0:00:04 > 0:00:06What does a brain need to be healthy?
0:00:08 > 0:00:11Well, it needs nutrients from the food you eat,
0:00:11 > 0:00:14it needs oxygen from your blood, plenty of water.
0:00:14 > 0:00:18But there's something else, something equally as important.
0:00:18 > 0:00:20It needs other people.
0:00:20 > 0:00:25CHEERING
0:00:31 > 0:00:34Human beings are extremely social creatures.
0:00:36 > 0:00:39We come together, we team up,
0:00:39 > 0:00:43we share moments of intense joy and disappointment.
0:00:46 > 0:00:49We don't just seek out other people to have a good time.
0:00:49 > 0:00:53Your brain function depends on the social web that you're in.
0:00:53 > 0:00:58Your neurons require other people's neurons to thrive and survive.
0:00:59 > 0:01:03I want to show you how our brains are fundamentally wired
0:01:03 > 0:01:04to work together...
0:01:07 > 0:01:10..how this social network that envelops us
0:01:10 > 0:01:13from birth is vital for our survival.
0:01:17 > 0:01:19Yeah? OK!
0:01:19 > 0:01:22Understanding how brains deal with each other allows us
0:01:22 > 0:01:28to understand what bonds our species, driving us to help
0:01:28 > 0:01:32one another and what makes us hate...
0:01:33 > 0:01:36..what allows acts of human violence.
0:01:37 > 0:01:41It helps us to make sense of our past
0:01:41 > 0:01:43and holds the key to our future.
0:01:56 > 0:02:02There are seven billion people living today - seven billion brains
0:02:02 > 0:02:06moving, choosing, acting,
0:02:06 > 0:02:10believing and connecting with other brains.
0:02:12 > 0:02:16Brains are traditionally studied in isolation but, in fact,
0:02:16 > 0:02:20much of the circuitry of the brain has to do with other brains.
0:02:20 > 0:02:22We're fundamentally social creatures
0:02:22 > 0:02:26and our society is a complex web of interaction.
0:02:26 > 0:02:31On any normal day, we intersect with an enormous number of people.
0:02:33 > 0:02:36'Our lives are built on these intersections,
0:02:36 > 0:02:42'not just between us and our family and friends and work colleagues,
0:02:42 > 0:02:45'but also between them and the people they meet.'
0:02:51 > 0:02:54'Even the most basic encounter...'
0:02:54 > 0:02:56like getting a cup of coffee...
0:02:56 > 0:02:59'..relies on trust with a stranger.'
0:02:59 > 0:03:01- Could I get a latte, please? - Definitely.- Thanks.
0:03:04 > 0:03:10Everywhere we look, we see complex social interactions, relationships
0:03:10 > 0:03:16forming and breaking, bonds of love and support, social networking.
0:03:18 > 0:03:22'We clump into large groups to share our knowledge.'
0:03:22 > 0:03:25You've got all these random spots in your brain that get
0:03:25 > 0:03:27wired up into an associative neural network.
0:03:27 > 0:03:32'We work to impress each other and we swap ideas.'
0:03:32 > 0:03:34I'll stick around for any questions that anyone has. Thank you.
0:03:34 > 0:03:37CLAPPING
0:03:38 > 0:03:41'Most research looks at one brain at a time,
0:03:41 > 0:03:45'but that misses the fact that a great deal of our brain activity
0:03:45 > 0:03:49'is dedicated to communicating with each other,
0:03:49 > 0:03:50'interpreting each other.'
0:03:51 > 0:03:55'Our social drive is deeply rooted in our neural circuitry.'
0:04:00 > 0:04:02Take a look at this film from the 1940s.
0:04:02 > 0:04:04What do you see happening here?
0:04:05 > 0:04:10Is this just a simple animation of some shapes or something more?
0:04:10 > 0:04:14Do you see a chase, a fight, a love story?
0:04:16 > 0:04:20The big one seems to be pushing the little one around.
0:04:20 > 0:04:25It seems like the two triangles are in a little bit of a squabble.
0:04:25 > 0:04:26There are relationships here
0:04:26 > 0:04:29in terms of one is more dominant than the other.
0:04:31 > 0:04:34Back in the 1940s, psychologists Fritz Heider
0:04:34 > 0:04:39and Marianne Simmel created this film as part of an experiment.
0:04:39 > 0:04:42- The ball doesn't seem to want to be in there.- It's freaking out.
0:04:42 > 0:04:45It's scared. It looks like a trap to me.
0:04:46 > 0:04:49It looks like the smaller triangle is being shut out and, like,
0:04:49 > 0:04:52trying to peer in.
0:04:52 > 0:04:56- They are paired in a way that seems friendly.- Yeah.
0:04:56 > 0:04:58- This is really fun.- It's fun, right?
0:04:59 > 0:05:02'What Heider and Simmel found, as I did,
0:05:02 > 0:05:07'is how easy it is to look at moving shapes and to see meaning
0:05:07 > 0:05:12'and motives and emotion, all in the form of a social narrative.'
0:05:14 > 0:05:16I kind of get the sense that they're cats and dogs.
0:05:16 > 0:05:18It seemed like the big one might have been,
0:05:18 > 0:05:20like, his dad or something.
0:05:20 > 0:05:22Just call it more of, like, a mating ritual -
0:05:22 > 0:05:25two competitors going for one possible mate.
0:05:28 > 0:05:31These are just shapes on a screen but we can't help
0:05:31 > 0:05:34but tell stories about them. Why?
0:05:34 > 0:05:37It's because our brains are so primed for social interaction
0:05:37 > 0:05:41that we look for intention in relationships all around us.
0:05:43 > 0:05:45One way we navigate the social world
0:05:45 > 0:05:49is by judging other people's intentions.
0:05:49 > 0:05:52Is she is trying to be helpful?
0:05:54 > 0:05:56Are we a trustworthy team?
0:05:57 > 0:06:00Our brains are good at making these sorts of judgements
0:06:00 > 0:06:03and we do it constantly
0:06:03 > 0:06:07but do we learn this skill from life experience or are we born with it?
0:06:10 > 0:06:13To figure out which one it is, I've invited over some people who
0:06:13 > 0:06:16don't have much experience with the world.
0:06:16 > 0:06:18SHE CRIES
0:06:18 > 0:06:20I've invited them to a puppet show.
0:06:22 > 0:06:26These babies are all under 12 months old.
0:06:26 > 0:06:30They're just beginning to explore the world around them.
0:06:30 > 0:06:33You could say they're all a little short on life experience.
0:06:35 > 0:06:37We decided to run a simple experiment
0:06:37 > 0:06:39developed at Yale University.
0:06:44 > 0:06:46Here's a duck struggling to open a box.
