[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.80,0:00:03.14,Default,,0000,0000,0000,,I'm going to talk\Nabout the strategizing brain.
Dialogue: 0,0:00:03.16,0:00:05.54,Default,,0000,0000,0000,,We're going to use\Nan unusual combination of tools
Dialogue: 0,0:00:05.56,0:00:07.18,Default,,0000,0000,0000,,from game theory and neuroscience
Dialogue: 0,0:00:07.20,0:00:10.46,Default,,0000,0000,0000,,to understand how people interact socially\Nwhen value is on the line.
Dialogue: 0,0:00:10.48,0:00:14.02,Default,,0000,0000,0000,,So game theory is a branch\Nof, originally, applied mathematics,
Dialogue: 0,0:00:14.04,0:00:16.26,Default,,0000,0000,0000,,used mostly in economics\Nand political science,
Dialogue: 0,0:00:16.28,0:00:17.54,Default,,0000,0000,0000,,a little bit in biology,
Dialogue: 0,0:00:17.56,0:00:20.34,Default,,0000,0000,0000,,that gives us a mathematical\Ntaxonomy of social life
Dialogue: 0,0:00:20.36,0:00:22.66,Default,,0000,0000,0000,,and it predicts\Nwhat people are likely to do
Dialogue: 0,0:00:22.68,0:00:23.98,Default,,0000,0000,0000,,and believe others will do
Dialogue: 0,0:00:24.00,0:00:27.02,Default,,0000,0000,0000,,in cases where everyone's actions\Naffect everyone else.
Dialogue: 0,0:00:27.04,0:00:30.70,Default,,0000,0000,0000,,That's a lot of things:\Ncompetition, cooperation, bargaining,
Dialogue: 0,0:00:30.72,0:00:33.28,Default,,0000,0000,0000,,games like hide-and-seek and poker.
Dialogue: 0,0:00:33.92,0:00:35.86,Default,,0000,0000,0000,,Here's a simple game to get us started.
Dialogue: 0,0:00:35.88,0:00:38.30,Default,,0000,0000,0000,,Everyone chooses a number\Nfrom zero to 100,
Dialogue: 0,0:00:38.32,0:00:40.78,Default,,0000,0000,0000,,we're going to compute\Nthe average of those numbers,
Dialogue: 0,0:00:40.80,0:00:44.82,Default,,0000,0000,0000,,and whoever's closest to two-thirds\Nof the average wins a fixed prize.
Dialogue: 0,0:00:44.84,0:00:47.62,Default,,0000,0000,0000,,So you want to be\Na little bit below the average number,
Dialogue: 0,0:00:47.64,0:00:48.90,Default,,0000,0000,0000,,but not too far below,
Dialogue: 0,0:00:48.92,0:00:50.34,Default,,0000,0000,0000,,and everyone else wants to be
Dialogue: 0,0:00:50.36,0:00:52.54,Default,,0000,0000,0000,,a little bit below\Nthe average number as well.
Dialogue: 0,0:00:52.56,0:00:54.14,Default,,0000,0000,0000,,Think about what you might pick.
Dialogue: 0,0:00:54.16,0:00:55.38,Default,,0000,0000,0000,,As you're thinking,
Dialogue: 0,0:00:55.40,0:00:58.46,Default,,0000,0000,0000,,this is a toy model of something\Nlike selling in the stock market
Dialogue: 0,0:00:58.48,0:00:59.94,Default,,0000,0000,0000,,during a rising market. Right?
Dialogue: 0,0:00:59.96,0:01:02.66,Default,,0000,0000,0000,,You don't want to sell too early\Nand miss out on profits,
Dialogue: 0,0:01:02.68,0:01:04.38,Default,,0000,0000,0000,,but you don't want to wait too late
Dialogue: 0,0:01:04.40,0:01:06.64,Default,,0000,0000,0000,,to when everyone else sells,\Ntriggering a crash.
Dialogue: 0,0:01:06.66,0:01:09.16,Default,,0000,0000,0000,,You want to be a little bit\Nahead of the competition,
Dialogue: 0,0:01:09.18,0:01:10.38,Default,,0000,0000,0000,,but not too far ahead.
Dialogue: 0,0:01:10.40,0:01:13.42,Default,,0000,0000,0000,,OK, here's two theories\Nabout how people might think about this,
Dialogue: 0,0:01:13.44,0:01:14.66,Default,,0000,0000,0000,,then we'll see some data.
Dialogue: 0,0:01:14.68,0:01:16.30,Default,,0000,0000,0000,,Some of these will sound familiar
Dialogue: 0,0:01:16.32,0:01:18.38,Default,,0000,0000,0000,,because you probably\Nare thinking that way.
Dialogue: 0,0:01:18.40,0:01:20.00,Default,,0000,0000,0000,,I'm using my brain theory to see.
Dialogue: 0,0:01:20.72,0:01:24.14,Default,,0000,0000,0000,,A lot of people say, "I really don't know\Nwhat people are going to pick,
Dialogue: 0,0:01:24.16,0:01:25.86,Default,,0000,0000,0000,,so I think the average will be 50."
Dialogue: 0,0:01:25.88,0:01:27.90,Default,,0000,0000,0000,,They're not being really strategic at all.
Dialogue: 0,0:01:27.92,0:01:30.94,Default,,0000,0000,0000,,"And I'll pick two-thirds of 50.\NThat's 33." That's a start.
Dialogue: 0,0:01:30.96,0:01:33.30,Default,,0000,0000,0000,,Other people who are\Na little more sophisticated,
Dialogue: 0,0:01:33.32,0:01:34.62,Default,,0000,0000,0000,,using more working memory,
Dialogue: 0,0:01:34.64,0:01:36.26,Default,,0000,0000,0000,,say, "I think people will pick 33
Dialogue: 0,0:01:36.28,0:01:38.50,Default,,0000,0000,0000,,because they're going to pick\Na response to 50,
Dialogue: 0,0:01:38.52,0:01:40.86,Default,,0000,0000,0000,,and so I'll pick 22,\Nwhich is two-thirds of 33."
