0:00:07 > 0:00:10Tonight on Horizon, as part of BBC's sitcom season,
0:00:10 > 0:00:13the science of laughter. THEY LAUGH
0:00:13 > 0:00:15What is it? Why do we love it so much?
0:00:15 > 0:00:17And what has it got to do with comedy?
0:00:20 > 0:00:22But seeing as how the Horizon team aren't that funny
0:00:22 > 0:00:26in and of themselves, they've decided to hire a studio...
0:00:28 > 0:00:29..round up an audience...
0:00:31 > 0:00:33..and asked me to take charge.
0:00:36 > 0:00:40Horizon on laughter, like you've never seen it before.
0:00:40 > 0:00:42HE LAUGHS
0:00:51 > 0:00:53APPLAUSE
0:00:55 > 0:00:57Hello, everyone, I'm Jimmy Carr.
0:00:57 > 0:00:59In case you were wondering, this is still Horizon,
0:00:59 > 0:01:02the proper grown-up BBC science documentary series.
0:01:02 > 0:01:04Don't worry, I'll be on my best behaviour.
0:01:04 > 0:01:08There'll be none of my usual innuendo, because if this works out,
0:01:08 > 0:01:10I might get to meet Professor Brian Cox,
0:01:10 > 0:01:12and I can't tell you how much I love Cox.
0:01:12 > 0:01:14LAUGHTER
0:01:14 > 0:01:16Come on!
0:01:17 > 0:01:18So, I've got some great news -
0:01:18 > 0:01:21science has taken time out from giving your job to a robot,
0:01:21 > 0:01:24designing GM crops and cloning designer babies
0:01:24 > 0:01:26to investigate laughter.
0:01:26 > 0:01:27Rest assured, I'm not in charge.
0:01:27 > 0:01:30When it comes to the science stuff, we've called in the experts.
0:01:30 > 0:01:33We've got a group of eminent laughter scientists -
0:01:33 > 0:01:35yes, that is a real thing -
0:01:35 > 0:01:37and they're here, poised to enlighten.
0:01:37 > 0:01:39It's like Laboratoires Garnier back there.
0:01:39 > 0:01:43- Hello, the scientists. ALL:- Hi.
0:01:43 > 0:01:45We've also visited scientists who make people laugh
0:01:45 > 0:01:47and others who make animals laugh.
0:01:47 > 0:01:49We've caused pain, scanned brains
0:01:49 > 0:01:52and visited some of the least funny places on the planet,
0:01:52 > 0:01:55all in a bid to get to the bottom of laughter.
0:01:55 > 0:01:58And we've got a room full of unsuspecting volunteers,
0:01:58 > 0:02:00who think they're just an audience.
0:02:00 > 0:02:02AUDIENCE LAUGHS
0:02:02 > 0:02:04And that was nervous laughter.
0:02:04 > 0:02:05AUDIENCE LAUGHS LOUDLY
0:02:05 > 0:02:09EB White once said analysing comedy is like dissecting a frog -
0:02:09 > 0:02:12few people are interested and the frog dies.
0:02:13 > 0:02:15But what did he know?
0:02:15 > 0:02:17This is going to be the most fun science show
0:02:17 > 0:02:19since the one where they let Stephen Hawking use
0:02:19 > 0:02:21the Large Hadron Collider as a water slide.
0:02:21 > 0:02:24LAUGHTER Right, let's crack on.
0:02:24 > 0:02:26Probably a good idea to start with some classic jokes.
0:02:35 > 0:02:37Two monkeys in a bath.
0:02:37 > 0:02:40One says to the other, "Ooh-ooh-ooh, ah-ah-ah."
0:02:40 > 0:02:42The other says, "Well, put the cold tap on, then."
0:02:44 > 0:02:45How do you make a cat go woof?
0:02:46 > 0:02:48Pour petrol on it and light it.
0:02:54 > 0:02:55These are the clean ones.
0:02:57 > 0:03:00I was walking with my wife when I saw six men kicking and punching
0:03:00 > 0:03:03my mother-in-law. My wife said, "Aren't you going to help?"
0:03:03 > 0:03:05I said, "No, six should be enough."
0:03:07 > 0:03:10A policeman came to my front door and said,
0:03:10 > 0:03:13"I'm sorry, sir, but it looks like your wife's been in an accident."
0:03:13 > 0:03:15I said, "I know, but she's got a cracking personality."
0:03:17 > 0:03:21Now, here's a question you never hear a stand-up comedian ask.
0:03:21 > 0:03:23Why did you laugh at those jokes?
0:03:23 > 0:03:25Does anyone have any ideas on why they laughed?
0:03:25 > 0:03:26I hate cats.
0:03:28 > 0:03:30"I hate cats" is a very good answer.
0:03:30 > 0:03:31I'm sure that's not the case, though,
0:03:31 > 0:03:34that's just another joke on top of that one, so...
0:03:34 > 0:03:36- Any ideas on why you laughed? - Nostalgia.- Because it's funny.
0:03:36 > 0:03:38Nostalgia is a very good one, yeah,
0:03:38 > 0:03:40cos they're old classic school jokes,
0:03:40 > 0:03:41and the familiarity of that.
0:03:41 > 0:03:45That is kind of a...that's a reason sometimes. Any other...
0:03:45 > 0:03:48- thoughts?- Breaking the ice?
0:03:48 > 0:03:50Well, I suppose it is, yeah, that social activity.
0:03:50 > 0:03:53I think we're going to talk about that later on - that idea that
0:03:53 > 0:03:55laughter as a kind of group activity.
0:03:55 > 0:03:57Don't panic, we're going to explain all this.
0:03:59 > 0:04:01This is Horizon, so let's throw some science at the problem.
0:04:05 > 0:04:07University College London...
0:04:08 > 0:04:10..boasting impressive neoclassical architecture
0:04:10 > 0:04:12and a solid academic heritage.
0:04:14 > 0:04:16And, more recently, it's gained a reputation as somewhere
0:04:16 > 0:04:20where laughter is taken very seriously indeed.
0:04:21 > 0:04:22THEY LAUGH
0:04:22 > 0:04:25Today, Professor Sophie Scott...
0:04:26 > 0:04:29..is gathering raw material for her research.
0:04:30 > 0:04:33What we're just going to do is go through some videos
0:04:33 > 0:04:38- and just really find some stuff that makes you laugh, OK?- OK.
0:04:38 > 0:04:41Cos the point of this is, I don't really care what it is,
0:04:41 > 0:04:44I'd just like to collect some really nice laughter from you.
0:04:46 > 0:04:48And to ensure a perfect recording...
0:04:49 > 0:04:52..she's using UCL's anechoic chamber.
0:04:52 > 0:04:54It just means no echo.
0:04:54 > 0:04:57What we're doing here is we're recording somebody
0:04:57 > 0:04:58laughing spontaneously.
0:04:59 > 0:05:00Get nice and comfortable.
0:05:01 > 0:05:05So, I'm playing her something, which we're both fairly confident
0:05:05 > 0:05:07is going to make her laugh.
0:05:07 > 0:05:08VOLUNTEER LAUGHS
0:05:08 > 0:05:11I just got really interested that everything done on emotions
0:05:11 > 0:05:14is negative, and it turned out that the psychologist Paul Ekman
0:05:14 > 0:05:17had suggested that there might well be positive emotions,
0:05:17 > 0:05:19which might actually be basic emotions.
0:05:19 > 0:05:22And in fact he'd said they may well be primarily conveyed
0:05:22 > 0:05:25with the voice, so I thought, "Brilliant, that's what I do".
0:05:25 > 0:05:29Sophie discovered that laughter is something all humans understand,
0:05:29 > 0:05:32regardless of location, culture or language.
0:05:32 > 0:05:33VOLUNTEER LAUGHS
0:05:33 > 0:05:37I think it's really important to study laughter because first of all,
0:05:37 > 0:05:39it's a basic expression of emotion.
0:05:39 > 0:05:41It's a non-verbal expression of emotion,
0:05:41 > 0:05:44but it's one we drop into all the time.
0:05:44 > 0:05:47VOLUNTEER LAUGHS LOUDLY
0:05:47 > 0:05:50We drop into this old mammal vocal behaviour,
0:05:50 > 0:05:53to do a lot of the emotional work of an interaction.
0:05:53 > 0:05:56VOLUNTEER LAUGHS
0:05:57 > 0:06:00Right, I found a really nice bit of laughter and then I lost it again,
0:06:00 > 0:06:01so that's what I'm trying to do.
0:06:01 > 0:06:03VOLUNTEER LAUGHTER CONTINUES
0:06:03 > 0:06:06There we go. Wasn't that lovely?
0:06:08 > 0:06:10I realise that being delighted by a spectrogram
0:06:10 > 0:06:12is sort of niche interest.
0:06:16 > 0:06:19Well, fascinating stuff. And she's here to talk about her research.
0:06:19 > 0:06:22Ladies and gentlemen, please welcome to the studio
0:06:22 > 0:06:24Professor Sophie Scott.
0:06:26 > 0:06:29- Hello. Proper science. - Proper science.
0:06:29 > 0:06:32- Hello, Professor Sophie Scott, how are you?- I'm fine, thank you.
0:06:32 > 0:06:35OK, so, you're saying everyone laughs?
0:06:35 > 0:06:36As far as we can tell,
0:06:36 > 0:06:39when we have done some cross-cultural work on this,
0:06:39 > 0:06:41wherever you go in the world, people recognise laughter.
0:06:41 > 0:06:44Even if you go to a culture where people might not laugh in public,
0:06:44 > 0:06:46cos maybe it's rude, they still recognise laughter,
0:06:46 > 0:06:48and they will still do it in some places.
0:06:48 > 0:06:51- Even like Inverness on a bank holiday Monday?- Potentially!
0:06:51 > 0:06:53Technically, I should be able to get laughs out of those people,
0:06:53 > 0:06:56even if, in reality, not the case.
0:06:56 > 0:06:58They might know it when they saw it happening,
0:06:58 > 0:07:01if you made someone else laugh, they might know what's going on.
0:07:01 > 0:07:03You're saying it's a universal across humanity?
0:07:03 > 0:07:04We don't have the same sense of humour,
0:07:04 > 0:07:06- but we all recognise laughter? - Exactly.
0:07:06 > 0:07:09Humour can be very, very widely varying
0:07:09 > 0:07:11across different times and places.
0:07:11 > 0:07:14Laughter, as a behaviour, stayed pretty constant.