0:06:51 > 0:06:53One bear helps the duck.
0:06:59 > 0:07:01The other is mean to the duck.
0:07:05 > 0:07:08OK, Booey. Here you go. There are two puppets.
0:07:08 > 0:07:12'When the show's over, I let the babies choose a bear to play with.'
0:07:15 > 0:07:17Yeah, OK. Is that the one you like? All right.
0:07:17 > 0:07:21'Almost every one of them chooses the bear that's been kind.'
0:07:23 > 0:07:25'These babies can't walk or talk
0:07:25 > 0:07:30'and yet they already have the tools to make judgements about others.'
0:07:32 > 0:07:33Yeah? OK!
0:07:35 > 0:07:37It's often assumed that trust is something that we
0:07:37 > 0:07:40learn from our experience in the world, but these experiments
0:07:40 > 0:07:44demonstrate that, even as babies, we come equipped with
0:07:44 > 0:07:47social antennae for feeling our way through the world.
0:07:47 > 0:07:51The brain comes with inborn instincts for figuring out
0:07:51 > 0:07:53who's trustworthy and who's not.
0:07:53 > 0:07:54BABY GURGLES
0:07:55 > 0:08:00As we grow, our social challenges become even more subtle
0:08:00 > 0:08:01and complex.
0:08:03 > 0:08:07Understanding others is one of the most demanding operations
0:08:07 > 0:08:08that our brains perform.
0:08:11 > 0:08:16They have to interpret words and, more than that, inflection,
0:08:16 > 0:08:18facial expressions, body language.
0:08:21 > 0:08:22Does she like me?
0:08:24 > 0:08:26Is he interested in what I'm saying?
0:08:28 > 0:08:29Do they want my help?
0:08:31 > 0:08:37Society runs on our ability to read each other's social signals.
0:08:39 > 0:08:44Take that ability away and the world becomes a very strange place.
0:08:52 > 0:08:56Car enthusiast John Robeson has always struggled to read
0:08:56 > 0:08:57other people.
0:08:59 > 0:09:03When I was a little boy, I was bullied and rejected by
0:09:03 > 0:09:07other kids, and that didn't happen with machines, you know.
0:09:07 > 0:09:12I could stand by a tractor in my grandparents' farm
0:09:12 > 0:09:16and I could learn how to adjust it and it wouldn't tease me
0:09:16 > 0:09:18or do anything bad, it wouldn't run away, it would
0:09:18 > 0:09:20always be there and I could count on it.
0:09:20 > 0:09:24And I guess I learned to make friends with
0:09:24 > 0:09:29the machines before I learned how to make friends with other people.
0:09:29 > 0:09:32In time, John's affinity for technology took him
0:09:32 > 0:09:35to places his bullies could only dream of.
0:09:36 > 0:09:40By 21, he was a roadie for the band Kiss.
0:09:40 > 0:09:44This was me, back with Kiss in the '70s.
0:09:44 > 0:09:47I'm older and fatter and stuff. I don't look the same any more.
0:09:50 > 0:09:53Surrounded by legendary rock and roll excess,
0:09:53 > 0:09:57his outlook remained different from other people's.
0:09:57 > 0:10:00People would come up to me all the time and they would say,
0:10:00 > 0:10:03"What's this guy like?" or, "What's that guy like?"
0:10:04 > 0:10:06I would say, "Yeah, their stage set-up,
0:10:06 > 0:10:10"they had Sunn 2000S bass amps," or, "Gene played Sunn Coliseums,
0:10:10 > 0:10:13"and we had seven bass amps chained together,
0:10:13 > 0:10:16"we had 2,200 watts in the bass system for that."
0:10:17 > 0:10:18But I maybe couldn't tell you
0:10:18 > 0:10:21the first thing about the musicians who sang through them.
0:10:24 > 0:10:28Now I realise that shows that I did kind of live in
0:10:28 > 0:10:32a different world all those years - a world of machines and equipment.
0:10:35 > 0:10:41When he was 40, John was diagnosed with Asperger's - a form of autism.
0:10:48 > 0:10:51Many regions of the brain are engaged during
0:10:51 > 0:10:56social interaction, but in autism, that brain activity isn't seen
0:10:56 > 0:11:01as strongly, and that's paralleled by diminished social skills.
0:11:02 > 0:11:08I didn't really understand that there were complex messages
0:11:08 > 0:11:13in faces until I was well into adulthood and learned about autism.
0:11:15 > 0:11:20I knew that people could display signs of crazed anger..
0:11:22 > 0:11:28..but if you asked about more subtle expressions, you know,
0:11:28 > 0:11:31I think you're sweet and I wonder what you're hiding,
0:11:31 > 0:11:35or, I'd really like to do that, or, I wish you'd do this or that, I...
0:11:36 > 0:11:39I had no idea about things like that.
0:11:45 > 0:11:48But then came a transforming moment in John's life.
0:11:49 > 0:11:54In 2008, he was invited to Harvard Medical School to take part
0:11:54 > 0:12:00in an experiment on his brain - overseen by Dr Alvaro Pascual-Leone.
0:12:02 > 0:12:05It was an attempt to try to understand
0:12:05 > 0:12:07how activity in one area
0:12:07 > 0:12:12affects activity in another area and how that affects behaviour.
0:12:14 > 0:12:17The experiment was only meant to help the scientists gain
0:12:17 > 0:12:19greater knowledge about the autistic brain.
0:12:21 > 0:12:24But then, something unexpected happened.
0:12:27 > 0:12:32John was given transcranial magnetic stimulation, or TMS.
0:12:32 > 0:12:36Magnetic coils were placed next to his head to generate
0:12:36 > 0:12:40minute electrical currents in the brain and alter its activity.
0:12:42 > 0:12:46The researchers targeted different regions of John's brain to see
0:12:46 > 0:12:50whether interfering with his brain activity had
0:12:50 > 0:12:56- any effect on his behaviour.- They would test me after the session.
0:12:56 > 0:12:59I would go home, kind of not knowing what to expect.
0:13:00 > 0:13:02At first, there was no result,
0:13:02 > 0:13:06but then they targeted the dorsolateral prefrontal cortex,
0:13:06 > 0:13:11a region involved in flexible thinking and abstraction,
0:13:11 > 0:13:14and something dramatic happened.
0:13:14 > 0:13:15Somehow, I became different.
0:13:19 > 0:13:24He contacted us, very excited, to say, you know,
0:13:24 > 0:13:27"The effects of the stimulation seemed to have unlocked
0:13:27 > 0:13:30"something and the effects are still lasting
0:13:30 > 0:13:33"and I now can do things that I could never do!"
