[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:12.99,0:00:15.24,Default,,0000,0000,0000,,... just as everyone goes,\N'Great, quick nap.'
Dialogue: 0,0:00:15.88,0:00:17.13,Default,,0000,0000,0000,,Don't have a nap!
Dialogue: 0,0:00:17.73,0:00:20.93,Default,,0000,0000,0000,,Raise your hand - just squeeze\Nyour left ear as hard as you can.
Dialogue: 0,0:00:21.43,0:00:23.01,Default,,0000,0000,0000,,Raise your hand if it hurt.
Dialogue: 0,0:00:23.24,0:00:25.04,Default,,0000,0000,0000,,Fantastic. Thanks for having me.
Dialogue: 0,0:00:25.04,0:00:26.04,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:00:26.04,0:00:27.48,Default,,0000,0000,0000,,No, no - it's not true.
Dialogue: 0,0:00:27.48,0:00:28.77,Default,,0000,0000,0000,,Let me tell you a story.
Dialogue: 0,0:00:28.77,0:00:31.35,Default,,0000,0000,0000,,I just want to take that\Noff the screen for the moment.
Dialogue: 0,0:00:31.35,0:00:33.74,Default,,0000,0000,0000,,I want to tell you a story\Nthat will explain to you
Dialogue: 0,0:00:33.74,0:00:36.03,Default,,0000,0000,0000,,the first three years\Nof the Neurobiology of Pain
Dialogue: 0,0:00:36.03,0:00:38.24,Default,,0000,0000,0000,,that you would study\Nat university.
Dialogue: 0,0:00:38.49,0:00:40.74,Default,,0000,0000,0000,,Eight years ago, \NI was walking in the bush.
Dialogue: 0,0:00:41.14,0:00:42.62,Default,,0000,0000,0000,,I had a sarong on.
Dialogue: 0,0:00:43.05,0:00:44.12,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:00:45.52,0:00:47.64,Default,,0000,0000,0000,,Very cool. This is what happened.
Dialogue: 0,0:00:50.65,0:00:52.03,Default,,0000,0000,0000,,Did you see that?
Dialogue: 0,0:00:52.38,0:00:54.41,Default,,0000,0000,0000,,Hang on, this is what happened.
Dialogue: 0,0:00:57.13,0:01:00.14,Default,,0000,0000,0000,,Biologically, I'm going to tell you \Nwhat happened just then.
Dialogue: 0,0:01:00.14,0:01:03.01,Default,,0000,0000,0000,,Something touched the outside \Nof my left leg in the skin.
Dialogue: 0,0:01:03.65,0:01:05.05,Default,,0000,0000,0000,,That activates receptors
Dialogue: 0,0:01:05.05,0:01:08.24,Default,,0000,0000,0000,,on the end of big fat, myelinated,\Nfast-conducting nerve fibres,
Dialogue: 0,0:01:08.57,0:01:10.63,Default,,0000,0000,0000,,and they stream\Nstraight up my leg - whizz -
Dialogue: 0,0:01:10.63,0:01:13.87,Default,,0000,0000,0000,,straight into my spinal cord - \Nwhizz - up to this part of my brain,
Dialogue: 0,0:01:13.87,0:01:14.88,Default,,0000,0000,0000,,and they say,
Dialogue: 0,0:01:14.88,0:01:18.30,Default,,0000,0000,0000,,'You've just been touched on the outside\Nof your left leg in the skin.'
Dialogue: 0,0:01:18.30,0:01:20.29,Default,,0000,0000,0000,,(Panting) (Laughter)
Dialogue: 0,0:01:20.29,0:01:22.48,Default,,0000,0000,0000,,Meanwhile, whatever it was
Dialogue: 0,0:01:22.93,0:01:26.14,Default,,0000,0000,0000,,is sufficiently intense\Nto activate free nerve endings;
Dialogue: 0,0:01:26.14,0:01:28.07,Default,,0000,0000,0000,,we call them 'nociceptors'.
Dialogue: 0,0:01:28.07,0:01:32.36,Default,,0000,0000,0000,,They're thin, unmyelinated, \Nslow-conducting Lada Niva -
Dialogue: 0,0:01:33.96,0:01:35.66,Default,,0000,0000,0000,,someone knows\Nwhat a Lada Niva is -
Dialogue: 0,0:01:35.66,0:01:36.65,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:01:36.65,0:01:37.66,Default,,0000,0000,0000,,nerve fibres.
Dialogue: 0,0:01:37.66,0:01:40.52,Default,,0000,0000,0000,,And that message travels\Nup to my spinal cord,
Dialogue: 0,0:01:40.52,0:01:42.44,Default,,0000,0000,0000,,and that's as far as it goes.
Dialogue: 0,0:01:42.44,0:01:46.25,Default,,0000,0000,0000,,And it says to a fresh neuron\Nin my spinal cord,
Dialogue: 0,0:01:46.81,0:01:51.88,Default,,0000,0000,0000,,'Something dangerous has happened on\Nthe outside of your left leg in the skin,
Dialogue: 0,0:01:53.40,0:01:54.47,Default,,0000,0000,0000,,mate.'