0:07:14 > 0:07:17- OK, can we demonstrate this?- Yes. We've got an example of somebody
0:07:17 > 0:07:19producing some positive expressions of emotion from...
0:07:19 > 0:07:21He's from the Himba tribe in Namibia.
0:07:24 > 0:07:25Hi, hi-hi!
0:07:25 > 0:07:27Hi-hi!
0:07:27 > 0:07:29Hi, hi, hi...
0:07:30 > 0:07:31Any guesses?
0:07:31 > 0:07:35Obviously, if you're watching in Namibia... I mean...
0:07:35 > 0:07:37Couldn't be more bloody obvious, could it?
0:07:37 > 0:07:40Any idea what emotion that was?
0:07:40 > 0:07:42It looked to me like he was clapping backwards.
0:07:43 > 0:07:45Cos it was kind of... It was a weird kind of...
0:07:45 > 0:07:47So, what he was doing is expressing triumph.
0:07:47 > 0:07:50So, the sort of... Imagine that you all really like football
0:07:50 > 0:07:52and the football team that you like has just scored a goal.
0:07:52 > 0:07:54- Make the sound. - AUDIENCE CHEER
0:07:54 > 0:07:56So, that's what you tend to find in the UK,
0:07:56 > 0:07:59people making a triumphant noise sensibly, so like a whoo sound.
0:07:59 > 0:08:01And that's not the noise the Himba make,
0:08:01 > 0:08:03and it's not cross-culturally recognised.
0:08:03 > 0:08:05Let's have another look at this guy.
0:08:05 > 0:08:08- Hi, hi-hi! - HE LAUGHS
0:08:08 > 0:08:11AUDIENCE LAUGHS
0:08:12 > 0:08:14OK, so at the end there, did we all get what was he doing?
0:08:14 > 0:08:16Yeah.
0:08:16 > 0:08:17So, that's uni...
0:08:17 > 0:08:19That's in every culture around the world, the laugh is...
0:08:19 > 0:08:21You'd be able to tell someone was laughing?
0:08:21 > 0:08:23Yes, you would know what was happening.
0:08:23 > 0:08:26The idea with basic expressions of emotion is that they reflect
0:08:26 > 0:08:28something about our evolutionary history, we share them
0:08:28 > 0:08:31with other mammals. Things like fear, anger, disgust, sadness.
0:08:31 > 0:08:33You find those in other mammals.
0:08:33 > 0:08:36So, anger in a dog's face isn't that different from anger
0:08:36 > 0:08:37in a human face.
0:08:39 > 0:08:41It's possible that we need to add laughter
0:08:41 > 0:08:43to this set of basic emotions.
0:08:43 > 0:08:46Right. So, not everyone laughs at the same things, obviously,
0:08:46 > 0:08:49we all have a different sense of humour. Take a look.
0:09:00 > 0:09:02Americans don't tend to really know that much about the world,
0:09:02 > 0:09:04so they don't get other people so much.
0:09:04 > 0:09:08At the moment, the in-thing is about quail birds.
0:09:08 > 0:09:11Just someone that's a grown man, maybe acting like a child.
0:09:12 > 0:09:15Excuse me. Too much gas.
0:09:15 > 0:09:20Armenians are famous for having a good sense of humour, and...
0:09:20 > 0:09:21Yeah.
0:09:23 > 0:09:27Got a new car. They say she's probably got a quail farm.
0:09:27 > 0:09:29What makes me laugh is cheeky banter.
0:09:29 > 0:09:33Squirrels, cats, ravens eating chips.
0:09:33 > 0:09:36I think the British humour is so sharp and so cutting.
0:09:36 > 0:09:39Do you want to hear a joke about helium? Hee-hee-hee.
0:09:39 > 0:09:42Our satire is more like a gentle satire.
0:09:42 > 0:09:46In the Philippines, we make fun of dumb people.
0:09:46 > 0:09:49It's like trying to explain what makes a man's heart beat
0:09:49 > 0:09:53when he sees a blue-eyed blonde with amazing jugs.
0:09:53 > 0:09:56If you're looking good, you've probably...
0:09:56 > 0:10:00Got a few quail birds...in your purse!
0:10:00 > 0:10:03British people are famous for self-laughing.
0:10:03 > 0:10:05Jimmy Carr's one-liners.
0:10:05 > 0:10:07He's my favourite comedian I know of.
0:10:07 > 0:10:09"We in America, we wash hands."
0:10:09 > 0:10:12And the attendant guy turns to him and says,
0:10:12 > 0:10:14"You know we in Lithuania, we don't pee on our hands."
0:10:14 > 0:10:16What do you do with a dead chemist?
0:10:16 > 0:10:17You barium.
0:10:17 > 0:10:19And you end up wanting to look like a quail
0:10:19 > 0:10:21because you're worth a lot of money.
0:10:22 > 0:10:27So, it's a pain au chocolat meeting a croissant and he's asking,
0:10:27 > 0:10:30"Why are you so weird? Why do you have a moon shape?"
0:10:30 > 0:10:33And the other one says, "What are you talking about?
0:10:33 > 0:10:36"Because you have, like, shit all over your ass."
0:10:38 > 0:10:40SHE SPEAKS FRENCH
0:10:48 > 0:10:51So, laughter is universal but what we laugh at
0:10:51 > 0:10:53is cultural and personal.
0:10:53 > 0:10:56Sophie, everyone does it, everyone understands what it means,
0:10:56 > 0:10:58but what actually is laughter?
0:10:58 > 0:11:00Laughter's more like a different way of breathing
0:11:00 > 0:11:02than it as anything else. So, what we are all doing right now,
0:11:02 > 0:11:05hopefully, is using the intercostal muscles,
0:11:05 > 0:11:08the muscles between our ribs, to get air in and out of our bodies.
0:11:08 > 0:11:09It's called metabolic breathing. Exactly.
0:11:09 > 0:11:11You breathe in, you breathe out.
0:11:11 > 0:11:13Air's being drawn in and then squeezed back out again.
0:11:13 > 0:11:16- I'm good at this.- So, were I to look at your chest wall moving...
0:11:16 > 0:11:18Well, that feels weird.
0:11:18 > 0:11:20I've over-thought it.
0:11:20 > 0:11:23- Go on. My chest wall is moving in and out...- You keep going with that.
0:11:23 > 0:11:26You'd see this almost sinusoidal movement, this very smooth movement.
0:11:26 > 0:11:28You start doing it the minute you're born,
0:11:28 > 0:11:30that's it the whole rest of your life.
0:11:30 > 0:11:32When we start laughing, those same muscles start to contract.
0:11:32 > 0:11:37They're really large deflections, just squeezing air out of you,
0:11:37 > 0:11:39and that's basically all laughter is.
0:11:39 > 0:11:41It's an extremely primitive way of making a sound.
0:11:41 > 0:11:44Ultimately, if you couldn't stop laughing, it'd kill you.
0:11:44 > 0:11:47- Yeah.- Basically, I'm a deadly weapon, is what you're saying.
0:11:47 > 0:11:49You definitely are. It's just squeezing air out of you,
0:11:49 > 0:11:52it stops you breathing, it stops you talking, it's trying to kill you.
0:11:52 > 0:11:55- And we've rigged some people up, so we can show this.- Exactly.
0:11:55 > 0:11:58And what we'll notice is, hopefully, if you can make them laugh,
0:11:58 > 0:12:00that both the very fine movement you get during talking
0:12:00 > 0:12:04and the smooth movement that you get during breathing, should go away.
0:12:04 > 0:12:06And instead, what we get is just these big zigzags
0:12:06 > 0:12:08as air's just being squeezed out of you.
0:12:08 > 0:12:10OK, so, are we looking at them breathing first?
0:12:10 > 0:12:12Well, hopefully they're already breathing.
0:12:12 > 0:12:14- OK, so are they breathing? - Hopefully!
0:12:14 > 0:12:17- I can see them breathing.- They're breathing now and you're happy?
0:12:17 > 0:12:20Sinead, your PhD assistant... Hi, Sinead. How are you?
0:12:20 > 0:12:23So, you're saying those two ladies are alive?
0:12:23 > 0:12:25- Fantastic.- This is incredible science.
0:12:26 > 0:12:28- So, I've got to try and make them laugh now?- Please.
0:12:28 > 0:12:30Right, I'll do some jokes from over here.
0:12:30 > 0:12:33We've got a performance area with... Yay, everyone.
0:12:33 > 0:12:36- AUDIENCE:- Yay!- OK.
0:12:36 > 0:12:39I look like this, obviously, because my dad is Irish and my mum is...
0:12:39 > 0:12:41Roger Federer.
0:12:41 > 0:12:43LAUGHTER
0:12:43 > 0:12:46I feel like you're laughing at me, not with me, there.
0:12:46 > 0:12:50A nurse finds a rectal thermometer in her pocket and thinks,
0:12:50 > 0:12:51"Some arsehole's got my pen."
0:12:54 > 0:12:56I got talking to a North African girl recently
0:12:56 > 0:12:58in her native language, for hours.
0:12:58 > 0:13:00We just...clicked.
0:13:03 > 0:13:04That's enough of that.
0:13:04 > 0:13:07We should be able to see some sort of difference then, so...
0:13:07 > 0:13:09- Did you see anything there? Oh. - Oh, look at that.
0:13:09 > 0:13:11Can you see at the bottom there, she's breathing,
0:13:11 > 0:13:14and then you're really making her laugh. Can you see the big zigzags?
0:13:14 > 0:13:16- Then breath, breath, breath and then zigzags again.- Hang on,
0:13:16 > 0:13:18I'm going over to have a look. I'm going to use
0:13:18 > 0:13:21one of these technical fingers. So, that was the laugh?
0:13:21 > 0:13:23- Yes, that's the laugh there. - That's a pretty big laugh.
0:13:23 > 0:13:25That's pretty big, and there's a big...
0:13:25 > 0:13:28If you look at the top as well, the person at the top is also laughing.
0:13:28 > 0:13:30Yeah, but she wasn't really into it. LAUGHTER
0:13:30 > 0:13:32- You were funny earlier. - It feels like, if I was...
0:13:32 > 0:13:34If I'm going to work as an assassin,
0:13:34 > 0:13:37and that is ultimately the goal of this show,
0:13:37 > 0:13:41I would not be able to kill the lady in the yellow,
0:13:41 > 0:13:44but the lady in the orange, I think...
