WEBVTT 00:00:00.770 --> 00:00:03.200 The following content is provided under a Creative 00:00:03.200 --> 00:00:04.610 Commons license. 00:00:04.610 --> 00:00:07.640 Your support will help MIT OpenCourseWare continue to 00:00:07.640 --> 00:00:11.300 offer high quality educational resources for free. 00:00:11.300 --> 00:00:14.190 To make a donation, or view additional materials from 00:00:14.190 --> 00:00:20.020 hundreds of MIT courses, visit MIT OpenCourseWare at 00:00:20.020 --> 00:00:21.270 ocw.mit.edu. 00:00:33.370 --> 00:00:36.850 PROFESSOR: OK, good afternoon. 00:00:36.850 --> 00:00:40.146 Today's lecture is going to be on child development. 00:00:40.146 --> 00:00:44.195 How they go from infancy and head towards adulthood. 00:00:44.195 --> 00:00:48.668 Next Thursday we'll talk about development after infancy and 00:00:48.668 --> 00:00:51.153 into adulthood and over age. 00:00:51.153 --> 00:00:53.935 And this amazing thing about babies and how do they get 00:00:53.935 --> 00:00:56.850 going, and how do scientists discover from babies and young 00:00:56.850 --> 00:00:59.340 children how their minds are fundamentally 00:00:59.340 --> 00:01:01.680 different than adults. 00:01:01.680 --> 00:01:04.739 And how your mind was fundamentally different than 00:01:04.739 --> 00:01:05.580 it is as an adult. 00:01:05.580 --> 00:01:10.230 And then the last thing will be a dangerous experiment, 00:01:10.230 --> 00:01:13.420 where my wife will come over with my two-year-old and my 00:01:13.420 --> 00:01:15.370 four-year-old and we'll try to do a developmental 00:01:15.370 --> 00:01:16.520 demonstration in front of you. 00:01:16.520 --> 00:01:19.520 But I should warn you that live children 00:01:19.520 --> 00:01:20.420 have their own will. 00:01:20.420 --> 00:01:23.280 So we'll see how that goes, okay? 00:01:23.280 --> 00:01:24.420 All right. 00:01:24.420 --> 00:01:28.080 So one thing that people are struck by babies is that 00:01:28.080 --> 00:01:29.680 babies are cute. 00:01:29.680 --> 00:01:32.300 And it's not just-- 00:01:32.300 --> 00:01:35.780 It's thought to be not just fun, but kind of a really 00:01:35.780 --> 00:01:37.570 important biological thing. 00:01:37.570 --> 00:01:39.310 We talked about motherese before. 00:01:39.310 --> 00:01:42.410 Singsong talk to babies that help them learn a language. 00:01:42.410 --> 00:01:45.710 There's something about adults finding babies cute that makes 00:01:45.710 --> 00:01:47.760 them want to help babies. 00:01:47.760 --> 00:01:49.550 Parents and friends-- 00:01:49.550 --> 00:01:54.620 The cuteness is thought to be an evolutionary reward for 00:01:54.620 --> 00:01:56.640 dealing with a baby. 00:01:56.640 --> 00:01:58.270 And people have said, well what is it that's a little bit 00:01:58.270 --> 00:02:00.710 different about a baby's face than an adult? 00:02:00.710 --> 00:02:03.190 They have rounder heads, they have foreheads that protrude 00:02:03.190 --> 00:02:05.670 more towards-- 00:02:05.670 --> 00:02:06.850 that slope back more. 00:02:06.850 --> 00:02:09.330 They have larger eyes proportionately. 00:02:09.330 --> 00:02:12.130 Smaller jaw bones proportionally. 00:02:12.130 --> 00:02:14.800 And people use the term neotony to describe this kind 00:02:14.800 --> 00:02:17.730 of infant proportions, or properties, of faces, which 00:02:17.730 --> 00:02:19.620 are universal. 00:02:19.620 --> 00:02:22.320 And, of course, a lot of people discover this in 00:02:22.320 --> 00:02:24.070 advertising or cartoons. 00:02:24.070 --> 00:02:28.040 And so here's an interesting example of how Mickey Mouse 00:02:28.040 --> 00:02:30.710 has, over the years, from the original version of Mickey 00:02:30.710 --> 00:02:35.100 Mouse to the current super cute, super tested, super 00:02:35.100 --> 00:02:38.620 Disney version of Mickey Mouse, has become increasingly 00:02:38.620 --> 00:02:39.400 neotonized. 00:02:39.400 --> 00:02:42.180 And how much the cartoonists literally know that, or just 00:02:42.180 --> 00:02:44.490 have kept saying, what makes cuter, and cuter, and cuter, 00:02:44.490 --> 00:02:47.015 and ended up with a lot of the same proportions in Mickey 00:02:47.015 --> 00:02:51.370 Mouse's face that make infants so cute and desirable. 00:02:51.370 --> 00:02:52.020 We don't really know. 00:02:52.020 --> 00:02:55.780 But the world kind of feels this. 00:02:55.780 --> 00:02:57.640 Even adult research-- there's a little funny line of 00:02:57.640 --> 00:03:02.410 research-- that says adults who look more baby-faced get 00:03:02.410 --> 00:03:04.225 treated a little bit different socially. 00:03:07.950 --> 00:03:10.330 So here's Leonardo DiCaprio. 00:03:10.330 --> 00:03:14.150 And baby-faced adults in experiments are perceived as, 00:03:14.150 --> 00:03:17.030 just by their faces, as more naive, more honest, more 00:03:17.030 --> 00:03:20.660 helpless, more kind, more warm. 00:03:20.660 --> 00:03:23.640 People think, this is going to be a nice warm person. 00:03:23.640 --> 00:03:26.980 Guessing from faces they're using the cues of neotony. 00:03:26.980 --> 00:03:30.170 Other studies have found that people who are baby-faced are 00:03:30.170 --> 00:03:34.200 statistically more likely to be found innocent in cases of 00:03:34.200 --> 00:03:36.070 intentional wrongdoing. 00:03:36.070 --> 00:03:38.760 So where they're trying to prove if somebody on purpose 00:03:38.760 --> 00:03:40.190 tried to do something bad, they go, not 00:03:40.190 --> 00:03:42.670 that cute little person. 00:03:42.670 --> 00:03:45.560 But there's no difference if it's cases that involve 00:03:45.560 --> 00:03:46.240 negligence. 00:03:46.240 --> 00:03:47.280 Something where you should have done something. 00:03:47.280 --> 00:03:49.640 Because we know babies aren't super responsible 00:03:49.640 --> 00:03:50.890 for how they behave. 00:03:55.470 --> 00:03:58.820 And they're less likely to receive votes in elections. 00:03:58.820 --> 00:04:00.100 So people have done-- 00:04:00.100 --> 00:04:01.710 I won't even tell you this-- but people have done all kinds 00:04:01.710 --> 00:04:04.405 of analyses of faces that win elections in the US 00:04:04.405 --> 00:04:05.680 and around the world. 00:04:05.680 --> 00:04:07.270 And there's two dimensions that people look for. 00:04:07.270 --> 00:04:09.890 What looks like somebody's empathetic and what looks like 00:04:09.890 --> 00:04:11.760 somebody's competent. 00:04:11.760 --> 00:04:14.010 So you want babies when it's fun, but when you have to 00:04:14.010 --> 00:04:16.260 figure out how to balance the budget that doesn't seem like 00:04:16.260 --> 00:04:18.399 a baby task. 00:04:18.399 --> 00:04:20.079 So it's kind of funny. 00:04:20.079 --> 00:04:25.680 And a lot of voters go by instincts as well as by facts 00:04:25.680 --> 00:04:27.440 or stated values. 00:04:27.440 --> 00:04:31.610 So in the development of infants into adults, the 00:04:31.610 --> 00:04:34.990 classic debates about how our mind grasps the world have 00:04:34.990 --> 00:04:37.520 played out, yet again, in a powerful way. 00:04:37.520 --> 00:04:38.970 You know, the nature-nurture debate. 00:04:38.970 --> 00:04:41.190 What's in our genes and gets us going? 