Dialogue: 0,0:01:40.88,0:01:43.82,Default,,0000,0000,0000,,They're doing one extra step\Nof thinking, two steps.
Dialogue: 0,0:01:43.84,0:01:45.02,Default,,0000,0000,0000,,That's better.
Dialogue: 0,0:01:45.04,0:01:47.78,Default,,0000,0000,0000,,And in principle,\Nyou could do three, four or more,
Dialogue: 0,0:01:47.80,0:01:49.74,Default,,0000,0000,0000,,but it starts to get very difficult.
Dialogue: 0,0:01:49.76,0:01:51.70,Default,,0000,0000,0000,,Just like in language and other domains,
Dialogue: 0,0:01:51.72,0:01:54.58,Default,,0000,0000,0000,,we know it's hard for people\Nto parse very complex sentences
Dialogue: 0,0:01:54.60,0:01:55.94,Default,,0000,0000,0000,,with a recursive structure.
Dialogue: 0,0:01:55.96,0:01:58.14,Default,,0000,0000,0000,,This is called the cognitive\Nhierarchy theory.
Dialogue: 0,0:01:58.16,0:02:00.90,Default,,0000,0000,0000,,It's something that I've worked on\Nand a few other people,
Dialogue: 0,0:02:00.92,0:02:03.58,Default,,0000,0000,0000,,and it indicates a hierarchy\Nalong with some assumptions
Dialogue: 0,0:02:03.60,0:02:05.74,Default,,0000,0000,0000,,about how many people\Nstop at different steps
Dialogue: 0,0:02:05.76,0:02:09.30,Default,,0000,0000,0000,,and how the steps of thinking are affected\Nby lots of interesting variables
Dialogue: 0,0:02:09.32,0:02:11.46,Default,,0000,0000,0000,,and variant people,\Nas we'll see in a minute.
Dialogue: 0,0:02:11.48,0:02:14.66,Default,,0000,0000,0000,,A very different theory,\Na much more popular one, and an older one,
Dialogue: 0,0:02:14.68,0:02:17.18,Default,,0000,0000,0000,,due largely to John Nash\Nof "A Beautiful Mind" fame,
Dialogue: 0,0:02:17.20,0:02:19.38,Default,,0000,0000,0000,,is what's called equilibrium analysis.
Dialogue: 0,0:02:19.40,0:02:22.14,Default,,0000,0000,0000,,So if you've ever taken\Na game theory course at any level,
Dialogue: 0,0:02:22.16,0:02:24.34,Default,,0000,0000,0000,,you will have learned\Na little bit about this.
Dialogue: 0,0:02:24.36,0:02:26.22,Default,,0000,0000,0000,,An equilibrium is a mathematical state
Dialogue: 0,0:02:26.24,0:02:29.58,Default,,0000,0000,0000,,in which everybody has figured out\Nexactly what everyone else will do.
Dialogue: 0,0:02:29.60,0:02:30.98,Default,,0000,0000,0000,,It is a very useful concept,
Dialogue: 0,0:02:31.00,0:02:33.78,Default,,0000,0000,0000,,but behaviorally, it may not\Nexactly explain what people do
Dialogue: 0,0:02:33.80,0:02:36.34,Default,,0000,0000,0000,,the first time they play\Nthese types of economic games
Dialogue: 0,0:02:36.36,0:02:38.22,Default,,0000,0000,0000,,or in situations in the outside world.
Dialogue: 0,0:02:38.24,0:02:41.02,Default,,0000,0000,0000,,In this case, the equilibrium\Nmakes a very bold prediction,
Dialogue: 0,0:02:41.04,0:02:43.42,Default,,0000,0000,0000,,which is everyone wants\Nto be below everyone else,
Dialogue: 0,0:02:43.44,0:02:45.00,Default,,0000,0000,0000,,therefore they'll play zero.
Dialogue: 0,0:02:45.68,0:02:46.90,Default,,0000,0000,0000,,Let's see what happens.
Dialogue: 0,0:02:46.92,0:02:49.06,Default,,0000,0000,0000,,This experiment's been done\Nmany, many times.
Dialogue: 0,0:02:49.08,0:02:51.30,Default,,0000,0000,0000,,Some of the earliest ones\Nwere done in the '90s
Dialogue: 0,0:02:51.32,0:02:53.14,Default,,0000,0000,0000,,by me and Rosemarie Nagel and others.
Dialogue: 0,0:02:53.16,0:02:55.62,Default,,0000,0000,0000,,This is a beautiful data set\Nof 9,000 people
Dialogue: 0,0:02:55.64,0:02:58.82,Default,,0000,0000,0000,,who wrote in to three newspapers\Nand magazines that had a contest.
Dialogue: 0,0:02:58.84,0:03:00.86,Default,,0000,0000,0000,,The contest said, send in your numbers
Dialogue: 0,0:03:00.88,0:03:04.30,Default,,0000,0000,0000,,and whoever is closer to two-thirds\Nof the average will win a big prize.
Dialogue: 0,0:03:04.32,0:03:06.50,Default,,0000,0000,0000,,And as you can see,\Nthere's so much data here,
Dialogue: 0,0:03:06.52,0:03:08.26,Default,,0000,0000,0000,,you can see the spikes very visibly.
Dialogue: 0,0:03:08.28,0:03:10.90,Default,,0000,0000,0000,,There's a spike at 33.\NThose are people doing one step.
Dialogue: 0,0:03:10.92,0:03:12.94,Default,,0000,0000,0000,,There is another spike visible at 22.