Dialogue: 0,0:01:54.48,0:01:55.66,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:01:55.66,0:01:58.96,Default,,0000,0000,0000,,And the spinal nociceptor\Ntakes that message up to the thalamus,
Dialogue: 0,0:01:58.96,0:02:00.40,Default,,0000,0000,0000,,which sits in there somewhere,
Dialogue: 0,0:02:00.40,0:02:05.41,Default,,0000,0000,0000,,and says, 'There's danger on the outside\Nof your left leg in the skin, mate.'
Dialogue: 0,0:02:06.43,0:02:09.51,Default,,0000,0000,0000,,Now the brain has to evaluate \Nhow dangerous this really is.
Dialogue: 0,0:02:09.82,0:02:11.37,Default,,0000,0000,0000,,So it looks at everything.
Dialogue: 0,0:02:11.66,0:02:14.73,Default,,0000,0000,0000,,And the way that I make sense of this,\Nof what happened to me,
Dialogue: 0,0:02:14.73,0:02:18.74,Default,,0000,0000,0000,,is the brain thought, 'Frontal lobe,\Nhave we been anywhere like this before?'
Dialogue: 0,0:02:18.74,0:02:21.80,Default,,0000,0000,0000,,Hang on, I'll just ask \Nthe posterior parietal cortex.
Dialogue: 0,0:02:22.49,0:02:24.50,Default,,0000,0000,0000,,Have we been in this environment before?
Dialogue: 0,0:02:24.50,0:02:25.55,Default,,0000,0000,0000,,Yes, we have.
Dialogue: 0,0:02:26.07,0:02:28.50,Default,,0000,0000,0000,,Has it happened at this stage\Nof the gait cycle?
Dialogue: 0,0:02:28.50,0:02:29.70,Default,,0000,0000,0000,,Yes it has.
Dialogue: 0,0:02:29.93,0:02:31.65,Default,,0000,0000,0000,,Is it coming from the same location?
Dialogue: 0,0:02:31.65,0:02:33.09,Default,,0000,0000,0000,,Yes it is.\NWhat is it?
Dialogue: 0,0:02:33.30,0:02:37.22,Default,,0000,0000,0000,,Well your whole life growing up, \Nyou used to scratch your legs on twigs.
Dialogue: 0,0:02:37.86,0:02:39.51,Default,,0000,0000,0000,,This is not dangerous.
Dialogue: 0,0:02:40.23,0:02:42.71,Default,,0000,0000,0000,,I'm going to give you,\Nthe organism, something
Dialogue: 0,0:02:42.71,0:02:45.90,Default,,0000,0000,0000,,so you can kick off the twig\Nand continue on your merry way.
Dialogue: 0,0:02:46.25,0:02:48.02,Default,,0000,0000,0000,,And that's what happened for me.
Dialogue: 0,0:02:48.40,0:02:50.75,Default,,0000,0000,0000,,I can't show you now, \Nbut I took off my sarong,
Dialogue: 0,0:02:51.14,0:02:53.35,Default,,0000,0000,0000,,got in the river, got out of the river,
Dialogue: 0,0:02:53.35,0:02:55.47,Default,,0000,0000,0000,,and that's the last thing I remember,
Dialogue: 0,0:02:55.82,0:02:58.11,Default,,0000,0000,0000,,having been bitten\Nby an eastern brown snake.
Dialogue: 0,0:02:58.11,0:02:59.40,Default,,0000,0000,0000,,(Mumbling)
Dialogue: 0,0:02:59.52,0:03:00.62,Default,,0000,0000,0000,,Survivor.
Dialogue: 0,0:03:00.62,0:03:01.86,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:03:02.22,0:03:03.87,Default,,0000,0000,0000,,Thank you very much.
Dialogue: 0,0:03:03.87,0:03:05.16,Default,,0000,0000,0000,,(Applause)
Dialogue: 0,0:03:05.36,0:03:06.40,Default,,0000,0000,0000,,Now, for some reason,
Dialogue: 0,0:03:06.40,0:03:10.01,Default,,0000,0000,0000,,the eastern brown snake\Nworks by poisoning you - clearly -
Dialogue: 0,0:03:10.39,0:03:12.96,Default,,0000,0000,0000,,and one of the things it does is\Nactivate nerve fibres.
Dialogue: 0,0:03:12.96,0:03:15.30,Default,,0000,0000,0000,,So actually my brain\Nwould have got these messages
Dialogue: 0,0:03:15.30,0:03:17.64,Default,,0000,0000,0000,,saying, Danger! Danger! Danger! Danger!
Dialogue: 0,0:03:17.64,0:03:20.84,Default,,0000,0000,0000,,and, in its wisdom, it said, No. No. No.
Dialogue: 0,0:03:21.93,0:03:26.83,Default,,0000,0000,0000,,Six months later, I'm walking\Nin the bush with a boring talker.
Dialogue: 0,0:03:27.43,0:03:29.01,Default,,0000,0000,0000,,You know what a boring talker is?
Dialogue: 0,0:03:29.01,0:03:31.77,Default,,0000,0000,0000,,Those people, it doesn't matter\Nwhat they say, it's boring.