00:04:41.190 --> 00:04:43.990 What's acquired from the environment? 00:04:43.990 --> 00:04:47.100 Philosophers who say that knowledge starts with innate, 00:04:47.100 --> 00:04:50.810 or genetic, or more evolved capacities. 00:04:50.810 --> 00:04:53.180 Other ones who've emphasized that we pick it up from the 00:04:53.180 --> 00:04:57.560 world empirically as measuring scientists. 00:04:57.560 --> 00:05:00.540 So, for example, Aristotle wrote, "There's nothing in the 00:05:00.540 --> 00:05:03.430 intellect which was not first in the senses." that's the 00:05:03.430 --> 00:05:04.310 empirical view. 00:05:04.310 --> 00:05:06.900 It's out there in the world and you solve it. 00:05:06.900 --> 00:05:09.200 And starting with a blank slate. 00:05:09.200 --> 00:05:11.980 And, in fact, the behaviorists believed in this with a 00:05:11.980 --> 00:05:13.540 vengeance in psychology. 00:05:13.540 --> 00:05:15.960 So Watson wrote, "Give me a dozen healthy infants, well 00:05:15.960 --> 00:05:18.980 formed, and my own specified world to bring them up. 00:05:18.980 --> 00:05:21.400 And I'll guarantee to take any of them, one at random, and 00:05:21.400 --> 00:05:24.610 train him to become any type of specialist I might select. 00:05:24.610 --> 00:05:26.910 A doctor, lawyer, artist, merchant, chief, and, yes, 00:05:26.910 --> 00:05:28.140 even beggerman and thief. 00:05:28.140 --> 00:05:30.660 That it's all the environment and a blank slate. 00:05:30.660 --> 00:05:33.700 And who really knows?" 00:05:33.700 --> 00:05:36.220 But infants are born with some incredible things, an we'll 00:05:36.220 --> 00:05:37.470 talk about them today. 00:05:37.470 --> 00:05:38.985 One of them is this experiment from Andy 00:05:38.985 --> 00:05:41.790 Meltzoff, which is this. 00:05:41.790 --> 00:05:45.460 That it seems like within moments of birth, infants are 00:05:45.460 --> 00:05:50.090 equipped with a desire to imitate adults. 00:05:50.090 --> 00:05:52.010 A desire to imitate. 00:05:52.010 --> 00:05:54.550 And why people have been really impressed by this is, 00:05:54.550 --> 00:05:58.900 if you have that in your genes and in your nature, it's a 00:05:58.900 --> 00:06:02.090 good way to learn about the world is to imitate people you 00:06:02.090 --> 00:06:03.070 see around you. 00:06:03.070 --> 00:06:04.930 It's kind of a driving principal. 00:06:04.930 --> 00:06:08.760 I'll imitate their language, their social mores. 00:06:08.760 --> 00:06:10.390 Here's what Meltzoff did. 00:06:10.390 --> 00:06:14.440 Sticks out his tongue, opens his mouth, purses his lips. 00:06:14.440 --> 00:06:18.960 And here's the infant, one day or a couple days old, tongue 00:06:18.960 --> 00:06:22.700 out, mouth open, lips pursed. 00:06:22.700 --> 00:06:24.510 Now, I should warn you about one thing. 00:06:24.510 --> 00:06:26.860 These are the greatest hits pieces of that research. 00:06:26.860 --> 00:06:28.480 People debate about how perfectly this 00:06:28.480 --> 00:06:29.600 happens, all right? 00:06:29.600 --> 00:06:32.070 So I was frustrated when my infant came home and I did all 00:06:32.070 --> 00:06:34.560 this stuff and she would not instantly do everything she 00:06:34.560 --> 00:06:35.830 was supposed to do. 00:06:35.830 --> 00:06:37.050 It's a statistical thing. 00:06:37.050 --> 00:06:39.230 Because when you see these pictures, they're showing you 00:06:39.230 --> 00:06:40.300 the best moments. 00:06:40.300 --> 00:06:43.090 They have to defend that it happens above chances 00:06:43.090 --> 00:06:43.720 statistically. 00:06:43.720 --> 00:06:45.370 But it's not like every expression you 00:06:45.370 --> 00:06:47.170 make they copy you. 00:06:47.170 --> 00:06:49.290 And that's why there's still some debate about exactly 00:06:49.290 --> 00:06:50.130 what's going on. 00:06:50.130 --> 00:06:53.740 But they definitely, on average, imitate an adult 00:06:53.740 --> 00:06:56.590 within a day or two of birth for completely arbitrary-- 00:06:56.590 --> 00:06:57.660 as far as we think-- 00:06:57.660 --> 00:06:58.900 expressions. 00:06:58.900 --> 00:07:01.400 So it's a very powerful mechanism for learning that 00:07:01.400 --> 00:07:02.410 appears to be in place. 00:07:02.410 --> 00:07:05.800 Because there's two ways that we could imagine genetically 00:07:05.800 --> 00:07:07.320 programmed learning. 00:07:07.320 --> 00:07:10.660 One is that you know the content of it already. 00:07:10.660 --> 00:07:12.760 But another way is that you just have stuff 00:07:12.760 --> 00:07:14.340 that makes you a learner. 00:07:14.340 --> 00:07:17.270 So being an imitator is a general way to make you a 00:07:17.270 --> 00:07:21.990 learner without being very specific to the content. 00:07:21.990 --> 00:07:24.680 So we talked a little bit about this already, but 00:07:24.680 --> 00:07:26.630 psychologists are unbelievably brilliant-- 00:07:26.630 --> 00:07:28.980 I think, I'm really blown away-- about how they can 00:07:28.980 --> 00:07:32.010 figure out when an infant knows and doesn't know, or 00:07:32.010 --> 00:07:33.740 young child knows or doesn't know. 00:07:33.740 --> 00:07:36.610 And they do this indirectly by things like looking time. 00:07:36.610 --> 00:07:37.550 And you've seen this. 00:07:37.550 --> 00:07:38.450 I'll give you an example or two. 00:07:38.450 --> 00:07:39.840 And you'll see some more examples. 00:07:39.840 --> 00:07:42.360 As a measure of what the baby knows, or 00:07:42.360 --> 00:07:43.690 the young child knows. 00:07:43.690 --> 00:07:45.760 And, of course, if they look longer at something it could 00:07:45.760 --> 00:07:48.220 be because they prefer it. 00:07:48.220 --> 00:07:51.760 And, also, if it's based on a memory task-- 00:07:51.760 --> 00:07:53.420 like you saw something, you see it again-- 00:07:53.420 --> 00:07:55.090 that would tell you there's some sort of discrimination . 00:07:55.090 --> 00:07:58.630 They can tell things apart based on memory. 00:07:58.630 --> 00:08:00.850 And then, sometimes, people will push this memory thing 00:08:00.850 --> 00:08:02.710 with habituation or familiarization, so if you 00:08:02.710 --> 00:08:07.490 show something to a baby over, and over, and over again, they 00:08:07.490 --> 00:08:09.140 get sort of tired of it. 00:08:09.140 --> 00:08:11.570 And at that moment they'll change the stimulus. 00:08:11.570 --> 00:08:15.050 And they'll see whether the baby gets newly attentive. 00:08:15.050 --> 00:08:18.340 Now, if it's something that the baby doesn't grasp, they 00:08:18.340 --> 00:08:19.610 won't get newly attentive. 00:08:19.610 --> 00:08:21.640 You know, nothing's changed in their mind. 00:08:21.640 --> 00:08:25.030 If it's something the baby understands, then they'll say, 00:08:25.030 --> 00:08:26.530 wow, something interesting is happening. 00:08:26.530 --> 00:08:28.210 And they'll look longer. 00:08:28.210 --> 00:08:30.070 So, here's an example. 00:08:30.070 --> 00:08:32.364 Baby getting bored because they're showing something over 00:08:32.364 --> 00:08:34.740 and over, and something new, oh! 00:08:34.740 --> 00:08:36.289 That's the kind of things that people measure. 