0:00:16.524,0:00:19.207 I want you to take a look at this baby. 0:00:19.679,0:00:24.475 What you're drawn to are her eyes[br]and the skin you love to touch. 0:00:24.886,0:00:28.026 But today I'm going to talk to you[br]about something you can't see. 0:00:28.050,0:00:30.802 What's going on[br]up in that little brain of hers. 0:00:31.635,0:00:35.556 The modern tools of neuroscience[br]are demonstrating to us 0:00:35.580,0:00:39.475 that what's going on up there[br]is nothing short of rocket science. 0:00:40.236,0:00:43.673 And what we're learning[br]is going to shed some light 0:00:43.697,0:00:49.595 on what the romantic writers and poets[br]described as the "celestial openness" 0:00:49.619,0:00:51.476 of the child's mind. 0:00:52.513,0:00:55.971 What we see here is a mother in India, 0:00:55.995,0:00:59.899 and she's speaking Koro,[br]which is a newly discovered language. 0:01:00.297,0:01:02.104 And she's talking to her baby. 0:01:02.589,0:01:03.745 What this mother -- 0:01:03.769,0:01:06.988 and the 800 people who speak[br]Koro in the world -- 0:01:07.012,0:01:10.222 understands is that,[br]to preserve this language, 0:01:10.246,0:01:12.832 they need to speak it to the babies. 0:01:12.856,0:01:15.731 And therein lies a critical puzzle. 0:01:15.755,0:01:18.005 Why is it that you can't[br]preserve a language 0:01:18.029,0:01:21.264 by speaking to you and I, to the adults? 0:01:21.288,0:01:23.476 Well, it's got to do with your brain. 0:01:24.038,0:01:28.476 What we see here is that language[br]has a critical period for learning. 0:01:28.900,0:01:32.700 The way to read this slide is to look[br]at your age on the horizontal axis. 0:01:32.724,0:01:35.407 (Laughter) 0:01:35.431,0:01:39.070 And you'll see on the vertical[br]your skill at acquiring a second language. 0:01:39.689,0:01:43.548 The babies and children are geniuses[br]until they turn seven, 0:01:43.572,0:01:45.876 and then there's a systematic decline. 0:01:45.900,0:01:48.397 After puberty, we fall off the map. 0:01:48.834,0:01:51.366 No scientists dispute this curve, 0:01:51.390,0:01:53.345 but laboratories all over the world 0:01:53.369,0:01:55.876 are trying to figure out[br]why it works this way. 0:01:56.418,0:02:00.452 Work in my lab is focused on the first[br]critical period in development, 0:02:00.476,0:02:02.321 and that is the period in which babies 0:02:02.345,0:02:05.710 try to master which sounds[br]are used in their language. 0:02:05.734,0:02:08.223 We think, by studying[br]how the sounds are learned, 0:02:08.247,0:02:10.513 we'll have a model[br]for the rest of language, 0:02:10.537,0:02:13.475 and perhaps for critical periods[br]that may exist in childhood 0:02:13.499,0:02:16.362 for social, emotional[br]and cognitive development. 0:02:16.935,0:02:18.876 So we've been studying the babies 0:02:18.900,0:02:21.403 using a technique[br]that we're using all over the world 0:02:21.427,0:02:23.283 and the sounds of all languages. 0:02:23.307,0:02:25.098 The baby sits on a parent's lap, 0:02:25.122,0:02:28.043 and we train them to turn[br]their heads when a sound changes -- 0:02:28.067,0:02:29.525 like from "ah" to "ee." 0:02:29.549,0:02:32.982 If they do so at the appropriate time,[br]the black box lights up 0:02:33.006,0:02:34.990 and a panda bear pounds a drum. 0:02:35.014,0:02:37.432 A six-monther adores the task. 0:02:38.060,0:02:39.221 What have we learned? 0:02:39.245,0:02:41.405 Well, babies all over the world 0:02:41.429,0:02:44.910 are what I like to describe[br]as "citizens of the world." 