0:13:44 > 0:13:46- Yeah.- You better watch yourself, love.
0:13:46 > 0:13:48OK, so, supplemental to that,
0:13:48 > 0:13:51if you were to make someone laugh uncontrollably,
0:13:51 > 0:13:53- could it be a dangerous thing? - Well, it can be.
0:13:53 > 0:13:56I mean, it literally is stopping you from breathing.
0:13:56 > 0:13:57It's just squeezing air out of you
0:13:57 > 0:13:59and it's stopping you doing anything else.
0:13:59 > 0:14:01And there's even a postural reflex
0:14:01 > 0:14:03that means that we're all sitting in our chairs,
0:14:03 > 0:14:04we don't just slump to the ground.
0:14:04 > 0:14:06So even when your muscles aren't working,
0:14:06 > 0:14:08they're holding you in place, and that is suppressed
0:14:08 > 0:14:11when you start laughing. That's why you become weak and floppy
0:14:11 > 0:14:14when you're laughing, and that, inevitably, at some point
0:14:14 > 0:14:16you can become helpless with laughter, at which point,
0:14:16 > 0:14:18if a tiger came in or something, there would be a brief window
0:14:18 > 0:14:20when you wouldn't be able to do much about it.
0:14:20 > 0:14:22Well, my mother, weirdly, had a very odd laugh.
0:14:22 > 0:14:25She had a laugh where she made no noise at all
0:14:25 > 0:14:26- and lost muscular control.- Right.
0:14:26 > 0:14:28So she would just literally, kind of...
0:14:28 > 0:14:31And then, with her last bit of energy she would go,
0:14:31 > 0:14:35"Stop, just stop," and obviously you would never stop.
0:14:35 > 0:14:38I think it's part of the reason I got into doing this for a living,
0:14:38 > 0:14:40because it was the most fun thing in the world to...
0:14:41 > 0:14:44Oh, my mum has melted. Genius.
0:14:44 > 0:14:47So, laughter's different, physiologically, to normal speech.
0:14:47 > 0:14:50If you couldn't stop laughing, it could genuinely harm you.
0:14:50 > 0:14:52I believe we have some MRI scans.
0:14:52 > 0:14:54- We do. We're going to start... - Excellent.
0:14:54 > 0:14:57- Science in...- I'm sorry, I didn't have time to get to the doctor's,
0:14:57 > 0:14:59so we're going to quickly go through these now,
0:14:59 > 0:15:01see if I'm going to make it. So, what are we looking at?
0:15:01 > 0:15:03What we're looking at first is...
0:15:03 > 0:15:06We're running the MRI machine like a video camera,
0:15:06 > 0:15:09so you're literally taking a movie of somebody speaking here.
0:15:09 > 0:15:12What she's doing is she is talking her way through some nursery rhymes
0:15:12 > 0:15:15and you can see everything that's happening during speech -
0:15:15 > 0:15:17very complex movements of the tongue,
0:15:17 > 0:15:19you've got the jaw moving up and down, the lips, the soft palate,
0:15:19 > 0:15:22the bit at the back of your nose, the larynx,
0:15:22 > 0:15:23the voice box is moving up and down.
0:15:23 > 0:15:24So, that's speech -
0:15:24 > 0:15:27very complex, nothing like that out there in nature.
0:15:27 > 0:15:29And then if we move on to the next one,
0:15:29 > 0:15:32which should be somebody laughing. It's the same person laughing.
0:15:32 > 0:15:33We made her laugh in the scanner,
0:15:33 > 0:15:36and if you look, none of that is happening, basically.
0:15:36 > 0:15:39She's moving up and down a lot cos her ribcage is moving.
0:15:39 > 0:15:41The tongue is staying in the bottom of the mouth,
0:15:41 > 0:15:45and if you've ever laughed until the back of your throat hurts,
0:15:45 > 0:15:47you can see why that's happening there, cos actually
0:15:47 > 0:15:49you can see she's squeezing the tongue right back up
0:15:49 > 0:15:51against the pharynx,
0:15:51 > 0:15:54so you're squeezing all that air out through an even narrower pipe.
0:15:54 > 0:15:56I'm sorry, what did you nail her to, to get this to happen?
0:15:58 > 0:16:01Who doesn't move their head even slightly when they laugh?
0:16:01 > 0:16:04She's in something that looks disturbingly like
0:16:04 > 0:16:05a kind of sarcophagus.
0:16:05 > 0:16:09She's in something that's holding her head and shoulders in position
0:16:09 > 0:16:12- so we can image all this bit here. - Where is she now?
0:16:12 > 0:16:15She's alive, she's well, she escaped, she made it through.
0:16:17 > 0:16:20She escaped? LAUGHTER
0:16:20 > 0:16:22OK, so laughter is more like an animal call than speaking -
0:16:22 > 0:16:24primal and contagious. OK, I get that.
0:16:24 > 0:16:28So, that's what laughter is, but what exactly is it for?
0:16:28 > 0:16:30Well, thankfully, one scientist has taken time off
0:16:30 > 0:16:32from developing jet boots, to find out.
0:16:38 > 0:16:40Oxford University boasts some of the prettiest academic buildings
0:16:40 > 0:16:42in the world.
0:16:43 > 0:16:45These grand palaces of learning are largely the preserve
0:16:45 > 0:16:47of the humanities.
0:16:47 > 0:16:51But because Professor Robin Dunbar is a scientist,
0:16:51 > 0:16:52he's forced to work here...
0:16:55 > 0:16:57..in this architectural abomination.
0:16:59 > 0:17:02Out of the sight of tourists and university website photographers.
0:17:03 > 0:17:06Here, geographically and aesthetically isolated,
0:17:06 > 0:17:08Dunbar causes people pain.
0:17:12 > 0:17:15Because he claims it throws light on why we laugh.
0:17:19 > 0:17:22So, what we're doing here is we're looking to see whether
0:17:22 > 0:17:27pain threshold increases after you've laughed.
0:17:27 > 0:17:29First, the baseline measurement.
0:17:29 > 0:17:30OK. Now!
0:17:41 > 0:17:42Stop.
0:17:45 > 0:17:46Stop.
0:17:53 > 0:17:55We have a winner.
0:17:55 > 0:17:56Stop.
0:17:56 > 0:17:57Good work.
0:17:58 > 0:18:00And now the fun part.
0:18:23 > 0:18:25Professor Dunbar is an experimental psychologist
0:18:25 > 0:18:28and an evolutionary biologist...
0:18:29 > 0:18:31..which is quite a mouthful.
0:18:31 > 0:18:34But what it means is he's able to both formulate ideas
0:18:34 > 0:18:37about our species development and also test them in a lab.
0:18:39 > 0:18:41And one of his main ideas is about grooming.
0:18:44 > 0:18:48Monkeys and apes create their friendships,
0:18:48 > 0:18:51their relationships with each other and thereby bond their social groups
0:18:51 > 0:18:55by grooming, social grooming - grooming each other.
0:18:55 > 0:18:57It turns out that that light stroking
0:18:57 > 0:19:00triggers an endorphin response in the brain.
0:19:02 > 0:19:05The problem with grooming is it's a one-on-one activity -
0:19:05 > 0:19:08you can only groom one individual at a time.
0:19:08 > 0:19:10So, the problem is how to sort of groom
0:19:10 > 0:19:12with several people simultaneously.
0:19:16 > 0:19:20Robin's theory holds that laughter is effectively remote tickling,
0:19:20 > 0:19:22producing the same chemical high.
0:19:29 > 0:19:31And if he's right, the laughing volunteers in the lab
0:19:31 > 0:19:34will now be flushed with pain-beating endorphins...
0:19:36 > 0:19:38..and they'll beat their previous times
0:19:38 > 0:19:39in the wall-sit test.
0:19:40 > 0:19:41OK?
0:19:43 > 0:19:45Go.
0:19:59 > 0:20:00Stop.
0:20:02 > 0:20:04Stop.
0:20:11 > 0:20:12Stop.
0:20:16 > 0:20:17Stop.
0:20:25 > 0:20:28It's direct evidence that laughter does produce endorphins.
0:20:30 > 0:20:34Yes, you'd normally expect something between, on average, I don't know,
0:20:34 > 0:20:39about five seconds and anything up to 20 seconds increase in time,
0:20:39 > 0:20:41and that's pretty much what we have here.
0:20:41 > 0:20:43All statistically significant.
0:20:47 > 0:20:51So, laughter can help you get through a painful experience,
0:20:51 > 0:20:54which is why you hear so much of it at my shows.
0:20:54 > 0:20:56Ladies and gentlemen, please welcome my next guest,
0:20:56 > 0:20:58evil genius, Professor Robin Dunbar.
0:21:04 > 0:21:06Thanks so much for coming. Take a seat.
0:21:06 > 0:21:08- Hi.- Now, you know Sophie, right? - Yep.
0:21:08 > 0:21:10Of course, all scientists know each other.
0:21:10 > 0:21:11We do, it's a small community.
0:21:11 > 0:21:15So, how did grooming begat laughter?
0:21:16 > 0:21:20Well, essentially, the real problem is that we needed to
0:21:20 > 0:21:24be able to groom, if you like, with more individuals simultaneously
0:21:24 > 0:21:26in order to be able to have much bigger groups
0:21:26 > 0:21:28than is typical of monkeys and apes.
0:21:28 > 0:21:32So, how many in a typical group of monkeys and apes?
0:21:32 > 0:21:35The most social species, baboons, chimpanzees, something like that,
0:21:35 > 0:21:37about 50 is the typical group size.
0:21:37 > 0:21:39And what do they call that, Professor Dunbar?
0:21:39 > 0:21:42- Is it called the Dunbar Number?- Ah.
0:21:42 > 0:21:43What's the Dunbar Number?
0:21:43 > 0:21:46Cos you went ahead and named something after yourself...
0:21:46 > 0:21:48LAUGHTER
0:21:48 > 0:21:50..which is, I mean, ego-wise, pretty terrific.
0:21:50 > 0:21:53- Do they pay you money to say these things?- They do, yeah.
0:21:54 > 0:21:56No, Dunbar's Number is technically
0:21:56 > 0:21:59the number of the size of human groups,
0:21:59 > 0:22:04or the number of friends and family that you have, and that's 150,
0:22:04 > 0:22:08that's three times bigger than the kind of typical biggest groups
0:22:08 > 0:22:10you get in monkeys and apes.
