The Science of Learning & Speaking Languages | Dr. Eddie Chang

安德鲁·休伯曼： Welcome to the Huberman Lab 播客, where 我们 discuss science 和 science-based tools 对于 everyday life. I'm Andrew Huberman, 和 I'm a professor of 神经生物学 和 ophthalmology at Stanford School of Medicine. Today, my guest is Dr. Eddie Chang. Dr. Eddie Chang is the chair of the neurosurgery department at the University of California at San Francisco. Dr. Chang's clinical group focuses on the treatment of movement disorders, including epilepsy. He is also a world expert in the treatment of speech disorders 和 relieving paralysis 那 prevents speech 和 other forms of movement 和 communication. Indeed, his laboratory is credited 与 discovering ways to allow 人们 who have fully locked-in syndrome, 那 is, who cannot speak 或 move, to communicate 通过 computers 和 AI devices in order to be able to speak to others in their world 和 understand what others are saying to them. It is a truly remarkable achievement 那 我们 discuss today. In addition to his discoveries 关于 critical periods, which are periods of time 期间 一's life when 一 可以 learn things, in particular languages, 与 great ease as opposed to later in life, 和 我们 talk 关于 the basis of things like bilingualism 和 trilingualism. 我们 talk 关于 how the 大脑 controls movement of the 非常 肌肉 那 allow 对于 speech 和 language, 和 how 那些 可以 be modified over time. 我们 also talk 关于 stutter, 和 我们 talk 关于 a number of aspects of speech 和 language 那 give insight 进入 not just how 我们 create 这 incredible thing called speech 或 how 我们 understand speech 和 language, 但 how the 大脑 works 更多 generally. Dr. Chang is also 一 of the world leaders in bioengineering. 那 is, the creation of devices 那 allow the 大脑 to function at super physiological 水平 和 那 可以 allow 人们 与 various syndromes 和 disorders to overcome their deficits. So if 你 are somebody who is interested in how the 大脑 works normally, how it breaks down, 和 how it 可以 be repaired, 和 if 你 are interested in speech 和 language, reading, 和 comprehension of information of any kind, today's episode ought to include some information of deep interest to 你. Dr. Chang is indeed the top of his field in terms of understanding 这些 issues of how the 大脑 encodes speech 和 language 和 creates speech 和 language, 和 as I mentioned, movement disorders 和 epilepsy. 我们 even talk 关于 things such as the ketogenic diet, the future of companies like Neuralink, which are interested in bioengineering 和 augmenting the human 大脑, 和 much 更多. 一 thing 那 I 会 like to note is 那 in addition to being a world-class neuroscience researcher 和 world-class clinician neurosurgeon 和 chair of neurosurgery, Dr. Eddie Chang has also been a close personal friend of mine since 我们 were nine years old. 我们 attended elementary school together, 和 我们 actually had a science club when 我们 were nine years old, focused on a 非常 particular topic. 你'll have to listen in to today's episode to discover what 那 topic was 和 what membership to 那 club required. 那 aside, Dr. Chang is an absolute phenom 与 respect to his scientific prowess, 那 is, both his 研究 和 his clinical abilities, 和 he's 一 of 这些 rare 个体 那 whenever he opens his mouth, 我们 learn. 之前 我们 begin, I'd like to emphasize 那 这 podcast is separate 从 my teaching 和 研究 roles at Stanford. It is, 然而, part of my desire 和 effort to bring zero cost to consumer information 关于 science 和 science-related tools to the general public. In keeping 与 那 theme, I'd like to thank the sponsors of today's podcast. 和 now 对于 my discussion 与 Dr. Eddie Chang. Eddie, welcome.

Dr. Eddie Chang: Hi. Hi, Andrew.

安德鲁·休伯曼： Great to be here 与 你. 这 has been a long time coming. Just to come clean, 我们've known each other since 我们 were nine years old.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 但 then there was a long gap in which 我们 didn't talk to 一 another. I heard things 关于 你, 和 presumably 你 heard a thing 或 二 关于 me, 对于 better 或 对于 worse. 和 then 我们 reconnected years later when I was a PhD student 和 你 were a medical student. 我们 literally ran 进入 each other in the halls of University of California, San Francisco, where 你're now the Chair of Neurosurgery. So it all comes full circle. When 你 were at UCSF, 你 were working 与 Mike Merzenich, 和 I know 那 name 可能 not be familiar to a lot of 人们, 但 he's sort of synonymous 与 neuroplasticity, the ability of the 大脑 和 神经系统 to change in response to experience. So 对于 我们的 listeners, I 会 just love 对于 你 to give a brief overview of what 你 were doing at 那 time, 因为 I find 那 work so fascinating, 和 it 确实 points to some of the things 那 可以 promote 和 maybe hinder 我们的 大脑's ability to change.

Dr. Eddie Chang: Oh, wow. 那's fantastic. So 我们 did bump 进入 each other serendipitously back then, 和 at the time, I was a medical student at UCSF studying 与 Mike Merzenich. In particular, I was studying how the 大脑 organizes when 你 have patterns of sound. 和 in particular, 我们 were studying the 大脑 of rodents 和 trying to understand how 不同的 sound patterns organize the frequency representation 从 low to middle to high-frequency maps in the brains of baby rodents. 和 一 of the things 那 I was 非常 interested in was trying to understand how the patterns of the natural environment, let's say the vocalizations of the environment 那 the rat pups were raised in 或 just the natural sounds 那 they hear, how 那 shapes the structure of the 大脑. 和 一 of the things 我们 did was to try 和 experiment where 我们 raised some of 这些 rat pups in white noise, continuous white noise, 那 was 本质上 masking all of 那些 environmental sounds.

安德鲁·休伯曼： 和 what was the consequence of animals being raised in white noise environment?

Dr. Eddie Chang: Well, 一 of the things 那 我们 didn't expect 但 我们 found, which is quite striking, is 那 there's 这 early period in 大脑 development where 我们're 非常 susceptible to the patterns 那 我们 hear 或 see. In neuroscience, 我们 call 这 a critical period 或 a sensitive period. 和 我们 have 这 对于 我们的 eyes, 但 我们 also have it 对于 我们的 ears. 和 一 of the most striking examples of 这 is 那 any human 可以 本质上 grow up in a culture where they hear 不同的 speech sounds 从 一 language to another, 和 it's like 之后 a couple of years, 你 lose sensitivity to sounds 那 are not part of 你的 native language, 和 你 have high sensitivity 对于 the languages of 你的 native culture. 和 那's pretty extraordinary 那 human 大脑 has 那 flexibility, yet at the same time has 那 specialization 对于 language. 和 so 我们 were trying to think 关于 how do 我们 model 这, 对于 example, in rodents who obviously don't speak, 但 我们're just understanding how sounds 和 environmental sounds modulate 和 organize the auditory cortex. 和 一 of the things 那 我们 found 那 was quite striking was 那 if 你 basically mask environmental sounds 从 这些 rat pups, the critical period, 这 sensitive period where it's open to plasticity, it's open to change, it's open to reorganization, 那 window 可以 stay open much, much longer. 和 in 一 way it sounds like 那's a good thing, 但 on the other hand, it's also a retardation. It slowed the maturation of the auditory cortex. It was ready to close when 这些 rat pups were 确实 young, 但 by raising them in white noise, 我们 found out 那 你 could keep it open 对于 months beyond the time period 那 it normally closes. 和 so I think 一 of the things it taught me was 那 it's not just 关于 the genetic programming 那 specifies some of 这 sensitive period, 但 it's also a little bit 关于 the nature of the sounds 那 我们 hear 那 help keep 那 window 对于 the critical period open 和 closed.

安德鲁·休伯曼： It's fascinating, 和 I know it's difficult to make a direct leap 从 animal 研究 to human 研究, 但 if 我们 could speculate a little bit, I 可以 imagine 那 some 人们 grow up in homes where there's a lot of shouting 和 a lot of inflection. Maybe 人们 are 非常 verbose.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Maybe others grow up in a home where it's quieter 和 更多 peaceful. Some 人们 are going to grow up in cities. I just came back 从 New York City, it's like all 夜间 long there's honking 和 sirens, 和 it's just nonstop. 和 then I return here where it's quite quiet at 夜间. 可以 我们 imagine 那 the human 大脑 is going to be shaped differently depending on whether 或 not 一 grows up in 一 environment 或 another? 和 会 那 impact their tendency to speak in a certain way as well as hear in a certain way? What do 我们 know 关于 那?

Dr. Eddie Chang: Well, I think 那 从 my perspective, it's 确实 clear 那 那些 sounds 那 我们 are exposed to 从 the 非常 earliest time, even in utero, in the womb, where the sound is hearing the mother 或 father 或 friends 大约 while in the womb actually 会 influence how 这些 things organize. 和 so there's no question 那 the sounds 那 我们 hear are going to have some influence, 和 那些 sounds are going to structure the way 那 那些 neural networks actually lay down 和 会 forever influence how 你 hear sounds. 和 speech 和 language is probably 一 of the most profound examples of 那.

安德鲁·休伯曼： I get a lot of questions 关于 the use of white noise 期间 sleep. In particular, 人们 want to know whether 或 not using a white noise machine 或 a machine 或 a program 那 makes the sound of waves, 对于 instance, if it assists their infant in sleeping, is it going to be bad 对于 them 因为 it's flooding the auditory 系统 与 a bunch of 本质上 white noise 或 disorganized noise? Do 我们 have an answer to 那 question?

Dr. Eddie Chang: Not yet. I think 那 what 你're asking is a 确实 重要 question 因为 parents are using white noise generators almost universally now, 和 对于 good reasons. It is hard to have kids up at 夜间. I've got 三 kids of my own 和 was 非常 tempted to think 关于 how to use some of 这些 tools to just soothe them 和 get them to bed, 尤其是 when I was so tired 和 exhausted. 但 I think 那 there is a cost to think a little bit 关于. 我们're not exposed to continuous white noise naturally. There is a value to having 确实 salient, structured sounds 那 are part of 我们的 natural environment to actually have the 大脑 develop normally. So, whether 或 not 那 has an impact while 你're sleeping, it's not clear. I don't think 那 那些 研究 have been done. What was 确实 clear was 那 if 你 raise 这些 baby rats in continuous white noise, not super loud, 但 just enough to mask the environmental sounds, 那 那 was enough to keep the auditory cortex, the part of the 大脑 那 hears, in 这 确实 delayed state, which could 本质上 slow down the development 和 maturation of the 大脑.

安德鲁·休伯曼： 和 一 could probably assume 那 slowing the maturation of areas of the 大脑 那 are responsible 对于 hearing 可能, I want to underscore, 可能 impact 一's ability to speak. Right? 因为 isn't it the case 那 if 人们 可以't hear, they actually have a harder time enunciating in a particular way? Is 那 right?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： If I were to not be able to hear my own voice, 会 my speech patterns change?

Dr. Eddie Chang: Well, I think part of it is 那 over time 我们 develop sensitivity to the 非常 具体的 speech sounds in a given language, 和 the sensitivity 改善 as 我们 hear 更多 和 更多 和 更多 of it. 和 then on the other hand, 我们 lose sensitivity to other speech sounds at the same time. 但 as part of 那 process, 我们 also have a selectivity, a gain, a specialization even 对于 那些 sounds, even relative to noise, noisy backgrounds 和 things like 那. I tend to think 关于 it like what is the signal-to-noise ratio? 和 so the 大脑 has its own ways of trying to 增加 那 signal-to-noise ratio in order to make it 更多 clear. Part of 那 is how 我们 hear 和 how it lays down a foundation 对于 那 signal-to-noise ratio. 和 so 你 可以 imagine a child 那's raised continuously in white noise 会 be 确实 deprived of 那些 kind of sounds 那 are 确实 necessary 对于 it to develop properly. So I think 与 regard to 那些 tools 对于 babies, I think 我们 应该 研究. 我们 应该 try to understand 这 definitively. I think what 我们 saw in rodents 会 tell us 那 there is potential, things 那 我们 应该 be concerned 关于, 但 again, it's not 确实 clear if 你're just using at 夜间 whether it has 那些 effects.

安德鲁·休伯曼： I guess the critical question 那 a number of 人们 are going to be asking is, did 你 decide to use a white noise machine 或 not to help keep any of 你的 三 children asleep?

Dr. Eddie Chang: Yeah. Well, I think the short answer is no. I obviously did a lot of work thinking 和 work on 这 和 thought 关于 it carefully. 但 there are other kinds of noise, 或 I wouldn't even call it noise, other sounds 那 你 可以 use 那 可以 be equally soothing to a baby. It's just 那 white noise has no structure 和 what it's doing is 本质上 masking out all of the natural sounds. 和 I think the goal 应该 确实 be 关于 how do 我们 replace 那 与 other 更多 natural sounds 那 structure the 大脑 in the way 那 我们 want to be 更多 healthy.

安德鲁·休伯曼： Well, I know 那 之后 你 finished 你的 medical 训练, 你 went on to, of course, specialize in neurosurgery, 和 last I checked, 你 spend most of 你的 天 either running 你的 laboratory 或 in the clinic 或 running the department. 和 你的 clinical work 和 你的 laboratory work involves 经常 removing pieces of the skull of humans 和 going in 和 either removing things 或 stimulating neurons, treating various ailments of 不同的 kinds. 但 你的 main 专注 这些 天, of course, is the 神经生物学 of speech 和 language. 和 so 对于 那些 那 aren't familiar, could 你 please distinguish 对于 us speech versus language in terms of whether 或 not 不同的 大脑 areas control them? 和 I know 那 there's a lot of interest in how speech 和 language 和 hearing all relate to 一 another.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 和 then 我们'll talk a bit 关于, 对于 instance, emotions 和 how facial expressions could play 进入 这 或 hand gestures, et cetera. 但 对于 the uninformed person, 和 对于 me, to be quite direct, what are the 大脑 areas 那 control speech 和 language? What are they 确实? 和 尤其是 in humans, how are they 不同的? 我们 have such sophisticated language compared to a number of other species. What does all 这 landscape look like in there?

Dr. Eddie Chang: Yeah. Well, 那's a fascinating question, 和 I'm going to just try to connect a couple of the dots here, which is 那 in 那 earlier work 期间 medical school, I was doing a lot of what 我们 call neurophysiology, putting electrodes 进入 the auditory cortex 和 understanding how the 大脑 responds to sounds. 和 那's how 我们 actually mapped out 这些 things 关于 the sensitivity to sensitive periods. 那 experience 与 Mike Merzenich 和 thinking 关于 how plasticity is regulated in the 大脑, in particular 关于 how sound is represented by 大脑 activity, was something 那 was 确实 formative 对于 me. 和 因为 I was a medical student 和 I was going back to my medical 研究, it was 那 in combination 与 seeing some awake 大脑 surgeries 那 我们的 department is 确实 well known 对于. 一 of my mentors, Mitch Berger, 确实 pioneered 这些 methods 对于 taking care of patients 与 大脑 tumor 和 be able to do 这些 surgeries safely by keeping patients awake 和 by mapping out language.

安德鲁·休伯曼： So they're talking 和 listening, 和 你're 本质上 in conversation 与 这些 patients while there's a portion of their skull removed, 和 你 are stimulating 或, in some cases, removing areas of their 大脑. Is 那 right?