00:08:36.289 --> 00:08:37.710 And we're doing it loosely here. 00:08:37.710 --> 00:08:38.740 They measure it pretty carefully. 00:08:38.740 --> 00:08:40.789 I should tell you, the people who do this kind of research-- 00:08:40.789 --> 00:08:44.800 they'll film it, they'll show it to unbiased people like 00:08:44.800 --> 00:08:45.760 you, maybe judges. 00:08:45.760 --> 00:08:47.790 OK, to say, how long is the baby looking? 00:08:47.790 --> 00:08:48.260 Where's it looking? 00:08:48.260 --> 00:08:51.300 You don't know where the baby should be looking at or not. 00:08:51.300 --> 00:08:54.230 So researchers take care to make it not just that you're 00:08:54.230 --> 00:08:55.680 convinced in your heart of hearts that 00:08:55.680 --> 00:08:56.370 they're looking more. 00:08:56.370 --> 00:08:57.290 They film it. 00:08:57.290 --> 00:08:58.970 They show it to people who don't know what's going on. 00:08:58.970 --> 00:09:01.010 They try to make it a blind procedure in many ways, the 00:09:01.010 --> 00:09:02.440 better research. 00:09:02.440 --> 00:09:03.610 So how do we know things? 00:09:03.610 --> 00:09:06.910 Even very young infants look selectively at novel objects. 00:09:06.910 --> 00:09:10.410 If something's new, even at one day, if you show them 00:09:10.410 --> 00:09:14.900 checkerboards with different size squares, same size, same 00:09:14.900 --> 00:09:18.850 size, same size, wait a couple seconds, smaller squares. 00:09:18.850 --> 00:09:20.240 They look more. 00:09:20.240 --> 00:09:22.520 This shows you they saw the difference in the squares. 00:09:22.520 --> 00:09:25.560 They even remember, somehow in their mind, the difference 00:09:25.560 --> 00:09:26.620 between the squares. 00:09:26.620 --> 00:09:28.890 Because when you switch it they start looking more. 00:09:28.890 --> 00:09:31.580 Something interesting has happened based on perception 00:09:31.580 --> 00:09:34.080 and memory. 00:09:34.080 --> 00:09:35.140 Another thing that we've mentioned-- 00:09:35.140 --> 00:09:37.290 I'll just remind you-- is that infants, almost from birth, 00:09:37.290 --> 00:09:40.720 seem to love to control, or provoke, their environment. 00:09:40.720 --> 00:09:43.350 So we already mentioned to you that 20 month olds prefer a 00:09:43.350 --> 00:09:46.310 mobile that responds to their bodily movements. 00:09:46.310 --> 00:09:47.940 They like things that they control. 00:09:47.940 --> 00:09:50.610 If they take a two-month-old, and they put a string on their 00:09:50.610 --> 00:09:53.509 wrist by which they can control a showing of Sesame 00:09:53.509 --> 00:09:57.260 Street, they kind of like that. 00:09:57.260 --> 00:09:59.910 And if you stop Sesame Street, they show anger on their face. 00:09:59.910 --> 00:10:03.210 Hey, I was in charge here, who has the remote control now. 00:10:03.210 --> 00:10:05.875 And four and five month olds, a little bit older, remain 00:10:05.875 --> 00:10:09.190 angry when the video comes back on because that's not 00:10:09.190 --> 00:10:09.930 what they wanted. 00:10:09.930 --> 00:10:12.850 They wanted to control the presentation of the video. 00:10:12.850 --> 00:10:17.470 So infants have this apparent craving to explore and feel 00:10:17.470 --> 00:10:20.470 like they have some control over their environment, at an 00:10:20.470 --> 00:10:22.820 age when they don't control a lot because of their limited 00:10:22.820 --> 00:10:25.460 physical capacity. 00:10:25.460 --> 00:10:28.290 In the first three or four months, infants explore the 00:10:28.290 --> 00:10:29.980 world a lot by their mouths. 00:10:29.980 --> 00:10:32.890 That's why people worry to not leave around things that they 00:10:32.890 --> 00:10:36.010 will put into their mouth and swallow, that are dangerous. 00:10:36.010 --> 00:10:38.070 Because their visual and auditory systems, and their 00:10:38.070 --> 00:10:40.460 system with their hand, are slowly developing. 00:10:40.460 --> 00:10:42.540 By five or six months around the world, they start to 00:10:42.540 --> 00:10:44.450 explore with their hands and their eyes around them. 00:10:44.450 --> 00:10:46.580 As their motor system gets more mature. 00:10:46.580 --> 00:10:50.120 As their visual system gains acuity. 00:10:50.120 --> 00:10:53.340 And we already know that infants use social cues to 00:10:53.340 --> 00:10:54.250 guide exploration. 00:10:54.250 --> 00:10:56.660 One of the big changes this happened in the last 10 years, 00:10:56.660 --> 00:11:00.880 I'd say, in infant studies or child studies, has been a lot 00:11:00.880 --> 00:11:04.230 of appreciation about the intersection between cognition 00:11:04.230 --> 00:11:05.590 and social interaction. 00:11:05.590 --> 00:11:07.365 There used to be like two different worlds of people who 00:11:07.365 --> 00:11:08.400 studied language. 00:11:08.400 --> 00:11:10.980 They would have algorithms and formulas about the language. 00:11:10.980 --> 00:11:13.400 And then the social people who'd study how babies were 00:11:13.400 --> 00:11:14.740 cute or something, right? 00:11:14.740 --> 00:11:17.400 But there's been more and more thought that a deep thing in 00:11:17.400 --> 00:11:20.980 us that helps cognition grow, is the social relations that 00:11:20.980 --> 00:11:24.140 an infant is drawn to parents and caretakers. 00:11:24.140 --> 00:11:28.250 So, for example, a six-month-old, if their mother 00:11:28.250 --> 00:11:31.850 rolls or pounds a ball, they tend to copy, they tend to 00:11:31.850 --> 00:11:34.270 imitate that action. 00:11:34.270 --> 00:11:36.180 They follow the eyes of a person. 00:11:36.180 --> 00:11:37.060 Joint attention. 00:11:37.060 --> 00:11:39.210 You know, eyes are the windows on the soul. 00:11:39.210 --> 00:11:40.540 We know eyes mean a lot. 00:11:40.540 --> 00:11:41.860 Where are people putting their attention? 00:11:41.860 --> 00:11:43.380 What are they paying attention to? 00:11:43.380 --> 00:11:45.750 Infants pick up on this very early on. 00:11:45.750 --> 00:11:48.720 And if somebody looks over there they look over there. 00:11:48.720 --> 00:11:50.540 If you look at them they know your attention 00:11:50.540 --> 00:11:52.030 is focused on them. 00:11:52.030 --> 00:11:53.730 And sometimes people will say-- 00:11:53.730 --> 00:11:55.570 because psychologists love to test everything-- is it just 00:11:55.570 --> 00:11:57.100 the way the head is turning? 00:11:57.100 --> 00:11:59.540 So if you cover somebody's head they 00:11:59.540 --> 00:12:00.760 don't follow it anymore. 00:12:00.760 --> 00:12:04.440 They know it has to be the eyes reflecting where the mind 00:12:04.440 --> 00:12:06.010 is putting its attention. 00:12:06.010 --> 00:12:07.230 It's not the head direction. 00:12:07.230 --> 00:12:09.500 It's the eyes. 00:12:09.500 --> 00:12:11.750 Here's something, infants who are a little bit better at 00:12:11.750 --> 00:12:13.200 following eyes-- 00:12:13.200 --> 00:12:14.800 either maturing faster or something-- 00:12:14.800 --> 00:12:16.810 also learn language faster. 00:12:16.810 --> 00:12:19.020 They get words faster, and syntax faster. 00:12:19.020 --> 00:12:22.100 It's as if part of that social interaction is helping to 00:12:22.100 --> 00:12:23.700 drive the language learning. 