1 00:00:16,524 --> 00:00:19,207 I want you to take a look at this baby. 2 00:00:19,679 --> 00:00:24,475 What you're drawn to are her eyes and the skin you love to touch. 3 00:00:24,886 --> 00:00:28,026 But today I'm going to talk to you about something you can't see. 4 00:00:28,050 --> 00:00:30,802 What's going on up in that little brain of hers. 5 00:00:31,635 --> 00:00:35,556 The modern tools of neuroscience are demonstrating to us 6 00:00:35,580 --> 00:00:39,475 that what's going on up there is nothing short of rocket science. 7 00:00:40,236 --> 00:00:43,673 And what we're learning is going to shed some light 8 00:00:43,697 --> 00:00:49,595 on what the romantic writers and poets described as the "celestial openness" 9 00:00:49,619 --> 00:00:51,476 of the child's mind. 10 00:00:52,513 --> 00:00:55,971 What we see here is a mother in India, 11 00:00:55,995 --> 00:00:59,899 and she's speaking Koro, which is a newly discovered language. 12 00:01:00,297 --> 00:01:02,104 And she's talking to her baby. 13 00:01:02,589 --> 00:01:03,745 What this mother -- 14 00:01:03,769 --> 00:01:06,988 and the 800 people who speak Koro in the world -- 15 00:01:07,012 --> 00:01:10,222 understands is that, to preserve this language, 16 00:01:10,246 --> 00:01:12,832 they need to speak it to the babies. 17 00:01:12,856 --> 00:01:15,731 And therein lies a critical puzzle. 18 00:01:15,755 --> 00:01:18,005 Why is it that you can't preserve a language 19 00:01:18,029 --> 00:01:21,264 by speaking to you and I, to the adults? 20 00:01:21,288 --> 00:01:23,476 Well, it's got to do with your brain. 21 00:01:24,038 --> 00:01:28,476 What we see here is that language has a critical period for learning. 22 00:01:28,900 --> 00:01:32,700 The way to read this slide is to look at your age on the horizontal axis. 23 00:01:32,724 --> 00:01:35,407 (Laughter) 24 00:01:35,431 --> 00:01:39,070 And you'll see on the vertical your skill at acquiring a second language. 25 00:01:39,689 --> 00:01:43,548 The babies and children are geniuses until they turn seven, 26 00:01:43,572 --> 00:01:45,876 and then there's a systematic decline. 27 00:01:45,900 --> 00:01:48,397 After puberty, we fall off the map. 28 00:01:48,834 --> 00:01:51,366 No scientists dispute this curve, 29 00:01:51,390 --> 00:01:53,345 but laboratories all over the world 30 00:01:53,369 --> 00:01:55,876 are trying to figure out why it works this way. 31 00:01:56,418 --> 00:02:00,452 Work in my lab is focused on the first critical period in development, 32 00:02:00,476 --> 00:02:02,321 and that is the period in which babies 33 00:02:02,345 --> 00:02:05,710 try to master which sounds are used in their language. 34 00:02:05,734 --> 00:02:08,223 We think, by studying how the sounds are learned, 35 00:02:08,247 --> 00:02:10,513 we'll have a model for the rest of language, 36 00:02:10,537 --> 00:02:13,475 and perhaps for critical periods that may exist in childhood 37 00:02:13,499 --> 00:02:16,362 for social, emotional and cognitive development. 38 00:02:16,935 --> 00:02:18,876 So we've been studying the babies 39 00:02:18,900 --> 00:02:21,403 using a technique that we're using all over the world 40 00:02:21,427 --> 00:02:23,283 and the sounds of all languages. 41 00:02:23,307 --> 00:02:25,098 The baby sits on a parent's lap, 42 00:02:25,122 --> 00:02:28,043 and we train them to turn their heads when a sound changes -- 43 00:02:28,067 --> 00:02:29,525 like from "ah" to "ee." 44 00:02:29,549 --> 00:02:32,982 If they do so at the appropriate time, the black box lights up 45 00:02:33,006 --> 00:02:34,990 and a panda bear pounds a drum. 46 00:02:35,014 --> 00:02:37,432 A six-monther adores the task. 47 00:02:38,060 --> 00:02:39,221 What have we learned? 48 00:02:39,245 --> 00:02:41,405 Well, babies all over the world 49 00:02:41,429 --> 00:02:44,910 are what I like to describe as "citizens of the world." 