0:13:38 > 0:13:44After TMS, I was able to sort of read signals from other people
0:13:44 > 0:13:46and understand what was going on.
0:13:48 > 0:13:53So I listened to that, fascinated by it, and thought, OK, well, whatever.
0:13:53 > 0:13:55It'll go away. But it didn't.
0:13:55 > 0:13:58It actually remained something that had really
0:13:58 > 0:14:00fundamentally changed in him.
0:14:03 > 0:14:06Somehow, and entirely accidentally,
0:14:06 > 0:14:10the TMS had unlocked a whole new world for John.
0:14:10 > 0:14:11A vegetable sandwich to bring home...
0:14:11 > 0:14:16'I'd be tempted to say I couldn't read people and now I can,
0:14:16 > 0:14:18'but that's not really true.'
0:14:18 > 0:14:21- OK, how about a full-sized... One of them?- Sure.
0:14:21 > 0:14:25It's more accurate to say I had no idea there were these
0:14:25 > 0:14:28messages emanating from other people.
0:14:30 > 0:14:34'TMS showed me those messages, and now that
0:14:34 > 0:14:38'I'm aware that they're out there, everything I do is different.'
0:14:39 > 0:14:42All of a sudden, you can walk around and engage the world...
0:14:43 > 0:14:45'..and it's a big, big thing.'
0:14:46 > 0:14:47OK, thanks.
0:14:50 > 0:14:53We don't know exactly what happened neurobiologically
0:14:53 > 0:14:55but I think it now offers the opportunity for us
0:14:55 > 0:15:00to understand what behavioural modifications, what interventions
0:15:00 > 0:15:04might be possible to learn from him that we can then teach others.
0:15:07 > 0:15:11John's transformation is a reminder that all
0:15:11 > 0:15:13the activities of the human brain,
0:15:13 > 0:15:18including the subtle interplay of emotions and relationships,
0:15:18 > 0:15:21are rooted in the detailed patterns
0:15:21 > 0:15:24of trillions of electrochemical signals.
0:15:32 > 0:15:34Somehow, humans can look at each other
0:15:34 > 0:15:38and study the arrangement of facial muscles
0:15:38 > 0:15:42and then process that information into an understanding of
0:15:42 > 0:15:45other people's thoughts and emotions.
0:15:47 > 0:15:52It's an astonishing skill because the cues are so subtle
0:15:52 > 0:15:55and the processing is so rapid
0:15:55 > 0:15:59that the whole operation runs under your radar.
0:16:01 > 0:16:06It only takes 33 milliseconds for your brain to process basic
0:16:06 > 0:16:12information about someone's facial expression and start reacting to it.
0:16:12 > 0:16:15So we're going to put one electrode right above your eyebrow...
0:16:15 > 0:16:16'So how does it do that?'
0:16:16 > 0:16:19..and the other right on your cheek. There we go. Great.
0:16:22 > 0:16:27'I've invited a group of people to run an experiment.
0:16:27 > 0:16:30'I've wired up to a machine that measures movements in their
0:16:30 > 0:16:35'facial muscles and I've asked them to look at photographs of faces.'
0:16:44 > 0:16:47When participants are looking at a photograph with a smile
0:16:47 > 0:16:51or a frown, we see this activity on the graph,
0:16:51 > 0:16:54which indicates that their own facial muscles are moving.
0:16:55 > 0:16:56Why?
0:16:59 > 0:17:02Well, it turns out that they are automatically mirroring,
0:17:02 > 0:17:06with their own faces, the expressions that they're seeing.
0:17:09 > 0:17:14- That was fun, right, the last one? - Yeah.- Yeah, that was a fun test!
0:17:14 > 0:17:16But what purpose does this mirroring serve?
0:17:18 > 0:17:21I've invited a second group of people.
0:17:21 > 0:17:25They're similar to the first group except for one thing.
0:17:32 > 0:17:36This is the most lethal neurotoxin on the planet.
0:17:36 > 0:17:39If you were to ingest even a fraction of this,
0:17:39 > 0:17:42your brain could no longer tell your muscles how to contract,
0:17:42 > 0:17:44and you would die of total paralysis.
0:17:44 > 0:17:48So it seems unlikely that anyone would pay to have this
0:17:48 > 0:17:50injected into themselves, but they do.
0:17:52 > 0:17:55This is known as botulinum toxin or Botox.
0:17:57 > 0:18:00If you put in your forehead muscles, it paralyses them
0:18:00 > 0:18:02to reduce wrinkling.
0:18:04 > 0:18:07But there's a less well-known side-effect.
0:18:11 > 0:18:16When our participants with Botox went through the same tests,
0:18:16 > 0:18:20their facial muscles responded less. No surprise there.
0:18:20 > 0:18:24But replicating an experiment out of Duke University,
0:18:24 > 0:18:27we had both groups look at facial expressions
0:18:27 > 0:18:32and now they were asked to choose the word that best described
0:18:32 > 0:18:34the emotion they were seeing.
0:18:39 > 0:18:41Panic.
0:18:41 > 0:18:43Panicked.
0:18:45 > 0:18:46Upset.
0:18:48 > 0:18:53On average, the Botox group was worse at identifying
0:18:53 > 0:18:54the emotions correctly.
0:18:56 > 0:18:57Sceptical?
0:18:57 > 0:19:01It seems that the lack of feedback from their facial muscles
0:19:01 > 0:19:05impairs their ability to read other people.
0:19:05 > 0:19:10The paralysed faces of Botox users not only makes it hard for us
0:19:10 > 0:19:12to tell what THEY'RE feeling,
0:19:12 > 0:19:17those same frozen muscles make it hard for THEM to read US.
0:19:18 > 0:19:21And that tells us something.
0:19:21 > 0:19:24When I'm happy or sad, part of that feeling
0:19:24 > 0:19:29relies on the unconscious feedback from muscles in my face.
0:19:29 > 0:19:32And our social brains take advantage of that,
0:19:32 > 0:19:36so when we're trying to understand what someone else is feeling,
0:19:36 > 0:19:38we try on their facial expression.
0:19:41 > 0:19:46This automatic mirroring of expressions is just one way
0:19:46 > 0:19:49in which we understand others.
0:19:49 > 0:19:52The brain also has a deeper way,
0:19:52 > 0:19:55one that's best explained at the movies.
0:20:03 > 0:20:05One ticket, please.
0:20:06 > 0:20:08Thank you.
0:20:10 > 0:20:12When we go to the movie theatre,
0:20:12 > 0:20:15we know full well that it's make-believe.
0:20:15 > 0:20:19The people on the screen are just acting.
0:20:19 > 0:20:25And yet, we still react. We gasp and flinch and cry.
0:20:25 > 0:20:26Why do we fall for it?