Dialogue: 0,0:03:12.96,0:03:15.82,Default,,0000,0000,0000,,And notice that most people\Npick numbers right around there.
Dialogue: 0,0:03:15.84,0:03:18.02,Default,,0000,0000,0000,,They don't necessarily pick\Nexactly 33 and 22.
Dialogue: 0,0:03:18.04,0:03:20.26,Default,,0000,0000,0000,,There's something\Na little bit noisy around it.
Dialogue: 0,0:03:20.28,0:03:21.70,Default,,0000,0000,0000,,But you can see those spikes.
Dialogue: 0,0:03:21.72,0:03:23.26,Default,,0000,0000,0000,,There's another group of people
Dialogue: 0,0:03:23.28,0:03:25.78,Default,,0000,0000,0000,,who seem to have\Na firm grip on equilibrium analysis,
Dialogue: 0,0:03:25.80,0:03:27.54,Default,,0000,0000,0000,,because they're picking zero or one.
Dialogue: 0,0:03:27.56,0:03:29.58,Default,,0000,0000,0000,,But they lose, right?
Dialogue: 0,0:03:29.60,0:03:32.90,Default,,0000,0000,0000,,Because picking a number that low\Nis actually a bad choice
Dialogue: 0,0:03:32.92,0:03:35.66,Default,,0000,0000,0000,,if other people aren't\Ndoing equilibrium analysis as well.
Dialogue: 0,0:03:35.68,0:03:37.10,Default,,0000,0000,0000,,So they're smart, but poor.
Dialogue: 0,0:03:37.12,0:03:39.50,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:03:39.52,0:03:42.06,Default,,0000,0000,0000,,Where are these things\Nhappening in the brain?
Dialogue: 0,0:03:42.08,0:03:45.74,Default,,0000,0000,0000,,One study by Coricelli and Nagel\Ngives a really sharp, interesting answer.
Dialogue: 0,0:03:45.76,0:03:49.54,Default,,0000,0000,0000,,So they had people play this game\Nwhile they were being scanned in an fMRI,
Dialogue: 0,0:03:49.56,0:03:51.82,Default,,0000,0000,0000,,and two conditions:\Nin some trials, they're told
Dialogue: 0,0:03:51.84,0:03:54.34,Default,,0000,0000,0000,,you're playing another person\Nwho's playing right now
Dialogue: 0,0:03:54.36,0:03:57.46,Default,,0000,0000,0000,,and we're going to match up your behavior\Nand pay you if you win.
Dialogue: 0,0:03:57.48,0:04:00.38,Default,,0000,0000,0000,,In the other trials, they're told,\Nyou're playing a computer.
Dialogue: 0,0:04:00.40,0:04:01.94,Default,,0000,0000,0000,,They're just choosing randomly.
Dialogue: 0,0:04:01.96,0:04:04.14,Default,,0000,0000,0000,,So what you see\Nhere is a subtraction of areas
Dialogue: 0,0:04:04.16,0:04:07.14,Default,,0000,0000,0000,,in which there's more brain activity\Nwhen you're playing people
Dialogue: 0,0:04:07.16,0:04:08.78,Default,,0000,0000,0000,,compared to playing the computer.
Dialogue: 0,0:04:08.80,0:04:11.34,Default,,0000,0000,0000,,And you see activity\Nin some regions we've seen today,
Dialogue: 0,0:04:11.36,0:04:13.70,Default,,0000,0000,0000,,medial prefrontal cortex,\Ndorsomedial, up here,
Dialogue: 0,0:04:13.72,0:04:16.14,Default,,0000,0000,0000,,ventromedial prefrontal cortex,\Nanterior cingulate,
Dialogue: 0,0:04:16.16,0:04:19.18,Default,,0000,0000,0000,,an area that's involved\Nin lots of types of conflict resolution,
Dialogue: 0,0:04:19.20,0:04:21.06,Default,,0000,0000,0000,,like if you're playing "Simon Says,"
Dialogue: 0,0:04:21.08,0:04:24.26,Default,,0000,0000,0000,,and also the right and left\Ntemporoparietal junction.
Dialogue: 0,0:04:24.28,0:04:26.90,Default,,0000,0000,0000,,And these are all areas\Nwhich are fairly reliably known
Dialogue: 0,0:04:26.92,0:04:29.54,Default,,0000,0000,0000,,to be part of what's called\Na "theory of mind" circuit,
Dialogue: 0,0:04:29.56,0:04:30.82,Default,,0000,0000,0000,,or "mentalizing circuit."
Dialogue: 0,0:04:30.84,0:04:34.34,Default,,0000,0000,0000,,That is, it's a circuit that's used\Nto imagine what other people might do.
Dialogue: 0,0:04:34.36,0:04:36.78,Default,,0000,0000,0000,,So these were some\Nof the first studies to see this
Dialogue: 0,0:04:36.80,0:04:38.00,Default,,0000,0000,0000,,tied in to game theory.
Dialogue: 0,0:04:38.72,0:04:40.98,Default,,0000,0000,0000,,What happens with these\None- and two-step types?
Dialogue: 0,0:04:41.00,0:04:43.22,Default,,0000,0000,0000,,So we classify people by what they picked
Dialogue: 0,0:04:43.24,0:04:47.18,Default,,0000,0000,0000,,and then we look at the difference between\Nplaying humans versus playing computers,
Dialogue: 0,0:04:47.20,0:04:49.30,Default,,0000,0000,0000,,which brain areas\Nare differentially active.
Dialogue: 0,0:04:49.32,0:04:52.26,Default,,0000,0000,0000,,On the top you see the one-step players.\NAlmost no difference.
Dialogue: 0,0:04:52.28,0:04:55.50,Default,,0000,0000,0000,,They're treating other people\Nlike a computer, and the brain is too.