Dialogue: 0,0:03:31.77,0:03:32.77,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:03:32.77,0:03:36.74,Default,,0000,0000,0000,,It's irrelevant, but we'll call her Naomi
Dialogue: 0,0:03:38.27,0:03:40.07,Default,,0000,0000,0000,,because that is her name.
Dialogue: 0,0:03:40.07,0:03:41.34,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:03:41.70,0:03:43.67,Default,,0000,0000,0000,,Anyway, this is what happened, right?
Dialogue: 0,0:03:45.40,0:03:46.56,Default,,0000,0000,0000,,Ow! Wah!
Dialogue: 0,0:03:46.73,0:03:47.95,Default,,0000,0000,0000,,And I'm in agony.
Dialogue: 0,0:03:47.95,0:03:51.47,Default,,0000,0000,0000,,I have got a white-hot poke of pain\Nscreaming up my leg.
Dialogue: 0,0:03:52.39,0:03:54.77,Default,,0000,0000,0000,,I'll tell you, biologically,\Nwhat's happened.
Dialogue: 0,0:03:54.77,0:03:57.49,Default,,0000,0000,0000,,Something touched the outside \Nof my left leg in the skin.\N
Dialogue: 0,0:03:57.49,0:04:00.02,Default,,0000,0000,0000,,That activates big, fat, \Nmyelinated nerve fibres
Dialogue: 0,0:04:00.02,0:04:02.42,Default,,0000,0000,0000,,which send a message -\Nwhizz - whizz - up to here.
Dialogue: 0,0:04:02.42,0:04:05.42,Default,,0000,0000,0000,,Just been touched on the outside \Nof your left leg in the skin.
Dialogue: 0,0:04:05.76,0:04:08.75,Default,,0000,0000,0000,,It's sufficiently intense to activate\Nthese free nerve endings.
Dialogue: 0,0:04:08.75,0:04:11.92,Default,,0000,0000,0000,,Danger receptors take\Nthe message to my spinal cord:
Dialogue: 0,0:04:11.92,0:04:15.87,Default,,0000,0000,0000,,something dangerous has happened on\Nthe outside of your left leg in the skin.
Dialogue: 0,0:04:15.87,0:04:16.87,Default,,0000,0000,0000,,(Audience) Mate.
Dialogue: 0,0:04:16.87,0:04:18.08,Default,,0000,0000,0000,,Yes!
Dialogue: 0,0:04:18.08,0:04:19.46,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:04:19.84,0:04:21.56,Default,,0000,0000,0000,,Well done, you weren't planted.
Dialogue: 0,0:04:22.18,0:04:24.58,Default,,0000,0000,0000,,That goes to the thalamus\Nand says the same thing:
Dialogue: 0,0:04:24.59,0:04:26.37,Default,,0000,0000,0000,,something dangerous has just happened
Dialogue: 0,0:04:26.37,0:04:28.44,Default,,0000,0000,0000,,on the outside\Nof your left leg in the skin.
Dialogue: 0,0:04:28.44,0:04:29.54,Default,,0000,0000,0000,,(Audience) Mate!
Dialogue: 0,0:04:29.54,0:04:33.29,Default,,0000,0000,0000,,So the brain says, thanks very much, \NThalamus, kids alright? Good, anyway ...
Dialogue: 0,0:04:33.29,0:04:34.34,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:04:34.34,0:04:36.54,Default,,0000,0000,0000,,Frontal cortex,\Nanything to tell me about this?
Dialogue: 0,0:04:36.54,0:04:39.74,Default,,0000,0000,0000,,Hang on, I'll ask the posterior \Nparietal cortex: where are we?
Dialogue: 0,0:04:39.75,0:04:41.33,Default,,0000,0000,0000,,We're walking in the bush.
Dialogue: 0,0:04:44.93,0:04:46.98,Default,,0000,0000,0000,,You're a bit 'mate' happy.
Dialogue: 0,0:04:48.10,0:04:49.64,Default,,0000,0000,0000,,At this stage of the gait cycle?
Dialogue: 0,0:04:49.64,0:04:51.95,Default,,0000,0000,0000,,Where's it coming from?\NHave we been here before?
Dialogue: 0,0:04:51.95,0:04:53.41,Default,,0000,0000,0000,,Oh yes, we have.
Dialogue: 0,0:04:53.81,0:04:55.93,Default,,0000,0000,0000,,Last time we were here, you almost died.
Dialogue: 0,0:04:56.68,0:04:59.86,Default,,0000,0000,0000,,I'm going to make this hurt so much \Nthat you can do nothing else.
Dialogue: 0,0:04:59.86,0:05:03.36,Default,,0000,0000,0000,,And I was in absolute agony \Nfor what seemed like minutes.
Dialogue: 0,0:05:03.70,0:05:05.18,Default,,0000,0000,0000,,Screaming pain -
Dialogue: 0,0:05:06.18,0:05:10.16,Default,,0000,0000,0000,,until one of my mates looked at my leg,\Nand there's a little scratch from a twig.