50 00:02:44,946 --> 00:02:47,874 They can discriminate all the sounds of all languages, 51 00:02:47,898 --> 00:02:51,130 no matter what country we're testing and what language we're using, 52 00:02:51,154 --> 00:02:54,149 and that's remarkable because you and I can't do that. 53 00:02:54,173 --> 00:02:56,144 We're culture-bound listeners. 54 00:02:56,168 --> 00:02:58,563 We can discriminate the sounds of our own language, 55 00:02:58,587 --> 00:03:00,434 but not those of foreign languages. 56 00:03:00,458 --> 00:03:03,625 So the question arises: When do those citizens of the world 57 00:03:03,649 --> 00:03:06,533 turn into the language-bound listeners that we are? 58 00:03:06,557 --> 00:03:09,694 And the answer: before their first birthdays. 59 00:03:09,718 --> 00:03:12,850 What you see here is performance on that head-turn task 60 00:03:12,874 --> 00:03:15,337 for babies tested in Tokyo and the United States, 61 00:03:15,361 --> 00:03:16,799 here in Seattle, 62 00:03:16,823 --> 00:03:18,572 as they listened to "ra" and "la" -- 63 00:03:18,596 --> 00:03:21,402 sounds important to English, but not to Japanese. 64 00:03:21,426 --> 00:03:24,804 So at six to eight months, the babies are totally equivalent. 65 00:03:24,828 --> 00:03:27,382 Two months later, something incredible occurs. 66 00:03:27,406 --> 00:03:30,086 The babies in the United States are getting a lot better, 67 00:03:30,110 --> 00:03:32,034 babies in Japan are getting a lot worse, 68 00:03:32,058 --> 00:03:35,508 but both of those groups of babies are preparing for exactly the language 69 00:03:35,532 --> 00:03:37,024 that they are going to learn. 70 00:03:37,048 --> 00:03:41,672 So the question is: What's happening during this critical two-month period? 71 00:03:41,696 --> 00:03:44,039 This is the critical period for sound development, 72 00:03:44,063 --> 00:03:45,478 but what's going on up there? 73 00:03:45,502 --> 00:03:47,481 So there are two things going on. 74 00:03:47,505 --> 00:03:50,381 The first is that the babies are listening intently to us, 75 00:03:50,405 --> 00:03:54,138 and they're taking statistics as they listen to us talk -- 76 00:03:54,162 --> 00:03:56,143 they're taking statistics. 77 00:03:56,167 --> 00:03:58,706 So listen to two mothers speaking motherese -- 78 00:03:58,730 --> 00:04:01,772 the universal language we use when we talk to kids -- 79 00:04:01,796 --> 00:04:04,007 first in English and then in Japanese. 80 00:04:05,231 --> 00:04:08,670 (Video) Ah, I love your big blue eyes -- 81 00:04:08,694 --> 00:04:11,500 so pretty and nice. 82 00:04:11,549 --> 00:04:17,476 (Japanese) 83 00:04:19,406 --> 00:04:21,319 Patricia Kuhl: So, what I'm telling you 84 00:04:21,351 --> 00:04:25,046 is that during the production of speech, when babies listen, 85 00:04:25,443 --> 00:04:30,212 what they're doing is taking statistics on the language that they hear. 86 00:04:30,953 --> 00:04:33,863 And those distributions grow. 87 00:04:33,887 --> 00:04:38,260 And what we've learned is that babies are sensitive to the statistics, 88 00:04:38,284 --> 00:04:42,112 and the statistics of Japanese and English are very, very different. 89 00:04:42,636 --> 00:04:45,293 English has a lot of Rs and Ls. 90 00:04:45,317 --> 00:04:47,076 The distribution shows. 91 00:04:47,100 --> 00:04:49,940 And the distribution of Japanese is totally different, 92 00:04:49,964 --> 00:04:52,965 where we see a group of intermediate sounds, 93 00:04:52,989 --> 00:04:55,404 which is known as the Japanese "R." 94 00:04:55,428 --> 00:04:59,536 So babies absorb the statistics of the language 95 00:04:59,560 --> 00:05:01,238 and it changes their brains; 96 00:05:01,262 --> 00:05:03,413 it changes them from the citizens of the world 97 00:05:03,437 --> 00:05:06,383 to the culture-bound listeners that we are. 98 00:05:06,407 --> 00:05:10,506 But we as adults are no longer absorbing those statistics. 