Episode 3 Incredible Medicine: Dr Weston's Casebook

We're discovering astonishing things about the human body all the time

through people who are different from most.

I'm Gabriel Weston.

As a surgeon, I've spent years studying the human body.

And the secrets of how it works are often revealed by the most

rare and surprising of cases.

So I've searched the world to find these extraordinary people

and bring you their stories.

This is my heart. I'm the only one that has this.

I'm Jordy Cernick, and I can't feel fear.

My name is Harnaam Kaur, and I'm a fabulous bearded lady.

With the help of the doctors that treat them and some of the

world's leading scientists,

I'll be uncovering exactly what makes their bodies unique.

'I'm going to show you the hidden

'processes that make them exceptional.'

Just look at that!

I'll discover how they're leading us to the cures of the future.

When we make a breakthrough like this, it is very exciting.

And I'll use the latest technology to uncover the secrets of

their bodies and reveal how all of these cases are giving us

a new understanding of the most amazing natural machine on

the planet - the human body.

'There are some extraordinary people who have talents and

'abilities that seem almost superhuman.

'In this programme, we'll discover why this woman can see

'millions of colours most of us can't...

'..and why this man never forgets a face,

'why this woman can smell disease before it happens

'and why this man has never felt pain in his life.

'I'll reveal how these remarkable people are helping us understand

'the most complex and mysterious part of our body, the brain.'

And I'm going to start with the strange case of

a man who awoke one morning with an astonishing new talent.

October 27th 2007 was a day

that would change Derek Amato's life forever.

I woke up and I could suddenly just play the piano.

Derek had never touched a piano before,

so how could he possibly become a virtuoso pianist overnight?

It began with a misadventure that might have killed him.

I was visiting some friends for a barbecue by the pool.

We were throwing a little football around,

and I just decided to go running along the pool and dive into the

shallow end to catch the football.

I struck the bottom of the pool with the upper left side of my head.

There's a moment when you hit your head that you know that

that noise is traumatic and you know something's definitely wrong.

Derek was rushed to hospital,

where he was treated for severe concussion.

He was sent home and slept for five days.

When he finally came round,

he felt an uncontrollable urge to do something he'd never done before.

My hands started basically understanding where they

were supposed to go and my brain seeing these black and white

squares telling my fingers what to do.

And then my brain started seeming like I started racing, to the

point where I was going...

..and then I was on overload.

What's so surprising is that Derek can't read a note of music.

He'd messed around with a guitar and drums as a child,

but he'd never actually learned to play an instrument.

Now beautiful melodies were tumbling out of him.

I had to play all the time, because it felt like if I didn't play,

it was like it was building up,

as almost if you were just pouring musical notes into my brain

and it was just filling up.

I just didn't know what to make of it.

I didn't know if I should tell someone,

because they're going to think I'm

nuts anyway, because I already had a head injury and now I'm telling

you I'm a piano player, so someone's going to have some questions for me.

Derek's story seems unbelievable, but he's not alone.

In 1988, Jon Sarkin, a chiropractor from New Jersey,

suffered a massive stroke and went into a coma.

When he awoke, he felt a sudden compulsion to draw and paint,

and he's a prolific artist to this day.

And in 2002, Jason Padgett, a furniture salesman from

Washington, was attacked outside a bar and suffered severe concussion.

When he recovered, he'd become a mathematical genius who saw

the world in complex geometric shapes.

It's a rare but recognised condition called acquired savant syndrome,

and what happens in it is that after damage to the brain,

an individual develops an ability that they never had before,

and scientists are trying to figure out what's happening in the

brains of these extraordinary people.

Professor Berit Brogaard is a neuroscientist who studies

acquired savant syndrome at the University of Miami.

She's been using MRI scans to look deep inside Derek's brain.

You see some white spots here, and there's

a small white spot here that we are particularly interested in.

These white spots are damage caused by Derek's concussion.

One of them lies in a part of the brain called the prefrontal

cortex that's involved in rational and logical thinking.

With this part damaged,

Derek now needs to use other parts of his brain.

When you give up on logical thinking and rational decision making

a little bit, you have the possibility of developing new

talents or become more creative,

more original, so original thinking,

thinking that actually results from not using the prefrontal

cortex but using other areas of the brain.

Berit believes that Derek's brain has quite literally rewired itself.

After brain damage, a powerful chemical called serotonin

encourages nerve cells in the brain, or neurons, to make new connections.

In Derek's case, these connections seem to have been established

in a part of the brain involved with creative thinking...

..which may explain his sudden musical talent.

