Heart vs Mind: What Makes Us Human?

My name is David Malone.

I am a science documentary filmmaker.

And I have come to Papworth Hospital in Cambridgeshire.

It's the first time you've been in theatre?

Yes. I don't know what I'm doing, but I'm good at following orders.

I'm here at the invitation of consultant surgeon Mr Francis Wells,

who is going to allow me to watch him perform open-heart surgery.

He's got a leaky aortic valve.

I've always wanted to see the beating human heart.

That thing within us that keeps us alive.

You'll see when you get in here how colourful the human body is. It's amazing.

You sound like it's never lost its thrill for you.

No, not at all.

The heart is unlike any other organ in the human body.

It has its own rich language and poetry.

Throughout history, it has been a potent symbol in our religion,

literature and philosophy.

It has been seen as the site of our emotions.

The very centre of our being.

But modern medicine has come to see the heart as just a pump.

A brilliant pump, but nothing more.

And we view ourselves as ruled by our heads

and not our hearts.

-So, that's the valve actually going into place?

-Going in, yes.

And yet there's something about the heart that makes me wonder

whether there is more to it than this.

You open up this body that's lying still

and inside there's this other creature, struggling away.

So I want to explore the story of the heart.

How it came to lose out in the age-old battle of hearts and minds

and ask whether with the help of modern science,

the heart may reclaim its traditional place

at the centre of our lives.

There's the heart working. All back in one piece.

Open-heart surgery is one of the great triumphs of modern medicine.

I have to tell you, it's the movement which I find extraordinary.

The liver sits there looking ugly. The spleen sits there looking ugly.

The bowel sits there smelling awfully.

-The brain sits there...

-Doing nothing at all.

To perform operations like this,

surgeons can't help but view the heart as a machine.

Something that can be fixed when it goes wrong.

But for Mr Francis Wells, one of Britain's leading heart specialists,

this is a machine that can still inspire wonder.

-What we see is a bit of muscle contracting here.

-Yes.

What's going on inside the cells at a metabolic level

is immensely complicated.

You work with these hearts everyday.

You see them, the mechanical side of human nature.

Yes. There is a mechanistic side to it

which is easily appreciable

and learnable and correctable.

But, um...you rapidly appreciate that it isn't just mechanical.

Biological structures and tissues

are beyond mechanical.

It has a life. It has a momentum.

For Mr Wells, the heart's extraordinary biology

gives it a beauty all of its own.

He sees no need to romanticise the role of the heart

beyond its vital function as a pump.

-Thank you. It was a privilege.

-No, not at all.

I suppose what I'm looking at is, how much of that wonderful poetry,

the romantic poetry of the heart,

-is just poetry...

-All of it.

And how much of it is a poetic

report about something that...

You've answered the question yourself

because you made the point at the beginning

-that you'd never seen a human heart before.

-No.

And I would bet you that 99.99% of the poets of the past

have never seen a human heart before.

We all like this emotional interplay.

But the heart is a bunch of muscles

with some nerves that stimulate it.

And it has some chemical receptors

which allow it to respond

to chemical and neurological stimuli.

Whilst we all want to think of it

as being this incredibly fanciful structure, and we all do,

in reality, it's a pump.

That's what it does.

I know I can take the heart out and you can still fall in love.

I can take the heart and the liver out and you'll still fall in love.

I take the heart, liver, lungs and bowel out, you'll still fall in love.

Well, that's useful to know in an emergency.

It's true. We've done it.

But if I asked myself what part of me feels love for my family,

I would say I feel it in my heart.

I love my three sons with all my heart.

And when I first met my wife Sarah, my heart skipped a beat.

This is the familiar language of the heart.

One that talks about being broken-hearted.

Or your heart swelling with joy.

The whole reason we're making the film

is to explore that poetic language of the heart.

His heart swelled, his heart jumped,

his heart burst, his heart broke.

I suppose what we're asking is,

how much is that language just poetry

and how much of that poetic language

is an accurate description

of something which is true, just said poetically?

And I don't know yet.

Why this matters is because I believe our view of the heart,

in some fundamental sense,

is a reflection of how we see ourselves.

The problem I have with the modern view

we have of ourselves and our world

is not so much that it's soulless as heartless.

We're encouraged to view ourselves as if we live just in our heads.

As if our brains rode around in our bodies

the way that we drive our cars.

And for me, that means we...

we relegate everything that we feel

as if somehow our emotions were less important

than our thoughts.

Yet for much of human history,

we saw that what made us wonderful creatures

was not our brain, but our heart.

But was this very different way

in which we used to see ourselves so misguided?

Richard Parkinson is a curator at the British Museum

and is showing me a papyrus over 4,000 years old from ancient Egypt.