Dialogue: 0,0:05:10.16,0:05:11.65,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:05:12.28,0:05:14.78,Default,,0000,0000,0000,,The pain in those situations \Nwas totally different
Dialogue: 0,0:05:15.46,0:05:16.80,Default,,0000,0000,0000,,because of meaning.
Dialogue: 0,0:05:17.47,0:05:20.53,Default,,0000,0000,0000,,I want to convince you that pain\Nis an illusion 100% of the time.
Dialogue: 0,0:05:20.53,0:05:22.18,Default,,0000,0000,0000,,Here's a visual illusion ...
Dialogue: 0,0:05:22.36,0:05:23.87,Default,,0000,0000,0000,,So have a look at this picture,
Dialogue: 0,0:05:23.87,0:05:26.96,Default,,0000,0000,0000,,you've got a square that's got A in it\Nand one that's got B in it.
Dialogue: 0,0:05:27.44,0:05:30.39,Default,,0000,0000,0000,,Raise your hand if you think \Nthat the square with A in it
Dialogue: 0,0:05:30.39,0:05:33.25,Default,,0000,0000,0000,,looks darker than the square with B in it.
Dialogue: 0,0:05:34.35,0:05:35.74,Default,,0000,0000,0000,,Thank goodness for that.
Dialogue: 0,0:05:35.74,0:05:40.18,Default,,0000,0000,0000,,None of you have a really socially\Nembarrassing neurological disorder.
Dialogue: 0,0:05:40.50,0:05:41.69,Default,,0000,0000,0000,,Except you.
Dialogue: 0,0:05:41.69,0:05:42.76,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:05:42.76,0:05:43.96,Default,,0000,0000,0000,,That's not true.
Dialogue: 0,0:05:44.76,0:05:47.19,Default,,0000,0000,0000,,Watch what happens \Nif we have another look at this.
Dialogue: 0,0:05:47.19,0:05:50.23,Default,,0000,0000,0000,,These are those two squares\Ntaken out of that picture.
Dialogue: 0,0:05:50.83,0:05:54.62,Default,,0000,0000,0000,,Hopefully you can see they're identical,\Nand some of you may not believe me.
Dialogue: 0,0:05:54.62,0:05:58.02,Default,,0000,0000,0000,,I'll just put A on top of that, \Nand I'll put B on top of that.
Dialogue: 0,0:05:59.22,0:06:01.21,Default,,0000,0000,0000,,Some of you may still not believe me,
Dialogue: 0,0:06:01.21,0:06:04.33,Default,,0000,0000,0000,,so why don't we \Njust move A over on top of B,
Dialogue: 0,0:06:05.67,0:06:07.75,Default,,0000,0000,0000,,or B over on top of A.
Dialogue: 0,0:06:08.78,0:06:12.01,Default,,0000,0000,0000,,No matter how long you look at this, \NA will look darker than B
Dialogue: 0,0:06:12.01,0:06:15.22,Default,,0000,0000,0000,,because your brain's doing \Nsome really groovy stuff,
Dialogue: 0,0:06:15.76,0:06:18.06,Default,,0000,0000,0000,,really quickly, outside of your awareness.
Dialogue: 0,0:06:18.06,0:06:19.16,Default,,0000,0000,0000,,Have a look at this.
Dialogue: 0,0:06:19.16,0:06:22.37,Default,,0000,0000,0000,,Turn your head on the side\Nand have a look at the same picture.
Dialogue: 0,0:06:23.14,0:06:24.63,Default,,0000,0000,0000,,Nothing changes.
Dialogue: 0,0:06:24.63,0:06:26.36,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:06:27.13,0:06:29.43,Default,,0000,0000,0000,,Fantastic. 100% take!
Dialogue: 0,0:06:32.11,0:06:33.93,Default,,0000,0000,0000,,So what really happens here,
Dialogue: 0,0:06:34.74,0:06:37.40,Default,,0000,0000,0000,,exactly the same frequency \Nis hitting your retina,
Dialogue: 0,0:06:38.01,0:06:40.44,Default,,0000,0000,0000,,and that sends a message \Nto the back of the brain,
Dialogue: 0,0:06:40.71,0:06:43.55,Default,,0000,0000,0000,,and then all of this groovy stuff\Nhappens very quickly
Dialogue: 0,0:06:43.55,0:06:46.11,Default,,0000,0000,0000,,to ask the question,\NWhat does this really mean?
Dialogue: 0,0:06:46.11,0:06:48.44,Default,,0000,0000,0000,,What's biologically advantageous for me?
Dialogue: 0,0:06:48.44,0:06:50.27,Default,,0000,0000,0000,,and then you get a visual image.
Dialogue: 0,0:06:50.80,0:06:54.26,Default,,0000,0000,0000,,This is a visual illusion, \Nand vision's not about emotion,
Dialogue: 0,0:06:54.26,0:06:56.41,Default,,0000,0000,0000,,vision's not necessarily about survival,
Dialogue: 0,0:06:56.41,0:06:57.80,Default,,0000,0000,0000,,but pain is.