0:02:44.946,0:02:47.874 They can discriminate[br]all the sounds of all languages, 0:02:47.898,0:02:51.130 no matter what country we're testing[br]and what language we're using, 0:02:51.154,0:02:54.149 and that's remarkable[br]because you and I can't do that. 0:02:54.173,0:02:56.144 We're culture-bound listeners. 0:02:56.168,0:02:58.563 We can discriminate the sounds[br]of our own language, 0:02:58.587,0:03:00.434 but not those of foreign languages. 0:03:00.458,0:03:03.625 So the question arises:[br]When do those citizens of the world 0:03:03.649,0:03:06.533 turn into the language-bound[br]listeners that we are? 0:03:06.557,0:03:09.694 And the answer:[br]before their first birthdays. 0:03:09.718,0:03:12.850 What you see here is performance[br]on that head-turn task 0:03:12.874,0:03:15.337 for babies tested in Tokyo[br]and the United States, 0:03:15.361,0:03:16.799 here in Seattle, 0:03:16.823,0:03:18.572 as they listened to "ra" and "la" -- 0:03:18.596,0:03:21.402 sounds important to English,[br]but not to Japanese. 0:03:21.426,0:03:24.804 So at six to eight months,[br]the babies are totally equivalent. 0:03:24.828,0:03:27.382 Two months later,[br]something incredible occurs. 0:03:27.406,0:03:30.086 The babies in the United States[br]are getting a lot better, 0:03:30.110,0:03:32.034 babies in Japan are getting a lot worse, 0:03:32.058,0:03:35.508 but both of those groups of babies[br]are preparing for exactly the language 0:03:35.532,0:03:37.024 that they are going to learn. 0:03:37.048,0:03:41.672 So the question is: What's happening[br]during this critical two-month period? 0:03:41.696,0:03:44.039 This is the critical period[br]for sound development, 0:03:44.063,0:03:45.478 but what's going on up there? 0:03:45.502,0:03:47.481 So there are two things going on. 0:03:47.505,0:03:50.381 The first is that the babies[br]are listening intently to us, 0:03:50.405,0:03:54.138 and they're taking statistics[br]as they listen to us talk -- 0:03:54.162,0:03:56.143 they're taking statistics. 0:03:56.167,0:03:58.706 So listen to two mothers[br]speaking motherese -- 0:03:58.730,0:04:01.772 the universal language[br]we use when we talk to kids -- 0:04:01.796,0:04:04.007 first in English and then in Japanese. 0:04:05.231,0:04:08.670 (Video) Ah, I love your big blue eyes -- 0:04:08.694,0:04:11.500 so pretty and nice. 0:04:11.549,0:04:17.476 (Japanese) 0:04:19.406,0:04:21.319 Patricia Kuhl: So, what I'm telling you 0:04:21.351,0:04:25.046 is that during the production[br]of speech, when babies listen, 0:04:25.443,0:04:30.212 what they're doing is taking statistics[br]on the language that they hear. 0:04:30.953,0:04:33.863 And those distributions grow. 0:04:33.887,0:04:38.260 And what we've learned is that babies[br]are sensitive to the statistics, 0:04:38.284,0:04:42.112 and the statistics of Japanese[br]and English are very, very different. 0:04:42.636,0:04:45.293 English has a lot of Rs and Ls. 0:04:45.317,0:04:47.076 The distribution shows. 0:04:47.100,0:04:49.940 And the distribution of Japanese[br]is totally different, 0:04:49.964,0:04:52.965 where we see a group[br]of intermediate sounds, 0:04:52.989,0:04:55.404 which is known as the Japanese "R." 0:04:55.428,0:04:59.536 So babies absorb[br]the statistics of the language 0:04:59.560,0:05:01.238 and it changes their brains; 0:05:01.262,0:05:03.413 it changes them[br]from the citizens of the world 0:05:03.437,0:05:06.383 to the culture-bound[br]listeners that we are. 0:05:06.407,0:05:10.506 But we as adults are no longer[br]absorbing those statistics. 