00:12:23.700 --> 00:12:26.140 So that's how these social things and language things 00:12:26.140 --> 00:12:28.440 interact very substantially. 00:12:28.440 --> 00:12:31.000 And we already said that a 12-month-old will stop at a 00:12:31.000 --> 00:12:33.970 visual cliff, but if the mother smiles there they go. 00:12:33.970 --> 00:12:36.920 So constant learning that mixes in the 00:12:36.920 --> 00:12:39.160 cognitive and the social. 00:12:39.160 --> 00:12:42.506 Now the epic name in developmental psychology is 00:12:42.506 --> 00:12:43.130 Jean Piaget. 00:12:43.130 --> 00:12:46.950 Because prior to him, roughly speaking, in the science of 00:12:46.950 --> 00:12:49.880 child development, people just thought children were sort of 00:12:49.880 --> 00:12:53.460 boring and dumb. 00:12:53.460 --> 00:12:55.310 They need a lot of attention. 00:12:55.310 --> 00:13:00.390 Please finish MIT so we can talk with you intelligently. 00:13:00.390 --> 00:13:02.130 I guess people were not that interested. 00:13:02.130 --> 00:13:04.020 Partly is the world was different in so many ways. 00:13:04.020 --> 00:13:06.130 There was no-- practically no-- 00:13:06.130 --> 00:13:08.280 formal psychology experimentation or thought 00:13:08.280 --> 00:13:11.270 about what really children's mental lives were like. 00:13:11.270 --> 00:13:13.501 And Piaget-- 00:13:13.501 --> 00:13:17.840 I have a wrong year there, 1886-- 00:13:17.840 --> 00:13:19.020 developed-- 00:13:19.020 --> 00:13:21.920 he himself was a child prodigy, trained in biology. 00:13:21.920 --> 00:13:24.430 Very early interest in whether categories are in our heads or 00:13:24.430 --> 00:13:25.540 in the world. 00:13:25.540 --> 00:13:26.260 Tried poetry. 00:13:26.260 --> 00:13:28.070 Worked with Binet on intelligence testing. 00:13:28.070 --> 00:13:30.100 Became interested in patterns of errors and successes. 00:13:30.100 --> 00:13:33.510 You'll see that in many ways, what he discovered about how a 00:13:33.510 --> 00:13:36.150 child mind is different than yours fundamentally, is based 00:13:36.150 --> 00:13:38.470 on the patterns of their errors. 00:13:38.470 --> 00:13:40.590 And he said, there's two basic things going on. 00:13:40.590 --> 00:13:41.980 This is a huge idea. 00:13:41.980 --> 00:13:44.960 One is assimilation, you incorporate new knowledge into 00:13:44.960 --> 00:13:46.270 existing cognitive structures. 00:13:46.270 --> 00:13:48.790 It's basically ways you think about the world. 00:13:48.790 --> 00:13:50.350 And new knowledge is added. 00:13:50.350 --> 00:13:51.660 That's important. 00:13:51.660 --> 00:13:54.140 But he thought the dramatic thing that happens in infancy 00:13:54.140 --> 00:13:56.600 and childhood is what he called adaptation. 00:13:56.600 --> 00:13:58.930 That the fundamental ways in which you understand the world 00:13:58.930 --> 00:14:01.960 are shifted, through development, to accommodate 00:14:01.960 --> 00:14:02.940 new evidence. 00:14:02.940 --> 00:14:04.930 So there's a wonderful book if you come across it called The 00:14:04.930 --> 00:14:06.940 Scientist in the Crib. 00:14:06.940 --> 00:14:08.030 But it's kind of a pun. 00:14:08.030 --> 00:14:09.890 It's written by scientists who study infants. 00:14:09.890 --> 00:14:13.600 But the idea is that, in a sense, every infant is kind of 00:14:13.600 --> 00:14:14.870 his or her own scientist-- 00:14:14.870 --> 00:14:15.720 as you were-- 00:14:15.720 --> 00:14:18.500 probing the world and discovering the physical and 00:14:18.500 --> 00:14:20.390 social laws of the world. 00:14:20.390 --> 00:14:22.530 Because they don't know them coming in and they're going to 00:14:22.530 --> 00:14:23.750 pick up a lot of them. 00:14:23.750 --> 00:14:26.610 They're going to probe them. 00:14:26.610 --> 00:14:30.050 But fail to publish the results. 00:14:30.050 --> 00:14:33.380 So Piaget postulated that were these big stages, what he 00:14:33.380 --> 00:14:36.220 called the Sensorimotor age, zero to two, where the world 00:14:36.220 --> 00:14:38.820 is one of what you see and the physical actions. 00:14:38.820 --> 00:14:40.920 And there's not much representation of ideas or 00:14:40.920 --> 00:14:41.810 lasting thoughts. 00:14:41.810 --> 00:14:43.960 And we'll see some examples of these. 00:14:43.960 --> 00:14:45.950 Between two and seven, you start to be able to keep a 00:14:45.950 --> 00:14:47.160 thought in your mind. 00:14:47.160 --> 00:14:48.840 You still have an egocentric prospective. 00:14:48.840 --> 00:14:51.720 You see the world from your view but not appreciating the 00:14:51.720 --> 00:14:53.770 views of somebody else. 00:14:53.770 --> 00:14:55.800 You start to use language. 00:14:55.800 --> 00:14:59.430 A lot of flimsy discussion about fantasy and reality. 00:14:59.430 --> 00:15:01.340 I could tell you with my own daughter, who you'll meet, 00:15:01.340 --> 00:15:02.660 she's still working out whether fairies 00:15:02.660 --> 00:15:05.530 really exist or not. 00:15:05.530 --> 00:15:07.700 This was chaotic because we went to some skating show 00:15:07.700 --> 00:15:11.720 where Tinkerbell was a human dancing, and that totally made 00:15:11.720 --> 00:15:12.970 the situation very complicated. 00:15:15.430 --> 00:15:16.680 She's still working on that. 00:15:16.680 --> 00:15:20.920 Concrete, as you get 7 to 11, organize logical thought. 00:15:20.920 --> 00:15:23.420 Still concrete, as opposed to sort of abstract. 00:15:23.420 --> 00:15:26.080 And then you move to more adult like cognition, which 00:15:26.080 --> 00:15:28.270 we'll talk about next week. 00:15:28.270 --> 00:15:33.060 So the idea is from birth to two years, you would love to 00:15:33.060 --> 00:15:35.830 have an infant just tell you what do I think the world is 00:15:35.830 --> 00:15:36.360 really like. 00:15:36.360 --> 00:15:38.800 They have very modest language, of course, so they 00:15:38.800 --> 00:15:40.390 can't tell you what they see. 00:15:40.390 --> 00:15:43.630 So the thought is they have fleeting, disconnected sensory 00:15:43.630 --> 00:15:45.030 impressions and motor reactions. 00:15:45.030 --> 00:15:46.270 It's all, what do I see? 00:15:46.270 --> 00:15:48.160 How am I responding? 00:15:48.160 --> 00:15:52.500 That their focus of thought is centered on actions, not 00:15:52.500 --> 00:15:53.990 things or intentions. 00:15:53.990 --> 00:15:56.190 And I'll show you in a very concrete way. 00:15:56.190 --> 00:15:58.170 That there's no distinction in their mind between things that 00:15:58.170 --> 00:16:00.680 are stable in the world and transient events. 00:16:00.680 --> 00:16:03.620 No distinction between themselves and the world 00:16:03.620 --> 00:16:04.140 around them. 00:16:04.140 --> 00:16:09.150 It's all just one big mush until they connect abstract 00:16:09.150 --> 00:16:12.650 representations that separate these things out. 00:16:12.650 --> 00:16:18.700 So let's talk about object permanence. 00:16:18.700 --> 00:16:22.160 I'm going to show you that you have object permanence just by 00:16:22.160 --> 00:16:23.940 saying, here's my pointer. 00:16:23.940 --> 00:16:24.650 I need a volunteer. 00:16:24.650 --> 00:16:31.260 This is so easy that you will not feel scared. 