Dialogue: 0,0:06:58.52,0:07:01.70,Default,,0000,0000,0000,,Now, some of you might not know, \Nif you're not medically trained,
Dialogue: 0,0:07:01.70,0:07:03.89,Default,,0000,0000,0000,,but what's happening\Nat this guy's right leg,
Dialogue: 0,0:07:03.89,0:07:05.56,Default,,0000,0000,0000,,that's not right, that's ...
Dialogue: 0,0:07:05.56,0:07:06.91,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:07:06.91,0:07:08.38,Default,,0000,0000,0000,,that's a dangerous situation,
Dialogue: 0,0:07:08.38,0:07:10.66,Default,,0000,0000,0000,,and that danger message\Narrives at the brain,
Dialogue: 0,0:07:10.66,0:07:13.37,Default,,0000,0000,0000,,and the brain has to ask \Nexactly the same question.
Dialogue: 0,0:07:14.08,0:07:16.29,Default,,0000,0000,0000,,What does this mean? \NWhat should be done here?
Dialogue: 0,0:07:16.30,0:07:22.27,Default,,0000,0000,0000,,And hopefully, the orchestra in this \Nperson's brain will make your leg hurt.
Dialogue: 0,0:07:23.14,0:07:25.52,Default,,0000,0000,0000,,In the work that\NI've been doing for a long time,
Dialogue: 0,0:07:25.52,0:07:30.10,Default,,0000,0000,0000,,we're trying our best to work out \Nhow do we convince people in pain
Dialogue: 0,0:07:30.60,0:07:32.59,Default,,0000,0000,0000,,that we understand they're in pain,
Dialogue: 0,0:07:32.59,0:07:35.25,Default,,0000,0000,0000,,but it's not just about\Nthe tissues of their body.
Dialogue: 0,0:07:36.20,0:07:38.04,Default,,0000,0000,0000,,How do we convince them of that?
Dialogue: 0,0:07:38.04,0:07:42.06,Default,,0000,0000,0000,,And a key conceptual shift\Nthat we think is really important
Dialogue: 0,0:07:42.36,0:07:45.02,Default,,0000,0000,0000,,is that you can understand \Nthat pain is the end result.
Dialogue: 0,0:07:45.02,0:07:48.14,Default,,0000,0000,0000,,Pain's an output of the brain \Ndesigned to protect you.
Dialogue: 0,0:07:50.12,0:07:53.47,Default,,0000,0000,0000,,It's not something that comes\Nfrom the tissues of your body.
Dialogue: 0,0:07:54.54,0:07:56.08,Default,,0000,0000,0000,,There's nothing there.\N
Dialogue: 0,0:07:56.08,0:07:58.10,Default,,0000,0000,0000,,We show patients a really sharp knife,
Dialogue: 0,0:07:58.10,0:08:00.27,Default,,0000,0000,0000,,and we say this knife is sharp, yeah?
Dialogue: 0,0:08:00.28,0:08:01.22,Default,,0000,0000,0000,,Yeah.
Dialogue: 0,0:08:01.64,0:08:04.87,Default,,0000,0000,0000,,And it might be a bit cold;\Nit's hard; it's got all those properties.
Dialogue: 0,0:08:04.87,0:08:07.01,Default,,0000,0000,0000,,This knife - painful as it sits out there.
Dialogue: 0,0:08:07.01,0:08:10.86,Default,,0000,0000,0000,,No, it's not. That knife does not \Nhave the properties of pain.
Dialogue: 0,0:08:11.46,0:08:15.54,Default,,0000,0000,0000,,And when you stick it into their belly -\Nwe do this regularly, straight through -
Dialogue: 0,0:08:16.73,0:08:19.54,Default,,0000,0000,0000,,the belly doesn't adopt \Nthe property of pain.
Dialogue: 0,0:08:19.54,0:08:23.09,Default,,0000,0000,0000,,The brain has to do some \Nvery rapid and groovy things
Dialogue: 0,0:08:23.61,0:08:26.22,Default,,0000,0000,0000,,to project this illusion \Nthat pain exists there.
Dialogue: 0,0:08:26.57,0:08:30.91,Default,,0000,0000,0000,,100% of the time, \Npain is a construct of the brain.
Dialogue: 0,0:08:31.68,0:08:34.45,Default,,0000,0000,0000,,We can mess with pain easily \Nwithout touching the tissues.
Dialogue: 0,0:08:34.45,0:08:36.37,Default,,0000,0000,0000,,This is an experiment we did a while ago
Dialogue: 0,0:08:36.38,0:08:39.40,Default,,0000,0000,0000,,where we got supposedly 'normal'\Nhealthy volunteers.
Dialogue: 0,0:08:39.62,0:08:40.86,Default,,0000,0000,0000,,They're not normal people,
Dialogue: 0,0:08:40.86,0:08:43.25,Default,,0000,0000,0000,,because they're volunteering\Nfor a pain experiment,
Dialogue: 0,0:08:43.25,0:08:44.18,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:08:44.18,0:08:46.90,Default,,0000,0000,0000,,but let's say they are\Nreasonably normal, right,
Dialogue: 0,0:08:46.90,0:08:50.23,Default,,0000,0000,0000,,and we put a very cold piece of metal \Non the back of their hand,
Dialogue: 0,0:08:50.95,0:08:52.89,Default,,0000,0000,0000,,and we just show them one of two lights.
