0:00:03 > 0:00:04My name is David Malone.
0:00:04 > 0:00:08I am a science documentary filmmaker.
0:00:08 > 0:00:11And I have come to Papworth Hospital in Cambridgeshire.
0:00:11 > 0:00:13It's the first time you've been in theatre?
0:00:13 > 0:00:16Yes. I don't know what I'm doing, but I'm good at following orders.
0:00:16 > 0:00:20I'm here at the invitation of consultant surgeon Mr Francis Wells,
0:00:20 > 0:00:24who is going to allow me to watch him perform open-heart surgery.
0:00:24 > 0:00:27He's got a leaky aortic valve.
0:00:27 > 0:00:30I've always wanted to see the beating human heart.
0:00:30 > 0:00:33That thing within us that keeps us alive.
0:00:35 > 0:00:39You'll see when you get in here how colourful the human body is. It's amazing.
0:00:39 > 0:00:43You sound like it's never lost its thrill for you.
0:00:43 > 0:00:46No, not at all.
0:00:46 > 0:00:49The heart is unlike any other organ in the human body.
0:00:49 > 0:00:53It has its own rich language and poetry.
0:00:58 > 0:01:03Throughout history, it has been a potent symbol in our religion,
0:01:03 > 0:01:06literature and philosophy.
0:01:06 > 0:01:09It has been seen as the site of our emotions.
0:01:09 > 0:01:11The very centre of our being.
0:01:19 > 0:01:24But modern medicine has come to see the heart as just a pump.
0:01:24 > 0:01:27A brilliant pump, but nothing more.
0:01:27 > 0:01:31And we view ourselves as ruled by our heads
0:01:31 > 0:01:33and not our hearts.
0:01:34 > 0:01:38- So, that's the valve actually going into place?- Going in, yes.
0:01:39 > 0:01:45And yet there's something about the heart that makes me wonder
0:01:45 > 0:01:47whether there is more to it than this.
0:01:47 > 0:01:49You open up this body that's lying still
0:01:49 > 0:01:54and inside there's this other creature, struggling away.
0:01:54 > 0:01:59So I want to explore the story of the heart.
0:01:59 > 0:02:03How it came to lose out in the age-old battle of hearts and minds
0:02:03 > 0:02:06and ask whether with the help of modern science,
0:02:06 > 0:02:09the heart may reclaim its traditional place
0:02:09 > 0:02:11at the centre of our lives.
0:02:11 > 0:02:14There's the heart working. All back in one piece.
0:02:23 > 0:02:27Open-heart surgery is one of the great triumphs of modern medicine.
0:02:27 > 0:02:32I have to tell you, it's the movement which I find extraordinary.
0:02:34 > 0:02:37The liver sits there looking ugly. The spleen sits there looking ugly.
0:02:37 > 0:02:41The bowel sits there smelling awfully.
0:02:41 > 0:02:43- The brain sits there... - Doing nothing at all.
0:02:45 > 0:02:47To perform operations like this,
0:02:47 > 0:02:50surgeons can't help but view the heart as a machine.
0:02:50 > 0:02:54Something that can be fixed when it goes wrong.
0:02:55 > 0:02:59But for Mr Francis Wells, one of Britain's leading heart specialists,
0:02:59 > 0:03:04this is a machine that can still inspire wonder.
0:03:04 > 0:03:07- What we see is a bit of muscle contracting here.- Yes.
0:03:07 > 0:03:10What's going on inside the cells at a metabolic level
0:03:10 > 0:03:12is immensely complicated.
0:03:12 > 0:03:15You work with these hearts everyday.
0:03:15 > 0:03:17You see them, the mechanical side of human nature.
0:03:17 > 0:03:20Yes. There is a mechanistic side to it
0:03:20 > 0:03:22which is easily appreciable
0:03:22 > 0:03:24and learnable and correctable.
0:03:24 > 0:03:30But, um...you rapidly appreciate that it isn't just mechanical.
0:03:30 > 0:03:33Biological structures and tissues
0:03:33 > 0:03:36are beyond mechanical.
0:03:36 > 0:03:38It has a life. It has a momentum.
0:03:40 > 0:03:43For Mr Wells, the heart's extraordinary biology
0:03:43 > 0:03:45gives it a beauty all of its own.
0:03:47 > 0:03:50He sees no need to romanticise the role of the heart
0:03:50 > 0:03:54beyond its vital function as a pump.
0:03:54 > 0:03:58- Thank you. It was a privilege. - No, not at all.
0:03:58 > 0:04:02I suppose what I'm looking at is, how much of that wonderful poetry,
0:04:02 > 0:04:05the romantic poetry of the heart,
0:04:05 > 0:04:07- is just poetry...- All of it.
0:04:07 > 0:04:11And how much of it is a poetic
0:04:11 > 0:04:13report about something that...
0:04:13 > 0:04:16You've answered the question yourself
0:04:16 > 0:04:18because you made the point at the beginning
0:04:18 > 0:04:21- that you'd never seen a human heart before.- No.
0:04:21 > 0:04:26And I would bet you that 99.99% of the poets of the past
0:04:26 > 0:04:28have never seen a human heart before.
0:04:28 > 0:04:32We all like this emotional interplay.
0:04:32 > 0:04:35But the heart is a bunch of muscles
0:04:35 > 0:04:41with some nerves that stimulate it.
0:04:41 > 0:04:43And it has some chemical receptors
0:04:43 > 0:04:45which allow it to respond
0:04:45 > 0:04:47to chemical and neurological stimuli.
0:04:47 > 0:04:49Whilst we all want to think of it
0:04:49 > 0:04:55as being this incredibly fanciful structure, and we all do,
0:04:55 > 0:04:58in reality, it's a pump.
0:04:58 > 0:04:59That's what it does.
0:04:59 > 0:05:02I know I can take the heart out and you can still fall in love.
0:05:02 > 0:05:05I can take the heart and the liver out and you'll still fall in love.
0:05:05 > 0:05:09I take the heart, liver, lungs and bowel out, you'll still fall in love.
0:05:09 > 0:05:11Well, that's useful to know in an emergency.
0:05:11 > 0:05:13It's true. We've done it.
0:05:14 > 0:05:19But if I asked myself what part of me feels love for my family,
0:05:19 > 0:05:22I would say I feel it in my heart.
0:05:22 > 0:05:27I love my three sons with all my heart.
0:05:29 > 0:05:35And when I first met my wife Sarah, my heart skipped a beat.
0:05:35 > 0:05:38This is the familiar language of the heart.
0:05:38 > 0:05:42One that talks about being broken-hearted.
0:05:42 > 0:05:44Or your heart swelling with joy.
0:05:47 > 0:05:49The whole reason we're making the film
0:05:49 > 0:05:52is to explore that poetic language of the heart.
0:05:52 > 0:05:54His heart swelled, his heart jumped,
0:05:54 > 0:05:57his heart burst, his heart broke.
0:05:57 > 0:05:58I suppose what we're asking is,
0:05:58 > 0:06:03how much is that language just poetry
0:06:03 > 0:06:06and how much of that poetic language
0:06:06 > 0:06:09is an accurate description
0:06:09 > 0:06:12of something which is true, just said poetically?
0:06:12 > 0:06:14And I don't know yet.
0:06:14 > 0:06:19Why this matters is because I believe our view of the heart,
0:06:19 > 0:06:21in some fundamental sense,
0:06:21 > 0:06:25is a reflection of how we see ourselves.
0:06:28 > 0:06:30The problem I have with the modern view
0:06:30 > 0:06:34we have of ourselves and our world
0:06:34 > 0:06:38is not so much that it's soulless as heartless.
0:06:38 > 0:06:42We're encouraged to view ourselves as if we live just in our heads.
0:06:42 > 0:06:44As if our brains rode around in our bodies
0:06:44 > 0:06:46the way that we drive our cars.
0:06:47 > 0:06:50And for me, that means we...
0:06:50 > 0:06:52we relegate everything that we feel
0:06:52 > 0:06:57as if somehow our emotions were less important
0:06:57 > 0:07:00than our thoughts.
0:07:01 > 0:07:04Yet for much of human history,
0:07:04 > 0:07:06we saw that what made us wonderful creatures
0:07:06 > 0:07:10was not our brain, but our heart.
0:07:11 > 0:07:13But was this very different way
0:07:13 > 0:07:16in which we used to see ourselves so misguided?