And Berit's research suggests we might also have hidden talents that

could be unlocked by stimulating the brain in the right way.

In the future, we can use magnetic stimulation

or electric stimulation or perhaps a pill to unlock the abilities

that we see unlocked in people with acquired savant syndrome.

We can already improve people's drawing abilities and math

abilities, and it will only be a matter of time before we can

make people great musicians or great mathematicians.

What I think is the greatest gift is human potential,

and I think we have it in all of us.

It's not just me. Maybe I hit my head just right,

but I do believe that it's in all of us.

Derek's case shows how a small change in the brain can have

a huge impact on the person we are.

And there's one case in the history of medicine that was the

first to demonstrate just how much our brain controls.

Phineas Gage was an American railroad construction foreman

who, in 1848, defied the odds by surviving an accident in which

a large metal rod was driven all the way through his head,

nearly destroying his frontal lobe.

Now, when people were done being amazed that he'd survived,

what they noticed was that he was a different man.

Previously reliable, he became unpredictable and impulsive,

and he stayed that way for the last 12 years of his life.

His was the first case to show that the brain affects the personality.

Until then, it was believed that our

personality and abilities were God-given.

But this case demonstrated

that they're actually determined by our brain.

Nearly 200 years later,

we're still only scratching the surface in understanding what

all the different parts of our brain do and how they affect us.

And to unlock some of its secrets,

the next few cases I'm going to look at are remarkable people who

see the world around them in extraordinary ways.

James Rabbett is a man with an astonishing talent.

He can recognise just about every face he's ever seen,

even one he's only glimpsed for a few seconds...

..an ability that's beyond most of us.

Sometimes, when I'm going to meet someone on the weekend, I say,

"Let's meet at Waterloo station."

Because my brain is middle-aged, I can find it quite an effort looking

amongst all the people there to try and pick out my friend

or my brother or whoever it is I'm going to meet.

But James is different. He's what scientists call a super recogniser,

and he's about to have that ability tested to its limit.

Hello!

Dr Josh Davis is a psychologist from the University of Greenwich

who studies super recognisers.

He's trying to discover the full extent of their powers of

recognition and what can explain them.

Waterloo station, with these large crowds of people.

You've got to try and find my four actresses,

who have hidden themselves away in the crowd or be wandering around.

-It's really, really difficult.

-A big challenge, yeah?

-Yeah.

-It's really busy.

-So, here you go. Here are four targets.

What Dr Davis is asking him to do is have

a quick look at four photos of actresses that he's never

seen before and then look down on the concourse at Waterloo and

pick out these individuals

from in amongst thousands and thousands of other people,

none of whom James has ever seen before.

-I'm intrigued to see how you get on.

-It's going to be really challenging.

This is probably one of the hardest tests I've done, I think.

It's only recently that the very

existence of super recognisers was discovered.

Interestingly, James was working already as

a detective in the Metropolitan Police at Scotland Yard

and part of his job was to look through hours and hours of

footage of the 2011 riots, and he was much, much better at

picking individuals out from the footage than anyone else.

And he's actually become part of a very small team of detectives who

are known to be super recognisers and who are able to look at lots

and lots of photos of suspects and crimes and pick out the right

person in order that convictions can be secured.

So, what is it that gives these super recognisers their

extraordinary powers?

Well, we've only known about them for a short time,

so scientists are only just now beginning to uncover their secrets,

and it seems like the answer lies in a particular part of the brain.

Within our brain, this part, the temporal lobe,

is involved in perception and memory.

Deep inside it, scientists have identified a small area on

each side that becomes active when we recognise a face.

It's known as the fusiform gyrus, and it's thought to process visual

information from our eyes and allow us to recognise individual faces.

Scientists are now beginning to investigate whether the

fusiform gyrus might be especially powerful in super recognisers.

It may be that in super recognisers, this area may be working more

effectively, or it may be just passing information across

the brain more effectively.

We don't really know, but this is the sort of research that we

are interested in doing in the future.

At Waterloo station, James is about to try and identify four people

he's never seen before after just a brief glimpse of their photos.

-Black leather jacket, blue jeans.

-Brilliant!

-Pink laces!

Well done, because I thought she was the hardest.

-Is it the lady in the black jumper, cream top and blue jeans?

-Brilliant!

That was difficult.

White top, blue jeans, sandals.

Do you not think she looked so different in...?

Yeah, they are very, very different.

-This is her here with the handbag, blonde hair.

-Yeah.

-There she is.

Brilliant, well done.

-Congratulations.