Dialogue: 0,0:08:52.90,0:08:56.12,Default,,0000,0000,0000,,One light is red, and one light is blue.
Dialogue: 0,0:08:56.12,0:08:59.83,Default,,0000,0000,0000,,We don't tell anything about the lights, \Nwe just show them the light.
Dialogue: 0,0:09:02.56,0:09:04.22,Default,,0000,0000,0000,,I see that hand.
Dialogue: 0,0:09:04.79,0:09:06.57,Default,,0000,0000,0000,,We ask them, 'How much does it hurt?'
Dialogue: 0,0:09:06.57,0:09:10.32,Default,,0000,0000,0000,,And if they see the red light, it hurts\Nmore than if they see the blue light.
Dialogue: 0,0:09:10.32,0:09:11.89,Default,,0000,0000,0000,,The stimulus is exactly the same,
Dialogue: 0,0:09:11.89,0:09:14.98,Default,,0000,0000,0000,,what's different is \Nthe meaning of the stimulus.
Dialogue: 0,0:09:14.98,0:09:18.20,Default,,0000,0000,0000,,Now there's a cue that says,\N'This is really hot.'
Dialogue: 0,0:09:18.20,0:09:20.33,Default,,0000,0000,0000,,Because red means hot.
Dialogue: 0,0:09:21.06,0:09:23.69,Default,,0000,0000,0000,,So the sensible brain,\Nthe clever brain should say,
Dialogue: 0,0:09:23.69,0:09:28.52,Default,,0000,0000,0000,,'Well, I really don't want you to do it,\Nso I'm going to make it really hurt.'
Dialogue: 0,0:09:30.68,0:09:34.35,Default,,0000,0000,0000,,There's people in the States that are\Nallowed to get their psychology students
Dialogue: 0,0:09:34.35,0:09:37.22,Default,,0000,0000,0000,,to participate in experiments\Nin exchange for credit points -
Dialogue: 0,0:09:37.22,0:09:39.40,Default,,0000,0000,0000,,or sex, or something -
Dialogue: 0,0:09:39.92,0:09:43.78,Default,,0000,0000,0000,,anyway, they put their head inside what\Nthey think is a stimulator for their head,
Dialogue: 0,0:09:43.78,0:09:47.10,Default,,0000,0000,0000,,and they make sure that\Nthe subject can see the intensity knob.
Dialogue: 0,0:09:47.10,0:09:48.99,Default,,0000,0000,0000,,And as they turn up the intensity knob,
Dialogue: 0,0:09:48.99,0:09:53.59,Default,,0000,0000,0000,,this little figure there showing\Nthe lines going up at a steady rate,
Dialogue: 0,0:09:53.59,0:09:55.60,Default,,0000,0000,0000,,that's their reported head pain,
Dialogue: 0,0:09:55.60,0:09:57.58,Default,,0000,0000,0000,,and it matches the intensity knob.
Dialogue: 0,0:09:57.58,0:09:59.91,Default,,0000,0000,0000,,But the stimulator's doing nothing.
Dialogue: 0,0:09:59.91,0:10:02.53,Default,,0000,0000,0000,,It's just one of those\Nold-fashioned plastic hair dryers
Dialogue: 0,0:10:02.53,0:10:03.76,Default,,0000,0000,0000,,that doesn't do anything.
Dialogue: 0,0:10:03.76,0:10:05.39,Default,,0000,0000,0000,,You know those things?
Dialogue: 0,0:10:05.39,0:10:08.23,Default,,0000,0000,0000,,You probably use one - yeah?
Dialogue: 0,0:10:08.89,0:10:11.72,Default,,0000,0000,0000,,The trick is that they\Nhave to see the intensity knob.
Dialogue: 0,0:10:12.96,0:10:15.12,Default,,0000,0000,0000,,I always think it'd be fun\Nto do an experiment
Dialogue: 0,0:10:15.12,0:10:18.89,Default,,0000,0000,0000,,based on that Spinal Tap film\Nwhere the intensity knob goes up to 11.
Dialogue: 0,0:10:19.38,0:10:21.26,Default,,0000,0000,0000,,Remember that film?
Dialogue: 0,0:10:21.88,0:10:24.30,Default,,0000,0000,0000,,What's really important\Nfrom a clinical perspective,
Dialogue: 0,0:10:24.30,0:10:28.02,Default,,0000,0000,0000,,and I'm a clinical neuroscientist,\Nand I see patients in pain,
Dialogue: 0,0:10:28.02,0:10:31.54,Default,,0000,0000,0000,,any piece of credible evidence\Nthat they're in danger
Dialogue: 0,0:10:31.54,0:10:33.06,Default,,0000,0000,0000,,should change their pain,
Dialogue: 0,0:10:33.06,0:10:35.36,Default,,0000,0000,0000,,and they're all walking\Ninto hospital departments
Dialogue: 0,0:10:35.36,0:10:37.28,Default,,0000,0000,0000,,with models like this on the desk.