Dialogue: 0,0:04:55.52,0:04:58.66,Default,,0000,0000,0000,,The bottom players, you see\Nall the activity in dorsomedial PFC.
Dialogue: 0,0:04:58.68,0:05:01.42,Default,,0000,0000,0000,,So those two-step players\Nare doing something differently.
Dialogue: 0,0:05:01.44,0:05:03.98,Default,,0000,0000,0000,,You could say, "What can we do\Nwith this information?"
Dialogue: 0,0:05:04.00,0:05:05.50,Default,,0000,0000,0000,,You might be able to say,
Dialogue: 0,0:05:05.52,0:05:07.78,Default,,0000,0000,0000,,"This person's going to be\Na good poker player,"
Dialogue: 0,0:05:07.80,0:05:09.50,Default,,0000,0000,0000,,or, "This person's socially naive,"
Dialogue: 0,0:05:09.52,0:05:11.47,Default,,0000,0000,0000,,and we might also be able to study things
Dialogue: 0,0:05:11.50,0:05:13.30,Default,,0000,0000,0000,,like development of adolescent brains
Dialogue: 0,0:05:13.32,0:05:15.78,Default,,0000,0000,0000,,once we have an idea\Nof where this circuitry exists.
Dialogue: 0,0:05:15.80,0:05:17.90,Default,,0000,0000,0000,,OK. Get ready.
Dialogue: 0,0:05:17.92,0:05:19.94,Default,,0000,0000,0000,,I'm saving you some brain activity,
Dialogue: 0,0:05:19.96,0:05:22.70,Default,,0000,0000,0000,,because you don't need\Nto use your hair detector cells.
Dialogue: 0,0:05:22.72,0:05:25.98,Default,,0000,0000,0000,,You should use those cells\Nto think carefully about this game.
Dialogue: 0,0:05:26.00,0:05:27.50,Default,,0000,0000,0000,,This is a bargaining game.
Dialogue: 0,0:05:27.52,0:05:30.54,Default,,0000,0000,0000,,Two players who are being scanned\Nusing EEG electrodes
Dialogue: 0,0:05:30.56,0:05:33.34,Default,,0000,0000,0000,,are going to bargain\Nover one to six dollars.
Dialogue: 0,0:05:33.36,0:05:36.90,Default,,0000,0000,0000,,If they can do it in 10 seconds,\Nthey're going to actually earn that money.
Dialogue: 0,0:05:36.92,0:05:38.98,Default,,0000,0000,0000,,If they don't make a deal,\Nthey get nothing.
Dialogue: 0,0:05:39.00,0:05:40.62,Default,,0000,0000,0000,,That's a mistake together.
Dialogue: 0,0:05:40.64,0:05:43.46,Default,,0000,0000,0000,,The twist is that one player, on the left,
Dialogue: 0,0:05:43.48,0:05:45.86,Default,,0000,0000,0000,,is informed about how much\Non each trial there is.
Dialogue: 0,0:05:45.88,0:05:48.62,Default,,0000,0000,0000,,They play lots of trials\Nwith different amounts each time.
Dialogue: 0,0:05:48.64,0:05:50.78,Default,,0000,0000,0000,,In this case, they know\Nthere's four dollars.
Dialogue: 0,0:05:50.80,0:05:54.42,Default,,0000,0000,0000,,The uninformed player doesn't know,\Nbut they know the informed player knows.
Dialogue: 0,0:05:54.44,0:05:56.66,Default,,0000,0000,0000,,So the uninformed player's\Nchallenge is to say,
Dialogue: 0,0:05:56.68,0:05:59.94,Default,,0000,0000,0000,,"Is this guy really being fair\Nor are they giving me a very low offer
Dialogue: 0,0:05:59.96,0:06:01.30,Default,,0000,0000,0000,,in order to get me to think
Dialogue: 0,0:06:01.32,0:06:04.02,Default,,0000,0000,0000,,that there's only one\Nor two dollars available to split?"
Dialogue: 0,0:06:04.04,0:06:06.78,Default,,0000,0000,0000,,In which case they might reject it\Nand not come to a deal.
Dialogue: 0,0:06:06.80,0:06:09.66,Default,,0000,0000,0000,,So there's some tension\Nbetween trying to get the most money
Dialogue: 0,0:06:09.68,0:06:12.38,Default,,0000,0000,0000,,but trying to goad the other player\Ninto giving you more.
Dialogue: 0,0:06:12.40,0:06:14.90,Default,,0000,0000,0000,,And the way they bargain\Nis to point on a number line
Dialogue: 0,0:06:14.92,0:06:16.62,Default,,0000,0000,0000,,that goes from zero to six dollars,
Dialogue: 0,0:06:16.64,0:06:19.66,Default,,0000,0000,0000,,and they're bargaining\Nover how much the uninformed player gets,
Dialogue: 0,0:06:19.68,0:06:21.50,Default,,0000,0000,0000,,and the informed player gets the rest.
Dialogue: 0,0:06:21.52,0:06:23.70,Default,,0000,0000,0000,,So this is like\Na management-labor negotiation
Dialogue: 0,0:06:23.72,0:06:25.22,Default,,0000,0000,0000,,in which the workers don't know
Dialogue: 0,0:06:25.24,0:06:28.22,Default,,0000,0000,0000,,how much profits\Nthe privately held company has,
Dialogue: 0,0:06:28.24,0:06:30.78,Default,,0000,0000,0000,,and they want to maybe\Nhold out for more money,
Dialogue: 0,0:06:30.80,0:06:33.22,Default,,0000,0000,0000,,but the company might want\Nto create the impression
Dialogue: 0,0:06:33.24,0:06:36.42,Default,,0000,0000,0000,,that there's little to split:\N"I'm giving you the most that I can."
Dialogue: 0,0:06:36.44,0:06:37.70,Default,,0000,0000,0000,,First some behavior.