00:16:31.260 --> 00:16:34.200 I promise. 00:16:34.200 --> 00:16:34.410 All right. 00:16:34.410 --> 00:16:35.320 Thank you very much. 00:16:35.320 --> 00:16:37.880 So you see this? 00:16:37.880 --> 00:16:39.950 Where do you think it is now? 00:16:39.950 --> 00:16:41.120 OK. 00:16:41.120 --> 00:16:42.740 If I was really cool teacher who did 00:16:42.740 --> 00:16:45.690 magic it would be gone. 00:16:45.690 --> 00:16:46.870 But yes, and you know it's there. 00:16:46.870 --> 00:16:49.070 That's object permanence. 00:16:49.070 --> 00:16:50.630 If you turn your head you believe it's 00:16:50.630 --> 00:16:52.540 probably still there. 00:16:52.540 --> 00:16:56.900 But that's going beyond the fundamentals of perception, 00:16:56.900 --> 00:16:58.820 that's your knowledge, and representing in your head, 00:16:58.820 --> 00:17:01.350 there's something I don't see but I know it's there. 00:17:01.350 --> 00:17:04.980 That is not available to a zero to two year old. 00:17:04.980 --> 00:17:09.660 So, for example, if they see a rattle they feel a rattle. 00:17:09.660 --> 00:17:12.640 But now if they look away, or if you just put a sheet of 00:17:12.640 --> 00:17:13.420 paper in front of it-- 00:17:13.420 --> 00:17:15.339 I'll show you a couple of examples-- 00:17:15.339 --> 00:17:19.109 they behave as if the rattle no longer exists. 00:17:19.109 --> 00:17:20.520 Just like I did in front of you. 00:17:20.520 --> 00:17:23.510 If you just cover it up, it's gone as if it doesn't exist. 00:17:23.510 --> 00:17:26.579 Because their mind cannot represent what they do not see 00:17:26.579 --> 00:17:28.960 right in front of them. 00:17:28.960 --> 00:17:32.200 So out of sight out of existence. 00:17:32.200 --> 00:17:34.660 So you can show them a toy they love, and until about 00:17:34.660 --> 00:17:37.590 eight months, you could do this. 00:17:37.590 --> 00:17:38.480 They'll start crying. 00:17:38.480 --> 00:17:40.020 They'll protest. 00:17:40.020 --> 00:17:42.650 But they won't reach for it, even when it's easily within 00:17:42.650 --> 00:17:43.610 their reach. 00:17:43.610 --> 00:17:44.730 Out of sight, out of mind. 00:17:44.730 --> 00:17:45.330 It doesn't exist. 00:17:45.330 --> 00:17:50.560 They can't represent in their mind what they don't see. 00:17:50.560 --> 00:17:51.590 And then there's another one. 00:17:51.590 --> 00:17:52.990 You'll see a film of this. 00:17:52.990 --> 00:17:53.920 But let me tell you this. 00:17:53.920 --> 00:17:58.180 Which tells you about actions verses other things. 00:17:58.180 --> 00:18:01.400 So imagine you hide a toy under one location, the child 00:18:01.400 --> 00:18:02.720 searches there, finds it. 00:18:02.720 --> 00:18:04.090 You hide it again in the same location. 00:18:04.090 --> 00:18:05.520 You encourage the child to search. 00:18:05.520 --> 00:18:06.050 They find it. 00:18:06.050 --> 00:18:08.450 They do it two or three times. 00:18:08.450 --> 00:18:12.130 Now, in front of the child, you take that same object that 00:18:12.130 --> 00:18:13.590 you've shown them like this several times. 00:18:13.590 --> 00:18:15.280 They've grabbed several times. 00:18:15.280 --> 00:18:17.780 And you simply, in front of them, pick it up 00:18:17.780 --> 00:18:19.070 and put it over here. 00:18:19.070 --> 00:18:20.510 And they're viewing everything in full view, 00:18:20.510 --> 00:18:22.240 just like you did. 00:18:22.240 --> 00:18:23.810 What do they do? 00:18:23.810 --> 00:18:26.990 When it's their turn to grab they grab here. 00:18:26.990 --> 00:18:27.790 The wrong place. 00:18:27.790 --> 00:18:29.920 The place where they grab before. 00:18:29.920 --> 00:18:33.650 Because what's in their mind is the action they did. 00:18:33.650 --> 00:18:36.250 Not the object as an independent thing they can put 00:18:36.250 --> 00:18:36.670 in their mind. 00:18:36.670 --> 00:18:37.690 Does that makes sense? 00:18:37.690 --> 00:18:40.320 And I'll show you several pieces of this. 00:18:40.320 --> 00:18:42.120 It's called the A-not-B effect. 00:18:42.120 --> 00:18:46.440 I put this A, A, A, A in the front, full view. 00:18:46.440 --> 00:18:50.920 Put it over here and they reach over here to get it. 00:18:50.920 --> 00:18:56.360 So this is this idea, that in their head is not a toy. 00:18:56.360 --> 00:18:58.910 Their head is representing the thing on the right that they 00:18:58.910 --> 00:18:59.460 reached for. 00:18:59.460 --> 00:19:01.450 Because they don't represent ideas of things. 00:19:01.450 --> 00:19:05.610 They represent actions that they've done. 00:19:05.610 --> 00:19:07.220 So here's object permanence. 00:19:07.220 --> 00:19:10.650 Here's a child sees a toy they like. 00:19:10.650 --> 00:19:13.616 You put up, in front of them, this thing and tragically, 00:19:13.616 --> 00:19:15.640 it's disappeared. 00:19:15.640 --> 00:19:17.190 It's gone out of existence in the world. 00:19:21.740 --> 00:19:24.020 Some people have done some sort of NIRS imaging 00:19:24.020 --> 00:19:27.990 suggesting that kids who get past this stage are developing 00:19:27.990 --> 00:19:29.950 some frontal maturation. 00:19:29.950 --> 00:19:31.660 But I think the most compelling things are the 00:19:31.660 --> 00:19:32.910 videos of the kids themselves. 00:19:38.450 --> 00:19:41.530 So let me show you another film, again very cleverly, the 00:19:41.530 --> 00:19:43.880 Renee Baillergon has been one the leaders in this field-- 00:19:43.880 --> 00:19:51.520 very cleverly showing you what infants grasp and don't grasp. 00:19:51.520 --> 00:19:54.360 Not only the brilliance of these experiments. 00:19:54.360 --> 00:19:56.320 These infants are really trying to figure out the 00:19:56.320 --> 00:19:58.990 world, and coming up with hypotheses that they're 00:19:58.990 --> 00:19:59.580 confirming. 00:19:59.580 --> 00:20:02.100 And then when they're broken down they're upset with 00:20:02.100 --> 00:20:03.130 what's going on. 00:20:03.130 --> 00:20:05.890 So let's move on to age two to seven, especially in the early 00:20:05.890 --> 00:20:09.160 years, so-called a preoperational stage. 00:20:09.160 --> 00:20:12.100 And one of the coolest things, and we'll try this and see how 00:20:12.100 --> 00:20:16.320 it goes with some girls in a few minutes, is this idea. 00:20:16.320 --> 00:20:19.130 So if you see two glasses filled with equal amounts of 00:20:19.130 --> 00:20:23.070 liquid, and you pour one over into the thinner, taller 00:20:23.070 --> 00:20:27.720 glass, c, which will have more water in it? 00:20:27.720 --> 00:20:29.930 A or C? 00:20:29.930 --> 00:20:31.180 The same. 00:20:33.460 --> 00:20:36.650 But not if you're a two year old or a four-year-old. 00:20:36.650 --> 00:20:38.700 So it's called conservation of liquid. 00:20:45.840 --> 00:20:48.230 So, it's kind of fascinating, isn't it? 00:20:48.230 --> 00:20:50.190 It's kind of amazing. 00:20:50.190 --> 00:20:52.000 If you do this with a three year old it's virtually 00:20:52.000 --> 00:20:53.210 guaranteed they'll do this. 00:20:53.210 --> 00:20:55.403 All of you did it all over the world. 00:20:55.403 --> 00:20:57.935 And, in some sense, as far as we can guess , all throughout 00:20:57.935 --> 00:20:59.220 our species' history. 