0:07:31 > 0:07:35Richard Parkinson is a curator at the British Museum
0:07:35 > 0:07:40and is showing me a papyrus over 4,000 years old from ancient Egypt.
0:07:43 > 0:07:47This is the famous papyrus of Ani,
0:07:47 > 0:07:50which is part of one of the funeral papyri.
0:07:50 > 0:07:53For the ancient Egyptians,
0:07:53 > 0:07:56the heart was the most important organ in the human body.
0:07:56 > 0:08:01It's very much the symbol of the mind, the emotions, the character.
0:08:01 > 0:08:05Everything is represented by that particular organ.
0:08:05 > 0:08:07And did the ancient Egyptians
0:08:07 > 0:08:11- believe that was the centre of their being?- It seems to be that way.
0:08:11 > 0:08:14All the language refers to the heart in descriptions of character.
0:08:14 > 0:08:17If you're greedy, you're grasping of heart.
0:08:17 > 0:08:20If you're patient, you're enduring of heart.
0:08:20 > 0:08:24The heart is the one thing that really anchors ideas of personality.
0:08:25 > 0:08:29The papyrus depicts a scene called the weighing of the heart.
0:08:29 > 0:08:33The ancient Egyptians believed a person would only pass into the afterlife
0:08:33 > 0:08:37if their heart balanced against the feather of truth.
0:08:37 > 0:08:40If not, the heart would be eaten by the devourer
0:08:40 > 0:08:43and they would become nothing.
0:08:43 > 0:08:45Why balanced against truth? I mean, it's lovely.
0:08:45 > 0:08:50Truth is the...Egyptian way of life.
0:08:50 > 0:08:54It's something like justice, truth, order
0:08:54 > 0:09:00in society and in the personal life, in the cosmic life, as well.
0:09:00 > 0:09:06- And your heart has to be exactly in tune with truth.- With that truth.
0:09:06 > 0:09:09And so, above the heart in the papyrus
0:09:09 > 0:09:13is the famous heart spell, which just begins here.
0:09:13 > 0:09:16You can see the sign of the heart there. My heart.
0:09:16 > 0:09:19- Can you read that? - It's standard Middle Egyptian.
0:09:19 > 0:09:21He addresses his heart. "My heart of my mother.
0:09:21 > 0:09:25"Do not stand up against me as a witness
0:09:25 > 0:09:29"and oppose me in front of the company of gods."
0:09:29 > 0:09:31- He's talking to his heart?- Yes.
0:09:31 > 0:09:36- Keep the heart quiet. Don't let it give the game away. - Because the heart tells the truth?
0:09:36 > 0:09:40The heart might tell the truth if he's encouraged too much by the judges.
0:09:40 > 0:09:43The heart, physiologically, it does tells the truth.
0:09:43 > 0:09:46In the sense that when you try to lie,
0:09:46 > 0:09:50your brain says, "Let's keep calm. Let's not give anything away."
0:09:50 > 0:09:52But your heart starts thumping, you start sweating.
0:09:52 > 0:09:55So the heart, it really is the organ
0:09:55 > 0:09:59which can't help but give you away if you're not careful,
0:09:59 > 0:10:03- which makes that practical admonition so lovely.- Absolutely.
0:10:03 > 0:10:05It must have been a very well-fed monster.
0:10:05 > 0:10:08Some of them look quite eager.
0:10:10 > 0:10:13The ancient Egyptians did not understand
0:10:13 > 0:10:16that the heart pumps blood around the body,
0:10:16 > 0:10:20but they did recognise a quality about the heart just as profound.
0:10:22 > 0:10:26That when we tell lies, it is the beating of our hearts that can betray us.
0:10:29 > 0:10:33I have to say, I like the ancient Egyptians. I like the fact that...
0:10:34 > 0:10:37..they see the heart as being connected with truth.
0:10:37 > 0:10:40Not something airy-fairy like love, but truth.
0:10:40 > 0:10:44That it simply tells you the truth about how you are,
0:10:44 > 0:10:47what you are feeling, what you think.
0:10:47 > 0:10:50And they were right.
0:11:03 > 0:11:06As the earliest scientists began to explore the heart,
0:11:06 > 0:11:10what was seen seemed to reinforce the notion
0:11:10 > 0:11:13that this organ of truth and emotion
0:11:13 > 0:11:17was also at the centre and beginning of life.
0:11:20 > 0:11:23It was the Greek philosopher Aristotle who first glimpsed
0:11:23 > 0:11:28this remarkable sight of the embryonic beating heart.
0:11:30 > 0:11:34For Professor Thomas Brand, developmental biologist at Imperial College London,
0:11:34 > 0:11:39what amazed Aristotle has lost none of its magic.
0:11:39 > 0:11:43- How old is this one?- Three days.- And you can see it fills up and empties.
0:11:43 > 0:11:45So you get to see the whole pulsing.
0:11:45 > 0:11:48Yes. You see the entire cardiac cycle happening.
0:11:48 > 0:11:51Here we have the eye, here the ear.
0:11:51 > 0:11:54And here the future jaw.
0:11:54 > 0:11:56Aristotle could see that the heart
0:11:56 > 0:11:59is one of the very first organs to form in the embryo.
0:11:59 > 0:12:02And he recognised that the embryo could only develop
0:12:02 > 0:12:04with a healthy beating heart.
0:12:04 > 0:12:07It was vital to life.
0:12:07 > 0:12:10Certainly, Aristotle was the first one to realise
0:12:10 > 0:12:14that there is something like, er...
0:12:14 > 0:12:18something forming in the yolk.
0:12:18 > 0:12:21It was quite an accomplishment
0:12:21 > 0:12:23to see the heart all of a sudden there.
0:12:23 > 0:12:27What did he conclude when he saw this? Did he...?
0:12:27 > 0:12:30Well, he saw that the heart is actually forming first
0:12:30 > 0:12:34and then from the heart, all the other organs
0:12:34 > 0:12:38are derivatives of, or actually used by the heart.
0:12:38 > 0:12:41- Really?- And this is a concept
0:12:41 > 0:12:44that has some truth to it.
0:12:44 > 0:12:46Right from the start of life,
0:12:46 > 0:12:51the heart is driving the development.
0:12:51 > 0:12:54Yeah. The heart is very important. It's very essential.
0:12:54 > 0:12:57If an embryo like a chick embryo has no heart,
0:12:57 > 0:12:59it would stop developing right way.
0:12:59 > 0:13:01This is a chick, but would we see something similar
0:13:01 > 0:13:04if you were looking at, say, I don't know,
0:13:04 > 0:13:07a dog or an ape or a human?
0:13:07 > 0:13:09They would all look the same way.
0:13:09 > 0:13:14So this is a very basic blueprint that life has found.
0:13:14 > 0:13:16Correct. If you would see...at his stage,
0:13:16 > 0:13:18if you would look at any other embryo,
0:13:18 > 0:13:20they would look almost the same way.
0:13:22 > 0:13:24Aristotle had established the heart
0:13:24 > 0:13:27not just as the seat of our emotions
0:13:27 > 0:13:28and the teller of truth,
0:13:28 > 0:13:32but also the force in the body that keeps us alive.
0:13:35 > 0:13:39But this was also the time of the birth of philosophy
0:13:39 > 0:13:43and a view began to emerge that thoughts were different to emotions.
0:13:46 > 0:13:50That each belonged to different parts of our bodies.
0:13:50 > 0:13:52Our heart, and our brain.
0:13:55 > 0:13:59The idea was promoted in the writing of the Roman physician Galen.
0:14:01 > 0:14:04For Galen, the head is associated with reason.
0:14:04 > 0:14:09The abdomen is associated with the heart and with passion.
0:14:09 > 0:14:12And the lower regions are associated with procreation.
0:14:12 > 0:14:16So that is his way of understanding how the body functions.
0:14:16 > 0:14:19That's the first time we really have a separation
0:14:19 > 0:14:23between the emotional heart and the rational brain.
0:14:24 > 0:14:29Galen's views dominated western thought for over 1,000 years.
0:14:29 > 0:14:34The heart reigned unchallenged as the seat of our emotional lives.
0:14:34 > 0:14:36An idea expressed in art,
0:14:36 > 0:14:39literature and religion.
0:14:41 > 0:14:43But in the 17th century,
0:14:43 > 0:14:46our entire understanding of the heart changed.