Dialogue: 0,0:06:37.72,0:06:40.10,Default,,0000,0000,0000,,So a bunch of the subject pairs\Nplay face to face.
Dialogue: 0,0:06:40.12,0:06:42.58,Default,,0000,0000,0000,,We have other data\Nwhere they play across computers.
Dialogue: 0,0:06:42.60,0:06:44.22,Default,,0000,0000,0000,,That's an interesting difference.
Dialogue: 0,0:06:44.24,0:06:46.06,Default,,0000,0000,0000,,But a bunch of the face-to-face pairs
Dialogue: 0,0:06:46.08,0:06:48.48,Default,,0000,0000,0000,,agree to divide the money evenly\Nevery single time.
Dialogue: 0,0:06:49.20,0:06:52.22,Default,,0000,0000,0000,,Boring. It's just\Nnot interesting neurally.
Dialogue: 0,0:06:52.24,0:06:54.46,Default,,0000,0000,0000,,It's good for them.\NThey make a lot of money.
Dialogue: 0,0:06:54.48,0:06:55.98,Default,,0000,0000,0000,,But we're interested in,
Dialogue: 0,0:06:56.00,0:06:59.36,Default,,0000,0000,0000,,can we say something about when\Ndisagreements occur versus don't occur?
Dialogue: 0,0:06:59.88,0:07:02.62,Default,,0000,0000,0000,,So this is the other group of subjects\Nwho often disagree.
Dialogue: 0,0:07:02.64,0:07:03.98,Default,,0000,0000,0000,,So they have a chance of --
Dialogue: 0,0:07:04.00,0:07:06.46,Default,,0000,0000,0000,,they bicker and disagree\Nand end up with less money.
Dialogue: 0,0:07:06.48,0:07:09.44,Default,,0000,0000,0000,,They might be eligible\Nto be on "Real Housewives," the TV show.
Dialogue: 0,0:07:10.24,0:07:11.90,Default,,0000,0000,0000,,You see on the left,
Dialogue: 0,0:07:11.92,0:07:14.54,Default,,0000,0000,0000,,when the amount to divide\Nis one, two or three dollars,
Dialogue: 0,0:07:14.56,0:07:16.22,Default,,0000,0000,0000,,they disagree about half the time,
Dialogue: 0,0:07:16.24,0:07:19.22,Default,,0000,0000,0000,,and when the amount is four, five, six,\Nthey agree quite often.
Dialogue: 0,0:07:19.24,0:07:21.46,Default,,0000,0000,0000,,This turns out to be\Nsomething that's predicted
Dialogue: 0,0:07:21.48,0:07:23.43,Default,,0000,0000,0000,,by a very complicated type of game theory
Dialogue: 0,0:07:23.46,0:07:26.38,Default,,0000,0000,0000,,you should come to graduate school\Nat CalTech and learn about.
Dialogue: 0,0:07:26.40,0:07:28.82,Default,,0000,0000,0000,,It's a little too complicated\Nto explain right now,
Dialogue: 0,0:07:28.84,0:07:31.78,Default,,0000,0000,0000,,but the theory tells you\Nthat this shape kind of should occur.
Dialogue: 0,0:07:31.80,0:07:33.70,Default,,0000,0000,0000,,Your intuition might tell you that too.
Dialogue: 0,0:07:33.72,0:07:36.22,Default,,0000,0000,0000,,Now I'll show you\Nthe results from the EEG recording.
Dialogue: 0,0:07:36.24,0:07:39.50,Default,,0000,0000,0000,,Very complicated. The right brain\Nschematic is the uninformed person,
Dialogue: 0,0:07:39.52,0:07:40.94,Default,,0000,0000,0000,,and the left is the informed.
Dialogue: 0,0:07:40.96,0:07:43.74,Default,,0000,0000,0000,,Remember that we scanned\Nboth brains at the same time,
Dialogue: 0,0:07:43.76,0:07:46.06,Default,,0000,0000,0000,,so we can ask about time-synced activity
Dialogue: 0,0:07:46.08,0:07:49.10,Default,,0000,0000,0000,,in similar or different\Nareas simultaneously,
Dialogue: 0,0:07:49.12,0:07:51.34,Default,,0000,0000,0000,,just like if you wanted\Nto study a conversation
Dialogue: 0,0:07:51.36,0:07:53.94,Default,,0000,0000,0000,,and you were scanning\Ntwo people talking to each other
Dialogue: 0,0:07:53.96,0:07:56.42,Default,,0000,0000,0000,,and you'd expect common activity\Nin language regions
Dialogue: 0,0:07:56.44,0:07:58.82,Default,,0000,0000,0000,,when they're actually\Nlistening and communicating.
Dialogue: 0,0:07:58.84,0:08:02.10,Default,,0000,0000,0000,,So the arrows connect regions\Nthat are active at the same time,
Dialogue: 0,0:08:02.12,0:08:03.94,Default,,0000,0000,0000,,and the direction of the arrows flows
Dialogue: 0,0:08:03.96,0:08:06.26,Default,,0000,0000,0000,,from the region\Nthat's active first in time,
Dialogue: 0,0:08:06.28,0:08:10.06,Default,,0000,0000,0000,,and the arrowhead goes\Nto the region that's active later.
Dialogue: 0,0:08:10.08,0:08:12.14,Default,,0000,0000,0000,,So in this case, if you look carefully,
Dialogue: 0,0:08:12.16,0:08:14.18,Default,,0000,0000,0000,,most of the arrows\Nflow from right to left.
Dialogue: 0,0:08:14.20,0:08:19.14,Default,,0000,0000,0000,,That is, it looks as if the uninformed\Nbrain activity is happening first
Dialogue: 0,0:08:19.16,0:08:23.02,Default,,0000,0000,0000,,and then it's followed\Nby activity in the informed brain.