-Thank you. Cheers!

It's impressive to see James do what's utterly beyond most of

us and correctly identify all four faces in a crowd.

When you were looking at the photographs at the start,

what were you trying to learn when you were looking at them?

I knew that they weren't going to be made up as they would have

been on the evenings when they were out having these photographs taken.

It's trying to get as much of the stable facial features as you can.

With yours, I had to take myself away from the fact that you

might have red hair or blonde hair or brown hair or whichever

colour hair you decided to have on the day,

so I just had to really focus on the nose, the mouth, jawline,

because I know that they were not going to change.

Robbie's wearing glasses. She's not wearing glasses in the photos.

-And again, you still see through that.

-Yeah.

You've got a distinctive jawline, your nose, the mouth as well.

You know, these features don't change.

Do you not think that's quite impressive?

-Could you have done it?

-No! I wouldn't have been able to do it.

It looks like we've done all right!

It's clear from the point of view of criminal justice why people

with this amazing extra quality are so useful.

But for scientists, working with super recognisers like James

is bringing a new understanding of how we all recognise other people

and of the complex and vital relationship between our eyes

and our brain.

It's that connection between our brain and our senses - vision,

hearing, touch, taste,

smell - that tells us everything we know about the world around us.

And our senses are some of the most intricate and sophisticated

systems in our anatomy.

And just look at the eye.

It really is one of the wonders of the human body.

Now, this complex biological camera delivers all sorts of

information to us in three dimensions and technicolour,

but I've come across a case recently

of someone who can see even more vividly than the rest of us.

I'm Concetta Antico, and I can see colours that nobody else can.

Like any artist, Concetta has an eye for colour,

but while most of see the world in a palette of a million colours,

Concetta can see up to one hundred million.

I really enjoy painting.

My eyes were always drawn to light and things of beauty,

things that were brightly coloured, and I felt this passion to

paint those images or those colours that I was seeing

from a very early age.

It affects me from the moment I wake up.

The light that's coming in is affecting my mood.

I walk down the street, and I'm not just walking down the street,

I'm looking at the colour of the little stones in the

concrete in the sidewalk.

Life with an almost superhuman

ability to see colour can be pretty intense.

'Shopping, for me, is difficult. It's too much.'

Can we go back to the old days, where there was just one

bottle of, you know, tomato sauce and one can of beans?

As an artist and art teacher, Concetta spent years

describing colours to her students that they simply couldn't see.

She had no idea why she was seeing colour differently until by chance

she heard of a rare condition called tetrachromacy that

affects the eyes.

It's the structure of our eyes that allows us to see colour.

If I dissect into it here, you can see just how complex it is.

At the front, we've got the iris and the pupil, the lens at the back,

and just here is the retina, where the image is formed.

On the retina are special cells called colour receptors, or cones.

These cones are triggered by different wavelengths of light,

and they fire off signals to our brain,

which combines them to produce all the colours we can see.

Most of us are trichromats, meaning that we have three types of cone.

But research suggests that some people are tetrachromats.

They have an extra fourth type of cone,

and this could allow them to see millions more colours.

To find out if she might be a tetrachromat,

Concetta began to contact scientists working in the field.

Dr Kimberly Jameson at the University of California, Irvine,

has been studying how we see colour for 20 years.

She agreed to test Concetta.

We're going to look at three colours from the same colour group,

and what I want you to do is pick the odd one out.

One of the three colours is very slightly different,

but only a tetrachromat would be able to see it.

-What number?

-21.

-21. OK. That was correct. That's the odd one out.

Three more. Look at them carefully.

Yep!

Good job, got all three correct.

Kimberly put Concetta through a series of different tests.

Try to make a smooth colour continuum and do it as

quickly as possible.

-That's kind of pulling them into the zone.

-Mm-hm.

-OK, I'm done.

-OK.

-Like that.

-Let's see how you did.

18, 19, 20, 21.

Good job!

So Concetta is able to detect minute differences between shades of

colour that look identical to most of us.

Kimberly has established that she IS a tetrachromat.

That fourth type of cone in her eye explains the overwhelming

range of colours she's been experiencing all her life.

And what's really fascinating

is that this extraordinary colour vision may only exist in women,

thanks to our DNA.

DNA is arranged in our cells into structures called chromosomes.

Men have one X chromosome but women have two.

And it's an abnormality, or mutation, on one of

those X chromosomes that causes the crucial change to the eye,

producing the fourth type of cone in the retina.

This is why it's thought only women can be tetrachromats.

But it's possible that this superhuman vision might not

be quite so unusual in the future.