Dr. Eddie Chang: 那's exactly right. 和 the only thing off there is it's not 本质上. It is just 那. The only difference between the conversation 那 I 可能 have 与 my patient who's undergoing awake 大脑 surgery is 那 I 可以't see their face 和 they 可以't see my face. 我们 actually have a sterile drape 那 actually separates the operating field, 和 they're looking 和 interacting 与 我们的 neuropsychologist. 但 I 可以 talk to them 和 they 可以 hear my voice 和 vice versa. 和 it's a 确实, 确实 重要 way of how 我们 可以 protect some of 那些 areas 那 are 确实 critical 对于 language. At the same time, accomplish the mission of getting the seizures under control 或 getting a 大脑 tumor removed.

安德鲁·休伯曼： 和 is 那 因为 occasionally 你'll encounter a 大脑 area, maybe 你're stimulating 或 considering removing 那 大脑 area, 和 suddenly a patient 会 start stuttering 或 会 have a hard time formulating a sentence? Is 那 本质上 what 你're looking 对于? 你're looking 对于 regions in which it is okay 或 not okay to probe.

Dr. Eddie Chang: Exactly. So the 首先 thing 那 我们 do is 那 我们 use a small electrical stimulator to probe 不同的 parts of the areas 那 我们 think 可能 be related 和 重要 对于 language 或 talking 或 even movements of 你的 arm 和 leg. 那's what 我们 call 大脑 mapping. 和 我们 use a small electrical current 那's delivered 通过 a probe 那 我们 可以 just put at each spot. 和 the areas 那 我们're 确实 interested in are, of course, the areas 那 are right 大约 the part 那 is pathological, the part 那's injured 或 the part 那 has a 大脑 tumor 那 我们 want to remove. So 我们 可以 apply 那 probe 和 transiently, meaning temporarily activate it. So if 你're stimulating the part of the 大脑 那 controls the hand, the hand 会 move. It 会 jerk. Sometimes a fist 会 be made, something like 那. Other times, while someone is counting 或 just saying the 天 of the 周, 你 可以 stimulate in a 不同的 area 那 stops their speech altogether. 那's what 我们 call speech arrest. 或 if someone is looking at pictures 和 they're describing the pictures 和 你 stimulate in a particular area, they stop speaking, 或 the words start coming out slurred, 或 they 可以't remember the name of the object 那 they're seeing in the picture. 这些 are all things 那 我们're listening 确实 carefully While 我们 apply 那 focal stimulation. 那's what 我们 call 大脑 mapping.

安德鲁·休伯曼： What are some of the 更多 surprising 或 maybe even if 你 want to offer, what are the 更多 outrageous examples of things 那 人们 have suddenly done 或 failed to be able to do as a consequence of 这 大脑 mapping?

Dr. Eddie Chang: Well, I think the thing to me 那 has been the most striking is 那 some of 这些 areas 你 stimulate 和 altogether, 你 可以 shut down someone's talking. So person says, "I wanted to say it, 但 I couldn't get the words out." 和 even though I've seen 这 thousands of times now, it's still exciting every time 那 I see it 因为 it's exciting 因为 你're seeing the 大脑. It's a physical organ. It's part of the 身体. Outside of the veins, on top of it, doesn't look like a machine. 但 when 你 do something like 那 和 你 focally change the way it works, 和 你 see 那 因为 a person 可以't talk anymore, 和 they say, "I know what I want to say, 但 I couldn't get the words out," 你're confronted 与 这 idea 那, 那 organ is the basis of speech 和 language, 和 way beyond 那, obviously. 对于 all the other functions 那 我们 have 对于 thinking 和 feeling 我们的 emotions, everything. So 那 to me is a constant reminder of 这 确实 special thing 那 the 大脑 does, which is compute so many of the things 那 我们 do, 和 in particular in the area 大约 speech 和 language, generating words. Something 那 is 确实 unique to 我们的 species is just extraordinary to see. Again, even though I've seen it thousands of times, it's just having 那 connection 因为 it doesn't look like a machine, 但 it is doing something 那 is quite complicated, precise, 和 remarkable.

安德鲁·休伯曼： Do 你 ever see emotional responses 从 stimulation in particular areas? 和 do 你 ever hear 或 see emotional responses 那 are associated 与 particular types of speech? 因为 对于 instance, curse words-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... are known to-- 人们 与 Tourette's 经常 会 curse.

Dr. Eddie Chang: Sure.

安德鲁·休伯曼： Not 总是, 但 sometimes they'll have tics 或 other things.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 但 what I learned 从 a colleague of ours is 那 curse words have a certain structure to them. There's usually a heavy 或 kind of a sharp consonant up front, right, 那 allows 人们, at least as it was described to me, to have some sort of emotional 释放. It's not a word like murmur-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... which has a kind of a soft entry.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Here, I'm not using the technical language.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 和 你 pick 你的 favorite curse word out there, folks. I'm not going to shout out any now 或 say any now. 但 那 certain words have a structure to them 那 因为 of the motor patterns 那 are involved in saying 那 word-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 你 could imagine has an emotional response unto itself. So when stimulating 或 when blocking 这些 不同的 大脑 areas, do 你 ever see 人们 get angry 或 sad 或 happy 或 更多 relaxed?

Dr. Eddie Chang: Oh, well, definitely I've seen cases where 你 可以 invoke anxiety, 压力. 和 I think 那 there are also areas 那 你 可以 stimulate, 和 你 可以 also evoke the opposite of 那, sort of like a calm state.

安德鲁·休伯曼： I think 那 大脑 area is slightly hyperactive in 你, 或 at least 更多 than me. In all the years I've known 你, 你've 总是 been, at least externally, a 非常 calm person. I 总是 find it amazing 那 你 work on speech 和 language-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 和 你 have a 非常 calming voice, right? 和 I'm being 确实 serious. I think 那 there's a huge variation there, right, in terms of how 人们 speak 和 how they accent words.

Dr. Eddie Chang: Absolutely. Yeah. So there are areas, 对于 example, the orbitofrontal cortex, 那 我们 showed 那 if 你 stimulate there, the orbitofrontal cortex is a part of the 大脑 那's above the eyes, 那's why they call it orbitofrontal, meaning it's above the eye 或 the orbit, 和 in the frontal lobe, 和 it's 这 area right in here. It has 确实 complex functions. It's 确实 重要 对于 learning 和 memory. 但 一 of the things 那 我们 observed is when 你 stimulate in there, 人们 tended to have a reduction in their 压力. 和 it was 非常 much related to their state of being, meaning 那 if someone was already kind of feeling normal 和 你 stimulate there, it didn't do much. 但 if someone was in a 非常 anxious state, it actually relieved 那. 和 then 我们've seen the corollary of 那, which is true, too, which is 那 there are other areas like the amygdala 或 parts of the insula, 那 if 你 stimulate, 你 可以 cause an acute temporary anxiety, a nervous feeling. 或 if 你 stimulate insula, 人们 可以 have an acute feeling of disgust. So, the 大脑 has 不同的 functions 和 这些 不同的 nodes 那 help process the way 我们 feel. Certainly, I think 那 to some degree, neuropsychiatric conditions reflect an imbalance of the electrical activities in 这些 areas. 一 of the things 那 was something I 会 从不 forget was taking care of a young woman 与 uncontrolled seizures. 我们 call 那 epilepsy. It's a medical condition where someone has uncontrolled electrical activity in the 大脑. Sometimes 你 可以 see 那 as convulsions, where 人们 are shaking 和 lose consciousness. There are other kind of seizures 那 人们 可以 have where they don't lose consciousness, 但 they 可以 have experiences 那 just come out of nowhere. 和 it's just as a result of electrical activity coming 从 the 大脑. 和 关于 six years ago, I took care of a young woman who was diagnosed psychiatrically 与 anxiety disorder 对于 several years. It turns out 那 it wasn't 确实 an anxiety disorder, it was actually 那 she had underlying seizures 和 epilepsy activating a part of her 大脑 那 evokes anxious feelings.

安德鲁·休伯曼： How was 那 discovered? 因为 I know a lot of 人们 out there have anxiety.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： In the absence of a 大脑 scan, how 或 why 会 一 suspect 那 maybe they have a tumor 或 some other condition 那 was causing 那些 neurons to become hyperactive?

Dr. Eddie Chang: Yeah, 那's 确实 重要 因为 so many 人们 have anxiety, 和 the vast, vast majority are not having 那 因为 they're having seizures in the 大脑. I think 一 of the ways 那 这 was diagnosed was 那 the nature of when she was having 这些 panic attacks was not triggered by anything. They 会 just happen spontaneously. 和 那's what 可以 happen 与 seizures sometimes. They just come out of nowhere. 我们 don't fully understand what 可以 trigger them, 但 they weren't things 那 were 通常 anxiety-provoking. 这 is something 那 just happened all of a sudden. 和 因为 你 brought it up, 这 is not something 那 你 可以 see on an MRI. 我们 could not see 和 look at the structure of her 大脑 与 an MRI 那 she was having seizures. The only way 那 我们 could actually prove 这 was actually putting electrodes 进入 her 大脑 和 proving 那 这些 attacks 那 she was having were localized to a part called the amygdala. It's a medial part of the temporal lobe, which is here, 和 associating the electrical activity 那 我们 were seeing on 那些 electrodes 与 the symptoms 那 she had. 和 she ultimately needed a kind of surgery where she was awake in order to remove 这 safely.

安德鲁·休伯曼： Speaking of epilepsy, a number of 人们 out there have epilepsy 或 know 人们 who do. Are the drugs 对于 epilepsy satisfactory? I think 关于 things like Depakote 和-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 和 adjusting the excitation 和 inhibition of the 大脑. Are there good drugs 对于 epilepsy? 我们 know there are-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... not great drugs 对于 a lot of other conditions, 但-- 和 how 经常 does 一 need neurosurgery in order to treat epilepsy, 或 可以 it be treated most 经常 just using pharmacology?

Dr. Eddie Chang: Yeah. Great question. Well, a lot of 人们 have seizures 那 可以 be completely controlled by their medications, a lot. 但 there's 关于 一-third of 人们 who have epilepsy, which 我们 define as anyone who's had 三 或 更多 seizures, 那 关于 a third of them actually don't have control 与 all of the modern medications 那 我们 have nowadays. 和 some of the 数据 suggests 那 if 你 have 二 或 三 medications, it actually doesn't matter necessarily which of the anti-seizure medications it is, 但 there is 数据 suggests if 你've just tried 二 或 三, the fourth, fifth, sixth, 和 beyond is not 可能 to help control it. So, 我们 are in a situation, unfortunately, where a lot of the medications are great 对于 some 人们, 但 对于 another subset, they 可以't control it, 和 it comes 从 a particular part of the 大脑. Now, fortunately, in 那 subset, there's another part of 那 group 那 可以 benefit 从 a surgery 那 actually either removes 那 part of the 大脑, 和 nowadays 我们'll use stimulators now to sometimes put electrical stimulation in 那 part of the 大脑 to help 减少 the seizures.

安德鲁·休伯曼： 和 你 said a third of 人们 与 epilepsy 可能 need neurosurgery.

Dr. Eddie Chang: Well, what I mean by 那 is they continue to have seizures 那 are not controlled by all medications, 和 there's going to be another subset of 那些 那 may benefit 从 a surgery. It's probably not 那 whole third, it's a subset of 那. It's just to say 那 epilepsy 可以 be 确实 hard to get fixed, 和 对于 人们 where the seizures come 从 一 spot 或 an area, then surgery 可以 do great. If it comes 从 multiple areas 或 if it comes 从 the whole 大脑, then 我们 have to think 关于 other methods to control it. Fortunately, nowadays, there's actually other ways. Surgery now to us doesn't just mean removing part of the 大脑. Half of what 我们 do now is use stimulators 那 modulate the state of the 大脑 那 可以 help 减少 the seizures.

安德鲁·休伯曼： I've heard 之前 那 the ketogenic diet was originally formulated in order to treat epilepsy, 和 in particular in kids.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Is 那 true? 和 why 会 being in a ketogenic state 与 low 血液 glucose 减少 seizures?

Dr. Eddie Chang: 那's a great question. 和 to be honest, I don't know actually if it was originally designed to treat seizures. 但 I 可以 tell 你 对于 sure 那 对于 some 人们, just like 与 some medications, it 可以 be a life-changing thing. It 可以 completely change the way 那 the 大脑 works. 和 it's not something 那's 对于 everybody, 但 对于 some 人们, there's no question it has some 非常 beneficial effects. I think it's to be determined still why 和 how 那 works.

安德鲁·休伯曼： Yeah. I've heard 相似的 things 关于 the ketogenic diet 对于 人们 与 Alzheimer's dementia, 那 there's nothing particularly relevant 关于 ketosis to Alzheimer's per se, 但 因为 Alzheimer's changes the way 那 neurons metabolize 能量-

Dr. Eddie Chang: Mm-hmm

安德鲁·休伯曼： ... 那 shifting to an alternate fuel source 可以 sometimes make 人们 feel better, 和 so a number of 人们 are now trying it. 但 it's not as if 血液 glucose 和 having carbohydrates is causing Alzheimer's. 和 人们 get confused 经常 那 just 因为 something 可以 help doesn't mean 那 the opposite is harming somebody. So I find 这 确实 interesting. Sometime I'll check back 与 你 关于 what's happening in terms of ketogenic diets 和 epilepsy. 但 it 你 said 那 in some cases it 可以 help. Has 那 observation been made both 对于 children 和 对于 adults? 因为 I thought 那 originally the ketogenic diet 对于 epilepsy was 确实 对于 pediatric epilepsy.

Dr. Eddie Chang: Yeah, 那's right. So a lot of its 专注 has 确实 been on kids 与 epilepsy, 但 certainly it's a safe thing to try, so a lot of adults 会 try it as well.

安德鲁·休伯曼： Interesting. I'm curious 关于 epilepsy 对于 another reason. I was taught 那 epilepsy is an imbalance in the excitation 和 inhibition in the 大脑. So 你 think 关于 这些 electrical storms-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 那 give 人们 either grand mal shaking 和 kind of in convulsions.

Dr. Eddie Chang: Right.

安德鲁·休伯曼： 但 years ago, I was reading a book, a wonderful book actually, called Einstein in Love by Dennis Overbye. It was 关于 Einstein 和 his personal life. 人们 who knew him claim 那 he 会 sometimes walk along, 和 then every once in a while 会 just stop 和 kind of stare off 进入 space 对于 anywhere 从 a 分钟 to 三 to five 分钟.

Dr. Eddie Chang: Mm.

安德鲁·休伯曼： 和 it was speculated 那 he had absence seizures. What is an absence seizure? 和 the reason I ask is I occasionally 会 be walking along 和 I'll be thinking-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 关于 something 和 I'll stop, 但 in my 心智, I think I'm thinking 期间 那 time, 但 I realize 那 if I were to see myself 从 the outside, it 可能 appear 那 I was just kind of absent. What is an absence seizure? 因为 it's so strikingly 不同的 in its description 从, say, a grand mal convulsive seizure.