This is the famous papyrus of Ani,

which is part of one of the funeral papyri.

For the ancient Egyptians,

the heart was the most important organ in the human body.

It's very much the symbol of the mind, the emotions, the character.

Everything is represented by that particular organ.

And did the ancient Egyptians

-believe that was the centre of their being?

-It seems to be that way.

All the language refers to the heart in descriptions of character.

If you're greedy, you're grasping of heart.

If you're patient, you're enduring of heart.

The heart is the one thing that really anchors ideas of personality.

The papyrus depicts a scene called the weighing of the heart.

The ancient Egyptians believed a person would only pass into the afterlife

if their heart balanced against the feather of truth.

If not, the heart would be eaten by the devourer

and they would become nothing.

Why balanced against truth? I mean, it's lovely.

Truth is the...Egyptian way of life.

It's something like justice, truth, order

in society and in the personal life, in the cosmic life, as well.

-And your heart has to be exactly in tune with truth.

-With that truth.

And so, above the heart in the papyrus

is the famous heart spell, which just begins here.

You can see the sign of the heart there. My heart.

-Can you read that?

-It's standard Middle Egyptian.

He addresses his heart. "My heart of my mother.

"Do not stand up against me as a witness

"and oppose me in front of the company of gods."

-He's talking to his heart?

-Yes.

-Keep the heart quiet. Don't let it give the game away.

-Because the heart tells the truth?

The heart might tell the truth if he's encouraged too much by the judges.

The heart, physiologically, it does tells the truth.

In the sense that when you try to lie,

your brain says, "Let's keep calm. Let's not give anything away."

But your heart starts thumping, you start sweating.

So the heart, it really is the organ

which can't help but give you away if you're not careful,

-which makes that practical admonition so lovely.

-Absolutely.

It must have been a very well-fed monster.

Some of them look quite eager.

The ancient Egyptians did not understand

that the heart pumps blood around the body,

but they did recognise a quality about the heart just as profound.

That when we tell lies, it is the beating of our hearts that can betray us.

I have to say, I like the ancient Egyptians. I like the fact that...

..they see the heart as being connected with truth.

Not something airy-fairy like love, but truth.

That it simply tells you the truth about how you are,

what you are feeling, what you think.

And they were right.

As the earliest scientists began to explore the heart,

what was seen seemed to reinforce the notion

that this organ of truth and emotion

was also at the centre and beginning of life.

It was the Greek philosopher Aristotle who first glimpsed

this remarkable sight of the embryonic beating heart.

For Professor Thomas Brand, developmental biologist at Imperial College London,

what amazed Aristotle has lost none of its magic.

-How old is this one?

-Three days.

-And you can see it fills up and empties.

So you get to see the whole pulsing.

Yes. You see the entire cardiac cycle happening.

Here we have the eye, here the ear.

And here the future jaw.

Aristotle could see that the heart

is one of the very first organs to form in the embryo.

And he recognised that the embryo could only develop

with a healthy beating heart.

It was vital to life.

Certainly, Aristotle was the first one to realise

that there is something like, er...

something forming in the yolk.

It was quite an accomplishment

to see the heart all of a sudden there.

What did he conclude when he saw this? Did he...?

Well, he saw that the heart is actually forming first

and then from the heart, all the other organs

are derivatives of, or actually used by the heart.

-Really?

-And this is a concept

that has some truth to it.

Right from the start of life,

the heart is driving the development.

Yeah. The heart is very important. It's very essential.

If an embryo like a chick embryo has no heart,

it would stop developing right way.

This is a chick, but would we see something similar

if you were looking at, say, I don't know,

a dog or an ape or a human?

They would all look the same way.

So this is a very basic blueprint that life has found.

Correct. If you would see...at his stage,

if you would look at any other embryo,

they would look almost the same way.

Aristotle had established the heart

not just as the seat of our emotions

and the teller of truth,

but also the force in the body that keeps us alive.

But this was also the time of the birth of philosophy

and a view began to emerge that thoughts were different to emotions.

That each belonged to different parts of our bodies.

Our heart, and our brain.

The idea was promoted in the writing of the Roman physician Galen.

For Galen, the head is associated with reason.

The abdomen is associated with the heart and with passion.

And the lower regions are associated with procreation.

So that is his way of understanding how the body functions.

That's the first time we really have a separation

between the emotional heart and the rational brain.

Galen's views dominated western thought for over 1,000 years.

The heart reigned unchallenged as the seat of our emotional lives.

An idea expressed in art,

literature and religion.

But in the 17th century,

our entire understanding of the heart changed.

