are wondering whether
this power can get out of control.

It's something that
doctors are researching

in a rather pleasant
and exclusive laboratory.

One of America's finest
golf courses, here in Arizona.

They're studying the curse of many
experienced golfers...

the yips.

The yips is a symptom which
golfers describe in which

they get a twisting, a twitching,
a jerking movement during

the time of putting, and less
than a second before actually

striking the ball,
the involuntary movement occurs.

This uncontrollable twitch can stop
the most experienced players

sinking the simplest putts.

Expert golfer Tom Wilcox
knows this only too well.

I've been a golf
professional for 40 years

and it certainly has been
a problem in competitive situations

because when you get the yips,
you literally

can feel a little
jerk in your hands,

and you can feel it affect
the blade of the putter,

and the ball goes off line,
or goes too far,

or doesn't go far enough,
so obviously that's more strokes,

and they pay money for low scores,
not for high scores in golf.

For years, the yips has been
thought of simply

as golfers crumbling under pressure.

But Dr Adler suspects that there
might be more to it

than choking in the
heat of competition.

His research here has taken him

deep into the mysterious
workings of the brain itself.

Make a muscle. OK.

Today, Dr Adler and
his assistant, Luann,

are attempting to see if the yips
might be caused

by the brain getting out of control.

We're going to record from
wrist flexor, extensor, bicep,

tricep and deltoid.

First they wire up Tom,
to monitor the messages his muscles

receive from his brain.

I'll be a bionic golfer, right?

They're looking for
a tell-tale signal

which might reveal the problem.

What I would like you to do
is slip on this CyberGlove.

Last on is a sophisticated glove
which will record

Tom's exact wrist movements
as he putts.

And what it does is,
it allows us to measure movement

at all of the different joints,
to look at what happens

to finger movements and hand
movements during the putting stroke.

It's, er, not exactly how
I normally dress for golf,

so I suspect that this is
going to be an interesting

feeling when I get to putting.

The glove shows Tom's exact
hand position,

it will reveal any twitches
as he putts.

Good, and move the wrist.

Perfect.

For the next half-hour,
Tom putts repetitively,

to build a picture of the signals
flowing from his brain.

It's an elusive little thing,
isn't it?

Oh, God!

Do you feel anything?
I did that one.

Often, as Tom attempts
to make a putt,

there is a distinct
twitch in his wrist.

That was nasty.

This research is only new,
but the hypothesis,

based on evidence from other
studies, is that in some golfers,

the yips may be caused by faulty
wiring in the brain.

The suggestion is that the neural
networks which form during

the initial process of learning new
skills can start to go wrong.

The result?

A condition known as
a focal dystonia,

in which the rogue brain connections
cause involuntary movements,

a bit like Tom's twitch.

There may be some abnormal wiring
within the brain,

in which the brain is perceiving
things differently

than one would normally perceive,
and causing muscles

to contract involuntarily.

The unconscious, it seems,
doesn't always behave itself.

But as scientists begin to
understand how it works,

they're starting to wonder whether
it's possible to rewire it

and solve the problem.

Guitarist Douglas Rogers hopes so.

In the 1970s, he was one of
Britain's top classical guitarists,

playing concerts worldwide.

But like golfers with the yips,

he began experiencing involuntary,
unconsciously-controlled

hand movements
which derailed his career.

I missed the first finger,
there...

To solve this problem,

he's come to
University College London

to try a radical new treatment.

It seems to get more
and more unreliable...

Dr Mark Edwards, an expert
in movement disorders,

is going to try treating Douglas,
by attempting to access

the hidden depths of
Douglas's brain.

So everything's a mess...

When you make a movement,

the brain usually activates
one muscle

and actively turns off other
muscles,

that's why we can make
very precise movements,

that's something called
surround inhibition,

it's a very useful
thing for everybody,

but particularly for playing
a musical instrument.

And we know that that process
seems to go wrong

in people with hand dystonia.

So what we're going
to try and do

is to deliberately turn up this
mechanism in the brain,

that should inhibit movements
that you don't want.

To do this, the team attempts to
teach Douglas's brain

how to increase the inhibition
signal it sends to his hand

as he performs a simple task
just pushing a button.

When he moves, a device
resting against his hand vibrates.

So what we're doing now is
giving some vibration

to a surround muscle,
so it's like boosting

the error signal to the brain,
saying,

"Look, this muscle is contracting
and it shouldn't be,

"so try and suppress it."

So we're trying to train the brain
to turn on the muscles that should

be turned on, and actively turn off
the muscles that should be

turned off, and that way
we're letting

better control happen
in the hand.

Over the coming weeks,
they'll be doing this multiple times

to help build up Douglas's
surround inhibition response.

But today, the team plans to try
an even more cutting-edge treatment.

Transcranial direct current
stimulation.

So what we're doing is stimulating
the cerebellum, back here.

So that's the bit of the brain
that's involved

in motor learning
and motor function in general.

The theory is that motor memories
normally remain

securely locked in the brain.

But by recalling these memories,

by having Douglas play the guitar,
they will become vulnerable.

So this is a transcranial direct
current stimulator.

And these are the wires
that are attached to

the pads on Douglas's scalp,
and I'm just going

to plug those into the box,
to get the stimulation going.

Direct electrical current is now
flowing through Douglas's cerebellum

to try to disable the rogue neural
networks causing his dystonia.