Dr. Eddie Chang: Sure. Well, like I mentioned 之前, depending on how the seizure activity spreads in the 大脑 或 how it actually propagates, if it stays in 一 particular spot 和 doesn't spread to the entire 大脑, it 可以 have 确实 不同的 manifestation. It 可以 represent 确实 differently. So absence seizure is just 一 category of 不同的 kind of seizures where 你 可以 lose consciousness, basically, 和 what I mean by 那 is 那 你're not fully aware of what's going on in 你的 environment, okay? So 你're sort of taken offline temporarily 从 consciousness, 但 你 could still be, 对于 example, standing. 和 to 人们 who are not paying 注意力, they may not even be aware 那 那's happening.

安德鲁·休伯曼： What are some other types of seizures?

Dr. Eddie Chang: Well, I think some of the other kinds are, the classic ones are temporal lobe seizures. So 这些 are ones 那 come 从 the medial structures like the amygdala 和 hippocampus. Oftentimes, 人们, when they have seizures coming 从 那, they may taste something 非常 unusual, like a metallic taste, 或 smell something like the smell of burning toast, something like 那. There are some 人们 与 temporal lobe seizures 会 have déjà vu. They 会 have 那 experience 那 你've been somewhere 之前. 但 那's just a precursor to the seizure. 和 it just highlights 那 when 人们 have seizures coming 从 这些 areas, they sometimes hijack what 那 part of the 大脑 is 确实 对于. So the amygdala 和 hippocampus, 对于 example, are 确实 重要 对于 learning 和 memory. It's not surprising 那 when 人们 have seizures there, 那 it 可以 evoke a feeling of déjà vu, 或 那 it 可以 evoke a feeling of anxiety. 和 the areas 那 are right next to it, 对于 example, 这些 areas are 确实 重要 对于 processing smell. So 这些 areas are right next to each other, so 你 可以 have 这些 kind of complex set of symptoms, the weird taste, the smell of toast, 和 then a feeling of déjà vu. 那's classic 对于 temporal lobe seizure, 和 it's 因为 那些 parts of the 大脑 那 process 那些 functions are right next to each other.

安德鲁·休伯曼： I'm told 那 I've had nocturnal seizures, 和 I've woken up sometimes 从 sleep having felt as if I was having a convulsion, the sort of sense of buzzing in the back of the head.

Dr. Eddie Chang: Mm.

安德鲁·休伯曼： 这 happened to me 二 或 三 times in college. Well, I woke up, 和 my girlfriend was 非常 distraught, like, "你 were having a seizure." I was having a full convulsion in my sleep. Is 那 correct? Is there such a thing as nocturnal seizures? What do they reflect? They eventually stopped happening, 和 I couldn't tether them to any kind of life event. I wasn't doing any kind of combat sport 或 anything at the time. I wasn't drinking alcohol much. It's 从不 确实 been my thing. What are nocturnal seizures 关于?

Dr. Eddie Chang: Oh, well-

安德鲁·休伯曼： 和 do I need 大脑 surgery?

Dr. Eddie Chang: Nocturnal seizures are just another form. Again, epilepsy 和 seizures 可以 have so many 不同的 forms, 和 not just where in the 大脑, 但 also when they happen. 和 there are some 人们 who, 对于 whatever reason, it's 非常 timed to the 昼夜节律.

安德鲁·休伯曼： Mm.

Dr. Eddie Chang: There's actually not just happening at 夜间, 但 a certain period at 夜间 when 人们 are in a certain stage of sleep 那 the 大脑 is in a state 那 it's vulnerable to having a seizure. 和 so 那's basically just 一 form of 那. Again, it's not just 关于 where it's coming 从, 但 also when it's happening 和 how 那's timed 与 other things 那 are happening 与 the 身体.

安德鲁·休伯曼： Interesting. Well, it eventually stopped happening, so I stopped worrying 关于 it.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 但 I haven't had seizures since. Returning to speech 和 language, when I was getting weaned in neuroscience, I learned 那 我们 have an area of the 大脑 对于 producing speech, 和 我们 have an area of the 大脑 对于 comprehending speech.

Dr. Eddie Chang: Mm-hmm.

安德鲁·休伯曼： What's the story there? Is it still true 那 我们 have a Broca's 和 a Wernicke's area? 那些 are names of neurologists, presumably, 或 neurosurgeons-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 那 discovered 这些 不同的 大脑 areas. Maybe 你 could familiarize us 与 some of the sort of textbook version of how speech 和 language are organized in the 大脑, maybe share 与 us a little bit of the lesion 研究 那 led to 那 understanding, 和 then I 会 love to hear a bit 关于 what 你的 laboratory is discovering 关于 how things are actually organized, 因为 从 some discussions 你 和 I have had over the last year 或 so, it seems like... Well, let's just be blunt. It seems 那 much of what 我们 know 从 the textbooks could be wrong.

Dr. Eddie Chang: Well I love 那 question 因为 对于 me, it's 非常 central to the 研究 我们 do, 和 it's where the intersection between what 我们 do in the laboratory 和 我们的 研究 interfaces 与 what I see in patients. 和 一 of the things 那 fascinated me early on in my medical 训练 was in doing some of 这些 大脑 mapping 或 watching them 与 my mentor 或 taking care of patients 那 had 大脑 tumors in a certain part of the 大脑, was 那 a lot of times what I was seeing in a patient did not correlate 与 what I was taught in medical school. 和 some 人们 会 think, well, 这 可能 be an exception. 但 之后 你 see it 对于 a couple of times, 和 if 你're kind of interested in 这 problem, it poses a serious challenge to what 你've learned 和 how 你 think 关于 how 这些 things operate. 和 那 actually got me 确实 interested in trying to figure 这 out 因为 earlier 我们 talked 关于 just 这 extraordinary thing 那 the 大脑 is doing to create words 和 sentences, 和 那's the process by which I'm getting ideas out 从 my 心智 进入 yours. It's an incredible thing, right? It's the basis of communication, high information communication between 二 个体 那's 确实 unique to humans. So in historical times, how 这 works has been 非常 controversial 从 天 一 of neuroscience. A long time ago, 人们 thought the bumps on 你的 head corresponded to the 不同的 faculties of the 心智. So, 对于 example, if 你 had a bump here, it 可能 be corresponding to intelligence 或 another 一 over here to vision 和 这些 kind of things. 那's what 我们 nowadays call phrenology 和 那 was kind of the starting point. A lot of 那 has been, of course, debunked, 但 when 你 see 那些 little statues of 不同的 大脑 partitions on someone's head, 那's 本质上 how 人们 were thinking 关于 how the 大脑 worked back then, a couple of hundred years ago. Modern neuroscience began when-- actually, it was 非常 much related to the discovery of language. So modern neuroscience meaning moving beyond 这 idea 那 the bumps on the scalp corresponded to the faculties of the 心智. 但 there were things 那 actually were in the 大脑 themselves, 和 they weren't corresponding to things 那 你 could see superficially, like on the scalp 或 externally. 那 it was something 关于 the 大脑 itself. It seems so obvious now, 但 back then, 这 was the big academic debate. 和 the 首先 observation 那 I think 确实 was 确实 impactful in the area of language was an observation by a French neurosurgeon named Pierre Broca. 和 what he observed was 那 in a patient, not 那 he did surgery, 但 那 he had seen 和 taken care of, 那 the person couldn't talk. 和 in particular, they called 这 individual Tan 因为 the only words 那 he could produce was Tan. 对于 the most part, he could generally understand the kind of things 那 人们 were asking him 关于, 但 the only thing 那 he could utter 从 his mouth were 这些 words, Tan. 和 what eventually had happened was 这 individual passed away, 和 the way 那 neuroscience was done back then was basically to wait until 那 happened 和 then to remove the 大脑 和 to see what part of the 大脑 was affected in 这 patient 那 they called Tan. 和 what Broca found was 那 there was a part in the left frontal lobe. So the frontal lobe is 这 area like I described earlier, which is up behind 我们的 forehead, up here. 和 in the back of 那 frontal lobe, he claimed 那 这 was the seat of articulation in the 大脑. He literally used something like 那 in French, the seat of articulation, meaning 那 这 is the part of the 大脑 那 is responsible 对于 us to generate words. 关于 50 years later, the story becomes 更多 complicated 与 a German neurologist named Carl Wernicke. 和 what Wernicke described was a 不同的 set of symptoms in patients 那 he observed, a 不同的 phenomenon where 人们 could produce words, 和 they were fluent in the sense 那 they sound like they could be real words, 但 从 a 不同的 language, 对于 example. 和 some of us call 那 word salad 或 jargon. It's 本质上 they were making up words, 但 it was not intentional. It's just the way 那 the words came out. 但 in addition to 那, he observed 那 这些 人们 also could not understand what was being said to them. So, 我们 could be having a conversation 和 I'd be asking 你, "Am I a woman?" 和 你 可能 nod 你的 head, just 因为 你're not processing the question. 和 so, here are 二 observations. 一 is 那 the frontal lobe is 重要 对于 articulating speech, creating the words, 和 expressing them fluently. 和 then a 不同的 part of the 大脑 called the left temporal lobe, which is 这 area right above my ear. 那 is an area 那 I think was claimed to be 确实 重要 对于 understanding So the 二 major functions in language, to speak 和 to understand, were kind of pinned down to 那. 和 我们've had 那 basic idea in the textbooks 对于 over 200 years.

安德鲁·休伯曼： Certainly what I was taught.

Dr. Eddie Chang: Is 那 right?

安德鲁·休伯曼： Oh, every-- Yeah. 和 certainly 我们 still teach-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... undergraduates, graduate students, 和 medical students 那.

Dr. Eddie Chang: Well, 那's what I learned, too, in medical school. 和 what I saw in reality when I started taking care of patients was 那 it's not so simple. In fact, part of it is fundamentally wrong. So just in a nutshell, nowadays, 之后 looking at 这 非常 carefully over hundreds of patients, 我们've shown 那 surgeries, 对于 example, in the posterior part of the frontal lobe, a lot of times 人们 have no problem talking at all whatsoever 之后 那些 kind of surgeries. 和 那 it's a 不同的 part of the 大脑, what 我们 call the precentral gyrus. The precentral gyrus is a part of the 大脑 那 is intimately associated 与 the motor cortex. The motor cortex is the part of the 大脑 那 has a map of 你的 entire 身体, so 那 it has a part 那 corresponds to 你的 feet, it has a part 那 corresponds to 你的 hands. 但 then there's another part 那 comes out 更多 laterally on the side of the 大脑 那 corresponds to 你的 lips, 你的 jaw, 你的 larynx. 和 我们 have seen 那 when patients have surgeries 或 injuries to 那 part of the 大脑, it actually 可以 确实 interrupt language. So it's not as simple as just moving the 肌肉 of the vocal tract, 但 it's also 重要 对于 formulating 和 expressing words. So 那's Broca's area 那 I think the field now recognizes, not just 因为 of 我们的 work, 但 many other 人们 那 have studied 这 in stroke 和 beyond, is 那 the idea 那 那 is the basis of speaking in Broca's area is fundamentally wrong right now. 和 我们 have to figure out how to correct the textbooks 那 我们 kind of understand 那 so 那 我们 可以 continue to make progress. Now, in terms of the other major area 那 我们 call Wernicke's area, in the posterior temporal lobe, 那 has held, I think, quite legitimately 对于 some time. So 那 is an area 那 你 have to be super careful when 你 do surgery there. 那's an area where if 你 have a mistake there 和 你 cause a stroke 或 你 remove too much of the tumor there, 你 go too far beyond it, then the person 可以 be 确实, 确实 hurt. They'll have a condition 那 我们 call aphasia, where they may not be able to understand words, they may not be able to remember the word 那 they're trying to say. They know what they're trying to say, 但 they 可以't remember the precise word 那 goes 与 the object 那 they're trying to think of. They may even produce words 那 I described 之前 are like word salad 或 非常 jargony. So they 可能 say something like, "Tamirani." 那's not a real word, 但 it sounds like it could be. 和 那's just 因为 那 part of the 大脑 has some role not just in understanding what 我们 hear, 但 also actually has a 确实 重要 role in sending the commands to 不同的 parts of the 大脑 to control what 我们 say.

安德鲁·休伯曼： Not long ago, 你 和 me 和 my good friend Rick Rubin were having a conversation 关于 medicine 和 science, 和 Rick asked the question, "What percentage of what 你 learned in graduate 和/或 medical school do 你 think is correct?" 和 你 had a 非常 interesting answer. 会 你 share it 与 us?

Dr. Eddie Chang: I don't know. I don't remember the exact, 但 I 会 say 那 与 regard to the 大脑 in particular, I 会 say 关于 50% gets it right 和 accurate 和 is helpful. 但 another 50% is just the approximation 和 oversimplification of what's going on. The example 那 我们 talked 关于, language, is just an example of 那. It's just there are things 那 make it easier to learn 和 easier to teach 和 easier to even think 关于. 和 那's probably why 我们 continue teaching in the way 那 我们 do. 但 I think as time goes on, the complexity of reality of how the 大脑 works is well, 首先 of all, 我们're still trying to figure it out. 和 秒 of all, it is complex, 和 it's still incomplete story.

安德鲁·休伯曼： It's early 天, 和 我们'll get 进入 some of the technical advances 那 are allowing some correction of the errors 那 the field has made. 和 look, no disrespect to the 大脑 explorers 那 came 之前 us, 和 the ones 那 come 之后 us 会 correct us, right? 那's the way the game is played. 但 what I'm hearing is 那 there are certain truths 那 人们 accept, 和 then there's 关于 half of the information 那 is still open 对于 debate 和 maybe even 对于 complete revision. 一 thing 那 I learned 关于 language 和 the neural 回路 underlying language is 那 it's heavily lateralized, 那 这些 structures, Broca's 和 Wernicke's 和 other structures in the 大脑 responsible 对于 speech 和 comprehension of speech, sit mainly on 一 side of the 大脑, 但 they do not have a mirror representation 或 another equivalent area on the opposite side of the 大脑. 和 对于 那些 那 haven't poked 大约 in a lot of brains, certainly 你, Eddie, have done far 更多 of 那 than I have, 但 I've done my fair share in non-human species 和 a little bit in humans. Almost every structure has a matching structure on the other side of the 大脑. So when 我们 say the hippocampus, 我们 确实 mean 二 hippocampi, 一 on each side of the 大脑. 但 language, I was taught, is heavily lateralized. 那 is, 那 there's only 一. So 那 raises 二 questions. 一, is 那 true? 和 if it is true, then what is the equivalent real estate on the opposite side of the 大脑 doing?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： If it's not doing the same function 那 the 一 on the, say, the left side is performing.

Dr. Eddie Chang: Well, 那's 一 of 那些 things 那 is, again, mostly true, not 100%. 和 what I mean by 那 is 那 it's complicated. So 对于 人们 who are right-handed, 99% of the time, the language part of the 大脑 is on the left side.

安德鲁·休伯曼： 和 what is the equivalent 大脑 area on the right side doing if it's not doing language?

Dr. Eddie Chang: Well, the thing 那's incredible is if 你 look at the right side 和 你 look at it 非常 carefully, either under an MRI 或 你 actually look at the 大脑 under slides at a microscope, it looks 非常, 非常 相似的. It's not identical, 但 it looks 非常, 非常 相似的. All the gyri, which are the bumps on the 大脑 那 have the 不同的 contours, 和 the valleys 那 我们 call sulci, 那些 all look basically the same, like there is a mirror anatomy on the left 和 right side. 和 so it's not been so clear what's so special actually 关于 the left side to house language. 但 what 我们 do know, 和 这 is what 我们 use all the time in assessing 和 figuring out 这 之前 surgery, is if 你're right-handed, 99% of the time the language is going to be on the left side of the 大脑.