The English physician William Harvey made a discovery

that would give a new role to the heart.

Harvey was interested in how blood moves through the body.

According to Galen, blood flowed like the tide,

ebbing back and forth.

There was no circulation.

The arteries and veins were entirely separate.

Harvey showed this was wrong.

Today, we're going to look at the small blood vessels in your fingers.

Dr Art Tucker is a clinical scientist

at St Bartholomew's Hospital in London.

He's able to show me what Harvey knew must be true,

but was never able to see with his own eyes.

That if the blood circulated,

then the blood that flowed out must somewhere turn back.

The arteries must become veins.

And there they are.

-Those little loops?

-Those little loops.

These beautiful ghostly figures

are the capillaries in my fingernail.

It's in the capillaries that arteries turn into veins

and blood begins its return trip back to the heart.

-I can see something going around.

-That's blood.

-Am I really seeing that?

-Yes.

Even after...I've been doing this nearly 20 years,

seeing these always excites me.

It's fantastic seeing...

-suddenly seeing them...they seem to fill up.

-Yep.

-So you see that...?

-Whoa! I saw it zip around there.

And this, in one aspect, truly demonstrates

what Harvey was trying to say.

In that the blood flows in a circulatory path

rather than flowing, as Galen said, like the tide, in and back.

And if you look carefully, the blood flows up one side...

..around the loop and then returns.

That blood is on the return journey back to the heart and lungs,

where the carbon dioxide will be removed

and the oxygen will be replenished.

Harvey goes down in history as the man who first realised

that the same organ understood to be the centre of our emotions

also pumps blood around the body.

For Harvey, his discovery did not diminish the heart,

it added to its grandeur.

But the time in which he lived, the dawn of the mechanical age,

interpreted his discovery very differently.

In the mind of one man in particular,

the French philosopher Rene Descartes, a radical thought took hold.

Descartes was in love with the mechanical and the rational.

And it seemed only natural to him to re-imagine the human body and mind

in terms of the cogs and wheels of the early industrial revolution.

I think for Descartes, the notion of metaphor is very important.

Because he wants this entirely mechanical account of the world about us

and he wants to use mechanical analogies within that.

He wants to say that things are like pumps,

they're like engines, they're like clocks.

Because these are the sorts of things that fit well with his notion of the world.

Descartes' ideas recast the human body as an elaborate machine

with the rational mind now in command.

The stomach and intestines as some sort of refinery

where fuel is processed.

And the heart...no longer the seat of emotion

nor truth teller.

Now nothing more than a mechanical pump.

And it was Harvey's discovery seen in the capillaries

that made this view of the heart seem indisputable.

Zealous believers of Descartes' ideas

could even dismiss the cries of pain from tortured animals

as nothing more than the creaking of animal clockwork.

They were becoming just like their machines, cold and mechanistic.

Devoid of feeling.

If you want to find one moment where the new view replaced the old,

it's when Harvey's work seemed to give licence

to applying this mechanical metaphor,

not just to the outside world, but to us, as well.

Which was ironic because Harvey himself didn't like this new view.

And that in itself is quite telling.

In Harvey, it's almost as if you can see how the heart

was unable to defend itself

against the triumph of the rational mind.

That triumph might have been lessened

had Harvey and the others of his time

known more about how the heart pumps blood.

In particular, had they known about a discovery

made over a century earlier

that painted a picture of the heart very different

from the crude mechanical pumps of the industrial age.

In the Royal library at Windsor Castle,

curator Martin Clayton is showing me

beautiful anatomical drawings by Leonardo da Vinci.

Drawings that were neglected for almost 400 years after his death.

They document da Vinci's remarkable understanding of the heart.

These are drawings from almost the end of Leonardo's anatomical career.

Done about 1512, 1513.

So Leonardo was 60 years old or thereabouts

when he made these dissections.

It was what Da Vinci discovered

about how blood flows through the valves of the heart

that was most important.

In a remarkable experiment,

Da Vinci constructed a glass model of the heart's aorta,

the artery which takes blood away from the heart to the body.

He deduced that as the blood flows through the valve into the aorta,

it must make a beautiful swirling pattern called a vortex.

And then he describes how he would pump water

with a suspension of grass seeds through his glass model

so he could observe what were vortices

in this chamber now known as the sinus of Valsalva,

just above the aortic valve.

And he surmised that the purpose of these vortices

was to open out the valves.

This graceful pattern is called a ring vortex.

Da Vinci understood that blood creates this shape

as it flows through the valve into the heart's aorta.

His key insight was that this swirling of the blood

does not work against the heart, but with it.

Helping close shut the flaps of the valve behind.

The workings of the heart had a natural beauty.