The aim is to induce plasticity
in his brain

returning it to a similar state
it was in

when he first learnt to play.

We know from recent research
that memories

when they're stored in memory
are fairly solid,

they're fairly secure,
but when they're recalled

they go into quite a vulnerable
state, actually quite similar

to what happens when you're
originally laying down the memory.

So if we get Douglas to play in the
way that produces

the abnormal movement he
has with his thumb,

maybe if we're giving
some suppressive

brain stimulation at that time,
it might suppress the memory.

This is the first time this
technique has been used

to treat a musician with dystonia.

It's a dramatic show of just
how far our understanding

of the unconscious brain has come.

We're now at this very exciting
stage where we're

not just bystanders, just
looking at what the brain is doing,

we can actually interact with it,
we can stimulate bits,

we can turn bits up,
we can turn bits down.

And it's starting to
yield results,

and it's starting to give
us real insights

into how we might try to fix some
things in some quite precise ways.

But if you think that none of this
affects you, think again.

Because the unconscious mind
holds such potential

that scientists are now asking if
they can harness its immense power.

Every hour of every day,
your brain is flooded with images.

You can only concentrate on a few
at once, but all the while,

your unconscious will
be automatically filtering

this visual deluge.

The human brain is really
an amazing machine,

it's an amazing system.

I mean, one of the really
intriguing things about the brain

is that we're able to take this
visual chaos and clutter

and then find salient information
in that scene that matters to us,

that generates this, "Ah-ha, wait
a minute, I should look over there."

Using its own powerful internal
code, your unconscious decides

which information is worthy of
your conscious attention.

There are essentially these signals
that are labelling the world,

what we like to call neural
signatures

or neural markers that are saying,
"That might be worth exploring,

"that might be interesting."

Harnessing these signals
could change how we cope

with the data overload we all face
in the 21st century,

a prospect raising the interest
of the US military.

Afghanistan.

In war zones,
enemy bases can be hard to spot.

To find them, the military
rely on satellite images.

Hunting through these is a slow

and monotonous task that can't be
done automatically by computer.

An image analyst might have to look
at a very large aerial image,

for instance here, an image that's

tens to hundreds
of square kilometres.

The question is, "Where do I look
in this image to find buildings,

"to find objects of interest?"

But by tapping
into the power of the brain,

Professor Sajda thinks this process
can be dramatically shortened.

One thing we might want to do is,

instead of scanning this image from
the upper corner down,

have a more intelligent search
that's based on little regions

that grab our attention.

To do this, the satellite image
is randomly separated

into hundreds of sub-images.

A few show buildings, which is what
Professor Sajda hopes to find.

He will rapidly view
all the sub-images

while his brain response to each one
is recorded with this EEG cap.

This is an electroencephalography
cap, it allows us to detect signals

that would be related to what we
would call an "ah-ha" moment,

we see something of interest,
it catches our attention,

it generates,
"Ah-ha, that's important to me,"

and that information is transmitted
from this cap

to a computer which analyses
it to label imagery.

This is mind-reading,
21st-century style.

To begin with, Professor Sajda
looks at a sample image

containing a building.

The computer registers his resulting
neural "ah-ha" signal.

What we're interested in doing
is finding the patterns

that are related to this "ah-ha"
signal, and then use that

pattern of activity to rank all
the images that I'm going to see.

With brain and computer now linked,
the sub-images from

the large satellite picture start
flashing up on screen.

So what I'm doing now is looking
at a whole barrage of images,

five or ten a second,
and while I'm doing that my brain

is decoding that information
and using it to label the images.

So when you're looking at these
images, the best thing to do

is actually relax.

You get in to a zone
where your brain just does the work.

Professor Sajda is not immediately
aware of any images of buildings,

but his brain activity suggests
something very different.

Back in the main lab,
the results appear on screen.

What you see actually is a tiling
of the entire image,

where each of these little squares
is actually

one of the images as it was flashed.

They're colour-coded
based on the ranking

that was computed from
my brain activity.

So, essentially, how strong
was the "ah-ha"

when you saw that particular image?

So, regions that are marked
in red are very strong,

they grabbed my attention,
in dark blue are less engaging.

This little tile here is actually
the most highly ranked image.

This is a close-up of that
particular region.

What you can see here is this is
basically a compound.

There are roadways,
there's obviously a building,

some man-made structure.

So, the real gain here is that
instead of moving through

this large image very laboriously,
I can now jump

from image to image,
or location to location,

based on what grabbed my attention.

By tapping into his own brain,

Professor Sajda has increased his
image-spotting efficiency

by 300 percent.

It's a breakthrough, not
just for military image analysts,

but for everyone.

From interacting with
computer games, to advertising,

to revolutionising the analysis
of medical images,

the ability to harness the
power of the unconscious

heralds a bold new future.

The true nature of your unconscious
mind is now becoming clear.

Far from being the lowly,
primal thing of popular imagination,

your unconscious turns out to be

the sophisticated centre of
everything you ever do.

When it comes down to it,

your brain runs mostly
unconsciously, on autopilot.

And by tapping its immense power,

you might one day
change your life for ever.

The human brain is really
an awesome thing,

I mean, from the engineering
and technology point of view,

understanding the brain
will ultimately lead us

to areas
that we can't imagine.

I mean, if you think that
the internet

and networking and Facebook
have caused a revolution,

wait until you see what happens when
we really understand the human brain.

Subtitles by Red Bee Media Ltd