Human visual systems are still evolving.

Here we are, perhaps on a cusp of human tetrachromacy

sort of mutating and emerging and being in a pipeline,

trying to understand where human vision and cognition is going

or could potentially go in future generations.

It is sort of like an amazing problem and an

amazing set of things to look at.

Perhaps one day many more women will have the ability to see an

astounding world of colour, like Concetta, but for now,

she remains exceptional.

It is a mutation. I call it a gift.

Will it become more expressed in our world,

and what does it all mean? I don't know!

It's going to be things that I'll never know. I'll be long gone.

But it's key to me and makes my life have meaning.

Concetta's eyes, with their remarkable colour vision,

give her brain a sensory overload,

but some people perceive the world around them in unusual ways

because a key part of the sensory system is missing.

All our senses have vital connections to the brain,

and I've come across a case recently that shows just how profound

the impact can be if one of these senses is severed.

There's one sensory experience that most of us do our best to avoid,

but Paul Waters has never felt it in his life.

'I don't feel pain. I feel everything else,

'I just don't feel pain.'

Come on, then!

Paul has never experienced an ache, throb or sting like the rest of us.

'I can feel pressure as opposed to pain.'

If I cut myself, for example, I would feel that as a...

..kind of...

I would say pins and needles would be the easiest way to describe it.

Paul's parents first realised something was wrong when

he was just nine months old.

There was an occasion where my dad had got in from work and

he trod on my arm, and my mum jumped immediately and said, you know,

"You're standing on Paul's arm."

They then sort of stood back and thought to themselves,

"Well, hang on a minute, Paul didn't flinch."

It was a kind of a sign that perhaps they should take me somewhere.

Doctors tested Paul and later his sisters and diagnosed them with

an extremely rare condition called

congenital insensitivity to pain, or CIP.

For most of us, if we cut our finger with a knife,

the cut activates nerve endings in the finger.

The nerve endings send an electrical signal through special cells

called pain neurons up to the brain,

and this is what we experience as pain.

But for some reason,

this system wasn't working in Paul and his sisters.

Growing up, me and my sisters would get up to a lot of mischief -

jumping off of high objects,

you know, at the risk of breaking a bone.

If a child breaks a bone, they're going to be in pain,

they're probably not going to do it again.

None of those negatives were present in me or my sisters,

so we used to do a lot of things

as children that other children wouldn't do.

An oven, to me, back then was a toy.

I'd put my hand in the hob just to hear it sizzle.

Now, it might sound like this condition is actually

protecting people like Paul from pain and harm...

..but our ability to sense pain is vital.

It alerts us to danger and helps us avoid it.

Not having it can be catastrophic.

One of Paul's sisters died as a result of an injury she didn't feel.

And Paul himself now lives with the consequences of

a lifetime of broken bones.

It's affected his height, and he needs frequent operations.

Ready? Scalpel...

Can we start?

So, why doesn't Paul experience pain, like the rest of us?

Well, his condition's very rare, so for years it's been a medical

mystery, but now one scientist is trying to get to the bottom of it.

Geoff Woods is a professor of medical genetics at the

University of Cambridge.

He had seen that CIP tended to occur in families, like with Paul and his

sisters, and so he knew it was most likely caused by a faulty gene.

It was such a rare condition that no-one had worked on it,

really, no-one saw any potential benefits to the condition,

and in some ways it was just forgotten about.

It was that sort of realisation that we could do this,

it could be a genetic disease.

Geoff knew that if he could find this gene,

then he might find the cause of CIP and perhaps even a cure.

His team began examining the genes of families with the condition,

searching for a mutation that they all had in common.

After ten years of painstaking work,

he eventually found what he was looking for,

a mutation in one particular gene that all the families shared.

He knew this had to be a key gene for controlling pain.

It was called SCN9A.

The day we sequenced SCN9A, my technician was looking

through the sequence results,

and all three families we used to map where the gene was,

we'd found mutations in them, and so we thought,

"Gosh, this could really exciting."

I think people had not expected that a single gene would be able

to control all pain sense in humans.

When our nerve endings sense something painful, they

trigger a surge of charged particles to flow into the pain neurons.

This stimulates the electrical signal to be fired

and sent up to the brain.

The SCN9A gene controls this flow of charged particles, but in Paul

the gene is faulty, and so the pain signal is never sent to his brain.

Geoff had finally found the reason why Paul and others with CIP

couldn't feel any pain.

With our patients who can't cause that electrical stimulus to be

fired, they've got their pain neurons sitting there but

they just can't respond.