Dialogue: 0,0:10:37.60,0:10:39.64,Default,,0000,0000,0000,,What does your brain say\Nwhen it sees a disc
Dialogue: 0,0:10:39.64,0:10:42.39,Default,,0000,0000,0000,,that's slipped so far out\Nit's sitting on its own?
Dialogue: 0,0:10:42.39,0:10:43.81,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:10:44.68,0:10:49.56,Default,,0000,0000,0000,,If you've ever seen a disc in a cadaver,\Nyou can't slip the suckers.
Dialogue: 0,0:10:49.95,0:10:52.61,Default,,0000,0000,0000,,They're immobile, you can't slip a disc.
Dialogue: 0,0:10:52.87,0:10:55.66,Default,,0000,0000,0000,,But that's our language,\Nand it messes with your brain.
Dialogue: 0,0:10:55.66,0:10:58.61,Default,,0000,0000,0000,,It cannot not mess with your brain.
Dialogue: 0,0:10:59.44,0:11:03.47,Default,,0000,0000,0000,,We can even modulate the location of pain.\NWe can do some groovy things.
Dialogue: 0,0:11:03.89,0:11:06.17,Default,,0000,0000,0000,,It's quite well established\Nthat referred pain
Dialogue: 0,0:11:06.17,0:11:10.55,Default,,0000,0000,0000,,gives you pain in an area of your body\Nthat might be physiologically normal.
Dialogue: 0,0:11:11.08,0:11:13.23,Default,,0000,0000,0000,,Most of you would have heard\Nof referred pain.
Dialogue: 0,0:11:13.23,0:11:14.25,Default,,0000,0000,0000,,(Sneezing)
Dialogue: 0,0:11:14.25,0:11:15.29,Default,,0000,0000,0000,,Bless you.
Dialogue: 0,0:11:15.29,0:11:18.42,Default,,0000,0000,0000,,We do experiments where we give you\Npain in an artificial limb -
Dialogue: 0,0:11:18.42,0:11:19.78,Default,,0000,0000,0000,,it's not even yours.
Dialogue: 0,0:11:19.78,0:11:23.68,Default,,0000,0000,0000,,This is Meng, who was a postdoc\Nin my lab in Oxford in the UK,
Dialogue: 0,0:11:23.68,0:11:25.40,Default,,0000,0000,0000,,and we stole a prosthetic limb,
Dialogue: 0,0:11:25.41,0:11:28.17,Default,,0000,0000,0000,,which is a whole other story\Nwhich is really funny -
Dialogue: 0,0:11:28.17,0:11:29.67,Default,,0000,0000,0000,,but I won't tell it to you -
Dialogue: 0,0:11:29.67,0:11:32.64,Default,,0000,0000,0000,,\Nand we can do this manipulation
Dialogue: 0,0:11:32.64,0:11:36.37,Default,,0000,0000,0000,,so that you start to feel like\Nthe plastic limb in front of you is yours.
Dialogue: 0,0:11:37.22,0:11:39.42,Default,,0000,0000,0000,,And we can make the rubber hand hurt.
Dialogue: 0,0:11:39.42,0:11:44.66,Default,,0000,0000,0000,,And we can bring in a knife,\Nand run the knife across the rubber hand,
Dialogue: 0,0:11:44.66,0:11:48.13,Default,,0000,0000,0000,,and you have your brain responses\Nto protect that rubber hand.
Dialogue: 0,0:11:48.48,0:11:52.65,Default,,0000,0000,0000,,You're feeling pain\Nin a lump of plastic, effectively.
Dialogue: 0,0:11:53.36,0:11:57.44,Default,,0000,0000,0000,,Here's a groovy experiment where\Nwe take two Microsoft clipart people,
Dialogue: 0,0:11:57.44,0:12:01.17,Default,,0000,0000,0000,,and we put a webcam\Non the forehead of one of them
Dialogue: 0,0:12:01.17,0:12:04.89,Default,,0000,0000,0000,,and a set of virtual reality glasses\Non the other one.
Dialogue: 0,0:12:06.15,0:12:08.44,Default,,0000,0000,0000,,And then we get them to shake hands.
Dialogue: 0,0:12:08.44,0:12:10.13,Default,,0000,0000,0000,,And as they're shaking hands,
Dialogue: 0,0:12:10.13,0:12:14.30,Default,,0000,0000,0000,,the person on your right,\Nwho's wearing the goggles,
Dialogue: 0,0:12:15.01,0:12:18.65,Default,,0000,0000,0000,,their visual field is coming\Nfrom the other person's forehead.
Dialogue: 0,0:12:18.65,0:12:19.94,Default,,0000,0000,0000,,Have you got it?
Dialogue: 0,0:12:20.01,0:12:24.16,Default,,0000,0000,0000,,So they are effectively looking\Nat the other person, thinking it's them
Dialogue: 0,0:12:24.16,0:12:28.49,Default,,0000,0000,0000,,because they're shaking hands,\Nthe motor command fits, everything's good.