0:14:49 > 0:14:52The English physician William Harvey made a discovery
0:14:52 > 0:14:54that would give a new role to the heart.
0:14:56 > 0:14:59Harvey was interested in how blood moves through the body.
0:15:02 > 0:15:06According to Galen, blood flowed like the tide,
0:15:06 > 0:15:08ebbing back and forth.
0:15:08 > 0:15:11There was no circulation.
0:15:11 > 0:15:14The arteries and veins were entirely separate.
0:15:15 > 0:15:18Harvey showed this was wrong.
0:15:18 > 0:15:23Today, we're going to look at the small blood vessels in your fingers.
0:15:23 > 0:15:27Dr Art Tucker is a clinical scientist
0:15:27 > 0:15:30at St Bartholomew's Hospital in London.
0:15:30 > 0:15:34He's able to show me what Harvey knew must be true,
0:15:34 > 0:15:36but was never able to see with his own eyes.
0:15:37 > 0:15:40That if the blood circulated,
0:15:40 > 0:15:43then the blood that flowed out must somewhere turn back.
0:15:43 > 0:15:47The arteries must become veins.
0:15:47 > 0:15:48And there they are.
0:15:48 > 0:15:51- Those little loops? - Those little loops.
0:15:52 > 0:15:54These beautiful ghostly figures
0:15:54 > 0:15:57are the capillaries in my fingernail.
0:15:57 > 0:16:00It's in the capillaries that arteries turn into veins
0:16:00 > 0:16:04and blood begins its return trip back to the heart.
0:16:04 > 0:16:07- I can see something going around. - That's blood.
0:16:07 > 0:16:09- Am I really seeing that?- Yes.
0:16:09 > 0:16:13Even after...I've been doing this nearly 20 years,
0:16:13 > 0:16:16seeing these always excites me.
0:16:16 > 0:16:19It's fantastic seeing...
0:16:19 > 0:16:22- suddenly seeing them...they seem to fill up.- Yep.
0:16:22 > 0:16:25- So you see that...? - Whoa! I saw it zip around there.
0:16:25 > 0:16:27And this, in one aspect, truly demonstrates
0:16:27 > 0:16:30what Harvey was trying to say.
0:16:30 > 0:16:33In that the blood flows in a circulatory path
0:16:33 > 0:16:37rather than flowing, as Galen said, like the tide, in and back.
0:16:37 > 0:16:42And if you look carefully, the blood flows up one side...
0:16:44 > 0:16:47..around the loop and then returns.
0:16:47 > 0:16:50That blood is on the return journey back to the heart and lungs,
0:16:50 > 0:16:54where the carbon dioxide will be removed
0:16:54 > 0:16:55and the oxygen will be replenished.
0:16:58 > 0:17:02Harvey goes down in history as the man who first realised
0:17:02 > 0:17:06that the same organ understood to be the centre of our emotions
0:17:06 > 0:17:08also pumps blood around the body.
0:17:14 > 0:17:17For Harvey, his discovery did not diminish the heart,
0:17:17 > 0:17:20it added to its grandeur.
0:17:21 > 0:17:24But the time in which he lived, the dawn of the mechanical age,
0:17:24 > 0:17:28interpreted his discovery very differently.
0:17:29 > 0:17:32In the mind of one man in particular,
0:17:32 > 0:17:35the French philosopher Rene Descartes, a radical thought took hold.
0:17:37 > 0:17:41Descartes was in love with the mechanical and the rational.
0:17:43 > 0:17:47And it seemed only natural to him to re-imagine the human body and mind
0:17:47 > 0:17:52in terms of the cogs and wheels of the early industrial revolution.
0:17:54 > 0:17:58I think for Descartes, the notion of metaphor is very important.
0:17:58 > 0:18:01Because he wants this entirely mechanical account of the world about us
0:18:01 > 0:18:04and he wants to use mechanical analogies within that.
0:18:04 > 0:18:07He wants to say that things are like pumps,
0:18:07 > 0:18:09they're like engines, they're like clocks.
0:18:09 > 0:18:13Because these are the sorts of things that fit well with his notion of the world.
0:18:15 > 0:18:20Descartes' ideas recast the human body as an elaborate machine
0:18:20 > 0:18:23with the rational mind now in command.
0:18:26 > 0:18:29The stomach and intestines as some sort of refinery
0:18:29 > 0:18:32where fuel is processed.
0:18:34 > 0:18:38And the heart...no longer the seat of emotion
0:18:38 > 0:18:40nor truth teller.
0:18:40 > 0:18:42Now nothing more than a mechanical pump.
0:18:43 > 0:18:47And it was Harvey's discovery seen in the capillaries
0:18:47 > 0:18:50that made this view of the heart seem indisputable.
0:18:53 > 0:18:57Zealous believers of Descartes' ideas
0:18:57 > 0:19:00could even dismiss the cries of pain from tortured animals
0:19:00 > 0:19:05as nothing more than the creaking of animal clockwork.
0:19:06 > 0:19:11They were becoming just like their machines, cold and mechanistic.
0:19:11 > 0:19:13Devoid of feeling.
0:19:15 > 0:19:18If you want to find one moment where the new view replaced the old,
0:19:18 > 0:19:22it's when Harvey's work seemed to give licence
0:19:22 > 0:19:24to applying this mechanical metaphor,
0:19:24 > 0:19:27not just to the outside world, but to us, as well.
0:19:27 > 0:19:31Which was ironic because Harvey himself didn't like this new view.
0:19:31 > 0:19:33And that in itself is quite telling.
0:19:33 > 0:19:37In Harvey, it's almost as if you can see how the heart
0:19:37 > 0:19:38was unable to defend itself
0:19:38 > 0:19:41against the triumph of the rational mind.
0:19:44 > 0:19:47That triumph might have been lessened
0:19:47 > 0:19:50had Harvey and the others of his time
0:19:50 > 0:19:52known more about how the heart pumps blood.
0:19:54 > 0:19:57In particular, had they known about a discovery
0:19:57 > 0:19:58made over a century earlier
0:19:58 > 0:20:02that painted a picture of the heart very different
0:20:02 > 0:20:06from the crude mechanical pumps of the industrial age.
0:20:14 > 0:20:16In the Royal library at Windsor Castle,
0:20:16 > 0:20:19curator Martin Clayton is showing me
0:20:19 > 0:20:23beautiful anatomical drawings by Leonardo da Vinci.
0:20:24 > 0:20:28Drawings that were neglected for almost 400 years after his death.
0:20:30 > 0:20:35They document da Vinci's remarkable understanding of the heart.
0:20:35 > 0:20:39These are drawings from almost the end of Leonardo's anatomical career.
0:20:39 > 0:20:41Done about 1512, 1513.
0:20:41 > 0:20:44So Leonardo was 60 years old or thereabouts
0:20:44 > 0:20:47when he made these dissections.
0:20:47 > 0:20:49It was what Da Vinci discovered
0:20:49 > 0:20:52about how blood flows through the valves of the heart
0:20:52 > 0:20:54that was most important.
0:20:56 > 0:20:58In a remarkable experiment,
0:20:58 > 0:21:01Da Vinci constructed a glass model of the heart's aorta,
0:21:01 > 0:21:05the artery which takes blood away from the heart to the body.
0:21:06 > 0:21:11He deduced that as the blood flows through the valve into the aorta,
0:21:11 > 0:21:15it must make a beautiful swirling pattern called a vortex.
0:21:17 > 0:21:20And then he describes how he would pump water
0:21:20 > 0:21:24with a suspension of grass seeds through his glass model
0:21:24 > 0:21:26so he could observe what were vortices
0:21:26 > 0:21:30in this chamber now known as the sinus of Valsalva,
0:21:30 > 0:21:33just above the aortic valve.
0:21:33 > 0:21:37And he surmised that the purpose of these vortices
0:21:37 > 0:21:40was to open out the valves.
0:21:41 > 0:21:45This graceful pattern is called a ring vortex.
0:21:45 > 0:21:48Da Vinci understood that blood creates this shape
0:21:48 > 0:21:53as it flows through the valve into the heart's aorta.
0:21:53 > 0:21:56His key insight was that this swirling of the blood
0:21:56 > 0:22:00does not work against the heart, but with it.
0:22:00 > 0:22:05Helping close shut the flaps of the valve behind.