Totally unlike the crude mechanical pumps

of the industrial revolution.

Doesn't it strike you as one of those moments in history where if we'd gone that way,

if someone had said, "Show me that again, Leonardo,"

we would have had such a different view of what we meant by a pump.

I think what people had in mind was the kind of drum with a stick that goes in and out, which...

So when people said, the heart's the pump, that's what they had in mind.

-And it's nothing like that!

-Something so sympathetic to the structure of the heart.

The awareness that it's not just an accidental form or a crude form.

Da Vinci had realised how the movement of the heart

and the flow of blood work in natural harmony with one another.

First scan starting, David.

OK.

David, can you take a breath in, please?

Using modern magnetic resonance imaging,

it's possible to see in beautiful detail

the way in which the blood flows through the heart.

David, this is longer, it's about 20 seconds.

ROBOTIC VOICE: Please breathe in. Breathe out.

And hold your breath.

Thank you, David. We're finished. Very good images.

It's not always the case. Thanks.

Dr Philip Kilner is a consultant in cardiac imaging

at the Royal Brompton Hospital in London.

-Is that me?

-This is you, absolutely.

-And, er...

-Let's have a look.

Oh, my God!

We're looking from below, in this case, towards the head.

That was my heart as it was beating a few minutes ago?

-Absolutely. Yes.

-Am I imagining...? I mean, I...

I'm thinking that I can see all sorts of complications in the flow.

-Is that real?

-Yes, that's real.

That gives you a fairly genuine impression of flow.

It's averaged over a multiple heartbeat, so it's not quite real-time.

And it's to do with the tuning of the magnet

that you actually see dark blood joining it.

But nevertheless, that blood is showing us...

You can actually see how complicated the swirls are in there.

-Yes.

-It curls around, swirls here and then it's...

What's interesting is that if you listen to somebody's chest,

you can hear the heart sounds, often described as

lub dup, lub dup.

The timing of that is like this.

Lub, dup.

Lub, dup.

-Right.

-Lub, dup.

The deeper sound, the lub, is the closure of the inflow valve.

And the higher-pitched sound is the closure of the aortic valve.

It opens and closes roughly every second, faster if you're exercising.

-For my whole life?

-Your whole life, day and night, non-stop.

-Yes.

-That's about a million times every ten days.

What a piece of engineering!

It's stunning.

This beautiful three-dimensional scan of a patient's heart

was made by a colleague of Philip's in the United States.

The blue shows the blood depleted of oxygen

coming back from the body

through the heart on its way to the lungs.

And the red and yellow shows the oxygenated blood

coming back from the lungs,

through the heart and back out to the body.

And if I walk you around this image, if I tip it like this,

we're looking as if from the left shoulder.

And now you can begin to see vortices in the left atrium

-are swirling around.

-Oh, yes, you can!

And in the left ventricle, swirling mainly around the anterior mitral leaflet.

You can see it's coming in, shooting down here, curling around

-and then is directed back out that way.

-Yes. Absolutely.

So the heart doesn't really have to shove the liquid

in a way that the liquid doesn't want to go.

The liquid is heading there because of the shape of the heart.

To some extent, I think that's true.

Especially unexercised, I believe that's true.

It's halfway between engineering and art.

There's a beauty to it.

To imagine it all but in series,

and simultaneously flowing day and night, non-stop,

throughout your life.

-That's the most beautiful thing I can imagine.

-Yeah.

It is almost as if the flow of blood

has carved out the shape of the heart through evolutionary time.

The chambers of the heart are shaped in such a way

that the blood swirls around in the direction the heart requires.

Even the vast loop made by the blood as it flows around the heart

means that as the main pumping chamber recoils,

this helps the upper chamber refill with the next batch of blood.

And part of this astonishing beauty of the heart

had been glimpsed by Leonardo da Vinci.

When you look at these two pictures,

what you see here is the world of Leonardo or Shakespeare.

This is the beginning of modern science.

Thrilled at exploring the nature of being human.

A couple of centuries later, it's completely changed.

Here you have our culture,

thrilled with exploring the world

of gears and cogs and pulleys and ratchets

and re-imagining us as if that's what we were.

Mechanising the world has brought great benefits to human kind.

We have built vast cities, industry and advanced technology.

But mechanising the heart has, I believe,

done untold damage to how we see ourselves.

This tendency to see things in mechanical terms

is something that psychiatrist Doctor Iain McGilchrist

has spent 20 years thinking and writing about.

That machine metaphor, it does do a lot.

I mean, it has done a lot.

We've built a mechanical world full of flashing lights and things that whizz around.

It's enormously successful at doing certain things.

And that's very seductive.

But what it's not good at is describing...what we are.