00:20:59.220 --> 00:21:02.660 So brilliant ways of showing that babies, or young 00:21:02.660 --> 00:21:06.990 children, really see a little bit of a different world than 00:21:06.990 --> 00:21:11.940 you and I as adults. 00:21:11.940 --> 00:21:16.080 So here's another very powerful area of research, 00:21:16.080 --> 00:21:20.650 which is taking perspectives from the view that other 00:21:20.650 --> 00:21:22.810 people have thoughts and feelings besides yourself and 00:21:22.810 --> 00:21:24.060 how you interact with them. 00:21:26.330 --> 00:21:28.260 And people call this idea theory of mind. 00:21:28.260 --> 00:21:32.030 The idea that you understand that other people out there 00:21:32.030 --> 00:21:35.360 have their own thoughts, their own feelings distinct from 00:21:35.360 --> 00:21:39.040 yours, and in the most challenging case, they can 00:21:39.040 --> 00:21:40.990 even be false beliefs. 00:21:40.990 --> 00:21:43.580 A person can have wrong information in their head and 00:21:43.580 --> 00:21:46.370 truly believe it, even when you know it's wrong. 00:21:46.370 --> 00:21:48.520 Because you, as an adult, realize that thoughts are one 00:21:48.520 --> 00:21:51.320 thing and physical reality is another thing. 00:21:51.320 --> 00:21:52.700 But that's not what children think. 00:21:52.700 --> 00:21:55.540 They think there's just one reality. 00:21:55.540 --> 00:21:57.670 That's why at the very youngest age, they think if 00:21:57.670 --> 00:22:01.970 they cover their eyes that you don't know where they are,. 00:22:01.970 --> 00:22:04.220 Because they think there's one physical reality only. 00:22:04.220 --> 00:22:06.500 And they don't realize there's another prospective 00:22:06.500 --> 00:22:08.080 besides their own. 00:22:08.080 --> 00:22:11.250 So here's a very clever experiment showing you that at 00:22:11.250 --> 00:22:15.090 three months, children code the word in terms of actions. 00:22:15.090 --> 00:22:18.010 And by six to nine months, they begin to understand 00:22:18.010 --> 00:22:21.320 intentions, that people out there-- animals too but we'll 00:22:21.320 --> 00:22:23.550 just focus on people-- have intentions and 00:22:23.550 --> 00:22:25.140 goals in their head. 00:22:25.140 --> 00:22:26.900 So here's what the experiment they do using this 00:22:26.900 --> 00:22:28.580 habituation. 00:22:28.580 --> 00:22:32.460 There's two pedestals here, and a person reaches again and 00:22:32.460 --> 00:22:34.960 again for a ball. 00:22:34.960 --> 00:22:40.190 So now, what do you believe the intention is? 00:22:40.190 --> 00:22:41.630 To reach for the ball. 00:22:41.630 --> 00:22:43.790 You see it 10 times, the baby's losing interest. 00:22:43.790 --> 00:22:47.470 Now comes their shocker to get the baby crying, or laughing, 00:22:47.470 --> 00:22:48.180 or drooling. 00:22:48.180 --> 00:22:49.410 Get the baby's attention that you can 00:22:49.410 --> 00:22:51.380 measure by how they respond. 00:22:51.380 --> 00:22:54.950 And in some conditions, something goes down, and when 00:22:54.950 --> 00:22:56.460 it goes back up the person reaches. 00:22:56.460 --> 00:22:59.240 But now they take the same action. 00:22:59.240 --> 00:23:01.950 They reach for the left pedestal, but 00:23:01.950 --> 00:23:03.580 it's a teddy bear. 00:23:03.580 --> 00:23:06.380 Or another case, they reach for the ball in 00:23:06.380 --> 00:23:08.240 the opposite side. 00:23:08.240 --> 00:23:11.780 Who, depending on their age, sees these two different 00:23:11.780 --> 00:23:15.300 changes in the scenario as startling? 00:23:15.300 --> 00:23:18.750 The three month olds are startled when the person 00:23:18.750 --> 00:23:23.150 reaches for the same object. 00:23:23.150 --> 00:23:24.350 The three month old. 00:23:24.350 --> 00:23:27.270 Because in their mind, the only thing that was really 00:23:27.270 --> 00:23:29.960 happening was reach for the left, reach for the left, 00:23:29.960 --> 00:23:30.620 reach for the left. 00:23:30.620 --> 00:23:32.030 And now you're reaching for the right. 00:23:32.030 --> 00:23:34.050 The action changed. 00:23:34.050 --> 00:23:36.010 Because the action is independent of intention. 00:23:36.010 --> 00:23:38.060 It's just what happened, what happened, what happened. 00:23:38.060 --> 00:23:40.080 They're shocked when the person goes for 00:23:40.080 --> 00:23:41.510 the ball over here. 00:23:41.510 --> 00:23:43.810 By six to nine months, they're shocked-- 00:23:43.810 --> 00:23:45.000 relatively speaking-- 00:23:45.000 --> 00:23:48.060 when the person reaches for the same action but now the 00:23:48.060 --> 00:23:49.260 goal is different. 00:23:49.260 --> 00:23:50.660 Grabbing the teddy bear. 00:23:50.660 --> 00:23:53.080 It's as if they understand the intention of the person was to 00:23:53.080 --> 00:23:55.710 get the ball, and these children think the only thing 00:23:55.710 --> 00:23:57.870 that's happening is physical action, physical action, 00:23:57.870 --> 00:23:58.890 physical action. 00:23:58.890 --> 00:24:01.950 So very clever experiment by this habituation and looking 00:24:01.950 --> 00:24:05.660 time to show at three months all you see is actions. 00:24:05.660 --> 00:24:09.260 And by six to nine months you start to grasp that people 00:24:09.260 --> 00:24:12.360 have intentions in their head above and beyond their actions 00:24:12.360 --> 00:24:14.700 that govern their actions. 00:24:14.700 --> 00:24:18.020 So to make it really tricky, there's this very clever 00:24:18.020 --> 00:24:20.460 experiment that makes-- 00:24:20.460 --> 00:24:22.150 and we'll try it in a few minutes-- 00:24:22.150 --> 00:24:22.550 this way. 00:24:22.550 --> 00:24:24.950 This so-called Sally-Anne problem because it's been so 00:24:24.950 --> 00:24:26.760 widely cited and discussed. 00:24:26.760 --> 00:24:28.880 So you tell a child this story. 00:24:28.880 --> 00:24:31.210 Imagine there's two girls here, Sally and Anne. 00:24:31.210 --> 00:24:35.300 And Sally takes a ball and puts it in this basket. 00:24:35.300 --> 00:24:37.570 And then she leaves the room. 00:24:37.570 --> 00:24:40.910 Anne, who's a little bit of a troublemaker takes the ball 00:24:40.910 --> 00:24:44.730 out of here and puts it into this box, and closes the box. 00:24:44.730 --> 00:24:47.100 Here's the big question. 00:24:47.100 --> 00:24:50.030 When Sally comes back and looks for this ball, where 00:24:50.030 --> 00:24:51.060 will she look? 00:24:51.060 --> 00:24:53.860 And a three year old says, in the box. 00:24:53.860 --> 00:24:56.770 Now if she was out of the room there's no way for her to look 00:24:56.770 --> 00:24:57.500 that's in the box. 00:24:57.500 --> 00:24:59.750 But for the three year old, there's not 00:24:59.750 --> 00:25:01.090 thoughts and reality. 00:25:01.090 --> 00:25:03.220 There's just kind of reality. 00:25:03.220 --> 00:25:04.520 Does that make sense? 