Dialogue: 0,0:08:23.04,0:08:26.46,Default,,0000,0000,0000,,And by the way, these were trials\Nwhere their deals were made.
Dialogue: 0,0:08:26.48,0:08:28.26,Default,,0000,0000,0000,,This is from the first two seconds.
Dialogue: 0,0:08:28.28,0:08:31.38,Default,,0000,0000,0000,,We haven't finished analyzing this data,\Nwe're still peeking in,
Dialogue: 0,0:08:31.40,0:08:34.82,Default,,0000,0000,0000,,but the hope is that we can say\Nsomething in the first couple of seconds
Dialogue: 0,0:08:34.84,0:08:36.82,Default,,0000,0000,0000,,about whether they'll make a deal or not,
Dialogue: 0,0:08:36.84,0:08:38.98,Default,,0000,0000,0000,,which could be useful\Nin avoiding litigation,
Dialogue: 0,0:08:39.00,0:08:40.70,Default,,0000,0000,0000,,ugly divorces and things like that.
Dialogue: 0,0:08:40.72,0:08:41.94,Default,,0000,0000,0000,,Those are all cases
Dialogue: 0,0:08:41.96,0:08:45.20,Default,,0000,0000,0000,,in which a lot of value\Nis lost by delay and strikes.
Dialogue: 0,0:08:46.56,0:08:48.74,Default,,0000,0000,0000,,Here's the case\Nwhere the disagreements occur.
Dialogue: 0,0:08:48.76,0:08:51.18,Default,,0000,0000,0000,,You can see it looks different\Nthan the one before.
Dialogue: 0,0:08:51.20,0:08:52.54,Default,,0000,0000,0000,,There's a lot more arrows.
Dialogue: 0,0:08:52.56,0:08:54.50,Default,,0000,0000,0000,,That means that the brains are synced up
Dialogue: 0,0:08:54.52,0:08:56.78,Default,,0000,0000,0000,,more closely in terms\Nof simultaneous activity,
Dialogue: 0,0:08:56.80,0:08:59.02,Default,,0000,0000,0000,,and the arrows flow clearly\Nfrom left to right.
Dialogue: 0,0:08:59.04,0:09:01.38,Default,,0000,0000,0000,,That is, the informed brain\Nseems to be deciding,
Dialogue: 0,0:09:01.40,0:09:03.62,Default,,0000,0000,0000,,"We're probably\Nnot going to make a deal here."
Dialogue: 0,0:09:03.64,0:09:06.28,Default,,0000,0000,0000,,And then later there's activity\Nin the uninformed brain.
Dialogue: 0,0:09:06.80,0:09:09.18,Default,,0000,0000,0000,,Next I'm going to introduce you\Nto some relatives.
Dialogue: 0,0:09:09.20,0:09:11.34,Default,,0000,0000,0000,,They're hairy, smelly, fast and strong.
Dialogue: 0,0:09:11.36,0:09:13.86,Default,,0000,0000,0000,,You might be thinking back\Nto your last Thanksgiving.
Dialogue: 0,0:09:13.88,0:09:14.90,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:09:14.92,0:09:17.34,Default,,0000,0000,0000,,Maybe if you had a chimpanzee with you.
Dialogue: 0,0:09:17.36,0:09:21.30,Default,,0000,0000,0000,,Charles Darwin and I and you broke off\Nfrom the family tree, from chimpanzees,
Dialogue: 0,0:09:21.32,0:09:22.90,Default,,0000,0000,0000,,about five million years ago.
Dialogue: 0,0:09:22.92,0:09:24.78,Default,,0000,0000,0000,,They're still our closest genetic kin.
Dialogue: 0,0:09:24.80,0:09:26.50,Default,,0000,0000,0000,,We share 98.8 percent of the genes.
Dialogue: 0,0:09:26.52,0:09:29.38,Default,,0000,0000,0000,,We share more genes with them\Nthan zebras do with horses.
Dialogue: 0,0:09:29.40,0:09:31.30,Default,,0000,0000,0000,,And we're also their closest cousin.
Dialogue: 0,0:09:31.32,0:09:34.02,Default,,0000,0000,0000,,They have more genetic relation\Nto us than to gorillas.
Dialogue: 0,0:09:34.04,0:09:36.70,Default,,0000,0000,0000,,So how humans and chimpanzees\Nbehave differently
Dialogue: 0,0:09:36.72,0:09:38.76,Default,,0000,0000,0000,,might tell us a lot about brain evolution.
Dialogue: 0,0:09:39.32,0:09:41.70,Default,,0000,0000,0000,,So this is an amazing memory test
Dialogue: 0,0:09:41.72,0:09:44.46,Default,,0000,0000,0000,,from Nagoya, Japan,\NPrimate Research Institute,
Dialogue: 0,0:09:44.48,0:09:46.50,Default,,0000,0000,0000,,where they've done a lot of this research.
Dialogue: 0,0:09:46.52,0:09:47.90,Default,,0000,0000,0000,,This goes back quite a ways.
Dialogue: 0,0:09:47.92,0:09:49.74,Default,,0000,0000,0000,,They're interested in working memory.
Dialogue: 0,0:09:49.76,0:09:52.62,Default,,0000,0000,0000,,The chimp is going to see\N200 milliseconds' exposure --
Dialogue: 0,0:09:52.64,0:09:54.70,Default,,0000,0000,0000,,that's fast, that's eight movie frames --
Dialogue: 0,0:09:54.72,0:09:56.62,Default,,0000,0000,0000,,of numbers one, two, three, four, five.
Dialogue: 0,0:09:56.64,0:09:59.10,Default,,0000,0000,0000,,Then they disappear\Nand they're replaced by squares,
Dialogue: 0,0:09:59.12,0:10:00.78,Default,,0000,0000,0000,,and they have to press the squares
Dialogue: 0,0:10:00.80,0:10:04.18,Default,,0000,0000,0000,,that correspond to the numbers\Nfrom low to high to get an apple reward.