Knowing the cause of CIP provides hope of

a cure for future generations of people like Paul.

But Geoff and his team realised that the discovery of

a gene for pain has wider implications for all of us.

If scientists can find a way to block the gene temporarily,

then they'll be able to produce more effective painkillers in the future,

essentially providing total pain relief for patients who need it.

It surely should be a goal that pain is a controllable problem.

The way we've made such huge strides in the understanding and the

treatment of cancer, that must be possible, also, for pain.

I would hope that,

as a result of the research being done into my condition,

that that can be used somehow to create something that would

act as a block to pain to someone who suffers from too much of it.

So use someone who doesn't feel pain as a way of helping someone who

feels too much pain.

Extraordinary people like Concetta and Paul are giving crucial

insights into how our senses work, but every now and again an

individual is discovered who has a sensory superpower with the

potential to change the course of medicine,

and I've come across a case recently that could provide

a breakthrough in diagnosing one of the most devastating diseases

of the modern age.

Joy Milne can smell things that other people can't.

As a nurse, I found I could smell a lot of things.

Blood has a definite smell.

I would say, "Oh, there's an awful smell in here," but I didn't

realise other people didn't have that sense of smell.

But even she was shocked to discover the true power of her nose.

It began with her husband, Les.

When Les was in his middle thirties,

I began to nag a little about his smell.

I just said to him he wasn't showering enough,

and then I had to say he wasn't brushing his teeth well enough,

and he was adamant he was doing both.

At the time, Joy didn't think much of it, but a few years later,

she noticed other changes in Les.

He....would miss things.

We were playing darts with the boys one night,

and he let the dart literally go through the front of his shoe.

Les was diagnosed with Parkinson's, a progressive neurological

disease that causes tremors and difficulties with movement

and can lead to dementia.

As they began to encounter other Parkinson's patients,

Joy noticed something extraordinary.

It wasn't until we went to our first Parkinson's group that I came home

and I said to Les, "They smell the same as you."

And he sort of... He said, "Are you sure?"

I said, "Yes. It has a smell.

"It definitely has a smell. These people smell like you."

'On the face of it, it seemed completely bizarre.

'Was it really possible that Parkinson's had an odour and

'that Joy could smell it?

'She was determined to find the answer.

'In 2012, she attended a talk given by Dr Tilo Kunath,

'a Parkinson's expert at the University of Edinburgh.

'At the end, she raised her hand to ask a question.'

I just said, "Why aren't we using the smell of Parkinson's?"

That was a pretty unusual question.

I've never had that question posed before, and I have to admit, yeah,

I was confused and I didn't know what you were getting at

-at the time.

-You were!

-Yeah.

Intrigued, Tilo contacted Joy after the talk

and was shocked to hear how she had noticed the change in Les's

scent before he was even diagnosed.

-Hi!

-Hello!

And I asked you questions like "Can you describe the smell in words?"

-Nasty.

-And woody?

-Yes, a heavy, musky smell.

-Yeah.

Tilo designed an experiment

to put Joy's remarkable claims to the test.

Could she really smell Parkinson's disease?

He recruited 12 volunteers, six with Parkinson's and six without,

and asked Joy to identify them based on the scent of their T-shirts.

So, she told us who all the Parkinson's patients were,

and then, of the six controls, she got five of them right.

And we thought, "Pretty good, 11 out of 12, that's quite a good score."

But nine months later, the patient that Joy had seemed to identify

incorrectly as having Parkinson's

was diagnosed with the disease. She'd been right all along.

My jaw just dropped, and I couldn't believe that she could predict

someone that was in the early stages of Parkinson's.

The tests show that Joy really can smell Parkinson's and, more

than that, she can detect it before a patient has any symptoms.

So, how is this possible, and what exactly is she smelling?

Every smell is a unique collection of odour molecules that

travel through the air.

These are picked up by chemical receptors at the back of our

nose which then send a pattern

of signals to a part of the brain called the olfactory bulb.

It's this pattern of signals that we interpret as a smell.

It could be possible that Joy's odour receptors are highly

sensitive compared to the rest of us, but more pressing for

scientists is to discover what exactly it is that she's smelling.

Professor Perdita Barran

is a a chemist at the University of Manchester.

Tilo asked her to analyse the T-shirts from the experiments.

But first, Perdita needed to know which part of them Joy had smelt.

Contrary to what we had assumed,

that the smell would be in sweat and therefore perhaps strongest

in the armpit areas of the T-shirts, it wasn't,

it was strongest in the middle of the back.