00:25:04.520 --> 00:25:07.410 The three year old can't entertain the idea that Sally 00:25:07.410 --> 00:25:10.770 has, in her head, wrong knowledge of 00:25:10.770 --> 00:25:11.580 where this ball is. 00:25:11.580 --> 00:25:13.370 The she couldn't have known where it is and she's going to 00:25:13.370 --> 00:25:15.070 act on the knowledge that's in her head. 00:25:15.070 --> 00:25:17.300 That's the content of her mind. 00:25:17.300 --> 00:25:19.395 The three year old says there's one reality, the ball 00:25:19.395 --> 00:25:20.420 is over here. 00:25:20.420 --> 00:25:21.280 I know it. 00:25:21.280 --> 00:25:22.160 Everybody knows it. 00:25:22.160 --> 00:25:25.170 What else is there to even think about? 00:25:25.170 --> 00:25:28.740 But that typical five-year-old will say, Sally will look in 00:25:28.740 --> 00:25:29.870 the wrong place. 00:25:29.870 --> 00:25:31.840 She'll look in the basket. 00:25:31.840 --> 00:25:33.810 She'll look in the wrong place compared to 00:25:33.810 --> 00:25:34.650 where the ball is now. 00:25:34.650 --> 00:25:35.870 Because she believes it's there. 00:25:35.870 --> 00:25:37.390 She has the wrong idea in her head. 00:25:37.390 --> 00:25:40.970 That ideas can be independent of physical, observable things 00:25:40.970 --> 00:25:43.590 in the world. 00:25:43.590 --> 00:25:44.870 This is a universal finding. 00:25:44.870 --> 00:25:46.050 I'm going to have to change my settings. 00:25:46.050 --> 00:25:46.670 Sorry. 00:25:46.670 --> 00:25:48.620 Your handout has this. 00:25:48.620 --> 00:25:50.540 In practically every country where they've tested this, 00:25:50.540 --> 00:25:52.150 three year olds don't have a theory of mind, 00:25:52.150 --> 00:25:54.760 five year olds do. 00:25:54.760 --> 00:25:55.660 Turns out-- 00:25:55.660 --> 00:25:57.420 and you could take a guess-- 00:25:57.420 --> 00:26:02.020 the older sibling you have, the younger you become at 00:26:02.020 --> 00:26:04.420 getting a good theory of mind. 00:26:04.420 --> 00:26:08.840 Nobody really knows what the answer but what's your guess? 00:26:08.840 --> 00:26:10.480 The more siblings you have that are older 00:26:10.480 --> 00:26:12.540 than you, the younger-- 00:26:12.540 --> 00:26:15.090 by some number of months-- people tend to show that they 00:26:15.090 --> 00:26:17.290 can understand that people have all kinds of thoughts and 00:26:17.290 --> 00:26:19.150 beliefs in their head. 00:26:19.150 --> 00:26:20.290 What's your guess? 00:26:20.290 --> 00:26:21.180 Yeah. 00:26:21.180 --> 00:26:23.340 AUDIENCE: They have gone through versions of the 00:26:23.340 --> 00:26:25.020 Sally-Anne problem themselves. 00:26:25.020 --> 00:26:26.980 PROFESSOR: They may have been tortured by their siblings. 00:26:26.980 --> 00:26:29.070 But on top of that, the intuition is-- and we don't 00:26:29.070 --> 00:26:31.160 really know, this is hard to-- 00:26:31.160 --> 00:26:33.210 they're living in a world, because they have older 00:26:33.210 --> 00:26:35.910 siblings who do unkind things to them, who have superior 00:26:35.910 --> 00:26:40.880 powers over them physically, they're much more socially-- 00:26:40.880 --> 00:26:42.800 have to figure out what's going on to survive happily 00:26:42.800 --> 00:26:45.330 and make their way in the world. 00:26:45.330 --> 00:26:48.781 The big five year old, he or she is dominant, and the two 00:26:48.781 --> 00:26:50.530 year old is trying to steer around. 00:26:50.530 --> 00:26:51.910 Like, what is does that five year old think? 00:26:51.910 --> 00:26:53.330 How will I not get into trouble with that 00:26:53.330 --> 00:26:56.080 five-year-old and my mother and my father? 00:26:56.080 --> 00:27:00.430 A younger sibling has more social pressures to figure out 00:27:00.430 --> 00:27:02.430 what's going on and steer your way around, and not get in 00:27:02.430 --> 00:27:05.520 trouble with your older siblings. 00:27:05.520 --> 00:27:06.400 We'll come back to autism. 00:27:06.400 --> 00:27:08.700 I'll just say a word about this now. 00:27:08.700 --> 00:27:10.480 You hear a lot about it. 00:27:10.480 --> 00:27:13.050 The current guess is that it's approximately 1 out of every 00:27:13.050 --> 00:27:14.070 140 children. 00:27:14.070 --> 00:27:16.060 A shockinging increase in numbers to what people 00:27:16.060 --> 00:27:19.160 believed it was many years ago. 00:27:19.160 --> 00:27:21.440 Mysteriously, there's many more boys 00:27:21.440 --> 00:27:23.240 than girls with autism. 00:27:23.240 --> 00:27:25.790 Estimates are 4 to 1, or 10 to 1 range, all there. 00:27:25.790 --> 00:27:27.650 It's hard to know for sure. 00:27:27.650 --> 00:27:29.220 We'll talk more about that. 00:27:29.220 --> 00:27:31.830 Autism is defined by three things. 00:27:31.830 --> 00:27:33.700 A sort of weakness, or deficit, in social 00:27:33.700 --> 00:27:35.470 interaction. 00:27:35.470 --> 00:27:37.850 Children with autism, or adults, have difficulty in 00:27:37.850 --> 00:27:39.270 social interaction. 00:27:39.270 --> 00:27:40.220 In communication. 00:27:40.220 --> 00:27:43.030 And they have lots of repetitive behaviors that can 00:27:43.030 --> 00:27:46.630 be difficult to help in interaction with others. 00:27:46.630 --> 00:27:50.130 And when people test theory of mind in children with autism, 00:27:50.130 --> 00:27:53.410 it's typically delayed by five or six years on average, for 00:27:53.410 --> 00:27:55.420 those children who can take the test at all. 00:27:55.420 --> 00:27:59.470 They have a very slowly developing, very delayed 00:27:59.470 --> 00:28:01.450 theory of mind and understanding what's in the 00:28:01.450 --> 00:28:04.260 content of the thoughts of other people. 00:28:04.260 --> 00:28:06.990 And that's considered one of their biggest challenges. 00:28:06.990 --> 00:28:08.190 How they relate to other people. 00:28:08.190 --> 00:28:10.360 Understanding what the other person's thinking and feeling. 00:28:15.470 --> 00:28:17.080 Just for a couple minutes I'm going to show you a video and 00:28:17.080 --> 00:28:18.330 then we're going to try-- 00:28:18.330 --> 00:28:23.590 So the biggest challenges to Piaget have been this idea 00:28:23.590 --> 00:28:26.540 that there's these distinct stages of thought. 00:28:26.540 --> 00:28:28.410 That your mind shifts, literally, how it's 00:28:28.410 --> 00:28:30.570 constructed and understands the world. 00:28:30.570 --> 00:28:33.270 And that people have thought that the process is much more 00:28:33.270 --> 00:28:36.300 continuous than Piaget had suggested. 00:28:36.300 --> 00:28:39.260 And here's one compelling example of that kind. 00:28:39.260 --> 00:28:41.670 So this is the A-not-B experiment. 00:28:41.670 --> 00:28:43.490 There's a two food wells, and something of 00:28:43.490 --> 00:28:44.540 interest in this infant. 00:28:44.540 --> 00:28:48.170 The seven month old looks at the toy here. 00:28:48.170 --> 00:28:49.420 It gets covered up. 00:28:53.110 --> 00:28:56.500 It's placed in b, and b is one of the two wells. 00:28:56.500 --> 00:28:58.990 He continues to look at b when both are covered. 00:28:58.990 --> 00:29:01.090 He knows the toy is over there. 00:29:01.090 --> 00:29:04.610 And the toy has been placed over and over again in a. 00:29:04.610 --> 00:29:06.040 So he gets the A-not-B error. 00:29:06.040 --> 00:29:07.750 He has the action. 00:29:07.750 --> 00:29:10.170 And even though he sees the toy is placed there. 