I mean, it can describe really well

the mechanical pumping aspects of the heart,

and that's fine, but it excludes a lot.

We think we're understanding, but what we're doing is describing mechanisms

so that we can usefully intervene in them if we need to do so.

-Yes. Medicine.

-In that sense, they're like maps.

When you're driving, you want a map.

You want to know where you're going and how you're going to do it.

But you wouldn't be so foolish as to mistake that map

for a full description of the world.

It's only telling you the things it is there to tell you about.

The problem with the mechanical model is it's just telling you something very important,

very useful, very helpful.

So it's been a great advance for us that we can see these things,

but the mistake is to think it tells us what we are.

I think seeing the heart as just a mechanical pump

has encouraged us to view our bodies as machines

ruled over by our heads.

And this has led us to accept that emotions and feelings,

these things that were historically connected to the heart,

are somehow less important.

But recently, I began to question this.

If I'm being honest about it...

I've spent a lifetime seeing myself as a rational person,

essentially summed up by the rational mind,

living in a rational world, making rational decisions,

and I have emotions and that's fine, like everybody else.

Then something...

An emotional storm breaks out in your life.

You realise there's a whole side to your life,

a powerful emotional life,

which I can't think of any longer as just, "I have emotions."

I think emotions are, they're like the tide you bob about on

and if a storm breaks out, God help you.

But there's no point in denying that side of you.

I think we're not so much

rational creatures who happen to have emotions

but emotional creatures who have thoughts.

And our hearts remind us of this.

I've come to believe that seeing the heart as just a pump

does not just distort how we view ourselves,

but may also be fundamentally wrong.

Modern science is now beginning to understand the heart

in a way that is much more nuanced and complex.

Some scientists are beginning to return emotion back to the heart,

exploring how what we think and feel can profoundly affect the heart,

even, in extreme cases, causing it to fail altogether.

Professor Peter Taggart

is a cardiologist at the Heart Hospital in London.

If you take the English language, for example,

there are expressions like died of fright, worried to death,

but everybody believes that emotion affects the heart

but scientifically, there's very little evidence

and very little credibility for this,

so we're trying to actually bridge that gap

and provide hard scientific facts

about the way that it does affect the heart.

So specifically, what is it

that you are actually looking for in your experiments?

Well, the ultimate goal, of course, is to look at the way

that emotion may contribute to sudden death, sudden heart deaths.

There are a lot of anecdotal examples, as you know,

of people dying in the course of an argument

or after a bereavement or some bad stress.

There's several studies showing that heart deaths go up dramatically

-after natural disasters such as earthquakes...

-Really?

Wars, and things like that.

-Not dying from the actual event, but afterwards?

-Just afterwards.

But we don't know how, in fact, this happens.

And our work, really, is to try and actually understand the mechanisms.

How does emotion affect the heart itself to create these problems?

OK, breathe normally.

OK, I think we could probably take the tube out.

-Are you happy, Peter?

-Yes indeed.

-OK.

Can we take the tube away, please?

Professor Taggart has invited me to St Thomas's Hospital

to see an experiment exploring the surprisingly complex way

in which emotion can effect the heart.

A little bit more pushing.

This patient has a problem with his heart

and has come to hospital for treatment.

A series of catheters are being fed through his blood vessels

into the heart's inner chambers.

Just going to put a little more local anaesthetic in on this side.

The catheters contain 20 individual electrodes

which will allow the electrical activity inside his heart

to be recorded in minute detail.

Now, just going to leave that to work for a little while as well.

Before his treatment begins, whilst wired up,

he has agreed to watch two short videos for Peter's experiment.

I'll start this dot moving around on the screen and if you can just...

This first video is designed to relax the patient,

and give a measurement of his heart without emotion.

And your monitoring the heart through that equipment?

The recordings will give the electrical behaviour

on the right side of the heart and the left side of the heart

along with blood pressure and the motion of the breathing.

So you have a very clear picture

-of how his heart is reacting to watching that film?

-Yes, in detail.

The patient is then shown a dramatic scene

from the Hollywood movie Vertical Limit,

which Peter has specially selected

to produce a strong emotional response.

And this is a little scene where

there's a group of climbers on a cliff,

and the rope is pulling out of the cliff

and the only way they can save themselves is by

reducing the weight on the rope. That means cutting the bottom person loose

and the bottom person is the father of the family which are on the rope.

-No.

-There's too much weight. One cam will never hold us.

You have to cut me loose.

Everybody knows that when you're excited or stressed,

your heart beats faster.

But Peter is interested in something far more intricate

than what happens to just the heart rate.

His measurements are designed to detect how

the actual beat of the heart itself can change in response to emotion.