0:22:06 > 0:22:10The workings of the heart had a natural beauty.
0:22:10 > 0:22:14Totally unlike the crude mechanical pumps
0:22:14 > 0:22:16of the industrial revolution.
0:22:16 > 0:22:21Doesn't it strike you as one of those moments in history where if we'd gone that way,
0:22:21 > 0:22:24if someone had said, "Show me that again, Leonardo,"
0:22:24 > 0:22:27we would have had such a different view of what we meant by a pump.
0:22:27 > 0:22:34I think what people had in mind was the kind of drum with a stick that goes in and out, which...
0:22:34 > 0:22:37So when people said, the heart's the pump, that's what they had in mind.
0:22:37 > 0:22:43- And it's nothing like that! - Something so sympathetic to the structure of the heart.
0:22:43 > 0:22:47The awareness that it's not just an accidental form or a crude form.
0:22:54 > 0:22:58Da Vinci had realised how the movement of the heart
0:22:58 > 0:23:03and the flow of blood work in natural harmony with one another.
0:23:03 > 0:23:05First scan starting, David.
0:23:05 > 0:23:07OK.
0:23:07 > 0:23:09David, can you take a breath in, please?
0:23:09 > 0:23:12Using modern magnetic resonance imaging,
0:23:12 > 0:23:15it's possible to see in beautiful detail
0:23:15 > 0:23:19the way in which the blood flows through the heart.
0:23:19 > 0:23:22David, this is longer, it's about 20 seconds.
0:23:24 > 0:23:27ROBOTIC VOICE: Please breathe in. Breathe out.
0:23:27 > 0:23:30And hold your breath.
0:23:31 > 0:23:35Thank you, David. We're finished. Very good images.
0:23:35 > 0:23:37It's not always the case. Thanks.
0:23:37 > 0:23:41Dr Philip Kilner is a consultant in cardiac imaging
0:23:41 > 0:23:44at the Royal Brompton Hospital in London.
0:23:44 > 0:23:48- Is that me?- This is you, absolutely.
0:23:48 > 0:23:50- And, er...- Let's have a look.
0:23:50 > 0:23:53Oh, my God!
0:23:53 > 0:23:56We're looking from below, in this case, towards the head.
0:23:56 > 0:23:59That was my heart as it was beating a few minutes ago?
0:23:59 > 0:24:03- Absolutely. Yes. - Am I imagining...? I mean, I...
0:24:03 > 0:24:07I'm thinking that I can see all sorts of complications in the flow.
0:24:07 > 0:24:08- Is that real?- Yes, that's real.
0:24:08 > 0:24:11That gives you a fairly genuine impression of flow.
0:24:11 > 0:24:15It's averaged over a multiple heartbeat, so it's not quite real-time.
0:24:15 > 0:24:19And it's to do with the tuning of the magnet
0:24:19 > 0:24:21that you actually see dark blood joining it.
0:24:21 > 0:24:24But nevertheless, that blood is showing us...
0:24:24 > 0:24:28You can actually see how complicated the swirls are in there.
0:24:28 > 0:24:30- Yes.- It curls around, swirls here and then it's...
0:24:30 > 0:24:34What's interesting is that if you listen to somebody's chest,
0:24:34 > 0:24:37you can hear the heart sounds, often described as
0:24:37 > 0:24:40lub dup, lub dup.
0:24:40 > 0:24:42The timing of that is like this.
0:24:42 > 0:24:44Lub, dup.
0:24:44 > 0:24:46Lub, dup.
0:24:46 > 0:24:48- Right.- Lub, dup.
0:24:48 > 0:24:51The deeper sound, the lub, is the closure of the inflow valve.
0:24:51 > 0:24:55And the higher-pitched sound is the closure of the aortic valve.
0:24:56 > 0:25:01It opens and closes roughly every second, faster if you're exercising.
0:25:01 > 0:25:05- For my whole life?- Your whole life, day and night, non-stop.
0:25:05 > 0:25:08- Yes.- That's about a million times every ten days.
0:25:08 > 0:25:10What a piece of engineering!
0:25:10 > 0:25:12It's stunning.
0:25:14 > 0:25:17This beautiful three-dimensional scan of a patient's heart
0:25:17 > 0:25:21was made by a colleague of Philip's in the United States.
0:25:22 > 0:25:26The blue shows the blood depleted of oxygen
0:25:26 > 0:25:28coming back from the body
0:25:28 > 0:25:30through the heart on its way to the lungs.
0:25:30 > 0:25:34And the red and yellow shows the oxygenated blood
0:25:34 > 0:25:37coming back from the lungs,
0:25:37 > 0:25:40through the heart and back out to the body.
0:25:40 > 0:25:44And if I walk you around this image, if I tip it like this,
0:25:44 > 0:25:47we're looking as if from the left shoulder.
0:25:47 > 0:25:51And now you can begin to see vortices in the left atrium
0:25:51 > 0:25:53- are swirling around. - Oh, yes, you can!
0:25:53 > 0:25:58And in the left ventricle, swirling mainly around the anterior mitral leaflet.
0:25:58 > 0:26:01You can see it's coming in, shooting down here, curling around
0:26:01 > 0:26:05- and then is directed back out that way.- Yes. Absolutely.
0:26:05 > 0:26:09So the heart doesn't really have to shove the liquid
0:26:09 > 0:26:11in a way that the liquid doesn't want to go.
0:26:11 > 0:26:14The liquid is heading there because of the shape of the heart.
0:26:14 > 0:26:16To some extent, I think that's true.
0:26:16 > 0:26:18Especially unexercised, I believe that's true.
0:26:18 > 0:26:21It's halfway between engineering and art.
0:26:21 > 0:26:23There's a beauty to it.
0:26:23 > 0:26:25To imagine it all but in series,
0:26:25 > 0:26:31and simultaneously flowing day and night, non-stop,
0:26:31 > 0:26:33throughout your life.
0:26:33 > 0:26:37- That's the most beautiful thing I can imagine.- Yeah.
0:26:40 > 0:26:43It is almost as if the flow of blood
0:26:43 > 0:26:47has carved out the shape of the heart through evolutionary time.
0:26:47 > 0:26:50The chambers of the heart are shaped in such a way
0:26:50 > 0:26:56that the blood swirls around in the direction the heart requires.
0:26:56 > 0:27:01Even the vast loop made by the blood as it flows around the heart
0:27:01 > 0:27:04means that as the main pumping chamber recoils,
0:27:04 > 0:27:09this helps the upper chamber refill with the next batch of blood.
0:27:10 > 0:27:13And part of this astonishing beauty of the heart
0:27:13 > 0:27:17had been glimpsed by Leonardo da Vinci.
0:27:17 > 0:27:20When you look at these two pictures,
0:27:20 > 0:27:24what you see here is the world of Leonardo or Shakespeare.
0:27:24 > 0:27:27This is the beginning of modern science.
0:27:27 > 0:27:31Thrilled at exploring the nature of being human.
0:27:32 > 0:27:35A couple of centuries later, it's completely changed.
0:27:35 > 0:27:38Here you have our culture,
0:27:38 > 0:27:40thrilled with exploring the world
0:27:40 > 0:27:43of gears and cogs and pulleys and ratchets
0:27:43 > 0:27:48and re-imagining us as if that's what we were.
0:28:02 > 0:28:05Mechanising the world has brought great benefits to human kind.
0:28:05 > 0:28:10We have built vast cities, industry and advanced technology.
0:28:12 > 0:28:15But mechanising the heart has, I believe,
0:28:15 > 0:28:19done untold damage to how we see ourselves.
0:28:23 > 0:28:26This tendency to see things in mechanical terms
0:28:26 > 0:28:30is something that psychiatrist Doctor Iain McGilchrist
0:28:30 > 0:28:33has spent 20 years thinking and writing about.
0:28:33 > 0:28:36That machine metaphor, it does do a lot.
0:28:36 > 0:28:38I mean, it has done a lot.
0:28:38 > 0:28:43We've built a mechanical world full of flashing lights and things that whizz around.
0:28:43 > 0:28:46It's enormously successful at doing certain things.
0:28:46 > 0:28:47And that's very seductive.
0:28:47 > 0:28:51But what it's not good at is describing...what we are.
0:28:51 > 0:28:54I mean, it can describe really well
0:28:54 > 0:28:57the mechanical pumping aspects of the heart,
0:28:57 > 0:29:02and that's fine, but it excludes a lot.