Dialogue: 0,0:12:28.49,0:12:32.98,Default,,0000,0000,0000,,And then we come in and put\Na painful stimulus on that person's arm,
Dialogue: 0,0:12:32.99,0:12:36.31,Default,,0000,0000,0000,,and they see it hit that arm\Nof the person over there,
Dialogue: 0,0:12:36.31,0:12:40.55,Default,,0000,0000,0000,,with whom they're shaking hands,\Nand they say, 'Ouch! It really hurts.'
Dialogue: 0,0:12:40.55,0:12:42.16,Default,,0000,0000,0000,,And we say, 'Where does it hurt?'
Dialogue: 0,0:12:42.16,0:12:43.90,Default,,0000,0000,0000,,'On that man's arm.'
Dialogue: 0,0:12:43.90,0:12:45.73,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:12:45.73,0:12:48.51,Default,,0000,0000,0000,,They get it right every time,\Npointing exactly where it is,
Dialogue: 0,0:12:48.51,0:12:51.65,Default,,0000,0000,0000,,but if you were on the outside,\Ntaking a photo, they're literally -
Dialogue: 0,0:12:51.65,0:12:55.46,Default,,0000,0000,0000,,we've got the painful stimulus here,\Nand they're saying, 'It hurts there.'
Dialogue: 0,0:12:55.88,0:12:59.75,Default,,0000,0000,0000,,So the brain is not only producing pain,
Dialogue: 0,0:12:59.75,0:13:02.75,Default,,0000,0000,0000,,it's projecting it\Nto this location in mid-air.
Dialogue: 0,0:13:03.21,0:13:04.85,Default,,0000,0000,0000,,We can mess with that.
Dialogue: 0,0:13:04.85,0:13:07.29,Default,,0000,0000,0000,,This all becomes really important\Nwhen pain persists
Dialogue: 0,0:13:07.30,0:13:09.100,Default,,0000,0000,0000,,because two things happen\Nwhen pain persists
Dialogue: 0,0:13:09.100,0:13:12.56,Default,,0000,0000,0000,,that make the life\Nof someone in pain really difficult,
Dialogue: 0,0:13:12.56,0:13:15.52,Default,,0000,0000,0000,,that costs our country\N40 billion dollars a year.
Dialogue: 0,0:13:15.67,0:13:17.64,Default,,0000,0000,0000,,It costs Australia more than cancer,
Dialogue: 0,0:13:17.64,0:13:20.100,Default,,0000,0000,0000,,cardio-vascular disease\Nand diabetes combined.
Dialogue: 0,0:13:21.98,0:13:25.98,Default,,0000,0000,0000,,Thanks for that facial expression,\NI wanted someone to go ...
Dialogue: 0,0:13:27.94,0:13:30.75,Default,,0000,0000,0000,,This is the problem,\Nthat if we keep running the neurons,
Dialogue: 0,0:13:30.75,0:13:34.74,Default,,0000,0000,0000,,the brain cells that produce pain,\Nthey get better at producing pain.
Dialogue: 0,0:13:35.08,0:13:36.80,Default,,0000,0000,0000,,They become more and more sensitive,
Dialogue: 0,0:13:36.80,0:13:38.90,Default,,0000,0000,0000,,so we need a smaller\Nand smaller influence.
Dialogue: 0,0:13:38.90,0:13:42.24,Default,,0000,0000,0000,,The illusion, if you like,\Nin increasing sensitivity
Dialogue: 0,0:13:43.37,0:13:44.85,Default,,0000,0000,0000,,becomes very unhelpful.
Dialogue: 0,0:13:44.85,0:13:48.63,Default,,0000,0000,0000,,It's trying to protect you from something\Nthat's not needing protection.
Dialogue: 0,0:13:49.11,0:13:50.22,Default,,0000,0000,0000,,It's very real.
Dialogue: 0,0:13:50.73,0:13:53.49,Default,,0000,0000,0000,,The other thing that happens\Nis that all of these networks
Dialogue: 0,0:13:53.49,0:13:57.99,Default,,0000,0000,0000,,lose their capacity to be specific\Nand precise, so the pain spreads.
Dialogue: 0,0:13:58.30,0:14:02.75,Default,,0000,0000,0000,,The pain changes its quality.\NUltimately, it's not even informative.
Dialogue: 0,0:14:02.75,0:14:05.50,Default,,0000,0000,0000,,It's both unhelpful and uninformative.
Dialogue: 0,0:14:06.68,0:14:10.47,Default,,0000,0000,0000,,Maybe the next TED Talk ever\Nis the really important question,
Dialogue: 0,0:14:10.47,0:14:12.21,Default,,0000,0000,0000,,'What do we do about it?'
Dialogue: 0,0:14:13.11,0:14:14.53,Default,,0000,0000,0000,,Who knows?
Dialogue: 0,0:14:14.100,0:14:15.100,Default,,0000,0000,0000,,No, we do know,
Dialogue: 0,0:14:15.100,0:14:19.73,Default,,0000,0000,0000,,that's what we're really researching,\Nbut that's the end of my 18 minutes.
Dialogue: 0,0:14:19.73,0:14:21.87,Default,,0000,0000,0000,,Thank you very much for having me.
Dialogue: 0,0:14:21.87,0:14:25.13,Default,,0000,0000,0000,,(Applause)