安德鲁·休伯曼： Is handedness genetic in any way?

Dr. Eddie Chang: Yes.

安德鲁·休伯曼： When I grew up, a pen 或 a pencil 或 a crayon was placed 进入 my hand, presumably, 或 I started using... My father was left-handed, 和 then where he grew up in South America, they forced him to force himself to become right-handed. They actually used to restrict the movement of his left hand, so he was forced to write. 和 then 你 have hook lefties-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 和 hook righties.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： I know 这 is a deep dive, 和 我们 probably don't want to go 进入 every derivation of 这. 但 so 对于 somebody who's left-handed, naturally just starts writing 与 the left hand, there's some genetic predisposition to being left-handed?

Dr. Eddie Chang: Absolutely. No question 关于 it. Handedness is not entirely, 但 strongly genetic. So there is something 那 ties all of 这. 和 what does handedness, 对于 example, have to do 与 where the part of 你的 大脑 那 controls language? Well, it turns out 那 the parts 那 control the hand are 非常 close to the areas 那 确实 are responsible 对于 the vocal tract. Again, part of the motor cortex 和 part of 这 大脑 area called the precentral gyrus. 和 there are some theories 那 因为 of their proximity, 那 这些 parts of the 大脑 可能 develop together early in utero, 和 they 可能 have a head start compared to the right side. 和 因为 they have a head start, 那 things solidify there. 这 is 一 theory of why 这 happens. In 人们 who are left-handed, it still turns out 那 the vast majority of 人们 have language on the left side, 但 it's not 99%, it's 更多 like 70%. So if 你're left-handed, it's still 更多 可能 那 the language part of 你的 大脑 is going to be on the left side, 但 there's going to be a greater proportion, maybe 20%, 30%, where it's either in both hemispheres 或 on the right side. 和 just to make 这 a little bit 更多 interesting is 那 when 人们 have strokes on the left side, 和 if they're lucky enough to recover 从 那些 strokes, sometimes 那 involves reorganization, 这 term 那 我们 called plasticity earlier, where the areas 大约 where the stroke take on 那 new function in a way 那 they didn't have 之前. 那 可以 certainly happen in the left hemisphere. 但 there are also instances where the right hemisphere 可以 also start to take on the function of language, when it was once on the left 和 then transfers to the right. So the thing 那 I think 关于 a lot is 那 the machinery probably exists on both sides, 但 我们 don't use them together all the time. In fact, 我们 may strongly bias 一 side 或 the other, just like 我们 use 我们的 二 hands in 非常, 非常 不同的 ways. It's a little bit the same 与 the 大脑. Well, it's 因为 of what 我们 do 与 the 大脑 那 actually is why 我们 use the hands in 不同的 ways. 和 the same thing goes 对于 language, which is, again, the substrates, the organ, the language organ, the part of the 大脑 那 process it probably has 非常 相似的 machinery on the left side as the right, 和 the right may have the capability to do it. 但 in real everyday use, the 大脑 specializes 一 of the sides in order 对于 us to use it functionally. 那's a theory.

安德鲁·休伯曼： 你're bilingual, correct?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 你 speak English 和 Chinese?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 对于 人们 那 are bilingual 和 那 learn 二 或 更多 lang-- well, bilingual is 二, obviously, 但 learn both languages 或 let's say 更多 languages 从 an early time in life, do they use the same 大脑 area to generate 那 language? 或 perhaps they use the left side to speak English 和 the right side to speak Chinese? Do 我们 know anything 关于 bilingualism in the 大脑?

Dr. Eddie Chang: I think 我们 know a lot 关于 bilingualism in the 大脑. The answers are still out there, the final answers on it, 和 part of the answer is yes, absolutely, 我们 use some parts of the 大脑 非常 similarly. 我们 actually have a 研究 in the lab right now where 我们're looking at 这, where 人们 who speak 一 language 或 another 或 bilingual, 和 我们're looking at how the 大脑 activity patterns occur when they're hearing 一 language versus the other. 和 what's striking to see, actually, is how overlapping they 确实 可以 be, even though the person may have no idea of the language 那 they're hearing, the English part of the 大脑 is still processing 那 和 maybe trying to interpret it 通过 an English lens, 对于 example. So the short answer is 那 与 bilingualism, there are shared circuitry. There's 这 shared machinery in the 大脑 那 allows us to process both. 但 it's not identical. It's the same part of the 大脑, 但 what it's doing 与 the signals 可以 be 非常 不同的. 和 what I mean by 那 precisely is not the instantaneous detecting of 一 sound to the next, 但 the memory of the sequences of 那些 particular sounds 那 give rise to things like words 和 meaning. 那 可以 be highly variable 从 一 individual to the next, 和 那些 neurons are 非常 sensitive to the sequences of the sounds, even though the sounds themselves 可能 have some overlap between languages.

安德鲁·休伯曼： Fascinating. Okay, so 我们've talked 关于 大脑 areas 和 a little bit 关于 lateralization. I want to get back to the hands 和 some things related-

Dr. Eddie Chang: Right

安德鲁·休伯曼： ... to emotion in a little bit. 但 maybe now 我们 could go 进入 那些 大脑 areas-

Dr. Eddie Chang: Okay

安德鲁·休伯曼： ... 和 start to ask the question: what exactly is represented 或 mapped there? 和 对于 人们 who perhaps aren't familiar 与 大脑 mapping 和 representation in receptive fields, perhaps the simplest analogy 可能 be the visual 系统, where I look at 你的 face, I know 你, I recognize 你, 和 certainly there are 大脑 areas 那 are responsible 对于 face recognition. 但 the fact 那 I know 那 那's 你的 face, 和 对于 那些 listening, I'm looking at Eddie's face. The fact 那 I know 那 那's 你的 face at all is 因为 我们 are well aware 那 there are cells 那 represent edges 和 那 represent dark 和 light, 和 那些 all combine in what 我们 call a hierarchical structure. They sort of build up 从 basic elements as simple as little dots, 但 then lines 和 things 那 move, et cetera, to give a coherent representation of the face. When I think 关于 language, I think 关于 words 和 just talking. If I sit down to do a long podcast 或 I think 关于 asking 你 a question, I don't even think 关于 the words I want to say 非常 much. I have to think 关于 them a little bit, 一 会 hope. 但 I don't think 关于 individual syllables unless I'm trying to accent something, 或 it's a word 那 I have a particular difficulty saying, 或 I want to change the cadence, et cetera. So what's represented in the neurons, the nerve cells in 这些 areas? Are they representing vowels, consonants? 和 how do things like inflection, like I occasionally 会 poke fun at upspeak.

Dr. Eddie Chang: Mm.

安德鲁·休伯曼： 但 there's, I think, a healthy, a normal version of upspeak where somebody's asking a question. Like 对于 instance, "What is 那?" 那's an appropriate use of upspeak, as opposed to saying something 那 is not a question 和 putting a lilt at the end of the sentence. Then 我们 call 那 upspeak, which doesn't fit 与 what the person is saying. So what in the world is contained in 这些 大脑 areas? What is represented, to me, is perhaps 一 of the most interesting questions, 和 I know 这 lands square in 你的 wheelhouse.

Dr. Eddie Chang: Sure. Let's get 进入 这, Andrew, 因为 这 is 一 of the most exciting stuff 那's happening right now, is understanding how the 大脑 processes 这些 exact questions. 和 你 asked me earlier, what is the difference between speech 和 language? Speech corresponds to the communication signal. It corresponds to me moving my mouth 和 my vocal tract to generate words, 和 你're hearing 这些 as an auditory signal. Language is something much broader. So it refers to what 你're extracting 从 the words 那 I'm saying. 我们 call 那 pragmatics, 和 sort of are 你 getting the gist of what I'm saying? There's another aspect of it 那 我们 call semantics. Do 你 understand the meaning of 这些 words 和 the sentences? There's another part 那 我们 call syntax, which refers to how the words are assembled in a grammatical form. So 那些 are all 确实 critical parts of language, 和 speech is just 一 form of language. There's many other forms, like sign language, reading. 那些 are all 重要 modalities 对于 reading. 我们的 研究 确实 focuses on 这 area 那 我们're calling speech. Again, the production of 这 audio signal, which 你 可以't see, 但 你的 microphones are picking up. There are 这些 vibrations in the 空气 那 are created by my vocal tract 那 are picked up by the microphone, in the case of 这 recording, 但 also picked up by the sensors in 你的 ear. The 非常 tiny vibrations in 你的 ear are picking 那 up 和 translating 那 进入 electrical activity. 和 what the ear does at the periphery is translates all sounds 进入 不同的 frequencies. So its main thing to do is to take a speech signal 或 any other kind of sound 和 decompose it, meaning separate 那 sound 进入 不同的 kind of signals. 和 in the case of hearing, what it's doing is separating it out 进入 low, middle, high frequencies at a 非常 high resolution. It's doing it 非常 quickly, 和 it's doing it in a 确实 fine way to separate all of 那些 不同的 sounds. So if 你 look at the periphery near the nerve 那 goes to 你的 ear, 那些 nerve fibers, some of them are tuned to low frequency, some of them are tuned to high frequency, some of them are tuned to the middle frequencies. 和 那 is what 你的 ear is doing. It's taking 这些 words 和 splitting them up 进入 不同的 frequencies.

安德鲁·休伯曼： 和 对于 那些 of 你 out there 那 aren't familiar 与 thinking 关于 things in the so-called frequency space, bass tones 会 be lower frequencies 和 high-pitched tones 会 be higher frequencies, just to make sure everyone's on the same page. So the sound of my voice, the sound of 你的 voice, 或 any sound in the environment is being broken down 进入 这些 frequencies. Are they being broken down 进入 非常 narrow channels of frequency, 或 are they, I want to avoid nomenclature here, 或 are they 或 are they being binned as fairly broad frequencies? 因为 我们 know low, medium, 和 high, 但 对于 instance, I 可以 detect whether 或 not something's approaching me 或 moving away 从 me, depending on whether 或 not it sweeps louder 或

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... towards 或 away. It's subtle, 和 of course, it's combined 与 what I see 和 my own movement, 但 how finely sliced is 我们的 perception of the auditory world?

Dr. Eddie Chang: Oh, extraordinarily precise. 我们 take 这些 millisecond cues, the millisecond differences between the sound coming to 一 ear, let's say 你的 right ear versus 你的 left, to understand what direction 那 sound came 从. 那些 are only millisecond differences, 和 那's how precise 这 works. 但 on the other hand, it does a lot of computation on 这. It does a lot of analysis as 你 go up, 和 a lot of 我们的 work is focused on the part of the 大脑 那 我们 call the cortex. The cortex is the outermost part of the 大脑 where 我们 believe 那 sounds are actually converted 进入 words 和 language. So there's 这 transformation where at the ear, words are decomposed 和 turned 进入 这些 elemental frequency channels, 和 then as it goes up 通过 the auditory 系统, hits the cortex. There are some things 那 happen, obviously, 之前 it gets to the cortex. 但 when it gets to cortex, there's something special going on, which is 那 那 part of the 大脑 is looking 对于 具体的 sounds. 和 specifically, what I mean by 那 is the sounds of human language, so the ones 那 are the 不同的 consonants 和 vowels in a 不同的 language. 一 of the ways 那 我们 have studied 这 is looking in patients who have epilepsy, 和 in a lot of 这些 cases where the MRI looks completely normal, 我们 have to put electrodes surgically on a part of the 大脑. The temporal lobe is a 非常, 非常 common place. So 我们've done a lot of 我们的 work looking at how the temporal lobe processes speech sounds 因为 我们're looking 对于 where the seizures start, 但 then 我们're also doing 大脑 mapping 对于 language 和 speech so 我们 可以 protect 那些 areas. 我们 want to identify the areas 那 我们 want to remove to cure someone's seizures, 但 我们 also want to figure out the areas 那 are 重要 对于 speech 和 language to protect 那些 so 那 我们 可以 do a surgery 那's effective 和 safe. 和 so in 我们的 研究, 和 why it's become a 确实 重要 addition to 我们的 knowledge, is 那 我们 have electrodes directly recording 从 the human 大脑 surface. A lot of technology 我们 work 与 right now is recording on the order of millimeters, 和 they 可以 record millisecond time resolution of neural activity. 和 what 我们 see is extraordinary patterns of activity when 人们 hear words 和 sentences. If 你 look at 那 part of the 大脑 那 我们 call Wernicke's area, in 这 part of the temporal lobe, 这 whole area lights up when 你 hear words 或 speech. 和 it's not in a way 那 is like a general light bulb warming up 和 it's generally lit up, 但 what 你 actually see is something much, much 更多 complicated, which is a pattern of activity. 和 what 我们've done in the last 10 years is try to understand what does 那 pattern come 从, 和 if 我们 were to look at each individual site 从 那 part of the 大脑, what 会 我们 see? What parts of words are being coded by electrical activity in 那些 parts of the 大脑? Remember, the cortex is using electrical activity to transmit information 和 do analysis, 和 what 我们're doing is 我们're eavesdropping on 这 part of the 大脑 as it's processing speech to try to understand what each individual site is doing.

安德鲁·休伯曼： 和 what are 那些 sites doing? 或 could 你 give us some examples of what 那些 sites are doing? So 对于 instance, are they sites 那 are 具体的 对于, 或 我们 could say even listening 对于 consonants 或 对于 vowels 或 对于 inflection 或 对于 emotionality? What's in there?

Dr. Eddie Chang: Okay, well-

安德鲁·休伯曼： What makes 这些 cells fire?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Yeah.

Dr. Eddie Chang: What gets them excited-

安德鲁·休伯曼： Yeah

Dr. Eddie Chang: ... what gets them going is hearing speech. In particular, there are some of 这些 确实 focal sites, again, just on the order of a millimeter 或 at some 水平, single neurons, 那 are tuned to consonants. Some are tuned to vowels. Some are tuned to particular features of consonants. What I mean by 那 are 不同的 categories of consonants. There's a class of consonants 那 我们 call plosive consonants. There's a little bit of linguistic jargon, 但 I'm going to make a point here 与 那, is 那 certain classes of sounds, when 你 make them, it requires 你 to actually close 你的 mouth temporarily.

安德鲁·休伯曼： Now I'm going to be thinking 关于 这. So plosive, like saying the word plosive requires 那.

Dr. Eddie Chang: Exactly. So what's cool 关于 那 is 那 我们 actually have no idea what's going on in 我们的 mouth when 我们 speak. 我们 确实 have no idea.

安德鲁·休伯曼： Some 人们 definitely have no idea.