0:20:33 > 0:20:36To understand why we care about other people getting hurt,
0:20:36 > 0:20:40we need to understand what happens in your brain when you get hurt.
0:20:40 > 0:20:41So imagine that somebody
0:20:41 > 0:20:44were to stab your hand with a syringe needle.
0:20:44 > 0:20:47That activates a network of areas in your brain that we call
0:20:47 > 0:20:50the pain matrix.
0:20:52 > 0:20:56There's no single spot in the brain where pain is processed.
0:20:57 > 0:21:01Instead, the perception of pain arises from several different
0:21:01 > 0:21:03areas networking together.
0:21:03 > 0:21:06Strangely enough,
0:21:06 > 0:21:10this pain matrix is at the heart of how we connect with others.
0:21:13 > 0:21:16Now, when you watch someone else get stabbed,
0:21:16 > 0:21:19your pain matrix becomes activated.
0:21:20 > 0:21:24Not the parts that tell you you've actually been touched,
0:21:24 > 0:21:28but the parts involved in the emotional experience of pain.
0:21:28 > 0:21:33In other words, watching someone else in pain and being in pain
0:21:33 > 0:21:38use the same neural machinery and that's the basis of empathy.
0:21:47 > 0:21:52To empathise with another person is to literally feel their pain.
0:21:55 > 0:21:59You run a compelling simulation of what it would be like
0:21:59 > 0:22:02if you were in that situation.
0:22:02 > 0:22:07And our capacity to do this is why stories and movies and novels
0:22:07 > 0:22:12are so absorbing and why they're so pervasive across human culture
0:22:12 > 0:22:17because whether it's about total strangers or made-up characters,
0:22:17 > 0:22:23you experience their agony and their ecstasy, you fluidly become them
0:22:23 > 0:22:27and live their lives and stand in their vantage points.
0:22:30 > 0:22:33You can tell yourself that the stories aren't real,
0:22:33 > 0:22:37but some neurons deep in your brain can't tell the difference.
0:22:48 > 0:22:52Our capacity to feel another person's pain is part of what
0:22:52 > 0:22:55makes us so good at taking other people's perspective,
0:22:55 > 0:22:59to step out of our shoes and into their shoes, neurally speaking.
0:23:02 > 0:23:05We can't help but connect with others.
0:23:05 > 0:23:09We're hotwired to be extremely social creatures.
0:23:09 > 0:23:14And that raises a question - what would happen
0:23:14 > 0:23:17if the brain were starved of human contact?
0:23:24 > 0:23:28In 2009, peace activist Sarah Shourd
0:23:28 > 0:23:32and her two companions were hiking in the mountains of northern Iraq,
0:23:32 > 0:23:35an area that was at the time peaceful,
0:23:35 > 0:23:39but they accidentally strayed into Iran and they were arrested.
0:23:41 > 0:23:45They pulled us apart and threw us in separate cells and slammed the door.
0:23:45 > 0:23:47And um...
0:23:47 > 0:23:53That was the beginning of the next 410 days of my life in that cell.
0:23:59 > 0:24:03In the early weeks and really months of solitary confinement,
0:24:03 > 0:24:06you're reduced to an animal-like state.
0:24:06 > 0:24:08I mean, you are an animal, in a cage.
0:24:14 > 0:24:18And the majority of your hours are pacing,
0:24:23 > 0:24:27and the animal-like state sort of eventually
0:24:27 > 0:24:30transformed into a more plant-like state.
0:24:32 > 0:24:37When your mind starts to slow down and your thoughts become repetitive.
0:24:44 > 0:24:46Your brain turns on itself
0:24:46 > 0:24:53and it becomes the source of your worst pain and your worst torture.
0:25:00 > 0:25:02I would relive every detail of my life.
0:25:04 > 0:25:08And eventually, you run out of memories and you've told them
0:25:08 > 0:25:12all to yourself so many times and it doesn't take that long.
0:25:12 > 0:25:17Extreme social deprivation causes deep psychological pain.
0:25:17 > 0:25:21Without interaction, the brain suffers.
0:25:22 > 0:25:26Solitary confinement is designed to eat away at
0:25:26 > 0:25:29and really attack what essentially makes us human.
0:25:33 > 0:25:37Sarah's brain used the scant sensory information it had
0:25:37 > 0:25:40to construct a reality.
0:25:41 > 0:25:44The sun would come in at a certain time of day at an angle
0:25:44 > 0:25:49through my window and all of the little dust particles in my cell
0:25:49 > 0:25:51were illuminated by the sun.
0:25:53 > 0:25:56I saw all of those particles of dust as being
0:25:56 > 0:25:59other human beings occupying the planet.
0:25:59 > 0:26:03And they were in the stream of life, they were interacting, they
0:26:03 > 0:26:07were bouncing off one another, they were doing something collective.
0:26:11 > 0:26:15And I saw myself as off in a corner, you know,
0:26:15 > 0:26:18walled off by myself, out of the stream of life.
0:26:24 > 0:26:30In September 2010, after 410 days in solitary confinement,
0:26:30 > 0:26:33Sarah was finally released and allowed to rejoin the world.
0:26:36 > 0:26:41But for a long time, she suffered from extreme post-traumatic stress.
0:26:44 > 0:26:48The philosopher Martin Heidegger said we can't talk about being,
0:26:48 > 0:26:51we can only talk about being in the world.
0:26:51 > 0:26:56In other words, the world around you is a part of who you are.
0:26:58 > 0:27:01In a vacuum, you lose your sense of self.
0:27:05 > 0:27:08It's not easy for science to study people
0:27:08 > 0:27:11while they're experiencing solitary confinement,
0:27:11 > 0:27:14but a simple experiment designed by neuroscientist
0:27:14 > 0:27:16Naomi Eisenberger can give us
0:27:16 > 0:27:21an insight into what's happening in the brain when we feel excluded.
0:27:24 > 0:27:27It's based on a game of catch.
0:27:29 > 0:27:33While volunteers played a computer game of catch, Eisenberger
0:27:33 > 0:27:35and her team scanned their brains.
0:27:37 > 0:27:41The volunteers thought the other characters were controlled by other
0:27:41 > 0:27:45participants, but in fact, they were just part of a computer program.
0:27:47 > 0:27:50At first, the other characters played nicely,
0:27:50 > 0:27:54but after a while, they'd cut the volunteer out of the game.
0:27:54 > 0:27:57And simply play between themselves.
0:27:59 > 0:28:05She found that being left out of the game activated the pain matrix.
0:28:09 > 0:28:12Not getting the ball might seem insignificant,
0:28:12 > 0:28:17but to the brain, social rejection is so meaningful that it hurts.
0:28:22 > 0:28:25But that pain, in turn, is useful.