0:29:02 > 0:29:07We think we're understanding, but what we're doing is describing mechanisms
0:29:07 > 0:29:10so that we can usefully intervene in them if we need to do so.
0:29:10 > 0:29:13- Yes. Medicine. - In that sense, they're like maps.
0:29:13 > 0:29:15When you're driving, you want a map.
0:29:15 > 0:29:18You want to know where you're going and how you're going to do it.
0:29:18 > 0:29:21But you wouldn't be so foolish as to mistake that map
0:29:21 > 0:29:24for a full description of the world.
0:29:24 > 0:29:27It's only telling you the things it is there to tell you about.
0:29:27 > 0:29:31The problem with the mechanical model is it's just telling you something very important,
0:29:31 > 0:29:33very useful, very helpful.
0:29:33 > 0:29:37So it's been a great advance for us that we can see these things,
0:29:37 > 0:29:41but the mistake is to think it tells us what we are.
0:29:43 > 0:29:47I think seeing the heart as just a mechanical pump
0:29:47 > 0:29:49has encouraged us to view our bodies as machines
0:29:49 > 0:29:53ruled over by our heads.
0:29:54 > 0:29:58And this has led us to accept that emotions and feelings,
0:29:58 > 0:30:03these things that were historically connected to the heart,
0:30:03 > 0:30:05are somehow less important.
0:30:07 > 0:30:10But recently, I began to question this.
0:30:12 > 0:30:15If I'm being honest about it...
0:30:18 > 0:30:22I've spent a lifetime seeing myself as a rational person,
0:30:22 > 0:30:26essentially summed up by the rational mind,
0:30:26 > 0:30:29living in a rational world, making rational decisions,
0:30:29 > 0:30:32and I have emotions and that's fine, like everybody else.
0:30:32 > 0:30:34Then something...
0:30:34 > 0:30:36An emotional storm breaks out in your life.
0:30:39 > 0:30:43You realise there's a whole side to your life,
0:30:43 > 0:30:45a powerful emotional life,
0:30:45 > 0:30:50which I can't think of any longer as just, "I have emotions."
0:30:50 > 0:30:55I think emotions are, they're like the tide you bob about on
0:30:55 > 0:30:59and if a storm breaks out, God help you.
0:30:59 > 0:31:02But there's no point in denying that side of you.
0:31:04 > 0:31:07I think we're not so much
0:31:07 > 0:31:10rational creatures who happen to have emotions
0:31:10 > 0:31:13but emotional creatures who have thoughts.
0:31:13 > 0:31:16And our hearts remind us of this.
0:31:16 > 0:31:22I've come to believe that seeing the heart as just a pump
0:31:22 > 0:31:24does not just distort how we view ourselves,
0:31:24 > 0:31:27but may also be fundamentally wrong.
0:31:39 > 0:31:43Modern science is now beginning to understand the heart
0:31:43 > 0:31:46in a way that is much more nuanced and complex.
0:31:48 > 0:31:53Some scientists are beginning to return emotion back to the heart,
0:31:53 > 0:31:58exploring how what we think and feel can profoundly affect the heart,
0:31:58 > 0:32:02even, in extreme cases, causing it to fail altogether.
0:32:06 > 0:32:07Professor Peter Taggart
0:32:07 > 0:32:10is a cardiologist at the Heart Hospital in London.
0:32:12 > 0:32:15If you take the English language, for example,
0:32:15 > 0:32:19there are expressions like died of fright, worried to death,
0:32:19 > 0:32:22but everybody believes that emotion affects the heart
0:32:22 > 0:32:25but scientifically, there's very little evidence
0:32:25 > 0:32:27and very little credibility for this,
0:32:27 > 0:32:30so we're trying to actually bridge that gap
0:32:30 > 0:32:32and provide hard scientific facts
0:32:32 > 0:32:36about the way that it does affect the heart.
0:32:36 > 0:32:37So specifically, what is it
0:32:37 > 0:32:41that you are actually looking for in your experiments?
0:32:41 > 0:32:44Well, the ultimate goal, of course, is to look at the way
0:32:44 > 0:32:48that emotion may contribute to sudden death, sudden heart deaths.
0:32:48 > 0:32:51There are a lot of anecdotal examples, as you know,
0:32:51 > 0:32:54of people dying in the course of an argument
0:32:54 > 0:32:58or after a bereavement or some bad stress.
0:32:58 > 0:33:05There's several studies showing that heart deaths go up dramatically
0:33:05 > 0:33:08- after natural disasters such as earthquakes...- Really?
0:33:08 > 0:33:09Wars, and things like that.
0:33:09 > 0:33:13- Not dying from the actual event, but afterwards?- Just afterwards.
0:33:13 > 0:33:15But we don't know how, in fact, this happens.
0:33:15 > 0:33:21And our work, really, is to try and actually understand the mechanisms.
0:33:21 > 0:33:27How does emotion affect the heart itself to create these problems?
0:33:27 > 0:33:29OK, breathe normally.
0:33:29 > 0:33:32OK, I think we could probably take the tube out.
0:33:34 > 0:33:38- Are you happy, Peter? - Yes indeed.- OK.
0:33:38 > 0:33:39Can we take the tube away, please?
0:33:39 > 0:33:42Professor Taggart has invited me to St Thomas's Hospital
0:33:42 > 0:33:47to see an experiment exploring the surprisingly complex way
0:33:47 > 0:33:50in which emotion can effect the heart.
0:33:50 > 0:33:52A little bit more pushing.
0:33:53 > 0:33:56This patient has a problem with his heart
0:33:56 > 0:33:59and has come to hospital for treatment.
0:33:59 > 0:34:02A series of catheters are being fed through his blood vessels
0:34:02 > 0:34:05into the heart's inner chambers.
0:34:05 > 0:34:08Just going to put a little more local anaesthetic in on this side.
0:34:08 > 0:34:12The catheters contain 20 individual electrodes
0:34:12 > 0:34:16which will allow the electrical activity inside his heart
0:34:16 > 0:34:19to be recorded in minute detail.
0:34:20 > 0:34:23Now, just going to leave that to work for a little while as well.
0:34:23 > 0:34:27Before his treatment begins, whilst wired up,
0:34:27 > 0:34:32he has agreed to watch two short videos for Peter's experiment.
0:34:32 > 0:34:36I'll start this dot moving around on the screen and if you can just...
0:34:36 > 0:34:39This first video is designed to relax the patient,
0:34:39 > 0:34:42and give a measurement of his heart without emotion.
0:34:43 > 0:34:47And your monitoring the heart through that equipment?
0:34:47 > 0:34:51The recordings will give the electrical behaviour
0:34:51 > 0:34:56on the right side of the heart and the left side of the heart
0:34:56 > 0:34:59along with blood pressure and the motion of the breathing.
0:34:59 > 0:35:01So you have a very clear picture
0:35:01 > 0:35:05- of how his heart is reacting to watching that film?- Yes, in detail.
0:35:07 > 0:35:10The patient is then shown a dramatic scene
0:35:10 > 0:35:13from the Hollywood movie Vertical Limit,
0:35:13 > 0:35:14which Peter has specially selected
0:35:14 > 0:35:18to produce a strong emotional response.
0:35:18 > 0:35:20And this is a little scene where
0:35:20 > 0:35:23there's a group of climbers on a cliff,
0:35:23 > 0:35:25and the rope is pulling out of the cliff
0:35:25 > 0:35:27and the only way they can save themselves is by
0:35:27 > 0:35:31reducing the weight on the rope. That means cutting the bottom person loose
0:35:31 > 0:35:35and the bottom person is the father of the family which are on the rope.
0:35:35 > 0:35:37- No.- There's too much weight. One cam will never hold us.
0:35:37 > 0:35:39You have to cut me loose.
0:35:39 > 0:35:43Everybody knows that when you're excited or stressed,
0:35:43 > 0:35:45your heart beats faster.
0:35:45 > 0:35:49But Peter is interested in something far more intricate
0:35:49 > 0:35:52than what happens to just the heart rate.
0:35:52 > 0:35:55His measurements are designed to detect how
0:35:55 > 0:35:59the actual beat of the heart itself can change in response to emotion.
0:35:59 > 0:36:03If you don't do this, I'll pull everybody down and everybody'll die!