Dr. Eddie Chang: Yeah. Well, not just in terms of what 你're saying sometimes-

安德鲁·休伯曼： Sure

Dr. Eddie Chang: ... 但 actually how 你're actually moving-

安德鲁·休伯曼： Right

Dr. Eddie Chang: ... the 不同的 parts of vocal tract. 和 I have a feeling if 我们 actually required understanding, 我们 会 从不 be able to speak 因为 it's so complex. It's such a complex feat. Some 人们 会 say it's the most complex motor thing 那 我们 do as a species, is just speaking. Not the extreme feats of acrobatics 或 athleticism, 但-

安德鲁·休伯曼： Oh, 和 尤其是-

Dr. Eddie Chang: ... just speaking

安德鲁·休伯曼： ... well, 和 尤其是 when 一 observes opera 或 人们 who, freestyle rappers. 和 of course, it's not just the lips, it's the tongue.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 和 你've mentioned 二 Other structures, pharynx 和 larynx are the main ones 那 the-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... 可以 你 tell us, just educate us at a superficial 水平 what does pharynx 和 larynx do differentially? 因为 I think most 人们 aren't going to be familiar 与 那.

Dr. Eddie Chang: Okay, sure. So I'll talk primarily 关于 the larynx here 对于 a 秒, which is 那 if 你 think 关于 when 我们're speaking, 确实 what 我们're doing is 我们're shaping the breath. So even 之前 你 get to the larynx, 你 got to start 与 the expiration. So 我们 fill up 我们的 lungs, 和 then 我们 push the 空气 out. 那's a normal part of breathing. 和 what is 确实 amazing 关于 speech 和 language is 那 我们 evolved to take advantage of 那 normal physiologic thing at a larynx. 和 what the larynx does is 那 when 你're exhaling, it brings the vocal folds together. Some 人们 call them vocal cords. They're not 确实 cords, they're 确实 vocal folds. They're 二 pieces of 组织 那 come together, 和 a 肌肉 brings them together. 和 then what happens is when the 空气 comes 通过 the vocal folds, when they're together, they vibrate, at 确实 high frequencies, like 100 to 200 hertz. Yours is probably 关于 100 hertz. The average-

安德鲁·休伯曼： Whereas yours is 200 .

Dr. Eddie Chang: No. Most male voices are 大约 100, okay? 和 then the average female voice is 大约 200 hertz.

安德鲁·休伯曼： Oh, 和 as 你 know, I've 总是 had the same voice.

Dr. Eddie Chang: Yes.

安德鲁·休伯曼： 这 was a point of shame when I was a kid. Folks, my voice 从不 changed. I 总是 had the same voice. 这 is a discussion 对于 another time.

Dr. Eddie Chang: Yeah. Well, it's a great voice, a great baritone voice. 但 I know in 你的 voice, it's a low-frequency voice, 和 the reason why men 和 women generally have 不同的 voice qualities is it has to do 与 the size of the larynx 和 the shape of it. Okay, so in general, men have a larger voice box 或 larynx, 和 the vibrating frequency, the resonance frequency of the vocal folds when the 空气 comes 通过 them is 关于 100 hertz 对于 men 和 关于 200 对于 women. So what happens is, okay, so 你 take a breath in, 和 then as the 空气 is coming out, the vocal folds come together, 和 the 空气 goes 通过. 那 creates the sound of the voice 那 我们 call voicing, 和 那's the 能量 of 你的 voice. It's not just 你的 voice characteristic, it's the 能量 of 你的 voice is coming 从 the larynx there. It's a noise. 和 then it's the source of the voice. 和 then what happens is 那 能量, 那 sound goes up 通过 the parts of the vocal tract, like the pharynx, 进入 the oral cavity, which is 你的 mouth 和 你的 tongue 和 你的 lips. 和 what 那些 things are doing is 那 they're shaping the 空气 in particular ways 那 create consonants 和 vowels. So 那's what I mean by shaping the breath. It just starts 与 这 exhalation. 你 generate the voice in the larynx, 和 then everything above the larynx is moving 大约, just like the way my mouth is doing right now, to shape 那 空气 进入 particular patterns 那 你 可以 hear as words.

安德鲁·休伯曼： Fascinating, 和 immediately makes me wonder 关于 更多 primitive 或 non-learned vocalizations, like crying 或 laughter. Babies 会 cry, babies 会 show laughter. Are 那些 sorts of vocalizations produced by the language areas, like Wernicke's, 或 do they have their own unique neural structures?

Dr. Eddie Chang: Yeah, interesting question. So 我们 call 那些 vocalizations. A vocalization is basically where someone 可以 create a sound, like a cry 或 a moan, 那 kind of sound, 和 it also involves the exhalation of 空气. It also involves some phonation at the 水平 of the larynx where the vocal folds come together to create 那 audible sound. 但 it turns out 那 那些 are actually 不同的 areas. So 人们 who have injuries in the speech 和 language areas oftentimes 可以 still moan. They 可以 still vocalize, 和 it is a 不同的 part of the 大脑. I 会 say an area 那 even non-human primates have 那 可以 be specialized 对于 vocalization. It's a 不同的 form of communication than words, 对于 example.

安德鲁·休伯曼： The intricacy of 这些 回路 in the 大脑 和 their connections to the pharynx 和 larynx, it's almost overwhelming in terms of thinking 关于 just how complicated it must be, 和 yet some general features 和 principles are starting to emerge 从 你的 work 和 从 the work of others. If 我们 think 关于 那 work 和 我们 think 关于, 对于 instance, Wernicke's area, if I were to record 从 neurons in Wernicke's area at 不同的 locations, 会 I find 那 there's any kind of systematic layout? 对于 instance, in terms of, 我们 talked 关于 sound frequency. 我们 know 那 low frequencies are represented at 一 end of a structure 和 high frequencies at the other. 这 is true actually, at least 从 my earlier 训练, within the ear itself, within the cochlea. The early work of von Bekesy 和 从 cadavers, right? They actually figured 这 out 从 dead 人们, which is incredible. A fascinating literature 人们 应该 look up. 和 in the visual 系统, 我们 know 那, 对于 instance, visual position, where things are, is mapped systematically. In other words, neurons 那 sit next to each other in the 大脑 represent portions of visual space 那 are next to each other in the real world. What is the organization of language in areas like Wernicke's 和 Broca's? 对于 instance, I think of the vowels, A, E, I, O, U As a kind of a coherent unit, 但 do I find the A neurons are next to the E neurons 或 next to the-- 或 the A, E, I, O, U, is 那 vowel representation also laid out in order, 或 is it kind of salt 和 pepper? Is it random?

Dr. Eddie Chang: 那's been 一 of the most 重要 questions 我们've been trying to answer 对于 the past decade. So there is a part of the 大脑 那 我们 call the primary auditory cortex, 和 the primary auditory cortex is deep in the temporal lobe. 和 if 你 looked at 那 part of the 大脑, there is a map of 不同的 sound frequencies. So if 你 look at the front of 那 primary auditory cortex, 你'll find low-frequency sounds. 和 then as 你 march backwards in 那 cortex, it goes 从 low to medium to high frequencies. It's organized in 这 确实 nice 和 orderly way. 和 it turns out there's just not just 一, there's mirrors of 那 tone frequency map in the primary auditory cortex. The areas 那 are 确实 重要 对于 speech are on the side of 那. 和 我们 now think 那 speech 可以 go straight to the speech cortex 没有 having to go 通过 the primary auditory cortex, 那 it has its own 通路 to get to the part of the 大脑 那 processes speech. 和 when 我们've looked at 那 question 关于 is there a map, the short answer is yes, there is a map. 但 it is not structured universally across all 人们 in a way 那 我们 可以 clearly see right now. It is like a salt 和 pepper map of the 不同的 features in speech. So 之前 我们 talked 关于 这些 sounds 那 are called plosives. 你 make a plosive when the mouth 或 something in the oral cavity closes temporarily. 和 when it opens, 那 creates 那 fast plosive sound. So when 你 say dad 或 the ball, like the V in ball, 那 kind of thing, 你 会 notice 那 你的 lips actually close, 和 then it's the 释放 of 那 那 creates 那 particular sounds. Okay, so 那些 are the sounds 那 我们 call plosive. 那些 are like badaga, pataka. 那些 are a certain class of consonants 那 我们 call plosive sounds. There's another class of sounds 那 我们 call fricatives in linguistics. Fricatives are created by turbulence in the airstream as it comes out 通过 the mouth. 和 the way 那 我们 make 那 turbulence is getting the mouth 和 the lips to close almost until they're completely shut. 或 putting the tongue to near the teeth to almost get it completely shut, 但 just have a narrow aperture. 那 creates a turbulence in the airflow 那 我们 perceive as a high-frequency sound. So 那些 are the sounds like sha 和 tha, 那些 kind of things. If 你 look at the frequencies, they're higher frequencies, 和 那些 are created by 具体的 movements 那 你 constrict the airflow to create turbulence, 和 我们 hear it as sha, sa, tha.

安德鲁·休伯曼： So if I say 那.

Dr. Eddie Chang: Exactly.

安德鲁·休伯曼： 和 as opposed to a plosive where I'd say explosive.

Dr. Eddie Chang: Right.

安德鲁·休伯曼： Now, of course, I'm emphasizing here.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Well, 这 explains something 和 solves a mystery, which is recently I've been fascinated by the work of a physician scientist back east, Dr. Shanna Swan, who's done a lot of work on things 那 are contained in pesticides 和 foods 那 are changing 激素 水平, 和 she refers to phthalates-

Dr. Eddie Chang: Mm-hmm

安德鲁·休伯曼： ... which is spelled P-- So it's both a plosive 和-

Dr. Eddie Chang: Yeah

安德鲁·休伯曼： ... a tha.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： So it's combining the 二, 和 it's 一 of the most difficult words in the English language to pronounce, 秒 only perhaps to the correct pronunciation of ophthalmology.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： So it's a combination of a plosive 和 一 of 这些 tha sounds, 和 那's probably why it's difficult.

Dr. Eddie Chang: 那's exactly right. In fact, 我们 have a term 对于 那. 那's called a consonant cluster. So sometimes syllables 会 just have 一 consonant. 但 when 我们 start stacking certain syllables in a sequence, 和 there's rules 那 actually govern which consonants 可以 be in a particular sequence 对于 a given language, 那 makes it 更多 complicated. 和 certain languages have a lot 更多 consonant clusters than others.

安德鲁·休伯曼： 对于 instance?

Dr. Eddie Chang: So 对于 instance, Russian, 对于 example, has a lot of consonant clusters. English has a lot of them. There are other languages 那 have 非常, 非常 few. 对于 example, Hawaiian. Hawaiian has an inventory of 关于 12 to 14 不同的 phonemes, 14 不同的 consonants 和 vowels. English, on contrast, has 关于 40 不同的 consonants 和 vowels. So languages have 不同的 inventories. They 可以 overlap 对于 sure, 但 不同的 languages use 不同的 sound elements, combine 和 recombine 那些 elements to give rise to 不同的 words 和 meanings.

安德鲁·休伯曼： 可以 我们 say 那 there is a most complicated language out there, 或 among the most complicated, 会 it be Russian?

Dr. Eddie Chang: It's definitely high up there. English is up there, too, actually. Yeah, German as well.

安德鲁·休伯曼： 和 in terms of learning multiple languages 期间 development, my understanding is 那 if 一 wants to become bilingual 或 trilingual, best to learn 那些 languages simultaneously 期间 development, ideally 之前 age 12, if 一 hopes to not have an accent in speaking them later. Is 那 correct, 或 do 你 want to revise 那 now?

Dr. Eddie Chang: Well, basically, the earlier 和-- The earlier is better. The 更多 intense it is 和 the 更多 immersive it is. The longer 那 你 可以 be exposed to 那 is 确实 重要. A lot of 人们 可以 get exposed to it early 和 basically lose it. Even though it's quote unquote 期间 那 sensitive period, unless it's maintained, it 可以 be 非常 easily lost. Then I think another aspect of it 那's 非常 interesting is some of the social Requirements 对于 it too. It's pretty clear 那 你 可以 only go so far, just listening to 这些 sounds 从 a tape recording 或 something like 那. There's something extra 关于 real human interactions 那 activates the 大脑's sensitivity to 不同的 speech sounds, allows us to become specialized 对于 them, 对于 a given language.

安德鲁·休伯曼： So returning to what's mapped, what the representations are in the 大脑. I'm starting to get a picture now based on 这些 plosives 和 这些 "th" sounds. 和 what I find so interesting 和 logical 关于 那 is it maps to the motor structures 和 the actual pronunciation of the sounds, not necessarily to the meaning of the individual words. Now, of course, it's related to the meaning of the individual words, 但 it makes good sense to me why something as complex as language, both to understand 和 to generate, 会 map to something 那 is 本质上 motor in design 因为, as 你 point out, I have to generate 这些 sounds, 和 I have to hear them generated 从 others. 然而, there's reading 和 there's writing, 和 writing is certainly motor. Reading involves some motor commands of the eyes, et cetera. Where do reading 和 writing come 进入 这 picture? Are they in parallel 与, as 我们 会 say in neuroscience, 或 are they embedded within the same structures? Are they part of the same series of computations?

Dr. Eddie Chang: Yeah. So, to address the 首先 part is 那 我们've got 这 map of 这些 不同的 parts of consonants 和 vowels, 和 when 我们 look at how they lay out in 这 part of the 大脑 那 我们 call Wernicke's area, 我们've spent a lot of time 确实 just dissecting 这 millimeter by millimeter. The term 那 你 used is 非常 apropos. It's salt 和 pepper. It's not random. There is 这 kind of selectivity to 这些 individual speech sounds, 和 一 point I want to make 关于 it is 这, is 那 in English, 对于 example, there are 关于 40 不同的 phonemes. Phonemes are just consonants 或 vowels 或 individual speech segments. 但 这些 articulatory features 那 你 refer to, 对于 example, the characteristic sounds 那 are generated by 具体的 movements in the mouth. 你 可以 更多 或 更少 减少 那 to 关于 12 不同的 features, okay? 这些 are 具体的 movements of the tongue, the jaw, the lips, the larynx. There are 关于 12 of 这些 movements. 和 just like 你 said, Andrew, by themselves, they have no meaning. They're just movements. 但 what's incredible 关于 it is 那 你 take 这些 12 movements 和 你 put them in combinations 和 你 start putting them in sequence. 我们, as humans, use 那些 12 set of features to generate all words. 和 因为 我们 可以 generate nearly an infinite number of words 与 那 code of just 12 features, 我们 have something 那 generates 本质上 all 可能 meaning. 因为 那's what 我们 do as humans, 我们 generate meanings. I'm trying to communicate 一 idea to another, which to me is extraordinary. A parallel 会 be, 对于 example, DNA. There's four base pairs in DNA, 但 与 那些 four base pairs in a 具体的 sequence 可以 generate an entire code 对于 life. 和 speech is the same way. It's like 你've got 这些 fundamental elements 那 by themselves have no meaning, 但 when 你 put them together, give rise to every 可能 meaning. So 与 regard to 你的 秒 point 关于 reading 和 writing, it's a fascinating question. Speech 和 language is part of who 我们 are as humans. 那's part of how 我们 evolved, 和 it's hardwired 和 molded by experience. Reading 和 writing are a human invention. It's something 那 was added on to the architecture of the 大脑. 和 因为 reading 和 writing are fairly recent in human evolution, it's 本质上 too quick 对于 anything to have a dramatic change in, let's say, a new 大脑 area 或 some kind of specialization. Instead, what happens is 那 whenever any kind of behavior becomes ultra-specialized, in any of us 或 any organism, 我们 可以 sort of take some areas 那 are normally involved 与 vision, 对于 example, 和 specialize it 对于 the purpose of reading. So all of us have a part of 我们的 大脑 in the back of the temporal lobe 那 interfaces 与 occipital visual cortex 那 我们 call a visual word form area. There's actually a part of the 大脑 那 is 非常 sensitive to seeing words, either typed 或 handwritten. There's a part of the 大脑 那 also is sensitive to seeing things like faces. So 这些 are things 那 are all conditioned on what's 重要 to survive. So reading 和 writing are an invention, 和 there are things 那 have mapped to functions 那 the 大脑 already has. 和 一 of the 确实 重要 things 关于 reading 和 writing is 那 when 我们 learn to read 和 write, 尤其是 与 the reading part, it maps to the part of the 大脑 那 我们've been talking 关于, which is the part 那's processing speech sounds. So some of us kind of think 关于 it, 这些 are 二 不同的 things. 一 is hearing sounds 通过 你的 ears, the other is reading, where 你're actually seeing things 通过 你的 eyes 和 then getting 进入 the language 系统. Well, it turns out 那 the auditory speech cortex is the primal 和 primitive fundamental area 那's 确实 重要 对于 speech. 和 what happens 与 the reading is once it gets 通过 那 visual cortex, it's going to try to map 那些 reading signals to the part of the 大脑 那's trying to make sense of sounds, the sounds of words, what 我们 call phonology. Now, why is 这 重要? It has a lot of relevance to how 我们 learn to write. 和 in some kids 与 dyslexia, dyslexia is a neurological condition where a child, in some cases an adult, has trouble reading, 对于 example. 和 in many of 那些 cases, it's 因为 那 mapping between how 我们 see the words to the way 那 the 大脑 processes the sounds is something 不同的. It's a little bit 不同的 than 人们 who 可以 read 确实 well. So when 你're reading, a lot of times, 你're actually activating the part of the 大脑 那 is processing the words 那 你 hear.