Dialogue: 0,0:10:04.20,0:10:05.60,Default,,0000,0000,0000,,Let's see how they can do it.
Dialogue: 0,0:10:16.40,0:10:17.66,Default,,0000,0000,0000,,This is a young chimp.
Dialogue: 0,0:10:17.68,0:10:20.78,Default,,0000,0000,0000,,The young ones are better\Nthan the old ones, just like humans.
Dialogue: 0,0:10:20.80,0:10:22.34,Default,,0000,0000,0000,,And they're highly experienced,
Dialogue: 0,0:10:22.36,0:10:24.86,Default,,0000,0000,0000,,so they've done this\Nthousands and thousands of time.
Dialogue: 0,0:10:24.88,0:10:27.90,Default,,0000,0000,0000,,Obviously there's a big training effect,\Nas you can imagine.
Dialogue: 0,0:10:27.92,0:10:29.42,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:10:29.44,0:10:32.02,Default,,0000,0000,0000,,You can see they're very blasé\Nand kind of effortless.
Dialogue: 0,0:10:32.04,0:10:35.26,Default,,0000,0000,0000,,Not only can they do it very well,\Nthey do it in a sort of lazy way.
Dialogue: 0,0:10:35.28,0:10:37.10,Default,,0000,0000,0000,,Who thinks you could beat the chimps?
Dialogue: 0,0:10:37.12,0:10:38.54,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:10:38.56,0:10:39.78,Default,,0000,0000,0000,,Wrong.
Dialogue: 0,0:10:39.80,0:10:40.82,Default,,0000,0000,0000,,(Laughter)
Dialogue: 0,0:10:40.84,0:10:42.82,Default,,0000,0000,0000,,We can try. Maybe we'll try.
Dialogue: 0,0:10:42.84,0:10:46.86,Default,,0000,0000,0000,,OK, so the next part of this study\NI'm going to go quickly through
Dialogue: 0,0:10:46.88,0:10:49.82,Default,,0000,0000,0000,,is based on an idea of Tetsuro Matsuzawa.
Dialogue: 0,0:10:49.84,0:10:51.10,Default,,0000,0000,0000,,He had a bold idea --
Dialogue: 0,0:10:51.12,0:10:53.50,Default,,0000,0000,0000,,what he called the cognitive\Ntrade-off hypothesis.
Dialogue: 0,0:10:53.52,0:10:57.26,Default,,0000,0000,0000,,We know chimps are faster and stronger.\NThey're also very obsessed with status.
Dialogue: 0,0:10:57.28,0:11:00.02,Default,,0000,0000,0000,,His thought was, maybe\Nthey've preserved brain activities,
Dialogue: 0,0:11:00.04,0:11:01.90,Default,,0000,0000,0000,,and they practice them in development,
Dialogue: 0,0:11:01.92,0:11:04.98,Default,,0000,0000,0000,,that are really important to them\Nto negotiate status and to win,
Dialogue: 0,0:11:05.00,0:11:07.94,Default,,0000,0000,0000,,which is something like strategic thinking\Nduring competition.
Dialogue: 0,0:11:07.96,0:11:11.90,Default,,0000,0000,0000,,So we're going to check that out\Nby having the chimps actually play a game
Dialogue: 0,0:11:11.92,0:11:14.42,Default,,0000,0000,0000,,by touching two touch screens.
Dialogue: 0,0:11:14.44,0:11:17.50,Default,,0000,0000,0000,,The chimps are interacting\Nwith each other through the computers.
Dialogue: 0,0:11:17.52,0:11:20.74,Default,,0000,0000,0000,,They're going to press left or right.\NOne chimp is called a matcher.
Dialogue: 0,0:11:20.76,0:11:22.42,Default,,0000,0000,0000,,They win if they press left, left,
Dialogue: 0,0:11:22.44,0:11:25.54,Default,,0000,0000,0000,,like a seeker finding someone\Nin hide-and-seek, or right, right.
Dialogue: 0,0:11:25.56,0:11:27.18,Default,,0000,0000,0000,,The mismatcher wants to mismatch.
Dialogue: 0,0:11:27.20,0:11:29.90,Default,,0000,0000,0000,,They want to press\Nthe opposite screen of the chimp.
Dialogue: 0,0:11:29.92,0:11:31.80,Default,,0000,0000,0000,,And the rewards are apple cube rewards.
Dialogue: 0,0:11:32.40,0:11:34.74,Default,,0000,0000,0000,,So here's how game theorists\Nlook at these data.
Dialogue: 0,0:11:34.76,0:11:39.02,Default,,0000,0000,0000,,This is a graph of the percentage of times\Nthe matcher picked right on the x-axis,
Dialogue: 0,0:11:39.04,0:11:41.30,Default,,0000,0000,0000,,and the percentage of times\Nthey predicted right
Dialogue: 0,0:11:41.32,0:11:43.42,Default,,0000,0000,0000,,by the mismatcher on the y-axis.
Dialogue: 0,0:11:43.44,0:11:46.78,Default,,0000,0000,0000,,So a point here is the behavior\Nby a pair of players,
Dialogue: 0,0:11:46.80,0:11:49.02,Default,,0000,0000,0000,,one trying to match,\None trying to mismatch.
Dialogue: 0,0:11:49.04,0:11:52.38,Default,,0000,0000,0000,,The NE square in the middle --\Nactually NE, CH and QRE --
Dialogue: 0,0:11:52.40,0:11:55.66,Default,,0000,0000,0000,,those are three different theories\Nof Nash equilibrium, and others --
Dialogue: 0,0:11:55.68,0:11:57.38,Default,,0000,0000,0000,,tells you what the theory predicts,
Dialogue: 0,0:11:57.40,0:11:59.38,Default,,0000,0000,0000,,which is that they should match 50-50,
Dialogue: 0,0:11:59.40,0:12:01.70,Default,,0000,0000,0000,,because if you play\Nleft too much, for example,
Dialogue: 0,0:12:01.72,0:12:04.78,Default,,0000,0000,0000,,I can exploit that if I'm the mismatcher\Nby then playing right.