0:36:03 > 0:36:04- It'll hold!- Shut up, Annie!
0:36:05 > 0:36:09The heartbeat is controlled by electrical waves
0:36:09 > 0:36:10which travel across the heart,
0:36:10 > 0:36:13causing the muscle to contract and relax.
0:36:14 > 0:36:16Is it working, your experiment?
0:36:16 > 0:36:19It's getting very exciting. What we're finding is that
0:36:19 > 0:36:23when the person watches something that is boring and bland,
0:36:23 > 0:36:26- nothing happens to the measurements.- Right.
0:36:26 > 0:36:28When they watch something exciting
0:36:28 > 0:36:31or in this case, a really dramatic scene...
0:36:31 > 0:36:35- No!- It's one dead or three, Peter! Understand?- Don't make him do this!
0:36:35 > 0:36:37..then there's a measurable change
0:36:37 > 0:36:41in the way that the electrical waves circulate through the heart.
0:36:41 > 0:36:46Peter believes that in people with more vulnerable, damaged hearts,
0:36:46 > 0:36:49this effect could be enough to trigger the heart's rhythm
0:36:49 > 0:36:51to break down entirely.
0:36:51 > 0:36:54- We're going to die!- No! - Annie, we're all going to die!
0:36:54 > 0:36:57Just cut it, Peter! Just cut it!
0:36:58 > 0:37:00It does sound like you're...
0:37:00 > 0:37:05you're re-establishing the connection of emotions to the heart.
0:37:05 > 0:37:08Well, I think everybody's sort of concept of the heart
0:37:08 > 0:37:11is that it's a pump
0:37:11 > 0:37:16and when you, when you, for example, have death,
0:37:16 > 0:37:20that the heart stops and that it may cease to function properly
0:37:20 > 0:37:23because instead of beating nice and synchronously,
0:37:23 > 0:37:28the rhythm changes and the activation waves go all irregular
0:37:28 > 0:37:35and it becomes discoordinate and the function goes.
0:37:35 > 0:37:38And you're saying it can be emotions that can trigger that.
0:37:38 > 0:37:40And this is the sort of thing that can do that
0:37:40 > 0:37:42in an already-compromised heart.
0:37:42 > 0:37:47- I would stress that this only happens in very, very poorly hearts.- Right.
0:37:47 > 0:37:51But...it sounds, and forgive me if I'm wrong,
0:37:51 > 0:37:53but it sounds as if you're tiptoeing back towards
0:37:53 > 0:37:56people who talk about, "He died of a broken heart."
0:37:56 > 0:37:59- Exactly.- Really?- Yes.
0:37:59 > 0:38:02Well, I think there's a whole mass of anecdotal evidence
0:38:02 > 0:38:04but anecdotal evidence is anecdotal
0:38:04 > 0:38:06and it doesn't have scientific credibility.
0:38:06 > 0:38:08What we're trying to do now
0:38:08 > 0:38:11is to give, I suppose, scientific credibility
0:38:11 > 0:38:15to what people have known for thousands of years.
0:38:15 > 0:38:16Yes, yes.
0:38:16 > 0:38:20- I'm glad you're doing it! - Well, not before time.
0:38:32 > 0:38:34I've always felt
0:38:34 > 0:38:37that poetry doesn't work unless it has one foot in reality.
0:38:39 > 0:38:42And now science is suggesting
0:38:42 > 0:38:45that the poetry of the heart might hold some truth.
0:38:45 > 0:38:49It does seem to me we've already come quite a long way from Descartes
0:38:49 > 0:38:53where the heart suddenly was, there was no emotion at all,
0:38:53 > 0:38:56it was completely stripped of any emotion. It seems to me that
0:38:56 > 0:39:00science is beginning to put some of that emotion back.
0:39:00 > 0:39:03It's not quite, you know, the seat of the soul...
0:39:05 > 0:39:07..but it's not an unemotional thing either.
0:39:10 > 0:39:14But science is not just returning emotion back to the heart.
0:39:14 > 0:39:17In other fundamental ways,
0:39:17 > 0:39:22it is rethinking the whole relation between heart and mind,
0:39:22 > 0:39:24emotion and reason.
0:39:27 > 0:39:31'I've come to Oxford, to meet Professor David Paterson,
0:39:31 > 0:39:35'who is at the forefront of this new revolution.'
0:39:35 > 0:39:37- So welcome to Merton College. - Thank you very much.
0:39:43 > 0:39:46My research really straddles
0:39:46 > 0:39:48between these two organs, the brain and the heart,
0:39:48 > 0:39:52because historically, they've always been viewed as islands to themselves.
0:39:52 > 0:39:54Fantastic. I want to hear about this.
0:39:59 > 0:40:01Professor Paterson's research
0:40:01 > 0:40:03is helping challenge the traditional view
0:40:03 > 0:40:07of how the heart and brain work together.
0:40:07 > 0:40:10The brain is made up of billions of neurons
0:40:10 > 0:40:12and is able to influence the heart rate
0:40:12 > 0:40:15by sending messages down the different nerve fibres,
0:40:15 > 0:40:17the wiring of the human body.
0:40:18 > 0:40:21When the heart receives signals from the brain
0:40:21 > 0:40:24through the sympathetic nerves, it pumps faster.
0:40:26 > 0:40:30And when it receives signals through the parasympathetic nerves,
0:40:30 > 0:40:31it slows down.
0:40:36 > 0:40:38On its own, this appears to fit
0:40:38 > 0:40:42with the picture of the heart enslaved to the brain.
0:40:42 > 0:40:46But the true relationship between the two organs is far more nuanced.
0:40:46 > 0:40:49If you look at a heart...
0:40:49 > 0:40:50You happen to have one with you.
0:40:50 > 0:40:52And I happen to have a heart in my pocket,
0:40:52 > 0:40:55which all good physiologists carry around with them,
0:40:55 > 0:40:59but the traditional anatomical view of the nervous system and the heart
0:40:59 > 0:41:03is that you have these major two nerves coming down from the brain.
0:41:03 > 0:41:07- Which is just telling the heart what to do.- Speed up, slow down.- Yeah.
0:41:07 > 0:41:09But in the heart itself,
0:41:09 > 0:41:15you have around 10,000 or so very specialised neurons that sit there,
0:41:15 > 0:41:18and these predominantly lie around the right atrial surfaces...
0:41:18 > 0:41:21- Not just nerve cells?- Not just nerve cells.- You're using neuron advisedly.
0:41:21 > 0:41:23..that form networks.
0:41:23 > 0:41:26- OK.- And that begs the question...
0:41:26 > 0:41:30- Begging many questions! - Well, what is their role?
0:41:30 > 0:41:33Why are they there? Why has nature put them there?
0:41:33 > 0:41:37Yes. Why are you the first person to tell me this?
0:41:37 > 0:41:40- Well, it's not established in textbooks.- But why not?
0:41:40 > 0:41:43Well, I think the textbooks need to be rewritten
0:41:43 > 0:41:45and they are being rewritten.
0:41:47 > 0:41:50It's astonishing to think that neurons,
0:41:50 > 0:41:54the very cells that make up the brain in our heads
0:41:54 > 0:41:56and give us the ability to think,
0:41:56 > 0:41:59are also present within the heart.
0:42:00 > 0:42:02And there are so many of them
0:42:02 > 0:42:06that these neurons have been called by those who study them
0:42:06 > 0:42:08the heart's little brain.
0:42:08 > 0:42:10Much about the heart's neurons is still unknown,
0:42:10 > 0:42:12but one thing is clear -
0:42:12 > 0:42:16that the brain in our heads doesn't simply control the heart,
0:42:16 > 0:42:19but works in partnership with it.
0:42:19 > 0:42:21Right.
0:42:21 > 0:42:23This is a little bit different from college.
0:42:25 > 0:42:29What you're looking at is a section of tissue taken from a rat's heart.
0:42:29 > 0:42:33It contains most of the neurons that make up the heart's little brain.
0:42:35 > 0:42:39The tissue is being kept alive by a solution of nutrients
0:42:39 > 0:42:41and the bubbling oxygen
0:42:41 > 0:42:44and if you look closely,
0:42:44 > 0:42:48you can see that the tissue is beating of its own accord.
0:42:48 > 0:42:52So this is a, just a little bit of the right atrial tissue
0:42:52 > 0:42:55and inside, there are these neurons
0:42:55 > 0:43:00and in fact, what we see here is that the tissue is beating by itself.