安德鲁·休伯曼： What is the current treatment 对于 dyslexia? I've heard 那 it's a deficit in some of the motion processing 系统 of the visual 系统. 人们, their eyes are jumping as opposed to 更多 linear reading across, 或 I suppose if it were Chinese, it 会 be I don't want to presume 人们 are 总是 reading English, 或 I suppose if it's Hebrew, they're going 从 the opposite side of the page. What 可以 be done 对于 dyslexia, 和 do any of the modern treatments 对于 dyslexia involve changing things 从 the speech side as opposed to just the, quote-unquote, reading side, given 那 speech 和 reading are interconnected?

Dr. Eddie Chang: Yeah, absolutely. So again, I think in the beginning, 人们 可能 have thought 这 was purely a visual abstraction 或 something 确实 just 关于 the visual 系统, 但 there's been 更多 recognition 那 it could be both, 或 it could be either, depending on the particular instance. It's 非常 clear 那 there are many kids 与 dyslexia where the problem is a problem of phonological awareness. So it 可以 be 非常 hard to detect 因为 they may understand the words 那 你 were saying, 但 因为 the 大脑 is so good at pattern recognition, sometimes even if the individual speech sounds are not crystal clear, it 可以 compensate 那 so 那 你 可以 have an individual who 可以 hear the words 但 not be able to 本质上 hear them when they're reading 那些 same words. 和 so what 可以 happen 与 那 is 那 你 可以 have 这 disconnection between what they're seeing 和 what they need in order to hear it as words 和 process it as language. 和 so skilled readers usually need 那 route 首先. They've got to map the vision to the sound in order to get 那 sort of foundation. 但 then over time, the reading has its direct connection to the language parts of the 大脑, 和 我们 don't necessarily 总是 need to map to sounds. 你 可以 basically develop a parallel route. 和 我们, as readers, actually use both all the time. So, 对于 example, if it's a new word 那 你've 从不 seen 之前, sometimes 你 try to pronounce it in 你的 心智 和 try to hear what 那 word is. Even though 你're not actually saying it, 你're trying to just generate what 那些 sounds 可能 be like. 和 那's the part where 我们're kind of relying on how 我们 learn to read in the 首先 place, which is mapping 那些 word images to the sounds 那 go along 与 them. 但 in other times, if 你're a 确实 proficient reader, 你're just seeing the words, 和 你 可以 map them directly to meaning 没有 having to go 通过 那 process.

安德鲁·休伯曼： Yeah, I'm a big fan of listening to audiobooks, 和 of course, I also listen to podcasts quite a lot. 但 I also am a strong believer, based on the 研究 那 I've seen, 那 reading books, physical books, could be on Kindle, I suppose, 但 reading a physical book is useful 对于 being able to articulate well 和 structure sentences 和 build what are 本质上 paragraphs, which is what I'm required to do when I do solo episodes of the podcast. I've noticed over the years as text messaging has become 更多 popular, 和 there's 本质上 an erosion of punctuation 或 the need to have complete sentences, 和 now 那's sort of transferred to email as well. It's become acceptable to just say fragmented sentences in email, 和 it seems 可能 那 it's starting to impact the way 那 人们 speak as well. 和 I don't think 这 has anything to do 与 intelligence 或 education 水平, 但 are 你 aware of any 证据 那 how 我们 read 和 what 我们 read 和 whether 或 not 我们 consume information purely 通过 reading 或 mainly 通过 auditory sources, does it change the way 那 我们 speak? 因为 之后 all, Wernicke's 和 Broca's area 和 the other auditory 和 speech production areas are heavily intermeshed, 和 so it 会 make perfect sense to me 那 what 我们 hear 和 the patterns of sound 那 are being communicated to us 会 also change the way 那 我们 speak.

Dr. Eddie Chang: Yeah. 那's a 确实 fascinating point. There's 这 idea 那 there's 这 proper way to speak, 那 there's the right way, 对于 example. What are the appropriate-- 对于 example, in school, 你're oftentimes told, "你 应该 say it like 这, not say it like 那." 和 every language kind of has 那. It turns out 那 那's 确实 unnatural. Languages, 和 speech in particular, change over time. It evolves 和 it 可以 happen 非常 quickly. The things 那 我们 call dialects, 对于 example, are just 不同的 ways of speaking, 和 someone 可以 just be in 一 environment 和 change 从 一 dialect to another. 或 in some 人们, it kind of is 确实 fixed. 和 there's 这 idea 那 in school 那 我们're told 那 there's 这 right way, 但 in reality, 那's not true. Language change 和 speech change is completely normal 和 happens all the time, 和 it 可以 be 确实 dramatic. Certain cultures 和 communities, if they are isolated, they 可以 develop a whole new language, a whole new set of words, 对于 example, 和 new ways 和 dialects 那 are independent 从 人们 to the point where it's unintelligible even to others. 和 so, the basic idea is 那 sound change is part of the way it works, 和 the 大脑 is 非常 sensitive to 那些 kind of changes.

安德鲁·休伯曼： Speaking of learning new languages, I'm assuming it's 可能 to learn new languages throughout the lifespan, correct?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： I've also heard 这些 kind of fantastical stories of somebody has a stroke 和 then suddenly, spontaneously 可以 speak French fluently, whereas prior to the stroke, they could not. Is there any merit to 那些 stories whatsoever?

Dr. Eddie Chang: No.

安德鲁·休伯曼： I find it 非常 hard to believe 那 there was a complete map representation of a language in somebody's 大脑 那 they were completely unaware of, 和 then 因为 of damage to a 大脑 area, 那 capacity to speak 那 language was somehow unveiled.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： It just seems too wild, 和 I don't want to say good to be true 因为 nobody wants a stroke, 但 it just seems outrageously implausible.

Dr. Eddie Chang: Well, there are aspects of 那 那 certainly are implausible. So I don't know of any true case 那 I've ever seen 或 experienced myself 或 even read 关于 where, 对于 example, there was an injury to the 大脑 那 resulted in loss of, well, 本质上 a gain of function, meaning just all of a sudden start speaking another language. So, 对于 example, if 你 had a stroke 和 你 从不 spoke French, 和 then 你 had it, 和 then all of a sudden 你're speaking. 那 I've 从不 heard of, 从不 seen. 然而, there is a condition 那 is well acknowledged, 和 I have seen 一 case of 这 called a foreign accent syndrome. It's peculiar 因为 there are 人们 who have an injury to the part of the 大脑 where it sounds like they're starting to speak 这 other language. 但 they're not actually speaking the language. It just sounds like it. 和 这 goes back to what 我们 were talking 关于 earlier, 关于 这些 areas 那 are 确实 重要 对于 speech control of the vocal tract, 这 area in the precentral gyrus. 人们 have documented where patients have had strokes there, 和 之后 那, it sounds like they're speaking Spanish as opposed to English, 或 it sounds like they have the intonational properties of French 或 Russian as compared to their original native language. They're not learning all the rest of it, like the meaning 和 the grammar, et cetera, 但 they're adopting some of the phonology, 和 part of 那 is just 因为 it's not working the way it normally does. So there is something actually called a foreign accent syndrome 那 人们 可以 have 之后 a stroke.

安德鲁·休伯曼： Interesting. I'm curious 关于 auditory memory. When I was a kid, I used to get 进入 bed at 夜间, 和 I'd close my eyes, 和 I 会 replay conversations 那 I had heard 期间 the 天 或 人们's voices. I actually 可以 remember calling 你的 house when 我们 were young kids, 和 因为 I don't speak any Chinese, 但 I'd have to ask 对于 你. I'd say, I think it was Eddie .

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Yeah.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： 和 then someone, whoever answered the phone 会 go get 你, 和 then I'd say which I believe means thank 你, right? 那's the total of the Chinese 那 I speak, by the way. 但 I 会 从不 forget 那. I'll just 从不 forget it. I hope. I suppose if I have a stroke 或 something of 那 sort, at some point I'll forget it, 和 I won't know 那 I've forgotten it. 但 in all seriousness, I remember 那 to 这 天. I couldn't spell 那 out. I wouldn't know how. Certainly not in Chinese, 但 even a transliteration I couldn't do using English letters. Where are memories of sounds stored? 因为 within 我们的 天 和 across 我们的 lives, 我们 have an infinite number of auditory experiences, just like 我们 have an infinite number of visual experiences. Where are they stored, 和 what is the structure of their storage? What am I calling upon, besides, of course, the motor commands 那 are required to say what I just said in Chinese, which I won't repeat again 因为 I somehow managed to get it right the 首先 time, 或 at least not terribly wrong, then I don't want to botch it the 秒 time. Where is 那 stored, 和 how does 那 work? 和 更多 importantly, as I speak my native language, English, am I pulling 从 a memory bank? 因为 it doesn't feel like it. I'm just telling 你 what I want to say. I'm doing my best to communicate clearly 和 succinctly. Usually not so good at the succinct part. 但 where is the bank of information? On my keyboard, on my computer, I have the letters, 和 I have certain elements of punctuation in the space.

Dr. Eddie Chang: Mm-hmm.

安德鲁·休伯曼： What am I pulling 从? Am I pulling 从 那些 plosives? 但 if so, how 可以 I do it so quickly? Even 对于 人们 那 speak slowly, it appears 更多 或 更少 fluid. 这, to me, is overwhelmingly impressive 那 the 大脑 可以 do 那. How does it do 那?

Dr. Eddie Chang: Well, 首先 of all, I am impressed 那 35 years later

安德鲁·休伯曼： Well, I had to get a hold of 你.

Dr. Eddie Chang: Yeah. So I am impressed 35 years later 那 你 可以 still remember 那.

安德鲁·休伯曼： 但 only 那.

Dr. Eddie Chang: 那's fine. 但 I'm still 非常 impressed. 但 it clearly was something 重要 to 你. 和 so the short answer is 那 memory is 非常 distributed. So it's almost like the question 那 你 asked me is ill-posed 因为 你 asked me where. Well, it's not 一 具体的 area. It's actually 确实 distributed. It's not just 一 particular area. In fact, I'm fairly certain 那 if 我们 were to injure 那 part of the 大脑 called the Wernicke's area, 你 may still even have memories of 那. 人们 可以 have injuries of Broca's area 或 certainly the precentral gyrus 和 be able to sing "Happy Birthday," 对于 example, when it's embedded in melody 或 highly rehearsed things like counting, despite not being able to speak, which is incredible, right? It's like 你 可以 see a patient, 对于 example, who 可以't 确实 put together a sentence. 你 ask them, "How are 你 feeling today?" They 可以't even utter a word, 但 then 你 ask them to count sometimes, 和 they'll get up to any number, 确实. 和 so there are some things 那 are 确实 built 进入 我们的 motor memory, 和 it's distributed. It's not 一 particular part of the 大脑. It's actually multiple areas where 那 memory is distributed. 和 thank God 那's the way it is, 因为 it's 非常 rare in the kind of surgeries 那 I do, where 你 go 和 你 remove a piece of the 大脑, 那 someone forgets 这些 kind of long-term memories 或 这些 long-term motor skills 那 they have. 那's 非常, 非常 rare. It's the number 一 question a patient 会 ask me, like, "Am I going to be the same? Am I going to remember my wife," 或, "Am I going to remember 这些 thoughts of my birthday when I was 10 years old?" 和 I've 从不 确实 seen 那 kind of severe amnesia, unless it's a 非常, 非常 severe injury 那 involves almost the entire 大脑. 和 thank God. So a lot of 那 information is 确实 distributed across the entire 大脑.

安德鲁·休伯曼： Speaking of storage of 和 ability to speak, 你 are doing some amazing work 和 have achieved some pretty incredible, well-deserved recognition 对于 你的 work in bringing language out of paralyzed 人们. 本质上 allowing 人们 who are locked 进入 a paralyzed state 或 otherwise unable to articulate speech using 大脑 machine interface, 本质上 translating the neural activity of areas of the 大脑 那 会 produce speech 进入 hardware, wires, 和 things of 那 sort, artificial, non-biological tools in order to allow paralyzed 人们 to communicate. 我们 会 provide a link to some of the popular press coverage of 那 work in the original papers. 但 if 你 会 be so kind as to tell us what 那些 experiments look like, who 这些 人们 are who are locked in 和 那 你 allow to communicate. 和 then 尤其是 interesting to me are some of the directions 那 你're taking 这 now, which is beyond just 人们 being able to think 关于 what they want to say 和 words coming out on a screen 或 通过 a microphone, 但 actually making the interactions between 这些 人们 in the real world 更多 elaborate 和 更多 real. If 那 seems mysterious to 人们, I'm going to let Eddie tell 你 what they're doing 与 这 rather than put any 更多 detail on it.