0:22:10 > 0:22:13So, that's because they can individually groom
0:22:13 > 0:22:16other monkeys and apes up to about 50,
0:22:16 > 0:22:18and then they break off and start another group.
0:22:18 > 0:22:20Essentially, that's what ends up happening,
0:22:20 > 0:22:23because if you don't bond with the individuals
0:22:23 > 0:22:29you are part of the group with, the group will gradually split up and...
0:22:30 > 0:22:33..into two separate groups, and that happens with us.
0:22:33 > 0:22:36I mean, if we don't engage constantly with our friends
0:22:36 > 0:22:38and relations and so on,
0:22:38 > 0:22:42gradually those relationships just die quietly away.
0:22:42 > 0:22:44So we have to keep this, kind of what's effectively
0:22:44 > 0:22:47a form of grooming, going.
0:22:47 > 0:22:52And we do it by grooming in the way that monkeys and apes do -
0:22:52 > 0:22:55with the patting and the touch on the shoulder and the cuddling
0:22:55 > 0:22:57and all that kind of stuff.
0:22:57 > 0:22:59We do all that but it's a one-on-one thing
0:22:59 > 0:23:03and you can't do it with more than one person at once.
0:23:03 > 0:23:05Oh, you can. HE LAUGHS
0:23:05 > 0:23:08Welcome to showbusiness, Professor Dunbar.
0:23:08 > 0:23:09But no, I take your point there.
0:23:09 > 0:23:14So the idea of remote tickling, I find very pleasing. The idea that...
0:23:14 > 0:23:17I've kind of, I like to think of myself as a drug dealer,
0:23:17 > 0:23:19but the drug that I'm dealing is endorphins,
0:23:19 > 0:23:20and you've already got the drugs on you
0:23:20 > 0:23:23and I'm just bringing the kind of release mechanism
0:23:23 > 0:23:26- that saves on the transport costs. - It does.
0:23:26 > 0:23:30But, I mean, remember endorphins are related to morphine
0:23:30 > 0:23:32and the opiates in general,
0:23:32 > 0:23:36and that's why you get this kind of light-headed kind of relaxed feeling
0:23:36 > 0:23:38from them, they give you an opiate high.
0:23:38 > 0:23:40- So, you're saying we should try drugs?- Yeah, um...
0:23:40 > 0:23:41You spend all day...
0:23:41 > 0:23:45But the difference with endorphins is you don't get addicted to them
0:23:45 > 0:23:49in the way that you do the normal kind of morphine opiate-type drugs.
0:23:49 > 0:23:51Chemically, they're just slightly different,
0:23:51 > 0:23:54so you don't suffer that kind of physiological addiction.
0:23:54 > 0:23:58But the point is that laughter triggers that system,
0:23:58 > 0:24:02and then allows you in effect to groom with several other people
0:24:02 > 0:24:04at the same time,
0:24:04 > 0:24:07so it then becomes a much more efficient use of time.
0:24:07 > 0:24:12So, we can use the same amount of social time during the day,
0:24:12 > 0:24:14but groom with many more people.
0:24:14 > 0:24:17- Fantastic, so that allows us to have bigger groups...- Yeah.
0:24:17 > 0:24:20- ..and therefore to specialise... - Well, then you can have
0:24:20 > 0:24:23all the things that emerged out of our history, as it were,
0:24:23 > 0:24:24you know, sort of...
0:24:24 > 0:24:27You can have culture because you've got many more minds
0:24:27 > 0:24:31to create novel ideas - write books, tell jokes...
0:24:31 > 0:24:35Excellent. So, laughter is remote grooming, it's a social activity,
0:24:35 > 0:24:37and you're actually 30 times more likely to laugh
0:24:37 > 0:24:39when you're with other people.
0:24:39 > 0:24:41It's an intensely social activity, yes.
0:24:41 > 0:24:46I mean, it's this extraordinary contagion effect of it.
0:24:46 > 0:24:51So you could tell a joke in some language that I don't understand
0:24:51 > 0:24:54and everybody else laughs, I cannot help but laugh with you.
0:24:54 > 0:24:57I simply don't know why I'm laughing, but I have to do it.
0:24:57 > 0:24:59I weirdly have a thing in my relationship where we watch
0:24:59 > 0:25:02certain shows together that I'd never dream of watching
0:25:02 > 0:25:04without the other half.
0:25:04 > 0:25:06And there's a thing about if I do watch something on my own
0:25:06 > 0:25:10on the iPlayer on the computer, you find yourself going,
0:25:10 > 0:25:12- "Oh, that was really funny," but I don't laugh.- Yeah.- Mmm-hmm.
0:25:12 > 0:25:14But if I'm with the other half at home,
0:25:14 > 0:25:18we just really fall about laughing, and it's a lovely...
0:25:18 > 0:25:21I don't know, it's a very comforting sound, hearing your partner laugh.
0:25:21 > 0:25:23OK, so we've put the theory to the test.
0:25:23 > 0:25:25We've isolated one of our audience members.
0:25:25 > 0:25:27Hello, Sherry.
0:25:27 > 0:25:30- Hi, Jimmy.- Hello.
0:25:30 > 0:25:32So, we've stuck you in isolation to watch the programme.
0:25:32 > 0:25:34- Are you enjoying it?- Yes.
0:25:35 > 0:25:37Good. LAUGHTER
0:25:37 > 0:25:39Well, it's been lovely chatting.
0:25:39 > 0:25:41So, you're on your own, watching the show.
0:25:41 > 0:25:43So we're going to have a look at your reaction
0:25:43 > 0:25:46to me telling jokes earlier, to see whether you laughed on your own.
0:25:46 > 0:25:48Let's have a look.
0:25:48 > 0:25:50..designing GM crops and cloning designer babies
0:25:50 > 0:25:52to investigate laughter.
0:25:53 > 0:25:55AUDIENCE LAUGHS
0:25:55 > 0:25:58..thermometer in her pocket and thinks...
0:25:58 > 0:26:00"some arsehole's got my pen."
0:26:02 > 0:26:04AUDIENCE LAUGHS
0:26:06 > 0:26:09So, Sherry, my question to you, why are you being a dick about it?
0:26:10 > 0:26:12I mean, it's a really good example, though,
0:26:12 > 0:26:15of you're watching the show and you seem pretty engaged, but...
0:26:15 > 0:26:17- You're not laughing. - I am laughing...inside.
0:26:19 > 0:26:20You're laughing on the inside?
0:26:21 > 0:26:25No, I mean that's... That's fair enough.
0:26:25 > 0:26:27And then we locked you in a room so you're...
0:26:27 > 0:26:30- You're not well pre-disposed to... - I just feel very much at home now,
0:26:30 > 0:26:33cos this is something that I do just at home by myself,
0:26:33 > 0:26:35watching you.
0:26:35 > 0:26:37LAUGHTER
0:26:40 > 0:26:42Well, you made this weird, Sherry.
0:26:43 > 0:26:46What I do on Snapchat is very much my own business.
0:26:47 > 0:26:50That's a... We'll get you to come into the studio
0:26:50 > 0:26:52for the rest of the show, because we've done this bit.
0:26:52 > 0:26:55But I think that really demonstrates that idea of the social activity,
0:26:55 > 0:26:57and I feel like, as my job being a stand-up,
0:26:57 > 0:27:01people come out to shows partly because they think the person
0:27:01 > 0:27:03onstage is funny, but partly because they want to laugh
0:27:03 > 0:27:05with their partner, with their friends.
0:27:05 > 0:27:08They sort of organically know that they enjoy that experience
0:27:08 > 0:27:10of being together with a room full of people
0:27:10 > 0:27:12that all have the same sense of humour as well.
0:27:12 > 0:27:14But what's kind of interesting, actually,
0:27:14 > 0:27:18if you looked round the room when you could hear laughter,
0:27:18 > 0:27:21it's not everybody that's laughing here.
0:27:21 > 0:27:23And in fact one of the weird things is,
0:27:23 > 0:27:26if you look at people in pubs laughing,
0:27:26 > 0:27:29you almost never get more than three people laughing together.
0:27:30 > 0:27:33But actually, if you think about it, that already makes laughter
0:27:33 > 0:27:35three times more efficient than grooming,
0:27:35 > 0:27:37for triggering the endorphin system,
0:27:37 > 0:27:41because when you groom, it's only the other person that gets the hit.
0:27:41 > 0:27:45When you laugh, you as the joke-teller, laugh as well.
0:27:45 > 0:27:47What you're saying there is when you tell a joke in a pub,
0:27:47 > 0:27:49- three people laugh.- No, two.
0:27:50 > 0:27:52- And you laugh, yeah. - I'm a pro, my friend.
0:27:52 > 0:27:54I can get the whole room.
0:27:54 > 0:27:56But most of the time, if you look,
0:27:56 > 0:27:58you've got...it's like a kind of Mexican wave effect.
0:27:58 > 0:28:00You've got little pockets laughing.
0:28:00 > 0:28:02It sounds like a lot of people laughing, but if you actually look,
0:28:02 > 0:28:04it's sort of going round in little waves.
0:28:04 > 0:28:06I often find that with certain types of jokes as well,
0:28:06 > 0:28:08- you sort of have a ripple effect of...- Yeah.
0:28:08 > 0:28:10..people are laughing and then they're laughing
0:28:10 > 0:28:13- at someone else laughing...- And also a good laugher to trigger it.
0:28:13 > 0:28:16If you've got a good laugher, who laughs at everything,
0:28:16 > 0:28:18it will trigger the waves of laughter round the room.
0:28:18 > 0:28:20Oh, I work with several professionals.
0:28:22 > 0:28:25So, laughter is a group activity but it's also linked to grooming
0:28:25 > 0:28:27in that it strengthens relationships.
0:28:27 > 0:28:30Couples that laugh together, stay together - certainly makes sense.
0:28:30 > 0:28:33There must be something that's stopping the Chuckle Brothers
0:28:33 > 0:28:35from killing each other. Take a look.
0:28:39 > 0:28:42At the University of North Carolina, it's graduation time.
0:28:44 > 0:28:47Students may be leaving, but for staff like Sara Algoe,
0:28:47 > 0:28:48the work goes on.
0:28:50 > 0:28:52I was really interested in laughter
0:28:52 > 0:28:55because it seems like the kind of behaviour that happens
0:28:55 > 0:28:58really frequently and is so relevant to the way
0:28:58 > 0:29:00that people think about
0:29:00 > 0:29:03their best relationships, and yet there is very little research on it.