0:43:00 > 0:43:02So is that, it looks like a heartbeat?
0:43:02 > 0:43:05That's right, it's very similar. It's an actual contraction
0:43:05 > 0:43:11so this is beating at about 180, almost 200 beats per minute.
0:43:11 > 0:43:14Professor Paterson is going to show me
0:43:14 > 0:43:18that by sending an electric signal to the heart's little brain,
0:43:18 > 0:43:22that little brain can then slow down the heart rate.
0:43:22 > 0:43:26This mimics how the brain in our heads asks the heart to slow down,
0:43:26 > 0:43:31a process that relies on the neurons in the heart.
0:43:31 > 0:43:35We've got a very small electrode sitting over by these neurons,
0:43:35 > 0:43:36so we're going to excite them.
0:43:38 > 0:43:39I get to press the button?
0:43:39 > 0:43:43- And then look at the trace. - I'm quite nervous about it.
0:43:43 > 0:43:46- Here, see?- Oh, my God!- See that?
0:43:46 > 0:43:48- See, it's slowed down? - That's dramatic!
0:43:48 > 0:43:51So what you're doing is, you're activating the neurons.
0:43:51 > 0:43:53So I sent it a little mental signal?
0:43:53 > 0:43:56- Yeah, a mental signal. - It's going further down.
0:43:56 > 0:43:58Yeah, because you're maintaining the stimulation.
0:43:58 > 0:44:00- I'm going to switch it off. - So turn it off.
0:44:00 > 0:44:02And then...
0:44:02 > 0:44:05The parasympathetic nervous system is now back off.
0:44:05 > 0:44:08- And back it's coming. - And up it comes again. Isn't that...
0:44:08 > 0:44:12- It's fast, too. - It's very quick.- Look at that.
0:44:12 > 0:44:14In fact, it happens within about a beat.
0:44:15 > 0:44:19What we've done is completely taken the brain out of the picture.
0:44:19 > 0:44:23- We've just electrically excited those neurons.- Yes.
0:44:23 > 0:44:26- So right down at the tissues... - The neurons in the heart.
0:44:26 > 0:44:29- And now they're taking over, they're doing it.- They're taking over
0:44:29 > 0:44:33and they're releasing the chemical messages to then slow the heart down.
0:44:33 > 0:44:35So in a way, that's demonstrating
0:44:35 > 0:44:41how much of that neural control is in the heart.
0:44:41 > 0:44:43Is in the heart itself, because...
0:44:43 > 0:44:46- We evidently don't have a brain, we have a small...- Stimulator.
0:44:46 > 0:44:50Small grotty-looking pile of simple electronics. That's not a brain.
0:44:50 > 0:44:53- That's right.- So the decision - using the word slightly metaphorically -
0:44:53 > 0:44:56- is happening in there.- It's happening in there, that's right,
0:44:56 > 0:44:59- completely devoid of the essential nervous system.- Wow.
0:44:59 > 0:45:01- That's rather impressive. And it looks great.- Yeah.
0:45:01 > 0:45:07This shows the extent to which it is these neurons in the heart
0:45:07 > 0:45:10that control what the heart does, not the brain.
0:45:12 > 0:45:16Professor Paterson's work is revealing just how complex
0:45:16 > 0:45:18the little brain in the heart really is.
0:45:20 > 0:45:23See if we can see some of the heart cells beating.
0:45:23 > 0:45:26- There!- I saw them pulse there.
0:45:26 > 0:45:27OK.
0:45:28 > 0:45:32These are the neurons that make up the heart's little brain.
0:45:32 > 0:45:37They live side-by-side with the cardiac muscle cells in the heart.
0:45:39 > 0:45:43They really are a unit, then, aren't they? I mean, it's not just,
0:45:43 > 0:45:45"Here's the heart doing everything the heart does
0:45:45 > 0:45:48"and then we've got some neurons just watching what's going on."
0:45:48 > 0:45:52- There's an active partnership here. - No question about that.
0:45:52 > 0:45:57We need to understand this. It's very poorly understood,
0:45:57 > 0:46:00the detailed neurochemistry, the detailed electrophysiology.
0:46:00 > 0:46:04We're only really starting to scratch the surface
0:46:04 > 0:46:07of this network in the heart.
0:46:07 > 0:46:12Gosh, we are a long way from just playing with the plumbing of a pump.
0:46:12 > 0:46:14Much more complex than that.
0:46:21 > 0:46:28I suppose I feel, I feel optimistic, having talked to Professor Paterson.
0:46:28 > 0:46:31Because I do have to admit
0:46:31 > 0:46:36that after the first day, I felt, I felt quite concerned.
0:46:36 > 0:46:39We got such a telling-off that I thought,
0:46:39 > 0:46:43"Maybe this film really has gone off in all the wrong direction.
0:46:43 > 0:46:47"Maybe what we're trying to say is just silly."
0:46:47 > 0:46:49But having talked to Professor Paterson,
0:46:49 > 0:46:54I feel that there really is something important,
0:46:54 > 0:46:56something scientifically true...
0:46:58 > 0:47:01..but also something important that we are trying to say
0:47:01 > 0:47:03and I feel good about that.
0:47:18 > 0:47:22Modern science is now painting a picture of the heart
0:47:22 > 0:47:26that I believe is much closer to how we really are.
0:47:26 > 0:47:29The heart is a pump
0:47:29 > 0:47:32that does respond when the brain asks it to,
0:47:32 > 0:47:35but it is not enslaved to the brain.
0:47:37 > 0:47:40Its relationship with the brain is more like a marriage,
0:47:40 > 0:47:46living in partnership with each dependent upon the other.
0:47:46 > 0:47:49But most importantly,
0:47:49 > 0:47:52it seems to me science is now restoring to the heart
0:47:52 > 0:47:57something of what rightfully belongs to it - our emotions.
0:48:02 > 0:48:05Because it is not just thoughts that govern our lives.
0:48:10 > 0:48:13Well, a couple of years ago, my wife became...
0:48:16 > 0:48:19..profoundly depressed, clinically depressed.
0:48:19 > 0:48:21And...
0:48:24 > 0:48:25The person I fell in love with,
0:48:25 > 0:48:28the person who I've lived with my adult life, is...
0:48:30 > 0:48:32..is gone.
0:48:33 > 0:48:35And it...
0:48:38 > 0:48:40And it's...
0:48:42 > 0:48:46It's a very painful thing, not just rationally painful...
0:48:50 > 0:48:52I...
0:48:52 > 0:48:58I never knew what that phrase, "my heart ached" or "my heart broke,"
0:48:58 > 0:49:00it was just poetry for me, but it isn't any more.
0:49:08 > 0:49:14I just suddenly was confronted by a question I'd never thought about,
0:49:14 > 0:49:17about this relationship between...
0:49:21 > 0:49:23The life of my heart,
0:49:23 > 0:49:26the emotional life, the emotional centre of it,
0:49:26 > 0:49:28which when it was fine, I never thought about,
0:49:28 > 0:49:30I just took it for granted.
0:49:32 > 0:49:34But something went wrong with my...
0:49:36 > 0:49:38..wife's mind.
0:49:43 > 0:49:44And, uh...
0:49:45 > 0:49:47It's hurting my heart.
0:49:49 > 0:49:54Can you make sense of the most emotionally difficult things in your life
0:49:54 > 0:49:57simply by having a rational think about them?
0:49:59 > 0:50:01This is what I've tried for the last two years,
0:50:01 > 0:50:04and I can tell you, it doesn't work.
0:50:07 > 0:50:14When, you know, this illness took Sarah away from me,
0:50:14 > 0:50:18I sort of felt, well, it's so easy for the rational mind to say,
0:50:18 > 0:50:21"Look, it's a rational world and we have rational thoughts
0:50:21 > 0:50:25"and you keep those silly emotions at bay because they get in the way,"
0:50:25 > 0:50:27but I don't have a clear...
0:50:27 > 0:50:29I can't sum it up in two or three rational sentences.
0:50:29 > 0:50:31But what makes you think you have to sum it up
0:50:31 > 0:50:33in two or three rational sentences?
0:50:33 > 0:50:35I don't know. That's a good question.
0:50:35 > 0:50:39I don't know, I thought I should be able to, that there would be a...