00:29:10.170 --> 00:29:11.050 It's covered up. 00:29:11.050 --> 00:29:13.550 He's looking where the toy is. 00:29:13.550 --> 00:29:16.750 When it's time to reach he goes to this well. 00:29:16.750 --> 00:29:18.510 So this is A-not-B error. 00:29:18.510 --> 00:29:25.360 A part of his mind that guides action is stuck and guides 00:29:25.360 --> 00:29:27.740 what he reaches for. 00:29:27.740 --> 00:29:30.850 But obviously another part of his mind knows perfectly well 00:29:30.850 --> 00:29:32.320 where the toy is. 00:29:32.320 --> 00:29:36.180 So it's not as if it's all of one, or all of another. 00:29:36.180 --> 00:29:39.910 His mind is representing that there's a toy down there, but 00:29:39.910 --> 00:29:42.580 the part of his brain or mind that guides his action is 00:29:42.580 --> 00:29:44.760 still stuck at this early developmental stage. it's if 00:29:44.760 --> 00:29:46.190 he were two ages. 00:29:46.190 --> 00:29:48.370 One guiding where his eyes goes. 00:29:48.370 --> 00:29:50.070 And one guiding the ultimate action of 00:29:50.070 --> 00:29:51.340 where his hands goes. 00:29:51.340 --> 00:29:53.960 And as he gets a little older, his eyes and hands will go in 00:29:53.960 --> 00:29:56.390 the same place. 00:29:56.390 --> 00:29:59.650 OK, last couple of things about how infants are 00:29:59.650 --> 00:30:01.300 mathematicians. 00:30:01.300 --> 00:30:04.030 Because, of course, we focused on language, or social 00:30:04.030 --> 00:30:07.790 thought, but the ideas of counting and, ultimately, 00:30:07.790 --> 00:30:11.990 arithmetic or math also come out of children's minds. 00:30:11.990 --> 00:30:13.450 And a very clever experiment-- 00:30:13.450 --> 00:30:14.640 and I'll show you two of them-- 00:30:14.640 --> 00:30:17.840 that shows even at six months, infants are starting to 00:30:17.840 --> 00:30:20.130 prepare themselves to become mathematicians. 00:30:20.130 --> 00:30:22.010 And here's how they begin the counting. 00:30:22.010 --> 00:30:25.480 They're shown displays of three objects or two objects. 00:30:25.480 --> 00:30:28.000 And then they hear two sounds like boom boom. 00:30:28.000 --> 00:30:29.450 And where do they look? 00:30:29.450 --> 00:30:31.560 They tend to look at the one with two objects. 00:30:31.560 --> 00:30:32.830 So this is pretty impressive. 00:30:32.830 --> 00:30:34.260 They're counting the two. 00:30:34.260 --> 00:30:37.340 They're relating something in sound to something in sight 00:30:37.340 --> 00:30:40.050 that's arbitrarily related, but that shares the 00:30:40.050 --> 00:30:41.690 numerosity. 00:30:41.690 --> 00:30:45.030 And if they get boom, boom, boom, three boom sounds, then 00:30:45.030 --> 00:30:48.680 they go, OK, now I like the display with three things. 00:30:48.680 --> 00:30:52.550 They understand, in some level, twoness and threeness. 00:30:52.550 --> 00:30:57.880 And so you start to have the basis of having numbers. 00:30:57.880 --> 00:30:59.820 And not only that, Karen Wynn at Yale has shown quite 00:30:59.820 --> 00:31:02.300 cleverly, not only do infants have numbers. 00:31:02.300 --> 00:31:05.530 They can do a little bit of subtraction and addition. 00:31:05.530 --> 00:31:07.190 So here's the experiment she does. 00:31:07.190 --> 00:31:08.990 She places an object in a case. 00:31:08.990 --> 00:31:10.500 The screen comes up. 00:31:10.500 --> 00:31:12.370 Now comes the second object. 00:31:12.370 --> 00:31:13.670 And the hand leaves. 00:31:13.670 --> 00:31:14.930 OK. 00:31:14.930 --> 00:31:15.880 The screen drops. 00:31:15.880 --> 00:31:16.680 And there are two. 00:31:16.680 --> 00:31:19.120 One plus one equals two. 00:31:19.120 --> 00:31:21.520 And the infant goes, OK, no big deal. 00:31:21.520 --> 00:31:24.970 But if the screen drops and there's one, the infant is 00:31:24.970 --> 00:31:26.790 startled and looks longer. 00:31:26.790 --> 00:31:28.130 And they can do it the other way around. 00:31:28.130 --> 00:31:30.430 They can do subtraction as well. 00:31:30.430 --> 00:31:33.920 So one plus one equals two, and if there's one left by the 00:31:33.920 --> 00:31:36.080 trickery of the kind you saw earlier, they're disturbed 00:31:36.080 --> 00:31:38.330 that the addition has not occurred correctly. 00:31:38.330 --> 00:31:41.290 Or the subtraction has not occurred correctly. 00:31:41.290 --> 00:31:45.210 And there's kind of a debate-- this is the last slide-- 00:31:45.210 --> 00:31:48.800 and here's the core idea, though, which is this. 00:31:48.800 --> 00:31:52.840 That our minds afford us, by evolution, counting up to 00:31:52.840 --> 00:31:54.690 about four objects in the world. 00:31:54.690 --> 00:31:56.990 And many animals do that as well. 00:31:56.990 --> 00:32:00.060 That sort of has to develop a little bit, but we've at lot 00:32:00.060 --> 00:32:01.570 running in us. 00:32:01.570 --> 00:32:02.970 So that infants can do. 00:32:02.970 --> 00:32:06.020 Because, of course, if you show 7-- if you give 77 booms, 00:32:06.020 --> 00:32:09.540 they don't look for the display with 77 versus 78. 00:32:09.540 --> 00:32:11.030 They can't do that. 00:32:11.030 --> 00:32:14.550 So they can operate in the world of 1 to 3 or 1 to 4. 00:32:14.550 --> 00:32:15.790 And then they discovered-- 00:32:15.790 --> 00:32:19.350 there's been a series of studies in tribes, that are 00:32:19.350 --> 00:32:22.060 relatively isolated in different parts of the world, 00:32:22.060 --> 00:32:25.290 where in their language they only have words for 00:32:25.290 --> 00:32:26.950 one, two, and three. 00:32:26.950 --> 00:32:29.050 And everything after that is really described as 00:32:29.050 --> 00:32:30.680 many, or a whole lot. 00:32:30.680 --> 00:32:33.155 They don't have words for five and up. 00:32:33.155 --> 00:32:35.630 There's no word in their language. 00:32:35.630 --> 00:32:38.170 Because they've never needed it, apparently, in the worlds 00:32:38.170 --> 00:32:39.240 they live in. 00:32:39.240 --> 00:32:41.140 So they go to them and they have them do 00:32:41.140 --> 00:32:43.150 little counting tasks. 00:32:43.150 --> 00:32:46.130 And as soon as they get beyond about four they get very 00:32:46.130 --> 00:32:47.930 inaccurate. 00:32:47.930 --> 00:32:51.340 It's as if the mind naturally can represent about four 00:32:51.340 --> 00:32:54.660 things in the object world, four things in the counting 00:32:54.660 --> 00:32:56.420 world-- maybe because of that-- 00:32:56.420 --> 00:32:59.920 and after that everything is a cultural invention of higher 00:32:59.920 --> 00:33:01.200 level mathematics. 00:33:01.200 --> 00:33:03.020 It builds off one to four. 00:33:03.020 --> 00:33:04.830 But you don't have it unless your culture 00:33:04.830 --> 00:33:06.030 teaches it to you. 00:33:06.030 --> 00:33:09.250 Or your culture invents it. 00:33:09.250 --> 00:33:11.460 And there's been brain imaging studies too, suggesting that 00:33:11.460 --> 00:33:14.570 counting one to four is very different in the brain than 00:33:14.570 --> 00:33:17.330 exact mathematics beyond the number four or five. 00:33:17.330 --> 00:33:20.940 That's all culturally learned and invented. 00:33:20.940 --> 00:33:23.180 It's based on an innate one to four capacity.