The middle of the back contains a large concentration of an

oily substance called sebum that protects the skin.

Perdita knew that there must be a molecule in sebum that Joy

could smell that was unique in people with Parkinson's disease.

She analysed the sebum from the T-shirts and

found 9,000 possible molecules.

What we are really wanting to find out is what is the difference

between 9,000 molecules in one person and 9,000 molecules in

a Parkinson's sufferer,

and potentially one or two or three molecules will be very different.

So it is a needle-in-a-haystack situation.

To identify the few molecules in 9,000 that are specific to

Parkinson's disease, Perdita needs a much larger number of samples.

So she's started a clinical trial involving sebum samples

from 100 people who have Parkinson's disease and 100 people who don't.

Perdita hopes that by identifying the molecule that Joy is smelling,

it could transform the way doctors diagnose and treat Parkinson's.

What we hope is that we will be able to develop a diagnostic test.

That's our primary aim.

We really hope that that will help to diagnose Parkinson's at an

earlier stage than currently available,

and at the moment there really isn't a test.

And all of that is thanks to Joy.

The possibility of an early diagnostic test for Parkinson's

disease could improve the lives of millions of people around the world,

all thanks to one woman and her very keen nose.

Joy's acute sense of smell gives her a special understanding of

other people, but, in fact, in all of us smell is inherently

associated with the formation of memory and emotions.

You might know this if a smell's ever reminded you of something.

And if you look at the anatomy, it's clear why.

Smell enters through the nose, and it comes up and is processed in

the olfactory bulb before sending signals to parts of the brain

called the amygdala and the hippocampus.

These two areas of the brain are crucial in the formation of

emotions and memory.

How memory works is one of the deepest secrets of the brain...

..one that scientists are unravelling thanks to

a few exceptional individuals.

This is Tracy Fitzgerald. Tracy lives in Boston, Massachusetts.

She's a student advisor, which would seem to be a normal job.

But Tracy has a completely extraordinary ability.

'I'm able to remember every day as if it were yesterday.'

She can remember precise events and the date they occurred going

back decades.

-INTERVIEWER:

-Can you remember what might have happened

-on February 11th 1990?

-Yes.

February 11th 1990 was the day that Nelson Mandela was released

from prison.

16th of October 1978.

The 16th of October 1978, Pope John Paul was named Pope.

November 9th 1989 was the day that the Berlin Wall officially

came down.

Do you happen to know the date that Diana and Charles got married?

July 29th 1981. It was a Wednesday.

Tracy doesn't learn these details by rote.

Her extraordinary recall goes way beyond the day's headlines.

I'll go back to 2010 and think of March 4th.

It's almost instantaneous. It's kind of like a DVD

is being put in and then set to play, and I'm recalling.

A large portion of information will immediately hit,

and then the rest kind of comes in like snow,

almost like a game of Tetris, starting to fall into place.

That year, on March 4th,

members from my office decided to go have an impromptu after-work

gathering at the local pub,

so now I've just remembered that before I was able to go to that,

I also had to go to a bank and make a credit-card payment, because

my credit-card payment was due on March 4th, and I think

I made the minimum, like, 85 payment that day

and was able to take out some money, 20, to be able to go to the bar

and join my friends that afternoon, so that information's coming in.

Tracy can remember this kind of precise detail from almost

every day of her life for the past 40 years.

It's a condition called highly superior autobiographical

memory, or HSAM.

For someone with a normal memory,

and certainly someone of my age who, I don't know,

I feel like I'm losing memory and details all over the place,

you watch her doing this and it's just completely astonishing.

Sometimes I begin my day or I end my day thinking about that date

and then going back in time to see if I can identify what I was

doing for the past year or so.

Those are some of the typical exercises that I do just for fun.

'Tracy's memory skills are incredibly rare,

'so what is it that enables her to have this exceptional recall?'

One scientist is trying to unlock the secrets of what's happening

inside the brains of people with this extraordinary condition.

'My name is James McGaugh, and I'm a professor of neurobiology and

'behaviour at the University of California, Irvine.'

Over the past 15 years, James has studied over 60 people with HSAM.

It's not that they have a very strong memory to begin with.

As a matter of fact, we are as good as they are for 24 hours.

So if you think about it, their autobiographical memory is just like

ours for a period of time, then we forget and they tend not to forget,

and that's the difference.

It's not just a strong memory, it's a very severe inability to forget.

To discover how this is possible,

James's colleague Dr Mike Yassa has been using an MRI scanner to

look inside the brains of people with HSAM.