Dr. Eddie Chang: Oh, okay. Well, thanks 对于 asking 关于 这. 这 has 确实 been some of the exciting recent work 从 the lab. So 对于 the last decade, 我们've 确实 been focusing on the basic science, meaning trying to understand how the 大脑 extracts 和 produces speech sounds 和 words. 我们've done a lot of work trying to figure out how 这些 parts of the 大脑 control 这些 individual elements 那 give rise to all words 和 meanings. 和 so it was 关于 six years ago where 我们 realized 我们 actually have a pretty good idea of how 这 code works. 我们 had identified all of 这些 不同的 elements 那 我们 could decode in epilepsy patients, 对于 example, when they had electrodes on the 大脑 as part of their surgeries. 我们 could decode all of the 不同的 consonants 和 vowels of English. 那 was 关于 six years ago. So a natural question was 这, which is, if 我们 understand 那 electrical code, 可以 我们 use 那 to help someone who is paralyzed 和 可以't get 那些 signals out of the 大脑 to speak normally? 和 那's in the setting of 人们 who are paralyzed. So there are a series of conditions. They include things like brainstem stroke. The brainstem is the part of the 大脑 那 connects the cerebrum, which is the top part, does 我们的 thinking 和 a lot of the motor control, speech, language, everything. 和 the brainstem is what connects 那 to the spinal cord 和 the nerves 那 go out to the face 和 vocal tract. So if 你 have a stroke there, basically, 你 could be thinking all the wild, creative, intelligent thoughts 你 have in the 心智, in the cerebrum, 但 你 可以't get them out 进入 words, 或 你 可以't get them out to 你的 hand to write them down. So 那's a 非常 severe form of paralysis called brainstem stroke. There's another kind of conditions 那 我们 call neurodegenerative, where the nerve cells die, basically, 或 atrophy in a condition called ALS. 和 那's a 非常 severe form of paralysis. In its extreme form, 人们 本质上 lose all voluntary movement.

安德鲁·休伯曼： So Stephen Hawking 会 be a good example of someone 与 ALS, Lou Gehrig's disease?

Dr. Eddie Chang: He's an example of someone who had ALS, 但 not a great example of what typical course of ALS. So 对于 reasons not clear, the progression of his disease largely stabilized to the point where he could twitch, as a cheek 肌肉 或 move his eyes, let's say. In most 人们, it's 非常 rapid, 和 many 人们, they die 从 it, actually, within a couple of years of diagnosis. So-

安德鲁·休伯曼： Yeah, he lived a long time in 那.

Dr. Eddie Chang: He lived a long time. 和-

安德鲁·休伯曼： 那 slanted over state in his wheelchair

Dr. Eddie Chang: Right. Exactly.

安德鲁·休伯曼： Yeah.

Dr. Eddie Chang: 但 he wasn't breathing 通过 a tube in his throat, 对于 example, 因为 人们 与 severe ALS, the 肌肉 to their diaphragm 和 their lungs 本质上 give out as well. They get weakness there, 和 then they 可以't breathe anymore. So 那's another form of paralysis. 和 so in 我们的 field, 这些 are kind of like the most devastating things 那 可以 happen. I'm not going to 确实 try to compare, like, what's worse, having a 大脑 tumor 或 a stroke. It's all bad. 但 这 condition of what 我们 call being locked in refers to 这 idea 那 你 可以 have completely intact cognition 和 awareness, 但 have no way to express 那, no voluntary movement, no ability to speak. 和 那 is devastating 因为, psychologically 和 socially, 你're completely isolated. 那's what 我们 call locked-in syndrome. 和 it's devastating. I've seen 那 throughout my career, 和 it's 确实 heartbreaking 因为 你 know 那 the person is there, 但 你 可以't see, 和 they 可以't communicate. So 我们've been studying 这 patterning of electrical activity 对于 consonants 和 vowels. 和 本质上, once 我们 figured out a lot of 这些 codes 对于 the individual phonetic elements, 我们 took a little bit of a detour, 或 at least part of the lab started to 专注 on 这 非常 具体的 question. 对于 人们 who have 这些 kind of paralysis, could 我们 intercept 那些 signals 从 the 大脑, the cerebral cortex, as someone is trying to say 那些 words, 和 then 可以 我们 intercept them 和 then have them taken out of the 大脑 通过 wires to a computer 那 are going to interpret 那些 signals 和 translate them 进入 words? So 关于 三 years ago, 我们 started a clinical trial. It's called the BRAVO trial. It's still underway. 和 the 首先 participant in the BRAVO trial was a man who had been paralyzed 对于 15 years. When he was 关于 20 years old, he came to the United States, was actually working in Sonoma area, 和 he was in a car accident, 和 he actually walked out of the hospital the 天 之后 那 car accident. 但 the next 天, had a complication related to it where he had a 非常 large stroke in the 大脑 stem, 和 那 turned out to be devastating. He didn't wake up 从 那 stroke 对于 关于 a 周. He was in a coma 对于 关于 a 周, 和 when he woke up 从 那 coma, he realized 那 he couldn't speak 或 move his arms 或 legs. 和 as he told me 或 communicated to us, 那 was absolutely devastating. He wanted 确实 to die at 那 time.

安德鲁·休伯曼： Could he blink his eyes 或 move his mouth in any way?

Dr. Eddie Chang: He could blink his eyes. He had some limited mouth movements, 但 couldn't produce any intelligible speech. It was completely slurred 和 incomprehensible. 和 he survived 这 injury. A lot of 人们 who have 那 kind of stroke just don't survive. 但 he survived, 和 I also realized 那 he's just an incredible person, like a force of nature in terms of his optimism, in terms of his ability to make friends despite his condition. The way he actually communicates, 因为 he has a little bit of residual neck movements, is 那 he improvised 和 had his friends basically put a stick attached to his baseball cap. 和 因为 he could move his neck, he 会 本质上 type out letters on a keyboard screen to get out words. In fact, 这 is how he communicated, was 通过 a device 那 he 会 本质上 peck out letters 一 by 一 by moving his neck to control 这 stick attached to his baseball cap.

安德鲁·休伯曼： How many years did he use 那 method of communication until-

Dr. Eddie Chang: 对于 关于 15 years. He hadn't 确实 spoken 对于 关于 15 years.

安德鲁·休伯曼： Oh, goodness.

Dr. Eddie Chang: Yeah. So, it was a devastating injury, 但 there's something to be said 关于 the human spirit, 和 if there's anyone who embodies it, it is Pancho, 那's his nickname, the 首先 participant in 我们的 trial. He has 那 human spirit. He persevered, 和 in fact could thrive in his community, basically, 和 friends, be able to communicate in 这 非常 slow 和 inefficient way. Maybe part of 那 spirit is why he volunteered to be the 首先 person in 这 trial. It was a clinical trial, an experiment. It was a 研究. 这 is not an approved therapy by any means. 这 was 确实 something 那 had not been done 之前 和 我们 had a lot of ideas 关于 it, 但 我们 didn't know. 我们 had proven a lot of 这 could be true in some 人们 who are normally speaking. 但 to actually put 进入 someone who's paralyzed, number 一, where 我们 don't know the code is the same, 和 number 二 is someone who's not been speaking 对于 15 years, whether 那些 signals are actually still there 或 not. So it was part of a clinical trial. It was something 那 我们的 hospital 和 also the FDA had to approve 和 looked at 非常 carefully. 但 given a lot of the work 那 我们 had done, there was some basis 对于 why 这 可能 work. 和 so 关于 二 和 a half years ago, 我们 did a surgery where 我们 implanted electrodes onto the parts of the 大脑 那 我们've been talking 关于, 这些 areas 那 control the vocal tract, the areas 那 control the larynx, the areas 那 control the lips 和 tongue 和 jaw movements when 我们 normally speak. 这些 are areas 那 presumably may be active, 那 was 我们的 hope, in his 大脑, 但 he just couldn't get 那些 out to control his mouth in a normal way. 和 he underwent a surgery, a 大脑 surgery. 我们 put an electrode array 和 我们 connected it to a port 那 was screwed to his skull. 和 the port actually goes 通过 his scalp, 和 he's lived 与 这 now 对于 the last 三 years. It is a risk of infection. 这些 ports eventually have to become wireless in the future. 但 我们 figured out a way to keep 那 port there, where 我们 可以 本质上 connect him to a computer 通过 那 port. So he has an electrode array 那's implanted over the part of his 大脑 那's 重要 对于 speech. It's connected to a port. 和 then 我们 connect a wire to 那 port 那 translates 那些, what 我们 call analog brainwaves, 和 converts them 进入 digital signals. 和 then a computer takes 那些 digital signals 从 那些 individual sites 从 the speech cortex 和 translates 那些 进入 words.

安德鲁·休伯曼： 可以 你 describe 对于 us the 首先 time 那 Pancho spoke 通过 这 engineered device? What was 那 experience like 对于 你? 和 at least 从 what he conveyed to 你, what was 那 experience like 对于 him? 这 is somebody who was 本质上 locked in except 对于 这 rather crude pecking device. 尽管 I'm thoroughly impressed by how adaptive 或 adaptable Pancho was 和 his friends engineering 那 device 对于 him is 确实 nothing short of clever. 和, 因为 otherwise he 会 be truly locked in.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Right. 但 what was 那 moment like? I 可以 only imagine.

Dr. Eddie Chang: 那 moment was incredible. It was truly incredible, to be able to see him try to get out a word 那 was, 对于 all practical purposes, unintelligible, 但 to be able to take the 大脑 activity 和 to translate it 进入 text on a screen. 和 那's what 我们 did. 我们 took 那些 brainwaves, 我们 put them 通过 machine learning 或 artificial intelligence algorithm 那 可以 pick up 这些 非常, 非常 subtle patterns, 你 可以't actually see them 与 你的 eye in the 大脑 activity, 和 translate 那些 进入 words. 和 I remember seeing 这 happening 对于 the 首先 time. It doesn't happen immediately. 这 is something 那 took 周 to train the algorithm to interpret it correctly. 但 what was incredible 关于 it was to see how he reacted. 和 he 会 be prompted to say a given word, like "outside," 对于 example, 和 then he 会 think 关于 it, try to say it, 和 finally 那些 words 会 appear on the screen. 和 what was 确实 amazing 关于 it was 你 could 确实 tell 那 he got a kick out of it 因为 he 会 start to giggle. His 身体 会 shake in a way, 和 his head 会 shake in a way 那 he 会 start to giggle, 和 那 was cool to see. 但 then I also realized 那 when he was giggling, it kind of screwed up the next words' decoding.

安德鲁·休伯曼： Is 那 a bug 你've since fixed?

Dr. Eddie Chang: No, 我们 haven't fixed 那.

安德鲁·休伯曼： Interesting.

Dr. Eddie Chang: 我们 haven't fixed 那, so it's easier just to tell him to stop giggling.

安德鲁·休伯曼： So what was the 首先 word 那 he said?

Dr. Eddie Chang: Well, I think 一 of the 首先 sentences 那 he put together was, "可以 你 get my family outside?" 和-

安德鲁·休伯曼： Meaning get them out of the room?

Dr. Eddie Chang: No, no.

安德鲁·休伯曼： All 这些 years, he wanted to get away 从 his family?

Dr. Eddie Chang: No, I think what he meant was 可以 你 get them-

安德鲁·休伯曼： Bring them in

Dr. Eddie Chang: ... bring them in.

安德鲁·休伯曼： Yeah.

Dr. Eddie Chang: 和 so the way 这 worked was 我们 trained 这 computer to recognize 50 words. 我们 started 与 a 非常 small vocabulary, 那's expanding as 我们 speak. I think 那 这 is just a matter of time 之前 这些 vocabularies become much, much larger. 但 我们 started 与 a 50 set of words. 我们 created 本质上 all the 可能 sentences 那 你 could generate 从 那些 50 words. Why 那 was 重要 was 你 可以 use all 那些 可能 sentences to create a computational model, a computer model, of all the 不同的 word combinations to give 不同的 sentences, given 那些 50 words, 和 then 你 可以 本质上 do what 我们 call autocorrect. It's the same kind of thing 那 我们 do when 你're texting, 对于 example, 你 get the wrong letter in there, 但 你的 phone actually knows, 因为 of its context, what to correct it. So 因为 the decoding is not 100% correct all the time, in fact, it's far 从 那, it's 确实 helpful to have 这些 other features like autocorrect, the stuff 那 我们 use routinely now 与 texting 那 makes it correct 和 then updates it. So it's a combination of a lot of things. It's the AI 那 is translating 那些 大脑 activity patterns, 但 it's also things 那 我们've learned 从 speech 和 speech technologies 那 你 put all together 和 then all of a sudden it starts to work. 和 so, 我们 were 确实 excited 因为 那 was the 首先 time 那 someone was paralyzed 和 could create words 和 sentences 那 was just decoded 从 the 大脑 activity.

安德鲁·休伯曼： Incredible. 和 I know 你're 非常 humble, 但 I'm going to embarrass 你 by saying I 总是 knew 你 were destined 对于 great things since the early age of nine when 我们 首先 became friends. 但 when I read the news coverage of 你的 work 与 Pancho 和 the 释放 of 这 language 从 这 locked-in patient, it literally brought tears to my eyes 因为 it's an interesting thing as fellow neuroscientists, 我们 explore the 大脑, 和 我们 try 和 find mechanisms, 和 我们 try 和 compare 那些 to what other 人们 find, 和 find truths 和 principles 和 build up 从 那些. 但 pretty rarely is there a case where 那 route of exploration leads to something of clinical significance within 一's own lifetime. 那's the reality of science, 和 oftentimes it's a 非常 distributed process. 但 in 这 case, it's been a magnificent thing to see 你 move along 这 trajectory, parsing 这些 language 和 speech areas, 和 then to also do the clinical work in parallel. Speaking of which, 这些 天, 我们 hear a lot 关于 Neuralink, Elon Musk's company. A neurosurgeon 那 came up briefly 通过 my lab, 但 I 可以't take any credit 对于 what he knows 或 does, which is Matt MacDougall is the neurosurgeon at Neuralink. There's some other excellent neuroscientists there 和 engineers there. 我们 hear a lot 关于 Neuralink 因为 while 大脑 machine interface of the sort 那 你 do 和 那 other laboratories do has been going on 对于 a long time, there's been some press 大约 Neuralink 关于 the promise of what 大脑 machine interface could do. 对于 instance, early in 我们的 discussion, 你 talked 关于 how language is constrained by 这些 sound waves, 和 通常, it's a few 人们 communicating, 或 一 person 与 many 人们 通过 a podcast, 对于 instance, 或 a speech. 但 the idea has been thrown out there 那 通过 the use of stimulating chips 或 通过 other 大脑 machine devicing, 那 perhaps 一 could internalize 50 conversations in parallel. 50x communication. 或 那 the memory 系统 could be augmented to remember 10 times as much information 或 even twice as much information in a given period of time. My understanding of what they're doing at Neuralink, which is admittedly crude 和 从 the outside, a few discussions 与 人们 there, is 那 they, too, are going to pursue clinical goals 首先. Things like trying to generate smooth movement in a Parkinsonian patient, trying to adjust movement patterns in someone 与 Huntington's disease, 对于 instance, things of 那 sort, 之前 they embark on the 更多 sci-fi-like explorations of 50xing communication 或 doubling memory capacity 和 这些 kinds of things. 尽管, I don't know, they may be doing all of 那些 things in parallel. What are 你的 thoughts 关于 super capabilities of the 大脑, 或 I don't even know what word to use, supercharging the 大脑, giving the 大脑 functions 对于 which 我们've 从不 observed 之前 in human history. 我们 have 我们的 Einsteins 和 我们的 Feynmans 和 我们的 Merzenichs 和 it's unclear who to put in along 那 line side by side. There are Michael Jordans, et cetera, 但 我们've 从不 heard of 或 seen somebody who 可以 jump 20 feet in the 空气, 或 我们've heard of 人们 who have photographic memories, 但 I don't know 那 我们 are aware of any human being in history who could memorize the entire Library of Congress 或 all the works within the Vatican within an 小时. Anyway, 你 get the idea. What are 你的 thoughts 关于 manipulating neural circuitry to achieve superhuman 或 super physiological functions? Are 我们 there 或 应该 我们 even be thinking 关于 那? Is it 可能 given 那 neurons simply communicate 通过 electrical activity 和 electrical activity 可以 be engineered outside of the 大脑? How do 你 think 关于 it? 和 here 我们 don't even have to think 关于 Neuralink in particular. It's just 但 一 example of companies 和 人们 in laboratories 那 are quite understandably considering all 这.