0:29:07 > 0:29:10In another disproportionately ugly psychology department...
0:29:11 > 0:29:13..on an otherwise very pretty campus...
0:29:17 > 0:29:21..Sarah's PhD student Laura Kurtz is running an experiment
0:29:21 > 0:29:24to try to put some numbers on the idea that people who laugh together
0:29:24 > 0:29:25stay together.
0:29:28 > 0:29:30For this first interaction,
0:29:30 > 0:29:33we're interested in hearing about the first time you met.
0:29:33 > 0:29:35What was the first thing you said to me?
0:29:35 > 0:29:37"I'm going to marry you one day," and you said, "No".
0:29:37 > 0:29:41What I really love about this research is that it's so intuitive,
0:29:41 > 0:29:45so everyone can think of a time when they laughed with somebody.
0:29:45 > 0:29:48So you can think of probably a time in the past day or two,
0:29:48 > 0:29:51when you laughed with your friend or your romantic partner,
0:29:51 > 0:29:54but we can also think of a time when we laughed at something
0:29:54 > 0:29:57but the person next to us did not laugh,
0:29:57 > 0:29:59and suddenly in that moment...
0:30:00 > 0:30:02..what could have potentially been a really powerful thing,
0:30:02 > 0:30:05a powerful behaviour, all of a sudden takes a nosedive.
0:30:07 > 0:30:09After filling out a questionnaire that will tell the researchers
0:30:09 > 0:30:12how happy each of them is in their relationship,
0:30:12 > 0:30:15couples are recorded talking about the first time they met.
0:30:16 > 0:30:18- Yeah.- I thought that was really cute.
0:30:18 > 0:30:20It was cute. I was most probably lying about it, but...
0:30:22 > 0:30:25After the couples left the lab,
0:30:25 > 0:30:27we had a coder go back through all of those
0:30:27 > 0:30:28video-recorded interactions,
0:30:28 > 0:30:32coding for every start and stop time stamp of a laugh.
0:30:32 > 0:30:35- You were expecting me to be boring? - Well, you were a librarian.
0:30:35 > 0:30:37- You read my e-mails.- Yeah, but...
0:30:37 > 0:30:39Yeah, but it was still a librarian. I'm sorry!
0:30:39 > 0:30:41HE LAUGHS
0:30:41 > 0:30:44This is the way that we're able to quantify how much time
0:30:44 > 0:30:47they're spending actually laughing at exactly the same time,
0:30:47 > 0:30:49versus each person laughing separately.
0:30:51 > 0:30:52Oh, my gosh.
0:30:52 > 0:30:56So, what we found was that moments of shared laughter
0:30:56 > 0:30:59actually are predictive of greater closeness
0:30:59 > 0:31:02and feeling more supported by one's partner.
0:31:02 > 0:31:05So, those couples who laughed more tended to report more support
0:31:05 > 0:31:08and also generally feeling closer to their partner.
0:31:11 > 0:31:14- I had my eye on somebody else at that time.- Oh, really?- Yes, I did.
0:31:14 > 0:31:15Oh, I didn't know that.
0:31:15 > 0:31:17HE LAUGHS
0:31:17 > 0:31:19So, the message is pretty clear.
0:31:19 > 0:31:23Folklore has it that laughter may well ignite romantic attachment...
0:31:24 > 0:31:27..but science says, if you want to make it past infatuation...
0:31:27 > 0:31:29SHE GIGGLES ..and enjoy a long and happy
0:31:29 > 0:31:32relationship, you better carry on laughing.
0:31:38 > 0:31:40That was an interesting film.
0:31:40 > 0:31:42Finally, what every couple watching at home wants to see -
0:31:42 > 0:31:45a scientific way of determining exactly how doomed
0:31:45 > 0:31:47their relationship is.
0:31:47 > 0:31:49Well done, science.
0:31:49 > 0:31:51So, do couples that laugh together really stay together?
0:31:51 > 0:31:54One of the important things that kind of comes out of that, actually,
0:31:54 > 0:31:58I think, is that laughing together actually ramps up
0:31:58 > 0:32:01the endorphin production in the brain,
0:32:01 > 0:32:03it actually doubles it, in effect.
0:32:03 > 0:32:05We don't understand why, we have no idea why,
0:32:05 > 0:32:09but it's almost as though the system is designed to give you this
0:32:09 > 0:32:12- sort of real boost.- To encourage you to laugh with other people?
0:32:12 > 0:32:14- Yeah, yeah.- Yeah, buy two tickets.
0:32:15 > 0:32:17So, its sort of functionality is it releases endorphins
0:32:17 > 0:32:20and that feels good, but also it's a form of communication
0:32:20 > 0:32:22- in and of itself?- Yeah, and it lets you, together,
0:32:22 > 0:32:25regulate your emotions, cos it only works if both of you do it.
0:32:25 > 0:32:27If one person's going, "Ha-ha, it was funny,"
0:32:27 > 0:32:29and the other person's going, "No, it was quite a serious problem,"
0:32:29 > 0:32:32they're not... It's not going to work.
0:32:32 > 0:32:34So, there's two different types of laughter -
0:32:34 > 0:32:35there's laughter you do when you hear a joke
0:32:35 > 0:32:37and there's social laughter,
0:32:37 > 0:32:39laughter that peppers our communications.
0:32:39 > 0:32:41There's real laughter, at stuff we find funny,
0:32:41 > 0:32:45and there's posed laughter, which serves a vital social function.
0:32:45 > 0:32:47Sophie, you've done work on this, right?
0:32:47 > 0:32:49Yes, we've been looking at it in quite a lot of detail,
0:32:49 > 0:32:51because it does seem to be, essentially,
0:32:51 > 0:32:54two entirely different kinds of laughter that we use.
0:32:54 > 0:32:58Posed laughter - that sounds like... Is that someone going, "Ha-ha...ha"?
0:32:58 > 0:33:00- Well, it could be. It's... - LAUGHTER
0:33:00 > 0:33:03It sounds really bad, sort of...
0:33:03 > 0:33:06It was like you bounced it straight back.
0:33:06 > 0:33:08- SHE LAUGHS That was real.- Yeah.
0:33:09 > 0:33:12It sounds awful to say, "Who would want fake laughter?
0:33:12 > 0:33:15"I don't want you putting that on," but actually most of the laughter
0:33:15 > 0:33:18you encounter in conversations is so well-coordinated
0:33:18 > 0:33:21with the conversation that you're having,
0:33:21 > 0:33:24that it has to be part of your voluntary communication system.
0:33:24 > 0:33:27If you look at people laughing when they're having conversational...
0:33:27 > 0:33:30and they're talking to each other, they don't laugh randomly,
0:33:30 > 0:33:32they laugh at the ends of sentences, and then you start again
0:33:32 > 0:33:34and maybe somebody else picks up or you carry on.
0:33:34 > 0:33:38OK, well, shall we play in some real and some posed laughter
0:33:38 > 0:33:40and see if people can differentiate?
0:33:40 > 0:33:42OK, so... Well, take it away, Sophie.
0:33:42 > 0:33:45OK, we've got somebody laughing here. They may look familiar.
0:33:50 > 0:33:51OK, what do you think, audience?
0:33:51 > 0:33:53- AUDIENCE:- Real.- Real.
0:33:53 > 0:33:56Does everyone think it's real? Does anyone think it's posed?
0:33:56 > 0:33:57Posed.
0:33:57 > 0:33:59Who thinks it's posed?
0:33:59 > 0:34:03And you're saying that only a psychopath would do that, yeah?
0:34:03 > 0:34:05And they need to be institutionalised now.
0:34:05 > 0:34:09We'd need more than N=1 for data, but it's a worrying start.
0:34:09 > 0:34:12I'm fairly certain that one's real cos I start crying when I laugh.
0:34:15 > 0:34:18TYPEWRITER PINGS
0:34:18 > 0:34:21OK, let's have an old-style typewriter write it in green.
0:34:22 > 0:34:24If that doesn't say Horizon, I don't know what...
0:34:24 > 0:34:25That's science, my friend.
0:34:25 > 0:34:29That's a real laugh. See if we can try another one.
0:34:33 > 0:34:35OK, so real or posed?
0:34:35 > 0:34:38- AUDIENCE:- Posed.- Posed. - And does anyone think it's real?
0:34:38 > 0:34:40Genuinely, if anyone thought... It's fine.
0:34:44 > 0:34:46I can see maybe someone does and then they're going,
0:34:46 > 0:34:48"I'd better not say."
0:34:52 > 0:34:55Posed laughs, they've got their own thing going on.
0:34:55 > 0:34:57They're not just weak versions of real laughs.
0:34:57 > 0:35:01So, you quite often get nasality, a kind of heh-heh-heh quality
0:35:01 > 0:35:05to posed laughter that you never, ever find in spontaneous laughter,
0:35:05 > 0:35:07in fact, you couldn't do that when you were laughing helplessly.
0:35:07 > 0:35:10It's like we're marking it, we're showing it for what it is.
0:35:10 > 0:35:12I'm giving you my laughter. I'm voluntarily giving you
0:35:12 > 0:35:13this laughter.
0:35:13 > 0:35:15So we're going out of our way, possibly,
0:35:15 > 0:35:18to actually show people that this is a voluntary behaviour.
0:35:18 > 0:35:22OK, so we humans are not the only mammals that laugh.
0:35:22 > 0:35:25Now, can any other animal fake laugh?
0:35:25 > 0:35:28In chimpanzees, you do seem to find something that looks like
0:35:28 > 0:35:30a difference between a spontaneous laugh and a posed laugh.
0:35:30 > 0:35:34So, chimps laugh differently if they are being tickled
0:35:34 > 0:35:37than if they're trying to make play last longer, so that's...
0:35:37 > 0:35:40What if they're filming something for PG Tips?
0:35:40 > 0:35:42Cos often they've heard those jokes before.
0:35:42 > 0:35:43They're being polite.
0:35:43 > 0:35:47Yeah, so can we demonstrate that humans are the only ones
0:35:47 > 0:35:49that really know how to pose laughter?
0:35:49 > 0:35:50We're going to try this.
0:35:50 > 0:35:52I think we have a volunteer over there.
0:35:52 > 0:35:54Yes, you're our volunteer, come up.
0:35:54 > 0:35:55- What's your name, sir?- Phil.
0:35:55 > 0:35:57- Hello, Phil, how are you? - I'm good, thank you.