0:28:28 > 0:28:31It pushes us in the direction of bonding with others.
0:28:37 > 0:28:40We all seek out alliances.
0:28:40 > 0:28:44We join with friends, with family,
0:28:44 > 0:28:47with colleagues.
0:28:47 > 0:28:49It could be which team we support.
0:28:51 > 0:28:53What style we go for.
0:28:54 > 0:28:57What our hobbies are.
0:28:57 > 0:29:00It gives comfort to belong to a group.
0:29:00 > 0:29:05And that gives us a critical clue into our success as a species.
0:29:07 > 0:29:10Survival of the fittest isn't just about individuals.
0:29:10 > 0:29:13It's also about groups.
0:29:13 > 0:29:17We're safer, we're more productive, we overcome challenges.
0:29:19 > 0:29:23The drive to work in groups has helped human populations
0:29:23 > 0:29:27thrive across the planet and build entire civilisations.
0:29:33 > 0:29:37And yet, there's a flipside to this drive to come together.
0:29:37 > 0:29:40Because for every ingroup, there are outsiders.
0:29:44 > 0:29:47And the consequences of that can be very dark.
0:29:52 > 0:29:56History is plagued with examples of one group turning on another
0:29:56 > 0:30:00that was defenceless and posed no threat.
0:30:03 > 0:30:06If you were to look at my family tree,
0:30:06 > 0:30:10you would see that most of the branches end in the early 1940s.
0:30:10 > 0:30:15This is because my family is ethnically Jewish.
0:30:15 > 0:30:19That small social marker was enough to prompt Nazi genocide.
0:30:23 > 0:30:25Under normal circumstances,
0:30:25 > 0:30:29you wouldn't find it conscionable to go and murder your neighbour.
0:30:29 > 0:30:33So what is it that allows hundreds or thousands of people to
0:30:33 > 0:30:36suddenly do exactly that?
0:30:36 > 0:30:41What is it about certain situations that short-circuits the normal
0:30:41 > 0:30:43social functioning of the brain?
0:30:47 > 0:30:52While the Nazi holocaust was on an unprecedented scale,
0:30:52 > 0:30:54it wasn't unique.
0:30:54 > 0:30:58Genocide continued to occur all over the world
0:30:58 > 0:31:02and within a generation, it returned to Eastern Europe.
0:31:02 > 0:31:05This time, it was in Yugoslavia.
0:31:15 > 0:31:22The Bosnian war from 1992 to '95 saw atrocities on both sides.
0:31:22 > 0:31:26In one of the worst, more than 100,000 Bosnians Muslims,
0:31:26 > 0:31:28known as Bosniaks,
0:31:28 > 0:31:32were slaughtered by Serbians in actions known as ethnic cleansing.
0:31:35 > 0:31:39One of the most horrible incidents happened here at Srebrenica.
0:31:43 > 0:31:46Over the course of just ten days,
0:31:46 > 0:31:498,000 people were systematically killed.
0:31:51 > 0:31:55How does something like this happen?
0:31:55 > 0:31:59Here in 1995, thousands of Bosniaks took refuge inside this
0:31:59 > 0:32:01United Nations compound
0:32:01 > 0:32:04because this village was surrounded by siege forces.
0:32:06 > 0:32:08But then, on July 11th,
0:32:08 > 0:32:12the UN commanders made the decision to expel all the refugees
0:32:12 > 0:32:16and they delivered them right into the hands of their enemies,
0:32:16 > 0:32:18who were waiting just outside this gate.
0:32:19 > 0:32:23Women were raped and men were executed
0:32:23 > 0:32:28and even children were killed and this was just the beginning of what
0:32:28 > 0:32:32would be the largest genocide on European soil since the Holocaust.
0:32:42 > 0:32:44The Dutch were there.
0:32:44 > 0:32:47I mean, the world was there, the UN,
0:32:47 > 0:32:50the Serbs were there as perpetrators.
0:32:50 > 0:32:52Everything was mixed.
0:32:52 > 0:32:55The refugees were there, the babies were crying.
0:32:56 > 0:32:59I was there, being protected with that UN ID card that said
0:32:59 > 0:33:02UN Language Assistant, whatever...
0:33:04 > 0:33:08Hasan Nuhanovic's status as a UN translator made him
0:33:08 > 0:33:10part of a protected group.
0:33:12 > 0:33:17But his family members were marked out by their identity as Muslims.
0:33:17 > 0:33:22At that very moment when my family was being sent out of the compound
0:33:22 > 0:33:26to actually die, I lost my mother, my brother and my father.
0:33:26 > 0:33:30You know, like, you are in a situation where your family
0:33:30 > 0:33:32is being killed.
0:33:32 > 0:33:35And I was thinking, "My God...
0:33:35 > 0:33:38"Why?"
0:33:40 > 0:33:42One of the most striking things
0:33:42 > 0:33:45is that the perpetrators weren't strangers.
0:33:45 > 0:33:48They were people with whom his family had previously shared
0:33:48 > 0:33:50a great deal.
0:33:51 > 0:33:56The continuation, you know, of the killings, of torture,
0:33:56 > 0:34:01was perpetrated by our neighbours.
0:34:01 > 0:34:05You know, the very people we had been living with for decades.
0:34:08 > 0:34:12They were capable of killing their own school friends.
0:34:14 > 0:34:18I remember they said they arrested a dentist who was a Bosniak,
0:34:18 > 0:34:20the best dentist in the town.
0:34:22 > 0:34:25They tied him up for a light pole, like this.
0:34:25 > 0:34:28In front of the post office. He was hanging there like this.
0:34:28 > 0:34:34And they beat him with a metal bar, they broke his spine.
0:34:34 > 0:34:39And he was there, dying for days, while Serb children went to school.
0:34:39 > 0:34:43Walking by his body, you know.
0:34:45 > 0:34:48I mean, there are universal values
0:34:48 > 0:34:53and these universal values are kind of very basic.
0:34:53 > 0:34:54Don't kill.
0:34:56 > 0:35:01April '92, this... Don't kill...
0:35:01 > 0:35:03suddenly disappeared.
0:35:03 > 0:35:05It was like - go and kill.
0:35:05 > 0:35:07It was allowed to kill.
0:35:18 > 0:35:22This is where Hasan's family is buried and each year,
0:35:22 > 0:35:25there are new bodies that are found and identified
0:35:25 > 0:35:26and they're brought here.
0:35:26 > 0:35:29Many of these graves are fresh.
0:35:32 > 0:35:35And across the human species, this is just one genocide of many.
0:35:37 > 0:35:42Genocides keep happening. Rwanda, Darfur, Nanking,
0:35:42 > 0:35:46Armenia... And my interest is in understanding why.