0:50:40 > 0:50:41Well, you're talking about
0:50:41 > 0:50:45the most mysterious and complicated things that we experience
0:50:45 > 0:50:51and...it's unkind to yourself
0:50:51 > 0:50:54to think you would be able to sum that up in two or three sentences,
0:50:54 > 0:50:56and indeed, it's not likely
0:50:56 > 0:51:00that we would ever be able to sum up such things in that way.
0:51:04 > 0:51:08I'm not going to find the way forward through an emotional storm
0:51:08 > 0:51:12just by consulting the rational part of my mind.
0:51:13 > 0:51:16I feel there's a whole other side to me,
0:51:16 > 0:51:18which unless I give it a voice,
0:51:18 > 0:51:20unless I listen to what it's telling me,
0:51:20 > 0:51:22I'm not going to make it through.
0:51:23 > 0:51:25And that's my heart.
0:51:25 > 0:51:30But what does it mean to follow your heart?
0:51:47 > 0:51:50I would like to think that the heart's influence
0:51:50 > 0:51:54is as it has always been imagined by the poets.
0:51:54 > 0:51:58That is makes us kinder, more compassionate people.
0:52:01 > 0:52:04The final thing I want to explore about the heart
0:52:04 > 0:52:06is how it can affect the mind.
0:52:14 > 0:52:18In this experiment, images of frightened and calm faces
0:52:18 > 0:52:21are being shown to me for split seconds.
0:52:23 > 0:52:25Some in time with my heartbeat...
0:52:26 > 0:52:29..and others out of time.
0:52:29 > 0:52:33And I'm being asked to judge the intensity of the face.
0:52:33 > 0:52:36This research is being carried out by Professor Hugo Critchley
0:52:36 > 0:52:41and Dr Sarah Garfinkel at Brighton and Sussex Medical School.
0:52:41 > 0:52:44- And how was that?- 'Stressful.'
0:52:44 > 0:52:45Just take this off...
0:52:45 > 0:52:47'No, it was quite weirdly intense.'
0:52:47 > 0:52:49The second one started out fine...
0:52:49 > 0:52:53- Yeah.- And then got more worrisome.
0:52:53 > 0:52:54OK, so we can come through here.
0:52:54 > 0:52:56'What Hugo and Sarah are interested in'
0:52:56 > 0:53:00is whether my brain experiences the faces differently
0:53:00 > 0:53:02if they are shown to me in time with my heart.
0:53:04 > 0:53:06This is your intensity ratings here.
0:53:06 > 0:53:11- Right.- And if fear faces were out of sync with your heart,
0:53:11 > 0:53:14then you rated them as less intense.
0:53:14 > 0:53:16- Right.- If they were in sync with your heart,
0:53:16 > 0:53:18then you rated them as more intense
0:53:18 > 0:53:20and if you look at the other categories,
0:53:20 > 0:53:22there was no difference of heartbeat.
0:53:22 > 0:53:25- Neutral faces, it made no difference. - It's the same.- Exactly.
0:53:25 > 0:53:32So the only time the heart was influencing your emotion ratings
0:53:32 > 0:53:35- was when it was an explicit fear face.- Right.
0:53:36 > 0:53:38The results show
0:53:38 > 0:53:42that when frightened faces were shown in time with my heartbeat,
0:53:42 > 0:53:45I perceived them to be more frightened.
0:53:45 > 0:53:49In other words, how my mind processed the fear faces
0:53:49 > 0:53:51was affected by my heart.
0:53:54 > 0:53:57- So, if we look at it... - 'From the brain scans,
0:53:57 > 0:54:02'Hugo and Sarah are able to pinpoint the exact region of the brain
0:54:02 > 0:54:03'that is affected by the heart.'
0:54:05 > 0:54:09When your brain is processing fear in time with your heart beating,
0:54:09 > 0:54:11we get this great mass of activity
0:54:11 > 0:54:14in a region of the brain called the amygdala, which is known...
0:54:14 > 0:54:18- Ah, yes.- ..to be the threat processing region of the brain,
0:54:18 > 0:54:21just showing that the amygdala processes fear
0:54:21 > 0:54:24in conjunction with the heart's signalling when it's beating.
0:54:24 > 0:54:27Does that light up more when it's in sync with the heart
0:54:27 > 0:54:29- than if it's not?- Absolutely. - Really?- Yeah.
0:54:29 > 0:54:34'But the experiment had an unexpected effect on me.'
0:54:34 > 0:54:37Although I was being shown frightened faces,
0:54:37 > 0:54:40it was not fear that I felt, but concern.
0:54:40 > 0:54:44The faces were reminding me of someone I care about.
0:54:45 > 0:54:50It was rather an intense experience, because I was looking at those faces
0:54:50 > 0:54:54and feeling worried about those people,
0:54:54 > 0:54:57not those people, I was looking at those faces and it was reminding me
0:54:57 > 0:55:03of someone I care about and thinking, thinking about their...
0:55:04 > 0:55:06..their pain or their sadness,
0:55:06 > 0:55:09and that was what made it very intense for me,
0:55:09 > 0:55:12but is that really what was going on?
0:55:12 > 0:55:17Certainly, the way we interpret other people's emotions
0:55:17 > 0:55:19is very much influenced
0:55:19 > 0:55:23by our capacity to embody their emotional state.
0:55:23 > 0:55:29If I see someone...in pain, something bad happens to them,
0:55:29 > 0:55:34you're saying that my heart helps me to create some...
0:55:34 > 0:55:37- Understanding of them. - Part of that feeling.
0:55:37 > 0:55:39From an emotional level, yeah, absolutely.
0:55:39 > 0:55:42So certainly, this emotional system
0:55:42 > 0:55:46is very much tuned into emotions like compassion for other people,
0:55:46 > 0:55:48empathising with people's emotional states,
0:55:48 > 0:55:53as well as producing the kind of shared joy and positive emotions
0:55:53 > 0:55:59- that, you know, that bond us socially.- That's, that's fantastic.
0:55:59 > 0:56:05So that, you know, that phrase, "I feel for you" - you do.
0:56:05 > 0:56:08You're telling me my heart is able to make that true, that statement.
0:56:08 > 0:56:11The heart is certainly a big component.
0:56:11 > 0:56:12I consider the heart to be
0:56:12 > 0:56:15one of the main channels of that kind of information.
0:56:18 > 0:56:22It seems that the heart beats not just with our own emotions,
0:56:22 > 0:56:24but also with other people's.
0:56:26 > 0:56:29It is our hearts, working in tandem with our brains,
0:56:29 > 0:56:32that allow us to feel for others.
0:56:33 > 0:56:39And painful though it might be at times to experience that compassion,
0:56:39 > 0:56:42it is ultimately what makes us human.
0:56:44 > 0:56:50For me, compassion is the heart's gift to the rational mind.
0:56:50 > 0:56:54The things I hoped would be true about being human,
0:56:54 > 0:56:57I'm reassured that they are true.
0:56:59 > 0:57:03And the things I hoped would be
0:57:03 > 0:57:07how we work and the kind of creatures we are, they really are,
0:57:07 > 0:57:11you can experimentally see that IS how we work
0:57:11 > 0:57:15and it DOES underpin the thing about us
0:57:15 > 0:57:18which I personally feel is what makes us a worthwhile species,
0:57:18 > 0:57:21that we can feel compassion for other people.
0:57:21 > 0:57:26I'm not really hugely impressed that we can...build faster jets,
0:57:26 > 0:57:29but that we are made in such a way
0:57:29 > 0:57:33that we can feel someone else's pain and feel compassion for them...
0:57:34 > 0:57:37I think that's fantastic.
0:57:38 > 0:57:43In the end, this battle between the head and the heart
0:57:43 > 0:57:48to decide what's the best part of us leaves no triumphant victor.
0:57:48 > 0:57:51In reality, we need both.
0:57:52 > 0:57:55The heart may be more than just a pump.
0:57:55 > 0:57:58It may help us to care for one another,
0:57:58 > 0:58:00but it is stuck in the present.
0:58:04 > 0:58:07It is only the brain that can imagine a different world
0:58:07 > 0:58:09and invent it,
0:58:09 > 0:58:12but if we want that world to be a better world,
0:58:12 > 0:58:15then surely we also have to listen to the heart.
0:58:51 > 0:58:54Subtitles by Red Bee Media Ltd