99 00:05:10,544 --> 00:05:13,101 We are governed by the representations in memory 100 00:05:13,125 --> 00:05:15,674 that were formed early in development. 101 00:05:15,698 --> 00:05:17,476 So what we're seeing here 102 00:05:17,500 --> 00:05:20,733 is changing our models of what the critical period is about. 103 00:05:20,757 --> 00:05:23,526 We're arguing from a mathematical standpoint 104 00:05:23,550 --> 00:05:26,690 that the learning of language material may slow down 105 00:05:26,714 --> 00:05:29,094 when our distributions stabilize. 106 00:05:29,118 --> 00:05:31,980 It's raising lots of questions about bilingual people. 107 00:05:32,418 --> 00:05:36,449 Bilinguals must keep two sets of statistics in mind at once 108 00:05:36,473 --> 00:05:39,356 and flip between them, one after the other, 109 00:05:39,380 --> 00:05:41,152 depending on who they're speaking to. 110 00:05:41,176 --> 00:05:42,330 So we asked ourselves, 111 00:05:42,354 --> 00:05:45,761 can the babies take statistics on a brand new language? 112 00:05:45,785 --> 00:05:49,063 And we tested this by exposing American babies 113 00:05:49,087 --> 00:05:50,776 who'd never heard a second language 114 00:05:50,800 --> 00:05:53,516 to Mandarin for the first time during the critical period. 115 00:05:53,540 --> 00:05:57,077 We knew that, when monolinguals were tested in Taipei and Seattle 116 00:05:57,101 --> 00:05:59,763 on the Mandarin sounds, they showed the same pattern. 117 00:05:59,787 --> 00:06:02,258 Six to eight months, they're totally equivalent. 118 00:06:02,282 --> 00:06:04,818 Two months later, something incredible happens. 119 00:06:04,842 --> 00:06:08,394 But the Taiwanese babies are getting better, not the American babies. 120 00:06:08,418 --> 00:06:13,300 What we did was expose American babies, during this period, to Mandarin. 121 00:06:13,324 --> 00:06:16,332 It was like having Mandarin relatives come and visit for a month 122 00:06:16,356 --> 00:06:20,153 and move into your house and talk to the babies for 12 sessions. 123 00:06:20,177 --> 00:06:22,383 Here's what it looked like in the laboratory. 124 00:06:22,407 --> 00:06:27,963 (Mandarin) 125 00:06:44,162 --> 00:06:46,408 PK: So what have we done to their little brains? 126 00:06:46,432 --> 00:06:48,476 (Laughter) 127 00:06:48,900 --> 00:06:51,571 We had to run a control group to make sure 128 00:06:51,595 --> 00:06:54,807 that coming into the laboratory didn't improve your Mandarin skills. 129 00:06:54,831 --> 00:06:57,484 So a group of babies came in and listened to English. 130 00:06:57,508 --> 00:06:58,910 And we can see from the graph 131 00:06:58,934 --> 00:07:01,517 that exposure to English didn't improve their Mandarin. 132 00:07:01,541 --> 00:07:05,136 But look at what happened to the babies exposed to Mandarin for 12 sessions. 133 00:07:05,160 --> 00:07:07,560 They were as good as the babies in Taiwan 134 00:07:07,584 --> 00:07:10,560 who'd been listening for 10 and a half months. 135 00:07:10,584 --> 00:07:14,408 What it demonstrated is that babies take statistics on a new language. 136 00:07:14,432 --> 00:07:17,663 Whatever you put in front of them, they'll take statistics on. 137 00:07:17,700 --> 00:07:19,290 But we wondered what role 138 00:07:19,314 --> 00:07:22,973 the human being played in this learning exercise. 139 00:07:22,998 --> 00:07:27,284 So we ran another group of babies in which the kids got the same dosage, 140 00:07:27,308 --> 00:07:29,776 the same 12 sessions, but over a television set. 141 00:07:29,800 --> 00:07:33,461 And another group of babies who had just audio exposure 142 00:07:33,485 --> 00:07:35,573 and looked at a teddy bear on the screen. 143 00:07:35,597 --> 00:07:37,776 What did we do to their brains? 