0:35:57 > 0:36:02I believe we need you to regress maybe ten million years, is it?
0:36:02 > 0:36:03How far are we going back?
0:36:03 > 0:36:06We're sending him back to walk on all fours.
0:36:06 > 0:36:10I'll cede knowledge here to Robin, but we need a quadruped.
0:36:10 > 0:36:11Just here is fine. I don't know if you...
0:36:11 > 0:36:13Yeah, go ahead, dude.
0:36:14 > 0:36:17- There we go.- Ah, you left your dignity at the table.
0:36:17 > 0:36:19LAUGHTER
0:36:19 > 0:36:22"Yeah, Mum, it's great news, I'm going to be on Horizon, but..."
0:36:23 > 0:36:26As soon as you start having to do this,
0:36:26 > 0:36:28you're having to use your four limbs, like all other mammals,
0:36:28 > 0:36:31to support your weight, and that means you can't use them
0:36:31 > 0:36:34for all that fine stuff we're doing when we're using our voice
0:36:34 > 0:36:37voluntarily - we're talking, we're doing social laughter.
0:36:37 > 0:36:40So, this is a slightly strange way of demonstrating
0:36:40 > 0:36:43how weirdly dependent we are on actually the fact that we're walking
0:36:43 > 0:36:45upright for a lot of the stuff we can do with our voices.
0:36:45 > 0:36:48So, could you fake a laugh now in that position, is that...?
0:36:48 > 0:36:50HE LAUGHS AND SPLUTTERS
0:36:50 > 0:36:51AUDIENCE LAUGH
0:36:51 > 0:36:53No, not really.
0:36:53 > 0:36:54I mean, definitively not.
0:36:54 > 0:36:57And we need him there for the rest of the show.
0:36:58 > 0:37:01It's a shame, really. He was probably quite enjoying it.
0:37:02 > 0:37:05See, now... So you're saying the reason we can fake laughter
0:37:05 > 0:37:07- is cos we're bipeds...- Bipeds, yeah.- ..and if we had to walk on
0:37:07 > 0:37:09all fours, as this man has to... LAUGHTER
0:37:11 > 0:37:14Contractually obliged to walk like this for the rest of the show.
0:37:14 > 0:37:15I mean...
0:37:15 > 0:37:18Probably a kinder sort of host would've got you to stand up
0:37:18 > 0:37:20by now, but...
0:37:20 > 0:37:22Go on, you'd better stand up. Our volunteer, everyone.
0:37:22 > 0:37:25Thank you very much. Great demonstration. It worked.
0:37:29 > 0:37:31So that kind of tightness in speech
0:37:31 > 0:37:34and the idea that you couldn't really sort of relax and pose
0:37:34 > 0:37:37and enjoy it as much if you're kind of, yeah.
0:37:37 > 0:37:39Absolutely. I mean, if you stress it even more, if you've got...
0:37:39 > 0:37:42you know, you try and take all your weight onto your arms,
0:37:42 > 0:37:45like doing pull-ups, then you just can't talk, you can't laugh,
0:37:45 > 0:37:46you can't do anything.
0:37:46 > 0:37:49So, I believe we have some brain scans of real and posed laughter.
0:37:49 > 0:37:52- We do.- Let's have a look at some brain scans, everyone.
0:37:53 > 0:37:56So, what we did here is we played people some sounds
0:37:56 > 0:37:58and buried in there we had real laughs and posed laughs.
0:37:58 > 0:38:01We didn't tell people anything about what they were going to hear,
0:38:01 > 0:38:03and we didn't tell them anything about laughter,
0:38:03 > 0:38:05and what we found is that the brain still cares.
0:38:05 > 0:38:08You get different patterns of activation when you hear real laughs
0:38:08 > 0:38:12versus posed laughs. So, for example, these regions here in blue,
0:38:12 > 0:38:15they're showing you areas of activation in the auditory cortices,
0:38:15 > 0:38:17just here above your ears,
0:38:17 > 0:38:19and that is greater for the real laughs
0:38:19 > 0:38:21than the posed laughs, significantly greater.
0:38:21 > 0:38:24And what that seems to be because is when you hear real laughter,
0:38:24 > 0:38:27you hear all these sounds you do not hear in any other context.
0:38:27 > 0:38:29It's completely sort of unambiguous.
0:38:29 > 0:38:33In contrast, we all see all these regions in pink,
0:38:33 > 0:38:36which are significantly more active to the posed laughter,
0:38:36 > 0:38:38and this is a bit surprising to us, cos we were expecting the brain
0:38:38 > 0:38:41to care very much about posed laughter as it's a bit, you know,
0:38:41 > 0:38:43it's not spontaneous, it's not real,
0:38:43 > 0:38:46but in fact it gives you more activation.
0:38:46 > 0:38:48And the activation it's giving you is not in auditory parts
0:38:48 > 0:38:51of the brain, it's in the parts of the brain you would expect to find
0:38:51 > 0:38:53if you were to sit down and deliberately think about
0:38:53 > 0:38:56what somebody else is thinking. So, I think what this speaks to
0:38:56 > 0:38:58is the fact that when you hear somebody producing
0:38:58 > 0:39:01a clearly posed laugh - a-ha-ha-ha -
0:39:01 > 0:39:04there is some reason why that human being has produced that behaviour
0:39:04 > 0:39:06and you are trying to work it out.
0:39:06 > 0:39:08Are they laughing cos they're in pain? Cos they're embarrassed?
0:39:08 > 0:39:11Cos they like you? Cos they want you to like them?
0:39:11 > 0:39:12There's a reason why they're doing it
0:39:12 > 0:39:14and that's why you're dwelling on it,
0:39:14 > 0:39:16even if you're having your brain scanned and it sounds like
0:39:16 > 0:39:18it's got nothing to do with you.
0:39:18 > 0:39:20It's such an important social signal.
0:39:20 > 0:39:22So, what happens if someone doesn't have the ability
0:39:22 > 0:39:23to tell the difference?
0:39:23 > 0:39:25Well, this is a very interesting question
0:39:25 > 0:39:27that we're trying to go into at the moment.
0:39:27 > 0:39:30So we've been doing some work, looking at how laughter is perceived
0:39:30 > 0:39:32by people with different kinds of problems.
0:39:32 > 0:39:35We've done some work in collaboration with colleagues at UCL
0:39:35 > 0:39:38looking at teenagers who have conduct disorders,
0:39:38 > 0:39:41and what you find is that, although the can behaviourally
0:39:41 > 0:39:44tell the difference between real and posed laughter,
0:39:44 > 0:39:46what they can't do, what they don't seem to do,
0:39:46 > 0:39:48is to show this contagion.
0:39:48 > 0:39:50They don't show this behavioural reaction,
0:39:50 > 0:39:52so they don't want to join in when they hear the laughter
0:39:52 > 0:39:55and their brains respond differently to the laughter.
0:39:55 > 0:39:58So there does seem to be something genuinely different happening
0:39:58 > 0:40:00when people process laughter
0:40:00 > 0:40:03who are at risk of having more serious problems,
0:40:03 > 0:40:05in terms of their social interactions.
0:40:05 > 0:40:06Wow, interesting.
0:40:06 > 0:40:09OK, so we've found out what laughter is
0:40:09 > 0:40:10and we know why we enjoy doing it.
0:40:10 > 0:40:14Final question - why do we laugh when we find things funny?
0:40:14 > 0:40:17Well, if only someone had a grand, unifying theory of comedy.
0:40:17 > 0:40:18Bit of luck - they do.
0:40:25 > 0:40:27Nestling beneath America's mighty Rocky Mountains
0:40:27 > 0:40:30is the University of Colorado at Boulder.
0:40:37 > 0:40:40One of its many architecturally unambitious buildings contains a man
0:40:40 > 0:40:44who claims to have discovered why we find things funny.
0:40:45 > 0:40:48His name is Professor Peter McGraw.
0:40:49 > 0:40:52We're at the University of Colorado, Boulder, at the lead school
0:40:52 > 0:40:55and we're headed to the human research lab
0:40:55 > 0:40:59which we affectionately refer to as HuRL.
0:40:59 > 0:41:02Unfortunately, even the science of humour
0:41:02 > 0:41:04has a kind of boring backdrop.
0:41:04 > 0:41:06I wish I could tell you that in a room over here
0:41:06 > 0:41:10we had a whole bunch of rubber chickens and whoopee cushions
0:41:10 > 0:41:12that we need to just pull out for our studies.
0:41:15 > 0:41:19Yet, despite, or maybe because of, this anodyne beige interior,
0:41:19 > 0:41:22it's here that Professor McGraw has devised
0:41:22 > 0:41:25his grand, unified theory of comedy.
0:41:25 > 0:41:29Humour deconstructed, laid bare and explained.
0:41:32 > 0:41:35So, most things in the world are OK.
0:41:36 > 0:41:37They're benign.
0:41:39 > 0:41:41They're not funny.
0:41:41 > 0:41:44And then, of course, there's a certain set of things in the world,
0:41:44 > 0:41:46you know, whether it be...
0:41:47 > 0:41:50..bad traffic or an annoying co-worker...
0:41:53 > 0:41:54..a tragedy...
0:41:56 > 0:41:57..that's a violation.
0:41:59 > 0:42:03This creates a boring reaction, this creates a negative reaction.
0:42:03 > 0:42:06But when you bring these two appraisals together
0:42:06 > 0:42:09and you create a benign violation,
0:42:09 > 0:42:14this sort of sweet spot that sits between being bored
0:42:14 > 0:42:16and being offended,
0:42:16 > 0:42:22and you have this moment of levity, this uplifting feeling of amusement,
0:42:22 > 0:42:23you say, "Hey, that's funny,"
0:42:23 > 0:42:25and then you laugh to communicate to others
0:42:25 > 0:42:28that this violation is actually benign.
0:42:33 > 0:42:35Word of the theory's power has spread.
0:42:37 > 0:42:40Local comedian Nathan Lund is keen to see
0:42:40 > 0:42:42if benign violation theory can rescue one of his jokes
0:42:42 > 0:42:45that even he thinks might be too offensive.
0:42:48 > 0:42:51- What's the joke? - Saying that I've been working on
0:42:51 > 0:42:54a type of clear mayonnaise
0:42:54 > 0:42:56called I Can't believe It's Not Cum, but...
0:42:56 > 0:42:58But that's...
0:42:58 > 0:43:01- That's kind of a violation... - That goes too far.