He's comparing the structure of their brains with those of people

with normal memories, and he's found three intriguing differences.

This area here, called the striatum,

which is about the middle of the brain,

this is a region that's been implicated in habit formation

and habit learning, and that region seems to be slightly enlarged

in individuals with this ability.

There's a second area that's enlarged in people with HSAM,

the parahippocampal gyrus, involved in learning and memory, and there's

a pathway known to be involved in transferring information

around the brain that's also more pronounced.

So the scans have revealed what's different about the brains of

people with HSAM.

But to find out why these differences exist,

James has begun an exciting new phase of research.

'My name is Tyler. I am 13 years old,

'and I have highly superior autobiographical memory.'

Tyler is one of the youngest members

of the group being studied by James McGaugh.

He displays the same abilities as Tracy.

What was Thanksgiving in 2014? That was two years ago.

-The 27th.

-Correct.

Scientists think that Tyler might finally bring

a breakthrough in understanding HSAM,

not only because he's 14 and they can watch the condition develop

throughout his life.

Tyler brings a double opportunity...

..because this is Chad...

..Tyler's genetically identical twin brother.

And he doesn't have HSAM.

It's kinda cool, cos, like, if I don't remember a date for a certain

thing, say my parents ask me, he always remembers it and can tell me.

So, yeah, that's kinda cool.

In 2013, what was the day of the week before Halloween?

-Thursday.

-Correct.

-A Saturday? No, wait, Friday. Yeah.

-Close. Not quite.

Oh...

Two people of the same age, same background, same family,

and we'll find out, hopefully,

why one of them is able to have it and one does not.

Here's a couple of twins who share a genetic code who are going to

provide Dr McGaugh with a remarkable opportunity to try

and identify what it is that makes people with HSAM different

from people without HSAM.

If we can learn something about how their brains work and how

their brain working differs

from those of people who do not, that will

be a new chapter in understanding the neurobiology of memory.

Every waking moment,

our brains are taking in a massive amount of information from

our senses and adding it to the memories that are already

stored there,

and it's this wealth of information that enables us to survive

and navigate through our lives.

These extraordinary cases that we've been looking at are enabling

scientists to work out just how the brain can do all this.

But sometimes science can learn the most when the power of the

brain is taken away, as our final case shows.

'I remember just seeing complete black.

'I guess my eyes weren't connected to my brain yet.

'I felt like I was a prisoner in my own body.

'This event changed my life forever.'

Three-and-a-half years ago,

Juan Torres was trapped in a seemingly vegetative state,

awake but unable to communicate with the outside world.

No-one expected him to recover.

The very fact he's talking to us now is truly astonishing.

CHATTER ECHOES

I remember going to a party.

And then I remember coming home.

Juan has no memory of the events that followed.

Mysteriously, something happened in the night that led to him

having a respiratory arrest. He stopped breathing.

And his mother, Margarita, obviously called the ambulance,

where he was rushed to hospital and doctors attempted to save him.

'They were struggling to keep him alive.'

But there was a moment where they told us,

"He's leaving, basically he's leaving. You can say goodbye."

But Juan survived.

When the doctors managed to get him through that period of time

where they thought he might not live,

the best that they were able to come to Margarita and tell

her was that he was still alive but that he was in

a vegetative state and would not recover.

As his mother was being told that story,

Juan was in the room hearing everything that was being said,

recognising the world around him and knowing that

he was still conscious, but in his case, he didn't even have the

ability to blink his eyes to let someone know that that was so.

It felt horrible.

I couldn't even cry...

..because I guess my brain hadn't got reconnected to my tear ducts.

For over two desperate months, Juan remained in what's known as

a locked-in state, conscious but unable to communicate.

Margarita is clearly an amazing woman,

and even in the face of doctors saying to her,

"We're really sorry, we've done the best we can by your son,

"he's alive and breathing but he's not there any more,"

she just chose not to believe that.

Sometimes, it was hard to stay positive because there would

be many days and hours where you don't see a glimpse of anything.

I love you, baby.

Do you see the nice place?

They have a beautiful garden outside, and park.

And then, one day, without warning,

for reasons that aren't understood, something truly remarkable happened.

We took him with my husband, and it was a sunny day, beautiful day.

That was the first day that he came out of the room.

I remember being outside.

And my mum said something like, "Come on,

"you're always my little Snow White." And then I chuckled.

And that's when they knew.

Oh, my God. It's very...!

'We were laughing. And so he started to laugh.'

Sleeping Beauty? Yeah.

'I remember feeling really happy.'