0:35:49 > 0:35:53Traditionally, we ask this question through the lens of history
0:35:53 > 0:35:57or economics or politics, and those are all important vantage points,
0:35:57 > 0:36:01but I think for a complete picture, one more lens is needed.
0:36:01 > 0:36:05We need to understand genocide as a neural phenomenon.
0:36:12 > 0:36:15I've been researching this back in my laboratory
0:36:15 > 0:36:20and here is my main question - when we interact with someone,
0:36:20 > 0:36:24does our brain function differ according to which group they're in?
0:36:27 > 0:36:28For every ingroup we belong to,
0:36:28 > 0:36:32there's at least one group that we don't.
0:36:32 > 0:36:35And that division can be based on anything.
0:36:37 > 0:36:41Race, or gender, or wealth, or religion.
0:36:47 > 0:36:50We put 130 participants in the scanner.
0:36:53 > 0:36:56And here's what they saw - six hands on the screen
0:36:56 > 0:36:58and the computer randomly picks one of these
0:36:58 > 0:37:01and then that hand gets stabbed by a syringe needle.
0:37:06 > 0:37:09Now, that activates the pain matrix, which is what comes online
0:37:09 > 0:37:12when you're in pain or you seem someone else in pain.
0:37:16 > 0:37:17Now, here's the trick.
0:37:17 > 0:37:20We now added a label to each hand -
0:37:20 > 0:37:25Jewish, Christian, Muslim, Hindu, Atheist, Scientologist.
0:37:25 > 0:37:28And the question is - would they care as much
0:37:28 > 0:37:31when they see a member of their outgroup getting stabbed?
0:37:40 > 0:37:42So, here's what we found.
0:37:42 > 0:37:47Here's a subject and when he watched a member of his ingroup getting
0:37:47 > 0:37:51stabbed, there was a large neural response in this area of his brain.
0:37:51 > 0:37:55But when he watched a member of one of his outgroups get stabbed,
0:37:55 > 0:38:00there was essentially a flat line.
0:38:00 > 0:38:02We scanned a range of volunteers
0:38:02 > 0:38:06and there are individual differences, but the trend is clear.
0:38:06 > 0:38:09A single-word label is enough
0:38:09 > 0:38:12to change your brain's basic preconscious response
0:38:12 > 0:38:14to another person in pain.
0:38:14 > 0:38:17In other words, how much you care about them.
0:38:17 > 0:38:20Now, you might have opinions about religion
0:38:20 > 0:38:22and its historical divisiveness,
0:38:22 > 0:38:27but even atheists here care more about other atheists'
0:38:27 > 0:38:30hands getting stabbed than they do about other people.
0:38:30 > 0:38:34So it's not really about religion. It's about which team you're on.
0:38:40 > 0:38:44This is just the first step in understanding how we get to this.
0:38:51 > 0:38:56To understand how groups of people can commit atrocities,
0:38:56 > 0:39:02it can help to look at the behaviour of individuals, like psychopaths.
0:39:02 > 0:39:03Some of the most callous,
0:39:03 > 0:39:09inhumane crimes ever recorded have been committed by psychopaths.
0:39:10 > 0:39:15But what's different about their brains that allows them
0:39:15 > 0:39:17to act that way?
0:39:19 > 0:39:23There are networks in the medial prefrontal cortex that
0:39:23 > 0:39:26underlie social interaction.
0:39:26 > 0:39:30When we interact with other people, this area becomes active.
0:39:32 > 0:39:36But in the brain of someone with extreme psychopathy, this area
0:39:36 > 0:39:39has a lot less activity.
0:39:40 > 0:39:43A psychopath doesn't care about you.
0:39:43 > 0:39:45He might be able to run a simulation
0:39:45 > 0:39:48of what you're going to do or how you might react,
0:39:48 > 0:39:52but when it comes to an emotional understanding
0:39:52 > 0:39:56of what it's like to be you, he doesn't get that.
0:39:56 > 0:40:00To him, you're just an obstacle to be worked around or manipulated,
0:40:00 > 0:40:03rather than a fellow human being.
0:40:03 > 0:40:09So what accounts for genocide? Is it driven by armies of psychopaths?
0:40:09 > 0:40:10Well, that can't be it
0:40:10 > 0:40:14because psychopaths only make up a small fraction of the population,
0:40:14 > 0:40:18but genocide typically engages a wider community.
0:40:18 > 0:40:23So here's the question - how do you get ordinary citizens on board?
0:40:29 > 0:40:33At the University of Leiden in Holland, Dr Lasana Harris
0:40:33 > 0:40:38has been conducting an experiment to understand a piece of this puzzle.
0:40:49 > 0:40:52So now we're going to start the experiment.
0:40:52 > 0:40:56What you're going to see is a bunch of pictures of different people.
0:40:56 > 0:40:59Your job is just to react naturally to those pictures.
0:41:01 > 0:41:03Lasana is looking at activity
0:41:03 > 0:41:07in the brain areas involved in human social interaction,
0:41:07 > 0:41:11in particular the medial prefrontal cortex.
0:41:11 > 0:41:14This comes online when we think about other people.
0:41:14 > 0:41:18It's less active when dealing with something inanimate, like a cup.
0:41:20 > 0:41:24What Lasana found is that this region has a similarly low
0:41:24 > 0:41:28response when we deal with certain types of other people.
0:41:32 > 0:41:34What he sees now are stereotypical
0:41:34 > 0:41:38images of people from different social groups.
0:41:41 > 0:41:44What we see here is that this network of brain regions,
0:41:44 > 0:41:48including medial prefrontal cortex, is less active
0:41:48 > 0:41:52when our participant looks at the homeless people.
0:41:52 > 0:41:54So what this pattern of activity
0:41:54 > 0:41:56suggests is a type of mental avoidance.
0:41:56 > 0:42:00They are not thinking about the mind of the homeless person
0:42:00 > 0:42:02in the same way they thought about the mind
0:42:02 > 0:42:05of the college student that they saw or the businesspeople.
0:42:08 > 0:42:09So if, for instance,
0:42:09 > 0:42:13you imagine that interacting with a homeless person will be unpleasant,
0:42:13 > 0:42:15it will make you feel bad.
0:42:15 > 0:42:18You may feel some demand to donate some of your money
0:42:18 > 0:42:22and all of these unpleasant pressures that come along with it.
0:42:22 > 0:42:26By shutting off the system, you never experience those feelings.
0:42:29 > 0:42:34To a brain that responds this way, homeless people are dehumanised.
0:42:34 > 0:42:39They are viewed more like objects and that can enable us to not care.