0:43:01 > 0:43:04- Yeah, that one goes too far, right? - It might.- I don't know yet.
0:43:04 > 0:43:05- People...- When it gets that "Uuggh."
0:43:05 > 0:43:09I also wonder if it's just too much, like, to go from,
0:43:09 > 0:43:12you know, clear mustard, that's pretty harmless,
0:43:12 > 0:43:14and then all of a sudden I'm bringing up...
0:43:14 > 0:43:15You know.
0:43:17 > 0:43:20After much debate, Professor McGraw and Nathan Lund come up with
0:43:20 > 0:43:23a solution they hope moves the joke away from violation
0:43:23 > 0:43:25just far enough to be funny.
0:43:30 > 0:43:31Happy to have him here.
0:43:31 > 0:43:33Please give a nice Boulder Comedy Show welcome
0:43:33 > 0:43:35to Nathan Lund, everybody.
0:43:37 > 0:43:40Now it's crunch time for clear mayonnaise,
0:43:40 > 0:43:43for Nathan and for benign violation theory.
0:43:43 > 0:43:46I don't have a lot of money, I'm hoping to make some money this year
0:43:46 > 0:43:48with a new product I have coming out.
0:43:48 > 0:43:50Clear mustard is what I've invented.
0:43:50 > 0:43:52I'm calling it Ham Sanitizer.
0:43:52 > 0:43:53LAUGHTER
0:43:53 > 0:43:58So, if you see Ham Sanitizer in stores, that's me, give it a shot.
0:44:00 > 0:44:04But I'm also working on a follow-up condiment - clear mayonnaise,
0:44:04 > 0:44:07which I'm calling I Can't believe It's Not Semen.
0:44:07 > 0:44:09- LAUGHTER - So, if you see...
0:44:09 > 0:44:14If you see that, that means people have been buying Ham Sanitizer,
0:44:14 > 0:44:18if I can follow it up with more clear condiments.
0:44:18 > 0:44:21So, do I have to explain all forms of comedy
0:44:21 > 0:44:23for this theory to be right?
0:44:23 > 0:44:24No.
0:44:24 > 0:44:27I just have to be able to explain comedy better
0:44:27 > 0:44:29than the other humour theories.
0:44:29 > 0:44:31And so, in many ways, it's kind of a horse race
0:44:31 > 0:44:33and I think I have a pretty fast horse.
0:44:33 > 0:44:36APPLAUSE
0:44:36 > 0:44:39Well, freshly arrived from Colorado in a matter transporter
0:44:39 > 0:44:42that we'll be looking at in next week's Horizon,
0:44:42 > 0:44:45ladies and gentlemen, please welcome Professor Peter McGraw.
0:44:45 > 0:44:47APPLAUSE
0:44:49 > 0:44:51Thank you for coming.
0:44:51 > 0:44:52Come in, take a seat.
0:44:52 > 0:44:54So, you think you have a pretty fast horse,
0:44:54 > 0:44:56you think your theory is pretty good on comedy.
0:44:56 > 0:45:01I mean, there's not a lot of good competition, so...
0:45:01 > 0:45:04Well, there's three main theories on comedy,
0:45:04 > 0:45:07- so let's go through those first. - Sure, sure.
0:45:07 > 0:45:11So, these are, these theories go back 2,500 years
0:45:11 > 0:45:12to Plato and Aristotle.
0:45:12 > 0:45:14So, Robin will remember some of them.
0:45:14 > 0:45:17LAUGHTER
0:45:17 > 0:45:19Go on. So, the first theory...
0:45:19 > 0:45:21..is superiority theory.
0:45:21 > 0:45:25And this is the notion that comedy is a game -
0:45:25 > 0:45:27there's a winner, there's a loser -
0:45:27 > 0:45:29and we laugh at other people's follies.
0:45:29 > 0:45:32- OK, excellent, so that's the first theory.- First theory.- Superiority.
0:45:32 > 0:45:35And then there's release theory or relief theory.
0:45:35 > 0:45:39Er, Freud gets a lot of the credit for this.
0:45:39 > 0:45:44And the notion is that we laugh at things that kind of release
0:45:44 > 0:45:47these sort of sexual and aggressive tendencies
0:45:47 > 0:45:48that we sort of hide away,
0:45:48 > 0:45:52that are part of our personality that are not supposed to come out,
0:45:52 > 0:45:56and so comedy is a safe way for these things to come out.
0:45:56 > 0:45:57OK, and the third theory?
0:45:57 > 0:45:59Is incongruity theory.
0:45:59 > 0:46:02- Which is the big...- It's the big one, it's the 800 pound gorilla.
0:46:02 > 0:46:05It's the one that people sort of spontaneously come up with
0:46:05 > 0:46:07when you ask them what makes things funny,
0:46:07 > 0:46:10and it takes various forms but the most common
0:46:10 > 0:46:13is sort of a mismatch of expectations and reality.
0:46:13 > 0:46:16So you expect one thing and you get something else,
0:46:16 > 0:46:18and that is supposed to be delighting.
0:46:18 > 0:46:20OK, so those are the three main theories in comedy,
0:46:20 > 0:46:22and had been for a very long time.
0:46:22 > 0:46:24- Yes.- No-one's really given it much thought beyond that.
0:46:24 > 0:46:27So your theory is, again, benign violation.
0:46:27 > 0:46:28That's right, yeah.
0:46:28 > 0:46:32So, the theory takes into account that many of the things
0:46:32 > 0:46:34that we laugh at kind of have a dark side,
0:46:34 > 0:46:37so that's acknowledged in superiority theory,
0:46:37 > 0:46:38it's acknowledged in relief theory.
0:46:38 > 0:46:42That is that there's something wrong, there's something amiss,
0:46:42 > 0:46:44there's something threatening about that situation.
0:46:44 > 0:46:47But of course the things that are wrong or amiss and threatening,
0:46:47 > 0:46:49they don't make us laugh, they make us cry,
0:46:49 > 0:46:52they disgust us, they offend us.
0:46:52 > 0:46:55And so you have this negative arousal
0:46:55 > 0:46:57that comes from that dark side,
0:46:57 > 0:47:00and then it flips and then you delight
0:47:00 > 0:47:03and you have this positively arousing feeling, and then...
0:47:03 > 0:47:07I like to believe that laughter is that signal that this situation
0:47:07 > 0:47:09that seems wrong is actually OK.
0:47:09 > 0:47:11I mean, the thing I love about your theory
0:47:11 > 0:47:14is the idea that everyone has a different Venn diagram.
0:47:14 > 0:47:16- Yes.- Everyone's drawn it very differently.
0:47:16 > 0:47:17So something that I might find...
0:47:17 > 0:47:19I might say, "Well, that isn't a violation to me,
0:47:19 > 0:47:21"I'm happy to laugh about that,"
0:47:21 > 0:47:23someone else might go, "Not on the BBC, thank you."
0:47:23 > 0:47:26And someone else might go, "You gotta give me more."
0:47:26 > 0:47:29The things that are wrong, and the things that are OK in the world
0:47:29 > 0:47:31change over time.
0:47:31 > 0:47:34So you listen back to old comedy
0:47:34 > 0:47:38and sometimes it's horribly offensive and bigoted now,
0:47:38 > 0:47:39from our perspective,
0:47:39 > 0:47:42and sometimes it's totally boring and confusing,
0:47:42 > 0:47:44and it's because the world has changed.
0:47:44 > 0:47:47And so, in many ways,
0:47:47 > 0:47:52good comedy really reflects the values of a society
0:47:52 > 0:47:55and the moral norms and the beliefs in a society,
0:47:55 > 0:47:57and those are constantly in flux.
0:47:57 > 0:47:59So, it's not just the individuals that move
0:47:59 > 0:48:01those kind of Venn diagrams of, you know, where that line is,
0:48:01 > 0:48:03it's a society as a whole that moves them
0:48:03 > 0:48:06and different nations have them in different places as well, yeah.
0:48:06 > 0:48:08Yes. Every so often you find something that lasts.
0:48:08 > 0:48:10I mean, it still won't last forever,
0:48:10 > 0:48:14but my son is very keen on listening to
0:48:14 > 0:48:16very old Tony Hancock radio programmes,
0:48:16 > 0:48:18and it's surprising how much of that has lasted,
0:48:18 > 0:48:21probably because it was hugely influential.
0:48:21 > 0:48:24It was basically you could draw a line straight from that to Seinfeld,
0:48:24 > 0:48:27and it's quite interesting how every so often you run across something
0:48:27 > 0:48:29that's almost jarringly out of place.
0:48:29 > 0:48:31It's very interesting, from my perspective,
0:48:31 > 0:48:32the kind of comedy that I do,
0:48:32 > 0:48:36the idea that no-one's ever laughed at an offensive joke,
0:48:36 > 0:48:39because, by dint of laughing, they're saying that,
0:48:39 > 0:48:41"No, this isn't a violation to me, this is all fine."
0:48:41 > 0:48:43- Mm-hmm.- We can laugh about anything.
0:48:43 > 0:48:45It's not that it's completely fine, right?
0:48:45 > 0:48:49That's the thing that's so difficult about it all.
0:48:49 > 0:48:51The things that are completely fine
0:48:51 > 0:48:55is like you listening to me, not very funny.
0:48:55 > 0:48:59Right? And so, there has to be something edgy that plays that role.
0:48:59 > 0:49:02- This guy.- This guy right here. - I think... I really like the theory.
0:49:02 > 0:49:04I mean, I really feel like it makes sense to me
0:49:04 > 0:49:05in a way that the others don't.
0:49:05 > 0:49:09But I'd be very interested to know what Sophie and Robin make of this.
0:49:09 > 0:49:10No pressure.
0:49:10 > 0:49:13Well, I was going to say, actually, this is kind of interesting because,
0:49:13 > 0:49:17if you look at the origins of laughter as we have it in humans,
0:49:17 > 0:49:20it actually comes from the play vocalisation in monkeys and apes,
0:49:20 > 0:49:26and what that basically is is a comment on what I'm doing now.
0:49:26 > 0:49:28When I bite you, don't take it seriously.
0:49:28 > 0:49:30So, it's doing exactly this,
0:49:30 > 0:49:33it's just saying, "Look, it may look aggressive, but actually it's not."
0:49:33 > 0:49:36And I think it's... The thing I find interesting,
0:49:36 > 0:49:37and you mentioned it in the film,
0:49:37 > 0:49:40is that people are kind of appraising the situation,
0:49:40 > 0:49:42they're coming to a decision about it.