144 00:07:37,800 --> 00:07:41,175 What you see here is the audio result -- 145 00:07:41,523 --> 00:07:43,261 no learning whatsoever -- 146 00:07:43,285 --> 00:07:45,043 and the video result -- 147 00:07:45,836 --> 00:07:47,681 no learning whatsoever. 148 00:07:47,705 --> 00:07:51,846 It takes a human being for babies to take their statistics. 149 00:07:52,222 --> 00:07:54,388 The social brain is controlling 150 00:07:54,412 --> 00:07:56,517 when the babies are taking their statistics. 151 00:07:56,541 --> 00:08:00,034 We want to get inside the brain and see this thing happening 152 00:08:00,058 --> 00:08:03,996 as babies are in front of televisions, as opposed to in front of human beings. 153 00:08:04,020 --> 00:08:08,717 Thankfully, we have a new machine, magnetoencephalography, 154 00:08:08,741 --> 00:08:10,034 that allows us to do this. 155 00:08:10,058 --> 00:08:12,643 It looks like a hair dryer from Mars. 156 00:08:12,667 --> 00:08:17,150 But it's completely safe, completely noninvasive and silent. 157 00:08:17,204 --> 00:08:18,838 And babies - we're looking at 158 00:08:18,874 --> 00:08:20,632 millimeter accuracy 159 00:08:20,657 --> 00:08:23,656 with regard to spatial and millisecond accuracy 160 00:08:23,681 --> 00:08:26,303 using 306 SQUIDs -- 161 00:08:26,327 --> 00:08:29,427 these are superconducting quantum interference devices -- 162 00:08:29,451 --> 00:08:33,082 to pick up the magnetic fields that change as we do our thinking. 163 00:08:33,349 --> 00:08:38,957 We're the first in the world to record babies in an MEG machine 164 00:08:38,982 --> 00:08:41,373 while they are learning. 165 00:08:41,397 --> 00:08:43,076 So this is little Emma. 166 00:08:43,100 --> 00:08:45,008 She's a six-monther. 167 00:08:45,032 --> 00:08:48,791 And she's listening to various languages in the earphones. 168 00:08:48,816 --> 00:08:50,799 You can see, she can move around. 169 00:08:50,822 --> 00:08:54,592 We're tracking her head with little pellets in a cap, 170 00:08:54,616 --> 00:08:57,591 so she's free to move completely unconstrained. 171 00:08:57,615 --> 00:08:59,828 It's a technical tour de force. 172 00:08:59,852 --> 00:09:01,436 What are we seeing? 173 00:09:01,460 --> 00:09:03,354 We're seeing the baby brain. 174 00:09:03,378 --> 00:09:07,652 As the baby hears a word in her language, the auditory areas light up, 175 00:09:07,888 --> 00:09:12,676 and then subsequently areas surrounding it that we think are related to coherence, 176 00:09:12,700 --> 00:09:16,676 getting the brain coordinated with its different areas, and causality, 177 00:09:16,700 --> 00:09:19,676 one brain area causing another to activate. 178 00:09:20,301 --> 00:09:24,758 We are embarking on a grand and golden age. 179 00:09:24,799 --> 00:09:27,190 We're going to be able to see a child's brain 180 00:09:27,214 --> 00:09:31,455 as they experience an emotion, as they learn to speak and read, 181 00:09:31,479 --> 00:09:34,681 as they solve a math problem, as they have an idea. 182 00:09:35,015 --> 00:09:38,364 And we're going to be able to invent brain-based interventions 183 00:09:38,388 --> 00:09:40,658 for children who have difficulty learning. 184 00:09:41,071 --> 00:09:44,137 Just as the poets and writers described, 185 00:09:44,161 --> 00:09:48,315 we're going to be able to see, I think, that wondrous openness, 186 00:09:48,339 --> 00:09:51,763 utter and complete openness, of the mind of a child. 187 00:09:52,524 --> 00:09:55,200 In investigating the child's brain, 188 00:09:55,224 --> 00:09:59,220 we're going to uncover deep truths about what it means to be human, 189 00:09:59,244 --> 00:10:00,399 and in the process, 190 00:10:00,423 --> 00:10:03,494 we may be able to help keep our own minds open to learning 191 00:10:03,518 --> 00:10:05,209 for our entire lives. 192 00:10:05,233 --> 00:10:06,476 Thank you. 193 00:10:06,500 --> 00:10:09,500 (Applause)