If you don't do this, I'll pull everybody down and everybody'll die!

-It'll hold!

-Shut up, Annie!

The heartbeat is controlled by electrical waves

which travel across the heart,

causing the muscle to contract and relax.

Is it working, your experiment?

It's getting very exciting. What we're finding is that

when the person watches something that is boring and bland,

-nothing happens to the measurements.

-Right.

When they watch something exciting

or in this case, a really dramatic scene...

-No!

-It's one dead or three, Peter! Understand?

-Don't make him do this!

..then there's a measurable change

in the way that the electrical waves circulate through the heart.

Peter believes that in people with more vulnerable, damaged hearts,

this effect could be enough to trigger the heart's rhythm

to break down entirely.

-We're going to die!

-No!

-Annie, we're all going to die!

Just cut it, Peter! Just cut it!

It does sound like you're...

you're re-establishing the connection of emotions to the heart.

Well, I think everybody's sort of concept of the heart

is that it's a pump

and when you, when you, for example, have death,

that the heart stops and that it may cease to function properly

because instead of beating nice and synchronously,

the rhythm changes and the activation waves go all irregular

and it becomes discoordinate and the function goes.

And you're saying it can be emotions that can trigger that.

And this is the sort of thing that can do that

in an already-compromised heart.

-I would stress that this only happens in very, very poorly hearts.

-Right.

But...it sounds, and forgive me if I'm wrong,

but it sounds as if you're tiptoeing back towards

people who talk about, "He died of a broken heart."

-Exactly.

-Really?

-Yes.

Well, I think there's a whole mass of anecdotal evidence

but anecdotal evidence is anecdotal

and it doesn't have scientific credibility.

What we're trying to do now

is to give, I suppose, scientific credibility

to what people have known for thousands of years.

Yes, yes.

-I'm glad you're doing it!

-Well, not before time.

I've always felt

that poetry doesn't work unless it has one foot in reality.

And now science is suggesting

that the poetry of the heart might hold some truth.

It does seem to me we've already come quite a long way from Descartes

where the heart suddenly was, there was no emotion at all,

it was completely stripped of any emotion. It seems to me that

science is beginning to put some of that emotion back.

It's not quite, you know, the seat of the soul...

..but it's not an unemotional thing either.

But science is not just returning emotion back to the heart.

In other fundamental ways,

it is rethinking the whole relation between heart and mind,

emotion and reason.

'I've come to Oxford, to meet Professor David Paterson,

'who is at the forefront of this new revolution.'

-So welcome to Merton College.

-Thank you very much.

My research really straddles

between these two organs, the brain and the heart,

because historically, they've always been viewed as islands to themselves.

Fantastic. I want to hear about this.

Professor Paterson's research

is helping challenge the traditional view

of how the heart and brain work together.

The brain is made up of billions of neurons

and is able to influence the heart rate

by sending messages down the different nerve fibres,

the wiring of the human body.

When the heart receives signals from the brain

through the sympathetic nerves, it pumps faster.

And when it receives signals through the parasympathetic nerves,

it slows down.

On its own, this appears to fit

with the picture of the heart enslaved to the brain.

But the true relationship between the two organs is far more nuanced.

If you look at a heart...

You happen to have one with you.

And I happen to have a heart in my pocket,

which all good physiologists carry around with them,

but the traditional anatomical view of the nervous system and the heart

is that you have these major two nerves coming down from the brain.

-Which is just telling the heart what to do.

-Speed up, slow down.

-Yeah.

But in the heart itself,

you have around 10,000 or so very specialised neurons that sit there,

and these predominantly lie around the right atrial surfaces...

-Not just nerve cells?

-Not just nerve cells.

-You're using neuron advisedly.

..that form networks.

-OK.

-And that begs the question...

-Begging many questions!

-Well, what is their role?

Why are they there? Why has nature put them there?

Yes. Why are you the first person to tell me this?

-Well, it's not established in textbooks.

-But why not?

Well, I think the textbooks need to be rewritten

and they are being rewritten.

It's astonishing to think that neurons,

the very cells that make up the brain in our heads

and give us the ability to think,

are also present within the heart.

And there are so many of them

that these neurons have been called by those who study them

the heart's little brain.

Much about the heart's neurons is still unknown,

but one thing is clear -

that the brain in our heads doesn't simply control the heart,

but works in partnership with it.

Right.

This is a little bit different from college.

What you're looking at is a section of tissue taken from a rat's heart.

It contains most of the neurons that make up the heart's little brain.

The tissue is being kept alive by a solution of nutrients

and the bubbling oxygen

and if you look closely,

you can see that the tissue is beating of its own accord.