0:42:44 > 0:42:47Of course, if you don't properly diagnose this person
0:42:47 > 0:42:49as a human being - which is happening here -
0:42:49 > 0:42:52then the different moral rules we have
0:42:52 > 0:42:55that are reserved for human people may not apply.
0:42:59 > 0:43:01So, under the right circumstances,
0:43:01 > 0:43:05our brain activity can look more like a psychopath's.
0:43:06 > 0:43:10But to understand how we can get to genocide,
0:43:10 > 0:43:14we need to understand one more thing about group behaviour.
0:43:14 > 0:43:17Genocide is only possible
0:43:17 > 0:43:20when dehumanisation happens on a massive scale -
0:43:20 > 0:43:22not just a few individuals,
0:43:22 > 0:43:24but whole sections of the population.
0:43:26 > 0:43:30We are talking about a group of people committing atrocities.
0:43:33 > 0:43:37And if all the members of that perpetrating group are complicit,
0:43:37 > 0:43:40it's as if they have all somehow experienced
0:43:40 > 0:43:42the same reduction in brain activity
0:43:42 > 0:43:44when they think about their outgroup.
0:43:47 > 0:43:51This can be understood and studied like a disease outbreak -
0:43:51 > 0:43:56a kind of group contagion, one that is most often spread deliberately.
0:44:01 > 0:44:04The perfect tool for this job is propaganda.
0:44:04 > 0:44:06It plugs right into neural networks
0:44:06 > 0:44:11and it dials down the degree to which we care about other people.
0:44:11 > 0:44:14Just like all sites of genocide,
0:44:14 > 0:44:16that's what happened in the former Yugoslavia.
0:44:18 > 0:44:21The people who went on to torture and kill their neighbours
0:44:21 > 0:44:24were bombarded with propaganda.
0:44:24 > 0:44:29State-controlled broadcasters demonised the Bosnian Muslims
0:44:29 > 0:44:31with distorted news stories.
0:44:31 > 0:44:33We knew from the beginning
0:44:33 > 0:44:36that somebody is helping the Muslims and arming them.
0:44:36 > 0:44:39They went so far as to claim that the Muslims
0:44:39 > 0:44:42were feeding Serbian children to the lions at the zoo.
0:44:47 > 0:44:51Across place and time, the language of propaganda changes very little.
0:44:51 > 0:44:55It always plays the familiar tune of dehumanisation.
0:44:55 > 0:44:58"Make your enemy less than human.
0:44:58 > 0:45:00"Make him like an animal."
0:45:03 > 0:45:04Propaganda is a weapon.
0:45:08 > 0:45:10And, over the course of human history,
0:45:10 > 0:45:14it's become an art and a science
0:45:14 > 0:45:17and it's become ever more dangerous.
0:45:24 > 0:45:26In our connected age,
0:45:26 > 0:45:31any extremist group can reach millions of people with a keystroke.
0:45:31 > 0:45:35The internet is the perfect carrier for propaganda messages
0:45:35 > 0:45:38to reach the people most likely to act upon them -
0:45:38 > 0:45:40young men.
0:45:44 > 0:45:47The political agendas around us
0:45:47 > 0:45:51actually manipulate the brain activity inside of us.
0:45:52 > 0:45:55So is there any way to stop what has happened in the past
0:45:55 > 0:45:58from continuing into the future?
0:46:01 > 0:46:05One possible solution lies in an 1960s experiment
0:46:05 > 0:46:08that was conducted not in a science lab,
0:46:08 > 0:46:10but a school.
0:46:13 > 0:46:15It was 1968,
0:46:15 > 0:46:19the day after the assassination of Martin Luther King.
0:46:24 > 0:46:26Is there anyone in the United States
0:46:26 > 0:46:28that we do not treat as our brothers?
0:46:28 > 0:46:30- Yeah.- Who?- Black people.
0:46:30 > 0:46:32The black people. Who else?
0:46:32 > 0:46:35Jane Elliott was a teacher in a small town in Iowa
0:46:35 > 0:46:40and she wanted to show her class what prejudice really felt like.
0:46:40 > 0:46:41How are black people treated?
0:46:41 > 0:46:43They don't get anything in this world.
0:46:43 > 0:46:47- Why is that? - Because they are a different colour.
0:46:50 > 0:46:53These two men were in that class.
0:46:53 > 0:46:55This was Rex, back then...
0:46:58 > 0:46:59..and this was Ray.
0:47:01 > 0:47:04How many of you in here have blue eyes?
0:47:05 > 0:47:08OK. How many in here have brown eyes?
0:47:08 > 0:47:11Jane says, "We are going to have this exercise,"
0:47:11 > 0:47:14and she right away launches into the propaganda
0:47:14 > 0:47:16of "blue eyes are better than brown eyes".
0:47:16 > 0:47:20Blue-eyed people are better than brown-eyed people.
0:47:22 > 0:47:26Ray and Rex both had blue eyes.
0:47:27 > 0:47:30You brown-eyed people are not to play
0:47:30 > 0:47:32with the blue-eyed people on the playground
0:47:32 > 0:47:35because you are not as good as blue-eyed people.
0:47:35 > 0:47:39The brown-eyeds were denied privileges given to the blue eyes,
0:47:39 > 0:47:41and they had to wear special collars.
0:47:41 > 0:47:43You begin to notice today
0:47:43 > 0:47:46that we spend a great deal of time waiting for brown-eyed people.
0:47:54 > 0:47:58Do you remember what your own behaviour was like
0:47:58 > 0:48:00when you were on top?
0:48:00 > 0:48:05- I was...tremendously evil to my friends.- How so?
0:48:05 > 0:48:11I was going out of my way to pick on my brown-eyed friends
0:48:11 > 0:48:14for the sake of my own promotion.
0:48:14 > 0:48:16What did you do?
0:48:18 > 0:48:24I recall...telling Mrs Elliott - Jane - that she should keep
0:48:24 > 0:48:27the yardstick at hand in case those brown-eyeds got out of control.
0:48:27 > 0:48:29I don't see the yardstick, do you?
0:48:29 > 0:48:32It's over there.
0:48:32 > 0:48:34Mrs Elliott, you'd better keep that on your desk,
0:48:34 > 0:48:37so as the brown-eyed people don't get out of hand.
0:48:38 > 0:48:42At that time, my hair was quite blonde and my eyes were quite blue,
0:48:42 > 0:48:44and I was the perfect little Nazi.
0:48:45 > 0:48:50I looked for ways to be mean to my friends
0:48:50 > 0:48:56who, minutes or hours earlier, had been very close to me.
0:48:58 > 0:49:02But next day, there was a reversal of fortune.
0:49:04 > 0:49:05Yesterday, I told you
0:49:05 > 0:49:08that brown-eyed people aren't as good as blue-eyed people.