0:05:10.544,0:05:13.101 We are governed[br]by the representations in memory 0:05:13.125,0:05:15.674 that were formed early in development. 0:05:15.698,0:05:17.476 So what we're seeing here 0:05:17.500,0:05:20.733 is changing our models[br]of what the critical period is about. 0:05:20.757,0:05:23.526 We're arguing from[br]a mathematical standpoint 0:05:23.550,0:05:26.690 that the learning of language[br]material may slow down 0:05:26.714,0:05:29.094 when our distributions stabilize. 0:05:29.118,0:05:31.980 It's raising lots of questions[br]about bilingual people. 0:05:32.418,0:05:36.449 Bilinguals must keep two sets[br]of statistics in mind at once 0:05:36.473,0:05:39.356 and flip between them,[br]one after the other, 0:05:39.380,0:05:41.152 depending on who they're speaking to. 0:05:41.176,0:05:42.330 So we asked ourselves, 0:05:42.354,0:05:45.761 can the babies take statistics[br]on a brand new language? 0:05:45.785,0:05:49.063 And we tested this[br]by exposing American babies 0:05:49.087,0:05:50.776 who'd never heard a second language 0:05:50.800,0:05:53.516 to Mandarin for the first time[br]during the critical period. 0:05:53.540,0:05:57.077 We knew that, when monolinguals[br]were tested in Taipei and Seattle 0:05:57.101,0:05:59.763 on the Mandarin sounds,[br]they showed the same pattern. 0:05:59.787,0:06:02.258 Six to eight months,[br]they're totally equivalent. 0:06:02.282,0:06:04.818 Two months later,[br]something incredible happens. 0:06:04.842,0:06:08.394 But the Taiwanese babies are getting[br]better, not the American babies. 0:06:08.418,0:06:13.300 What we did was expose American babies,[br]during this period, to Mandarin. 0:06:13.324,0:06:16.332 It was like having Mandarin relatives[br]come and visit for a month 0:06:16.356,0:06:20.153 and move into your house[br]and talk to the babies for 12 sessions. 0:06:20.177,0:06:22.383 Here's what it looked like[br]in the laboratory. 0:06:22.407,0:06:27.963 (Mandarin) 0:06:44.162,0:06:46.408 PK: So what have we done[br]to their little brains? 0:06:46.432,0:06:48.476 (Laughter) 0:06:48.900,0:06:51.571 We had to run a control group to make sure 0:06:51.595,0:06:54.807 that coming into the laboratory[br]didn't improve your Mandarin skills. 0:06:54.831,0:06:57.484 So a group of babies came in[br]and listened to English. 0:06:57.508,0:06:58.910 And we can see from the graph 0:06:58.934,0:07:01.517 that exposure to English[br]didn't improve their Mandarin. 0:07:01.541,0:07:05.136 But look at what happened to the babies[br]exposed to Mandarin for 12 sessions. 0:07:05.160,0:07:07.560 They were as good as the babies in Taiwan 0:07:07.584,0:07:10.560 who'd been listening[br]for 10 and a half months. 0:07:10.584,0:07:14.408 What it demonstrated is that babies[br]take statistics on a new language. 0:07:14.432,0:07:17.663 Whatever you put in front of them,[br]they'll take statistics on. 0:07:17.700,0:07:19.290 But we wondered what role 0:07:19.314,0:07:22.973 the human being played[br]in this learning exercise. 0:07:22.998,0:07:27.284 So we ran another group of babies[br]in which the kids got the same dosage, 0:07:27.308,0:07:29.776 the same 12 sessions,[br]but over a television set. 0:07:29.800,0:07:33.461 And another group of babies[br]who had just audio exposure 0:07:33.485,0:07:35.573 and looked at a teddy bear on the screen. 0:07:35.597,0:07:37.776 What did we do to their brains? 