That was to me a very specific sign that he was going to come back.

Juan had finally been able to let the people around him know

that he was still conscious.

They were ecstatic.

I felt joy.

I remember I was just...kept telling myself that...

I'm going to walk again. That's what drove me.

The fact that I had it all,

and I was going to return to having it all.

THEY SPEAK IN SPANISH AND LAUGH

Why he was suddenly able to start communicating like this is

something that science can't completely explain.

And how and why this happens in some patients and what triggers it

are some of medicine's greatest unknowns.

The difficulty for us doctors is in trying to establish exactly

which patients are in a truly vegetative state,

and which are aware of what's going on but unable to communicate.

In short, which patients will get better.

One man is trying to find a way to answer this question.

Adrian Owen is a neuroscientist from the University of Western Ontario.

He tested Juan when he seemed to be in a vegetative state.

Down, roll over!

And Juan's recovery offered a rare opportunity to discover how

much he'd actually been aware of at that time.

Once we heard he'd recovered, we very quickly brought him back

here to London, Ontario, and we put together a memory test.

We asked him things like which of these two people do you recognise?

Of course, he could identify my research assistant who'd

tested him on that day.

What we have to remember is that, at the time, Juan appeared to be

in a vegetative state. He was entirely non-responsive.

His eyes were open but there was

no evidence he was aware at all, yet he could remember people.

He could remember places.

And he could remember things we'd done to him.

Dr Owen was only able to find out that Juan had been aware of

what was going on after he'd already recovered.

He needed a way to find out which patients were truly vegetative

and which patients were locked in and had a chance to recover.

He decided to look inside their brains.

So, what Dr Owen's been doing is putting all of his patients,

who are in a vegetative state, into what's called

a functional MRI scanner,

which is a machine that looks at the brain and,

in response to certain questions, shows different levels of

blood flow to try and identify that there's some function there.

When you hear the instruction to begin,

please imagine playing a game of tennis.

We know that when people imagine playing tennis,

a part of the brain, known as the premotor cortex, lights up.

It's the part of the brain involved in moving your arms around,

as if you were playing a game of tennis.

If I say imagine playing tennis to you and your premotor cortex

lights up, I know that you've understood the instruction

and you've followed the command.

By scanning patients' brains in this way,

Dr Owen has found that nearly 20% of people who appear to be in

a vegetative state are in fact conscious and aware.

And now, thanks to this research,

scientists are closer to understanding how more

patients like Juan could be brought out of their locked-in state.

20 years ago, when I started working in this area,

nobody was interested in the vegetative state

because it was thought to be a hopeless condition.

Well, now we know that in some cases there is hope.

Now we know that in one in five cases there is awareness when

everybody else thinks there isn't.

One in five is a staggeringly high number.

But it's never going to be possible to take every patient

in such a critical condition

to an fMRI scanner to test their brain responses.

And this could mean that not every locked-in patient is identified.

The difficulty with fMRI scanning all of these patients

is MRI scanners are very heavy and not movable.

So, Dr Owen's come up with a brilliant solution to this problem.

This is the EEJeep. It allows him to take his testing on the road.

He uses a different technology to measure brain activity

so that critically ill patients don't have to be transported to him.

He can go to them.

There are 129 electrodes,

and each one of these will pick up a little bit of the electrical

activity that your brain naturally and continuously produces.

The way fMRI works is by measuring or by monitoring

how blood moves around the brain.

EEG works in a completely different way,

which is that it detects the electrical signals coming

from the activity of neurons in the brain.

It's actually a different way of looking at the same thing,

which is, essentially, which areas of the brain are active right now.

Dr Owen's research is bringing us closer to understanding why

patients like Juan recover and how we can identify others like him

so that we can bring more people back from being locked in.

Three years on, Juan is studying life sciences at university.

And learning to walk again.

You've got to put one foot in front of the other. That's how you learn.

I'm going to be walking in a year.

Exactly a year from now.

Or less.

I feel that we all appreciate life in a totally different...

manner than we used to.

It is amazing.

Juan was brought back from the edge of oblivion,

a terrifying experience.

But from this and all the other cases we've explored comes a better

understanding of the extraordinary power of the human brain.

It reminds us of the super abilities that our brains give us

and how they can sometimes recover, even in the most extreme cases.

Next time, I'll discover why this man can run for three days straight.

Some of the races I've run have been 200 miles.

Why this woman has to battle the whole world.

I'm allergic to everything.

And why this woman once had two hearts.

I always think of all the doctors, all the surgeons.

I wouldn't really be here without them.