So this is a, just a little bit of the right atrial tissue

and inside, there are these neurons

and in fact, what we see here is that the tissue is beating by itself.

So is that, it looks like a heartbeat?

That's right, it's very similar. It's an actual contraction

so this is beating at about 180, almost 200 beats per minute.

Professor Paterson is going to show me

that by sending an electric signal to the heart's little brain,

that little brain can then slow down the heart rate.

This mimics how the brain in our heads asks the heart to slow down,

a process that relies on the neurons in the heart.

We've got a very small electrode sitting over by these neurons,

so we're going to excite them.

I get to press the button?

-And then look at the trace.

-I'm quite nervous about it.

-Here, see?

-Oh, my God!

-See that?

-See, it's slowed down?

-That's dramatic!

So what you're doing is, you're activating the neurons.

So I sent it a little mental signal?

-Yeah, a mental signal.

-It's going further down.

Yeah, because you're maintaining the stimulation.

-I'm going to switch it off.

-So turn it off.

And then...

The parasympathetic nervous system is now back off.

-And back it's coming.

-And up it comes again. Isn't that...

-It's fast, too.

-It's very quick.

-Look at that.

In fact, it happens within about a beat.

What we've done is completely taken the brain out of the picture.

-We've just electrically excited those neurons.

-Yes.

-So right down at the tissues...

-The neurons in the heart.

-And now they're taking over, they're doing it.

-They're taking over

and they're releasing the chemical messages to then slow the heart down.

So in a way, that's demonstrating

how much of that neural control is in the heart.

Is in the heart itself, because...

-We evidently don't have a brain, we have a small...

-Stimulator.

Small grotty-looking pile of simple electronics. That's not a brain.

-That's right.

-So the decision - using the word slightly metaphorically -

-is happening in there.

-It's happening in there, that's right,

-completely devoid of the essential nervous system.

-Wow.

-That's rather impressive. And it looks great.

-Yeah.

This shows the extent to which it is these neurons in the heart

that control what the heart does, not the brain.

Professor Paterson's work is revealing just how complex

the little brain in the heart really is.

See if we can see some of the heart cells beating.

-There!

-I saw them pulse there.

OK.

These are the neurons that make up the heart's little brain.

They live side-by-side with the cardiac muscle cells in the heart.

They really are a unit, then, aren't they? I mean, it's not just,

"Here's the heart doing everything the heart does

"and then we've got some neurons just watching what's going on."

-There's an active partnership here.

-No question about that.

We need to understand this. It's very poorly understood,

the detailed neurochemistry, the detailed electrophysiology.

We're only really starting to scratch the surface

of this network in the heart.

Gosh, we are a long way from just playing with the plumbing of a pump.

Much more complex than that.

I suppose I feel, I feel optimistic, having talked to Professor Paterson.

Because I do have to admit

that after the first day, I felt, I felt quite concerned.

We got such a telling-off that I thought,

"Maybe this film really has gone off in all the wrong direction.

"Maybe what we're trying to say is just silly."

But having talked to Professor Paterson,

I feel that there really is something important,

something scientifically true...

..but also something important that we are trying to say

and I feel good about that.

Modern science is now painting a picture of the heart

that I believe is much closer to how we really are.

The heart is a pump

that does respond when the brain asks it to,

but it is not enslaved to the brain.

Its relationship with the brain is more like a marriage,

living in partnership with each dependent upon the other.

But most importantly,

it seems to me science is now restoring to the heart

something of what rightfully belongs to it - our emotions.

Because it is not just thoughts that govern our lives.

Well, a couple of years ago, my wife became...

..profoundly depressed, clinically depressed.

And...

The person I fell in love with,

the person who I've lived with my adult life, is...

..is gone.

And it...

And it's...

It's a very painful thing, not just rationally painful...

I...

I never knew what that phrase, "my heart ached" or "my heart broke,"

it was just poetry for me, but it isn't any more.

I just suddenly was confronted by a question I'd never thought about,

about this relationship between...

The life of my heart,

the emotional life, the emotional centre of it,

which when it was fine, I never thought about,

I just took it for granted.

But something went wrong with my...

..wife's mind.

And, uh...

It's hurting my heart.

Can you make sense of the most emotionally difficult things in your life

simply by having a rational think about them?

This is what I've tried for the last two years,

and I can tell you, it doesn't work.

When, you know, this illness took Sarah away from me,

I sort of felt, well, it's so easy for the rational mind to say,

"Look, it's a rational world and we have rational thoughts

"and you keep those silly emotions at bay because they get in the way,"

but I don't have a clear...

I can't sum it up in two or three rational sentences.

But what makes you think you have to sum it up

in two or three rational sentences?