0:49:42 > 0:49:44And there is some very interesting data
0:49:44 > 0:49:47showing that people will rate jokes as being funnier
0:49:47 > 0:49:49if they think they've been told by a comedian
0:49:49 > 0:49:53than if they think they've been told by somebody who's famous but not...
0:49:53 > 0:49:54does not have that role.
0:49:54 > 0:49:57So, if somebody thinks a joke's been told by Jimmy Carr,
0:49:57 > 0:49:59they'll rate it as more amusing
0:49:59 > 0:50:01than if they think it's been told by Jamie Oliver,
0:50:01 > 0:50:04and that does suggest that people aren't just...
0:50:04 > 0:50:08Their appraisal is including the person who is producing it.
0:50:08 > 0:50:11And I think that kind of might speak in, socially,
0:50:11 > 0:50:14to the kind of the people who you will and won't let make you laugh.
0:50:14 > 0:50:17You know, you are going to laugh more with people you know and like,
0:50:17 > 0:50:20and you may read their intentions as being more benign.
0:50:20 > 0:50:22I think that's very true of political correctness as well,
0:50:22 > 0:50:26cos I often get called out for saying, "Oh, you're not very politically correct,"
0:50:26 > 0:50:27but I always think I am within context.
0:50:27 > 0:50:30Onstage, in front of 1,000 people, telling jokes,
0:50:30 > 0:50:32political correctness doesn't really belong in that space for me.
0:50:32 > 0:50:35So, as soon as whenever you get called out by the press
0:50:35 > 0:50:37as a comedian and they say, "Ban this filth,"
0:50:37 > 0:50:39it tends to be that they've taken it from a comedy show,
0:50:39 > 0:50:41put it on the front of the Daily Mail
0:50:41 > 0:50:42and gone, "This is disgraceful!"
0:50:42 > 0:50:45Well, you shouldn't have printed it, then.
0:50:45 > 0:50:47OK, how about some good news?
0:50:47 > 0:50:48Take a look.
0:50:54 > 0:50:56When this man started his career,
0:50:56 > 0:50:58his ideas were considered
0:50:58 > 0:51:01even more avant-garde than the buildings he now inhabits.
0:51:03 > 0:51:06Today, however, he's established a global reputation
0:51:06 > 0:51:09as one of the world's leading neurobiologists.
0:51:14 > 0:51:19And all because he discovered he could hear rats squeak.
0:51:19 > 0:51:21RATS SQUEAK
0:51:26 > 0:51:30You're hearing the squeaking through the ultrasound detector.
0:51:30 > 0:51:32If we didn't have these detectors on,
0:51:32 > 0:51:34you would not be hearing anything.
0:51:35 > 0:51:37Once he'd heard the squeaks,
0:51:37 > 0:51:41Panksepp was determined to discover what they might mean.
0:51:42 > 0:51:44One morning I woke up and said,
0:51:44 > 0:51:46"What if that is laughter?
0:51:46 > 0:51:50And I said, "Well, then you should be able to tickle animals."
0:51:50 > 0:51:55And we tickled the first rat, and it chirped like crazy.
0:51:55 > 0:51:56The second rat...
0:51:56 > 0:51:57As a matter of fact,
0:51:57 > 0:52:03every rat except some really neurotic ones have chirped.
0:52:08 > 0:52:09To the casual observer,
0:52:09 > 0:52:12it might look like the rats aren't laughing at all,
0:52:12 > 0:52:14that their tiny chirps are in fact cries for help.
0:52:18 > 0:52:21But not only are the vocalisations identical
0:52:21 > 0:52:23to the noises made in play,
0:52:23 > 0:52:25the rats' behaviour tells its own story.
0:52:28 > 0:52:30They are following my hand
0:52:30 > 0:52:33because it's a hand that has brought them great joy.
0:52:33 > 0:52:35HE CHUCKLES
0:52:35 > 0:52:37Oh, he just bit me.
0:52:37 > 0:52:40- HE LAUGHS - But he didn't hurt me.
0:52:40 > 0:52:44So that's their way of indicating, "Come on, let's play." Ooh!
0:52:44 > 0:52:46- I love rats. - HE LAUGHS
0:52:46 > 0:52:51They're such fun animals, so smart and so emotional.
0:52:52 > 0:52:57As far as we can tell, we've got the same basic emotions as rats.
0:53:01 > 0:53:04But Panksepp's idea, that rats have emotions,
0:53:04 > 0:53:07did little to endear him to his colleagues.
0:53:08 > 0:53:11People say you've been giving human qualities to animals -
0:53:11 > 0:53:12anthropomorphism -
0:53:12 > 0:53:16and I tell them I have not been doing anything of the sort.
0:53:16 > 0:53:18I am doing zoomorphism.
0:53:18 > 0:53:21I am trying to understand the animal mind
0:53:21 > 0:53:25as a way to illuminate the human mind.
0:53:27 > 0:53:30The critics argue that our complex brains are so different
0:53:30 > 0:53:33to rats' brains that any comparison is meaningless.
0:53:34 > 0:53:40But the reality is emotions occur in the evolutionary ancient brain,
0:53:40 > 0:53:43the part we share with all mammals, including rats.
0:53:44 > 0:53:48And we know that animals that have been bred for high laughter
0:53:48 > 0:53:50are resistant to depression.
0:53:50 > 0:53:53That means they have chemistries that protect them
0:53:53 > 0:53:56against the vicissitudes of life.
0:53:57 > 0:54:00Animals that have been bred for lower laughter
0:54:00 > 0:54:02are susceptible to depression.
0:54:05 > 0:54:08If we understand animal emotional processes
0:54:08 > 0:54:11at the fundamental instinctual level,
0:54:11 > 0:54:15I think we will have a science of human basic emotions,
0:54:15 > 0:54:19and that's very valuable for understanding ourselves
0:54:19 > 0:54:22and having a more sophisticated biological psychiatry.
0:54:24 > 0:54:27Panksepp's idea was to use the rats' laughter to identify
0:54:27 > 0:54:31the precise area in the ancient brain involved in happiness,
0:54:31 > 0:54:35and in so doing to identify the neurochemistry responsible.
0:54:37 > 0:54:40Using that approach, a group from Northwestern University in Chicago
0:54:40 > 0:54:43identified a happiness neurotransmitter.
0:54:43 > 0:54:45They call it GLX-13.
0:54:45 > 0:54:47Catchy.
0:54:47 > 0:54:50And they've also developed a drug to stimulate its production.
0:54:50 > 0:54:54In 2013, they started human clinical trials.
0:54:54 > 0:54:56The results were so impressive,
0:54:56 > 0:55:02that two years later it was bought by a drugs company for 560 million.
0:55:03 > 0:55:05Surprising as it is,
0:55:05 > 0:55:09£560 million is not bad for buying the rights
0:55:09 > 0:55:12to the most powerful item on the horizon.
0:55:16 > 0:55:18It's a new way of treating depression -
0:55:18 > 0:55:21an antidepressant that, instead of reducing sadness,
0:55:21 > 0:55:23promotes happiness.
0:55:23 > 0:55:26It's an approach that shows great promise,
0:55:26 > 0:55:28and all this from tickling rats.
0:55:30 > 0:55:35Rat laughter forces you to think about the molecules of social joy,
0:55:35 > 0:55:42so, you know, I am pleased and surprised in retrospect
0:55:42 > 0:55:45that we got that far.
0:55:45 > 0:55:49And, you know, it's one of the wonderful things of science -
0:55:49 > 0:55:51there's always surprises.
0:55:57 > 0:55:59So, that's me out of a job.
0:55:59 > 0:56:01Comedy in pill form - I suppose it had to happen sometime.
0:56:01 > 0:56:03We had a good run. LAUGHTER
0:56:03 > 0:56:05So, back to our questions - what is laughter?
0:56:05 > 0:56:08Why do we laugh? And what has it got to do with comedy?
0:56:08 > 0:56:10- I think we've answered it, haven't we?- Yeah.
0:56:10 > 0:56:11Laughter's a social emotion.
0:56:11 > 0:56:13Social activity,
0:56:13 > 0:56:16pre-language vocalisation.
0:56:16 > 0:56:18OK. Why do we laugh?
0:56:18 > 0:56:23Originally it really is designed to allow us to bond with each other,
0:56:23 > 0:56:25but actually the endorphins that trigger out
0:56:25 > 0:56:27in effect tune the immune system.
0:56:27 > 0:56:29So they actually do make you healthier.
0:56:29 > 0:56:31But it's very ancient, it is,
0:56:31 > 0:56:32I mean, it predates language
0:56:32 > 0:56:35probably by about a million and a half years, I would say.
0:56:35 > 0:56:38Wow. OK. And what's it got to do with comedy?
0:56:38 > 0:56:40Well, comedy fundamentally is about pointing out
0:56:40 > 0:56:42what's wrong with the world
0:56:42 > 0:56:44and doing it in a way that is acceptable to the audience,
0:56:44 > 0:56:48so creating benign violations and delighting others.
0:56:48 > 0:56:51Here's a question for all three of you.
0:56:51 > 0:56:55Could it be said that laughter makes us human?
0:56:55 > 0:56:56No.
0:56:56 > 0:56:58- I would say so.- I don't think so.
0:56:58 > 0:57:01- It's just too... - OK, so Robin's my favourite.
0:57:01 > 0:57:03- LAUGHTER - I get the free tickets to his shows.
0:57:03 > 0:57:05I'd like to thank Robin and the other two guests... Meh.
0:57:05 > 0:57:07So, you think it...?
0:57:07 > 0:57:12Well, in the sense that it does mark a key boundary point
0:57:12 > 0:57:15from which everything else spins.
0:57:15 > 0:57:19And of course the big thing about laughter is this breath control
0:57:19 > 0:57:22and all this sort of control of the musculature,
0:57:22 > 0:57:24the intercostal muscles in the chest wall,
0:57:24 > 0:57:27and without that, language couldn't have evolved.
0:57:27 > 0:57:30I mean, we've literally nailed this episode of Horizon.
0:57:30 > 0:57:32LAUGHTER I'd like to thank our guests -
0:57:32 > 0:57:34Sophie Scott, Robin Dunbar and Peter McGraw,
0:57:34 > 0:57:36and thank you all for laughing.
0:57:36 > 0:57:38APPLAUSE