0:07:37.800,0:07:41.175 What you see here is the audio result -- 0:07:41.523,0:07:43.261 no learning whatsoever -- 0:07:43.285,0:07:45.043 and the video result -- 0:07:45.836,0:07:47.681 no learning whatsoever. 0:07:47.705,0:07:51.846 It takes a human being[br]for babies to take their statistics. 0:07:52.222,0:07:54.388 The social brain is controlling 0:07:54.412,0:07:56.517 when the babies[br]are taking their statistics. 0:07:56.541,0:08:00.034 We want to get inside the brain[br]and see this thing happening 0:08:00.058,0:08:03.996 as babies are in front of televisions,[br]as opposed to in front of human beings. 0:08:04.020,0:08:08.717 Thankfully, we have a new machine,[br]magnetoencephalography, 0:08:08.741,0:08:10.034 that allows us to do this. 0:08:10.058,0:08:12.643 It looks like a hair dryer from Mars. 0:08:12.667,0:08:17.150 But it's completely safe,[br]completely noninvasive and silent. 0:08:17.204,0:08:18.838 And babies - we're looking at 0:08:18.874,0:08:20.632 millimeter accuracy 0:08:20.657,0:08:23.656 with regard to spatial[br]and millisecond accuracy 0:08:23.681,0:08:26.303 using 306 SQUIDs -- 0:08:26.327,0:08:29.427 these are superconducting[br]quantum interference devices -- 0:08:29.451,0:08:33.082 to pick up the magnetic fields[br]that change as we do our thinking. 0:08:33.349,0:08:38.957 We're the first in the world[br]to record babies in an MEG machine 0:08:38.982,0:08:41.373 while they are learning. 0:08:41.397,0:08:43.076 So this is little Emma. 0:08:43.100,0:08:45.008 She's a six-monther. 0:08:45.032,0:08:48.791 And she's listening to various languages[br]in the earphones. 0:08:48.816,0:08:50.799 You can see, she can move around. 0:08:50.822,0:08:54.592 We're tracking her head[br]with little pellets in a cap, 0:08:54.616,0:08:57.591 so she's free to move[br]completely unconstrained. 0:08:57.615,0:08:59.828 It's a technical tour de force. 0:08:59.852,0:09:01.436 What are we seeing? 0:09:01.460,0:09:03.354 We're seeing the baby brain. 0:09:03.378,0:09:07.652 As the baby hears a word in her language,[br]the auditory areas light up, 0:09:07.888,0:09:12.676 and then subsequently areas surrounding it[br]that we think are related to coherence, 0:09:12.700,0:09:16.676 getting the brain coordinated[br]with its different areas, and causality, 0:09:16.700,0:09:19.676 one brain area[br]causing another to activate. 0:09:20.301,0:09:24.758 We are embarking on a grand[br]and golden age. 0:09:24.799,0:09:27.190 We're going to be able[br]to see a child's brain 0:09:27.214,0:09:31.455 as they experience an emotion,[br]as they learn to speak and read, 0:09:31.479,0:09:34.681 as they solve a math problem,[br]as they have an idea. 0:09:35.015,0:09:38.364 And we're going to be able to invent[br]brain-based interventions 0:09:38.388,0:09:40.658 for children who have difficulty learning. 0:09:41.071,0:09:44.137 Just as the poets and writers described, 0:09:44.161,0:09:48.315 we're going to be able to see, I think,[br]that wondrous openness, 0:09:48.339,0:09:51.763 utter and complete openness,[br]of the mind of a child. 0:09:52.524,0:09:55.200 In investigating the child's brain, 0:09:55.224,0:09:59.220 we're going to uncover deep truths[br]about what it means to be human, 0:09:59.244,0:10:00.399 and in the process, 0:10:00.423,0:10:03.494 we may be able to help keep[br]our own minds open to learning 0:10:03.518,0:10:05.209 for our entire lives. 0:10:05.233,0:10:06.476 Thank you. 0:10:06.500,0:10:09.500 (Applause)