I don't know. That's a good question.

I don't know, I thought I should be able to, that there would be a...

Well, you're talking about

the most mysterious and complicated things that we experience

and...it's unkind to yourself

to think you would be able to sum that up in two or three sentences,

and indeed, it's not likely

that we would ever be able to sum up such things in that way.

I'm not going to find the way forward through an emotional storm

just by consulting the rational part of my mind.

I feel there's a whole other side to me,

which unless I give it a voice,

unless I listen to what it's telling me,

I'm not going to make it through.

And that's my heart.

But what does it mean to follow your heart?

I would like to think that the heart's influence

is as it has always been imagined by the poets.

That is makes us kinder, more compassionate people.

The final thing I want to explore about the heart

is how it can affect the mind.

In this experiment, images of frightened and calm faces

are being shown to me for split seconds.

Some in time with my heartbeat...

..and others out of time.

And I'm being asked to judge the intensity of the face.

This research is being carried out by Professor Hugo Critchley

and Dr Sarah Garfinkel at Brighton and Sussex Medical School.

-And how was that?

-'Stressful.'

Just take this off...

'No, it was quite weirdly intense.'

The second one started out fine...

-Yeah.

-And then got more worrisome.

OK, so we can come through here.

'What Hugo and Sarah are interested in'

is whether my brain experiences the faces differently

if they are shown to me in time with my heart.

This is your intensity ratings here.

-Right.

-And if fear faces were out of sync with your heart,

then you rated them as less intense.

-Right.

-If they were in sync with your heart,

then you rated them as more intense

and if you look at the other categories,

there was no difference of heartbeat.

-Neutral faces, it made no difference.

-It's the same.

-Exactly.

So the only time the heart was influencing your emotion ratings

-was when it was an explicit fear face.

-Right.

The results show

that when frightened faces were shown in time with my heartbeat,

I perceived them to be more frightened.

In other words, how my mind processed the fear faces

was affected by my heart.

-So, if we look at it...

-'From the brain scans,

'Hugo and Sarah are able to pinpoint the exact region of the brain

'that is affected by the heart.'

When your brain is processing fear in time with your heart beating,

we get this great mass of activity

in a region of the brain called the amygdala, which is known...

-Ah, yes.

-..to be the threat processing region of the brain,

just showing that the amygdala processes fear

in conjunction with the heart's signalling when it's beating.

Does that light up more when it's in sync with the heart

-than if it's not?

-Absolutely.

-Really?

-Yeah.

'But the experiment had an unexpected effect on me.'

Although I was being shown frightened faces,

it was not fear that I felt, but concern.

The faces were reminding me of someone I care about.

It was rather an intense experience, because I was looking at those faces

and feeling worried about those people,

not those people, I was looking at those faces and it was reminding me

of someone I care about and thinking, thinking about their...

..their pain or their sadness,

and that was what made it very intense for me,

but is that really what was going on?

Certainly, the way we interpret other people's emotions

is very much influenced

by our capacity to embody their emotional state.

If I see someone...in pain, something bad happens to them,

you're saying that my heart helps me to create some...

-Understanding of them.

-Part of that feeling.

From an emotional level, yeah, absolutely.

So certainly, this emotional system

is very much tuned into emotions like compassion for other people,

empathising with people's emotional states,

as well as producing the kind of shared joy and positive emotions

-that, you know, that bond us socially.

-That's, that's fantastic.

So that, you know, that phrase, "I feel for you" - you do.

You're telling me my heart is able to make that true, that statement.

The heart is certainly a big component.

I consider the heart to be

one of the main channels of that kind of information.

It seems that the heart beats not just with our own emotions,

but also with other people's.

It is our hearts, working in tandem with our brains,

that allow us to feel for others.

And painful though it might be at times to experience that compassion,

it is ultimately what makes us human.

For me, compassion is the heart's gift to the rational mind.

The things I hoped would be true about being human,

I'm reassured that they are true.

And the things I hoped would be

how we work and the kind of creatures we are, they really are,

you can experimentally see that IS how we work

and it DOES underpin the thing about us

which I personally feel is what makes us a worthwhile species,

that we can feel compassion for other people.

I'm not really hugely impressed that we can...build faster jets,

but that we are made in such a way

that we can feel someone else's pain and feel compassion for them...

I think that's fantastic.

In the end, this battle between the head and the heart

to decide what's the best part of us leaves no triumphant victor.

In reality, we need both.

The heart may be more than just a pump.

It may help us to care for one another,

but it is stuck in the present.

It is only the brain that can imagine a different world

and invent it,

but if we want that world to be a better world,

then surely we also have to listen to the heart.

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