Dialogue: 0,0:12:04.80,0:12:07.78,Default,,0000,0000,0000,,And as you can see, the chimps --\Neach chimp is one triangle --
Dialogue: 0,0:12:07.80,0:12:10.24,Default,,0000,0000,0000,,are circled around,\Nhovering around that prediction.
Dialogue: 0,0:12:11.12,0:12:12.86,Default,,0000,0000,0000,,Now we move the payoffs.
Dialogue: 0,0:12:12.88,0:12:15.98,Default,,0000,0000,0000,,We're going to make the left, left payoff\Nfor the matcher higher.
Dialogue: 0,0:12:16.00,0:12:17.50,Default,,0000,0000,0000,,Now they get three apple cubes.
Dialogue: 0,0:12:17.52,0:12:20.78,Default,,0000,0000,0000,,Game theoretically, that should\Nmake the mismatcher's behavior shift,
Dialogue: 0,0:12:20.80,0:12:22.46,Default,,0000,0000,0000,,because the mismatcher will think,
Dialogue: 0,0:12:22.48,0:12:24.48,Default,,0000,0000,0000,,this guy's going to go for the big reward,
Dialogue: 0,0:12:24.50,0:12:27.38,Default,,0000,0000,0000,,so I'm going to go to the right,\Nmake sure he doesn't get it.
Dialogue: 0,0:12:27.40,0:12:28.74,Default,,0000,0000,0000,,And their behavior moves up
Dialogue: 0,0:12:28.76,0:12:32.06,Default,,0000,0000,0000,,in the direction of this change\Nin the Nash equilibrium.
Dialogue: 0,0:12:32.08,0:12:34.30,Default,,0000,0000,0000,,Finally, we changed\Nthe payoffs one more time.
Dialogue: 0,0:12:34.32,0:12:35.58,Default,,0000,0000,0000,,Now it's four apple cubes,
Dialogue: 0,0:12:35.60,0:12:38.46,Default,,0000,0000,0000,,and their behavior again\Nmoves towards the Nash equilibrium.
Dialogue: 0,0:12:38.48,0:12:41.18,Default,,0000,0000,0000,,It's sprinkled around,\Nbut if you average the chimps out,
Dialogue: 0,0:12:41.20,0:12:42.82,Default,,0000,0000,0000,,they're really close, within .01.
Dialogue: 0,0:12:42.84,0:12:45.50,Default,,0000,0000,0000,,They're actually closer\Nthan any species we've observed.
Dialogue: 0,0:12:45.52,0:12:46.74,Default,,0000,0000,0000,,What about humans?
Dialogue: 0,0:12:46.76,0:12:48.80,Default,,0000,0000,0000,,You think you're smarter\Nthan a chimpanzee?
Dialogue: 0,0:12:49.32,0:12:51.92,Default,,0000,0000,0000,,Here's two human groups in green and blue.
Dialogue: 0,0:12:52.60,0:12:53.82,Default,,0000,0000,0000,,They're closer to 50-50.
Dialogue: 0,0:12:53.84,0:12:55.98,Default,,0000,0000,0000,,They're not responding\Nto payoffs as closely,
Dialogue: 0,0:12:56.00,0:12:57.58,Default,,0000,0000,0000,,and if you study their learning,
Dialogue: 0,0:12:57.60,0:12:59.74,Default,,0000,0000,0000,,they aren't as sensitive\Nto previous rewards.
Dialogue: 0,0:12:59.76,0:13:01.94,Default,,0000,0000,0000,,The chimps are playing better\Nthan the humans,
Dialogue: 0,0:13:01.96,0:13:03.90,Default,,0000,0000,0000,,in the sense of adhering to game theory.
Dialogue: 0,0:13:03.92,0:13:06.90,Default,,0000,0000,0000,,These are two different groups\Nof humans from Japan and Africa.
Dialogue: 0,0:13:06.92,0:13:08.30,Default,,0000,0000,0000,,They replicate quite nicely.
Dialogue: 0,0:13:08.32,0:13:10.54,Default,,0000,0000,0000,,None of them are close\Nto where the chimps are.
Dialogue: 0,0:13:10.56,0:13:12.70,Default,,0000,0000,0000,,OK, so here are some things\Nwe learned today.
Dialogue: 0,0:13:12.72,0:13:15.38,Default,,0000,0000,0000,,People seem to do a limited\Namount of strategic thinking
Dialogue: 0,0:13:15.40,0:13:16.66,Default,,0000,0000,0000,,using theory of mind.
Dialogue: 0,0:13:16.68,0:13:18.50,Default,,0000,0000,0000,,We have some evidence from bargaining
Dialogue: 0,0:13:18.52,0:13:21.46,Default,,0000,0000,0000,,that early warning signs in the brain\Nmight be used to predict
Dialogue: 0,0:13:21.48,0:13:24.22,Default,,0000,0000,0000,,whether there will be\Na bad disagreement that costs money,
Dialogue: 0,0:13:24.24,0:13:26.42,Default,,0000,0000,0000,,and chimps are better\Ncompetitors than humans,
Dialogue: 0,0:13:26.44,0:13:27.66,Default,,0000,0000,0000,,as judged by game theory.
Dialogue: 0,0:13:27.68,0:13:28.90,Default,,0000,0000,0000,,Thank you.
Dialogue: 0,0:13:28.92,0:13:32.48,Default,,0000,0000,0000,,(Applause)