0:49:08 > 0:49:11That wasn't true. I lied to you, yesterday.
0:49:13 > 0:49:15Oh, boy, here we go again.
0:49:15 > 0:49:16The truth is...
0:49:17 > 0:49:20..that brown-eyed people are better than blue-eyed people.
0:49:20 > 0:49:22The person you trust stands before you
0:49:22 > 0:49:27and says, "I was wrong. Now, here's the truth."
0:49:28 > 0:49:32Takes your world and shatters it,
0:49:32 > 0:49:35like you have never had your world shattered before.
0:49:35 > 0:49:39You blue-eyed people are not to play with the brown-eyed people.
0:49:39 > 0:49:41Blue-eyed people, go to the back,
0:49:41 > 0:49:43the brown-eyed people, come to the front.
0:49:46 > 0:49:47It's not fair!
0:49:50 > 0:49:52Tell me a little more about what it was like
0:49:52 > 0:49:54when you were in the down group.
0:49:54 > 0:49:59You have such a sense of loss of personality and self,
0:49:59 > 0:50:01that makes it almost impossible to function
0:50:01 > 0:50:03with what is going on in the room.
0:50:03 > 0:50:06Should the colour of some other person's eyes
0:50:06 > 0:50:08have anything to do you with how you treat them?
0:50:08 > 0:50:10- CLASS: No. - All right, then -
0:50:10 > 0:50:11should the colour of their skin?
0:50:11 > 0:50:13CLASS: No.
0:50:13 > 0:50:17Should you judge people by the colour of their skin?
0:50:17 > 0:50:18CLASS: No.
0:50:19 > 0:50:21If I were just going to riff, guess at it,
0:50:21 > 0:50:24it's that one of the most important things we learn as humans
0:50:24 > 0:50:25is perspective-taking
0:50:25 > 0:50:30and kids don't often get really meaningful exercise in that,
0:50:30 > 0:50:32and when you're forced into understanding
0:50:32 > 0:50:34what it is like to stand in someone else's shoes,
0:50:34 > 0:50:37that opens up a lot of cognitive pathways for you.
0:50:37 > 0:50:41I remember saying something to my dad about a comment he made,
0:50:41 > 0:50:45saying "No, that's not appropriate."
0:50:45 > 0:50:48And it did change within the family.
0:50:48 > 0:50:53But you talk about a little kid making that statement, it's huge.
0:50:53 > 0:50:56But it reaffirmed that you can do that -
0:50:56 > 0:50:58you could begin to change.
0:51:06 > 0:51:09The brilliance of the blue eyes/brown eyes experiment
0:51:09 > 0:51:13is that the teacher, Jane Elliott, switched which group was on top
0:51:13 > 0:51:17and that allowed the students to extract the larger lesson,
0:51:17 > 0:51:20which is that systems of rules can be arbitrary.
0:51:20 > 0:51:25They learned that the truths of the world are not fixed
0:51:25 > 0:51:27and they are not even necessarily truths.
0:51:27 > 0:51:30And this is what empowered the children as they grew
0:51:30 > 0:51:34to see through the smoke and mirrors of other people's political agendas
0:51:34 > 0:51:36and to form their own opinions -
0:51:36 > 0:51:40surely a skill we should be teaching to all of our children.
0:51:41 > 0:51:43Should the colour of some other person's eyes
0:51:43 > 0:51:45have anything to do with how you treat them?
0:51:45 > 0:51:46CLASS: No.
0:51:47 > 0:51:50GUNFIRE
0:51:50 > 0:51:52When people are armed with an understanding
0:51:52 > 0:51:54of how propaganda works,
0:51:54 > 0:51:58the power of propaganda is reduced.
0:51:59 > 0:52:03As we come to understand the deep importance of cooperation,
0:52:03 > 0:52:08we stand a chance of not only reducing dehumanisation,
0:52:08 > 0:52:11but achieving our potential as a species.
0:52:14 > 0:52:17Genocide doesn't have to be the norm.
0:52:25 > 0:52:28Instead, our fundamentally social nature
0:52:28 > 0:52:32can hold the key to our success as a species.
0:52:34 > 0:52:37Our future, our survival,
0:52:37 > 0:52:42is intimately, permanently bound up with that of the people around us.
0:52:45 > 0:52:47Our social drive is at the root
0:52:47 > 0:52:53of extraordinary acts of bravery and generosity.
0:52:55 > 0:52:59Who you are has everything to do with who we are.
0:52:59 > 0:53:02Our brains are so fundamentally wired to interact
0:53:02 > 0:53:06that it is not always clear where each of us begins and ends.
0:53:11 > 0:53:16Our species is more than just seven billion individuals,
0:53:16 > 0:53:17spread out across the planet.
0:53:19 > 0:53:23We are something more like a single, vast super-organism.
0:53:25 > 0:53:29Because what your friends know and love as you
0:53:29 > 0:53:31is really a neural network,
0:53:31 > 0:53:36embedded in a far larger web of other neural networks.
0:53:40 > 0:53:42In this age of digital connection,
0:53:42 > 0:53:46we desperately need to understand the links between humans.
0:53:46 > 0:53:50If we want our civilisations to have a bright future,
0:53:50 > 0:53:53we'll need to understand how human brains interact,
0:53:53 > 0:53:55the dangers and the opportunities,
0:53:55 > 0:53:57because there is no avoiding the truth
0:53:57 > 0:54:00that is etched into our neural circuitry.
0:54:00 > 0:54:02We need each other.
0:54:08 > 0:54:11Next time on The Brain, I am going to look into the future.
0:54:13 > 0:54:18What if the brain could do more? Handle more?
0:54:18 > 0:54:21What if there were other ways for it to operate?
0:54:23 > 0:54:26We will look at how we can use our brains
0:54:26 > 0:54:28to control new kinds of bodies.
0:54:33 > 0:54:38How our sensory experience can be expanded to new horizons.
0:54:40 > 0:54:43We will look at how we might one day separate our minds
0:54:43 > 0:54:44from our physical selves.
0:54:46 > 0:54:49What if the study of the brain could address our mortality?
0:54:49 > 0:54:53What if, in the future, we didn't have to die?
0:54:55 > 0:54:57So, what is next for our brains?
0:54:57 > 0:55:01What do the next thousand years have in store for us?
0:55:01 > 0:55:05And, in the far future, what is the human race going to look like?
0:55:05 > 0:55:07What will we be capable of?
0:55:08 > 0:55:12We are heading for a fundamental change in the relationship
0:55:12 > 0:55:16between the body, the brain and the outside world.
0:55:17 > 0:55:20We are marrying our biology with our technology
0:55:20 > 0:55:25and that is poised to transform who we will be.