Dr. Eddie Chang: Well, it's a 确实 interesting time right now. The science has been going on 对于 decades. The work 那 我们've done in 这 field 那 你 call 大脑 machine interface, it's been going on 对于 a while, 和 a lot of the early work was just trying to restore things like arm movement 或 having 人们 或 monkeys control a computer cursor, 对于 example, on the screen. 那's been going on 对于 decades. What's been 确实 new is 那 industry is now involved, 和 some of 这 is now becoming commercialized, 和 我们're starting to see us now cross over to 这 field where it's no longer just 研究, 那 我们're talking 关于 medical products 那 are designed to be surgically implanted. In some cases, there's 人们 doing 这 kind of work non-invasively as well, 那 don't require surgery. The 具体的 question 那 你 are asking 关于 is an area 那 我们 call augmentation. So 可以 你 build a device 那 本质上 增强 someone's ability beyond supernormal, super memory, super communication speeds beyond speech, 对于 example? I guess superior precision athletic abilities. I think 那 这些 are 非常 serious kind of questions to be asking now 因为, as 你 mentioned, the 通路 so far is 确实 to 专注 on 这些 medical applications. I personally don't think 那 我们've thought enough, actually, 关于 what 这些 kind of scenarios are going to look like, 和 I don't think 我们've thought 通过 all the ethical implications of what 这 means 对于 augmentation in particular. There's part of 这 那 is not new at all. Humans throughout history have been doing things to augment 我们的 function. Coffee, nicotine, all kinds of things, all kinds of medications 那 cross over 从 medical to consumer. 那 is everywhere. So the pursuit of augmentation 或 表现 或 enhancement is 确实 not a new thing. The questions 确实, as they relate to neurotechnologies, 对于 example, have to do 与 the invasive nature. 对于 example, if 这些 technologies require surgery, 对于 example, to do something 那 is not 对于 a medical application. Again, there, 那 is not exactly new territory either. 人们 do 那 routinely 对于 cosmetic kind of procedures, 对于 physical appearance, not necessarily cognitive. So I do think 那 provided the technology continues to emerge the way 那 it does, 那 it's going to be 大约 the corner, 和 it probably is not going to be in ways 那 are super obvious. I don't think it's going to be like, 可以 我们 easily memorize every fact in the world? 但 in forms 那 are going to be much 更多 incremental 和 maybe 更多 subtle. In many ways, 我们 already have 那 now. Like, 对于 example, 你 don't have to have a neural interface embedded in 你的 大脑 to get 本质上 access to all information in the world. 你 just have to have 你的 iPhone. Whether 你 could do it faster 通过 a 大脑 interface, I definitely wouldn't rule 那 out. 但 think 关于 这, 那 the 系统 那 我们 have already to speak 和 to communicate have evolved over thousands 和 millions of years, 和 they're supported by neural structures 那 have bandwidth of millions of neurons. There's no technology 那 exists right now 那 人们 are thinking 关于 那 are in commercial form, certainly, not even in 研究 labs, 那 come anywhere close to what has been evolved 对于 那些 natural purposes. So I'm 本质上 saying 二 sides of 这, which is 我们're already getting 进入 这 now. 这 is not new territory, 这 topic of augmentation, both physical 和 cognitive. 我们've already surpassed 那. 那's part of what humans do in general. 但 我们 are entering 这 area of enhanced cognition, 这些 areas 那 I think the technology is going to be the rate-limiting step in how far 我们 可以 go, 和 我们 have not had the full conversations 关于, number 一, is 这 what 我们 actually want? Is 这 going to be good 对于 society? Who gets access to 这 technology? 这些 are all things 那 are going to become real-world problems.

安德鲁·休伯曼： There's certainly a lot to consider. In thinking 关于 augmentation 和 another theme 那 I've yet to ask 你 关于, 但 I'm extremely curious 关于, which is facial expressions. 之前 我们 talk 关于 the relationship between the musculature of the face 和 language 和 the communication of emotion, I'd love 对于 你 to, if 你 会, touch on a little bit of what 你're doing 与 patients like Pancho to move beyond somebody who's locked in being able to type out words on a screen 与 their thoughts. There's a rich array of information contained within the face 和 facial expression, 和 while somebody like Pancho going 从 having to be completely locked in to being able to peck out letters on a keyboard to being able to just think of 那些 letters 和 having them spelled out, 那's a tremendous set of leaps forward towards normalcy. It's still far 和 away 不同的 than Pancho speaking 与 his mouth, which I think, knowing some 人们 who are restricted, who are quadriplegic, a lot of what they struggle 与 in the real world is actually a height difference sometimes 因为 they're seated while other 人们 are standing. 这 actually, 我们 don't 经常 think 关于 这, 但 to 总是 have to look up to communicate 与 人们 is a 非常 不同的 interface in the world. They manage quite well, of course, 但 could 你 tell us what 你're doing in terms of merging the 大脑 machine interface 与 extraction of speech signals 从 人们 who are locked in, like Pancho, 与 facial expressions?

Dr. Eddie Chang: Sure. Yeah. Well, like 我们 described 之前, progress is being made. The proof of principle is out there 那 你 可以 decode speech. 那 会 continue to optimize, 和 I'm 非常 confident 那 那's going to 改善 非常, 非常 quickly in the coming years to the point where it's not just a small vocabulary, 但 a large vocabulary 和 at reasonable rates at a 水平 那's going to be 确实 helpful. I'm 非常 optimistic 关于 那. I think it's the right time to start 确实 thinking 关于 a broader vision of what communication 确实 is. So, 对于 example, I'm here 与 你 in person. 我们 could have done 这 virtually, probably. It's pretty easy to do 那. 我们 could have recorded 这 确实 separate, 但 there is something 关于 being able to actually see 你的 expressions 和 to understand other forms of communication. So another 确实 重要 一 is non-verbal. The expressions 那 你're making. 对于 example, if 你 have a quizzical look on 你的 face, if I'm saying something not clear, 那's a sign to me 那 I need to rephrase it 或 to say it in a 不同的 way 或 to slow down, 对于 example. 或 if there's something 那 确实 excites 你, I want to continue to say 更多 关于 it 和 talk 更多 in detail 本质上 关于 a given thing. So facial expressions actually are a 确实 重要 part of the way 我们 speak, 和 there's 二 things. It's not just the expressions of how 你're feeling 和 perceiving what I'm saying, 但 it's also Seeing my mouth move 和 你的 eyes actually seeing my mouth move 和 my jaw move in a particular way, 那 actually allows 你 to hear 那些 sounds better. So having both the visual information, 但 also the sounds go 进入 你的 大脑 is going to 改善 intelligibility, also make it 更多 natural.

安德鲁·休伯曼： 和 memory 对于 what is spoken?

Dr. Eddie Chang: Perhaps.

安德鲁·休伯曼： So here's a call 对于 人们 not just listening to podcasts, 但 watching them 和 listening to them on YouTube, I suppose, if 我们 were to translate 这 to-

Dr. Eddie Chang: Exactly

安德鲁·休伯曼： ... the real world.

Dr. Eddie Chang: Exactly. 和 the reason why 我们're also 非常 interested in 这 idea of not just having text on a screen, 但 本质上 a fully computer-animated face, like an avatar of the person's speech movements 和 their facial expressions, is going to be a 更多 complete form of expression. Now, 你 可以 imagine right now 那 可能 just be someone looking at a computer screen interpreting 这些 signals. 但 I think the way things are going in the next couple of years, a lot 更多 of 我们的 social interactions, 更多 than even now, are going to move 进入 这 digital virtual space. 和 of course, most 人们 are thinking 关于 what 那 means 对于 most consumers, 但 it also has 确实 重要 implications 对于 人们 who are disabled, right? 和 how are they going to participate in 那? 和 so 我们're thinking 确实 关于 对于 人们 like Pancho 和 other 人们 who are paralyzed, what other forms of BCI 可以 我们 do in order to help 改善 their ability to communicate? So 一 is 本质上 building out 更多 holistic avatars. Things 那 可以 本质上 decode their expressions 或 the movements associated 与 their mouth 和 jaw when they actually speak to 改善 那 communication.

安德鲁·休伯曼： So do 你 envision a time not too long 从 now where instead of tweeting out something in text, I'll type it out, 但 my avatar 会 just say it. It'll be an image of my avatar saying whatever it is I happen to be tweeting at 那 moment.

Dr. Eddie Chang: 那's what 我们're working on, yeah. So I don't think 那 那... 那 is going to happen, 和 it's going to happen soon, 和 there's a lot of progress in 那. 和 again, 我们're just trying to enrich the field of communication expression to make it 更多 normal. 和 我们 actually think 那 having 那 kind of avatar is a way of getting feedback to 人们 learning how to speak 通过 a speech neuroprosthetic. 那's the device 那 我们 call it. It's a speech neuroprosthetic. 那 那 is going to be the way 那 可以 help 人们 learn how to do it the quickest. Not necessarily trying to say words 和 having it come on a screen, 但 actually have 人们 embody, feel like it's part of themselves, 或 那 they are directly controlling 那 illustration 或 animation.

安德鲁·休伯曼： 这 idea of an avatar speaking out what 我们 会 otherwise write is fascinating to me. On Instagram, I post videos. I don't filter them, 但 I know there's a lot of discussion nowadays 关于 人们 using filters to make their 皮肤 look 不同的 或 the lighting look 不同的. A lot of filtering 和 also the use of captions, so 那 本质上 what 你 end up 与 is somewhere between an actual raw video of what was spoken 和 an avatar version of it.

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： If the mismatch between what's spoken 和 what's in the caption is too dramatic, then it doesn't quite work. 但 I watch 这些 carefully when 人们 use captions, 和 oftentimes there's a smoothing of what was said 进入 the caption, so it seems much 更多 succinct 和 accurate. Oftentimes, the reverse is also true, where the caption is inaccurate, 和 then it creates 这 kind of jarring mismatch. In any case, I think 这 aspect in the clinical realm of using an avatar to allow 人们 like Pancho to 本质上 be a face 那 communicates 通过 spoken language 从 an avatar 那 looks like them is fascinating 和 indeed 重要, 和 I think how avatars emerge in social spaces is going to be 确实 fascinating. I get a lot of questions 关于 stutter. I think 那 对于 人们 who have a stutter, it is itself anxiety-provoking. Is stutter related to anxiety? If 一 has a stutter, what 可以 they do?

Dr. Eddie Chang: Mm-hmm.

安德鲁·休伯曼： Does stutter reflect some underlying neurologic phenomenon 那 可能 distinguish between 一 kind of stutter 和 another? What 可以 人们 与 stutter do if they'd like to relieve their stutter?

Dr. Eddie Chang: Yeah. Great question. Stutter is a condition where the words 可以't come out fluently. So 你 have all the ideas, 你've got the language intact. Remember, 我们 talked 关于 这 distinction between language 和 speech. Stuttering is a problem of speech, right? So the ideas, the meanings, the grammar, it's all there, 和 人们 stutter, 但 they 可以't get the words out fluently. So 那's a speech condition, 和 in particular, it's a condition 那 affects articulation, specifically 关于 controlling the production of words in 这 确实 coordinated kind of movements 那 have to happen in the vocal tract to produce fluent speech. 和 stuttering is a condition where 人们 have a predisposition to it. So there's an aspect of stuttering, 你 are a stutterer 或 你're not a stutterer, right? 但 人们 who stutter don't stutter all the time either. So 你 could be a stutterer who stutters at some times 但 not others. 和 确实, the main link between stuttering 和 anxiety is 那 anxiety 可以 provoke it 和 make it worse. 那's certainly true, 但 it's not necessarily caused by anxiety. It 可以 本质上 trigger it 或 make it worse, 但 it's not the cause of it, per se. So the cause of it is still 确实 not clear, 但 it does have to do 与 这些 kind of 大脑 functions 那 我们've been talking 关于 earlier, which is 那 in order to produce normal fluent speech, 我们're not even conscious of what is going on in 我们的 mouths, in 我们的 larynx. 我们're not conscious, 和 if 我们 were, 我们 会 not be able to speak 因为 it's too complex, it's too precise. It's something 那 我们 have 确实 developed the abilities to do, 和 我们 do it naturally, right? It's part of 我们的 programming 和 part of what 我们 learn inherently, innate, it's just 通过 exposure. So stuttering is 本质上 a breakdown at certain times in 那 machinery being able to work in a 确实 coordinated way. 你 可以 think 关于 the operations of 这些 areas 那 are controlling the vocal tract. Let's say speech is like a symphony. In order 对于 it to come out normally, 你've got to have not just 一 part, the larynx, 但 the lips, the jaw. They 可以't be doing their own thing. They have to be 非常, 非常 precisely activated 和 非常, 非常 precisely controlled in a way to actually create words. 和 so in stuttering, there's a breakdown of 那 coordination.

安德鲁·休伯曼： If somebody has a stutter, is it better to address 那 early in life when there's still neuroplasticity 那 is 非常 robust? 和 if so, what's the typical route 对于 treatment? I have to imagine it's not 大脑 surgery, 通常. I'm guessing there are speech therapists 那 人们 可以 talk to, 和 they 可以 help them work out where they're getting stuck in the relationship to anxiety.

Dr. Eddie Chang: Yeah, exactly. Part of it is 关于 那 anxiety, 但 a lot of it 确实 has to do 与 therapy to sort of work 通过 和 think of tricks, basically, sometimes to create conditions where 你 可以 actually get the words to come out. Some forms of stuttering are 确实 initiation problems. Just getting started itself is 非常 hard. 你 want to start 与 the initial vowel 或 consonant, 但 it won't emit. 和 so a lot of the therapy is 确实 just focusing on how do 你 create the conditions 对于 那 to happen. There's another aspect to it 那 I find 非常 interesting, is 那 the feedback, 本质上, what 我们 hear ourselves say, 对于 example, 和 every time 那 I say a word, I'm also hearing what I'm saying, so 那's what 我们 call auditory feedback. 那 turns out to be 非常 重要, 和 sometimes when 你 change 那, it 可以 actually change the amount someone stutters, 对于 better 或 对于 worse. 和 it's giving us a clue 那 the 大脑 is not just focused on sending the commands out, 但 it's also possibly interacting 与 the part 那 is hearing the sounds, 和 there's something 可能 be going on in 那 connection 那 breaks down when stuttering occurs. So there are 个体 那 are stutterers, 但 they don't stutter all the time. In 那些 instances, there's something happening in 那些 particular moments where 这 非常, 非常 precise coordination needs to happen in the 大脑 in order to get the words out fluently.

安德鲁·休伯曼： 我们 talked a little bit 关于 caffeine 和 why 你 avoid it. 因为 你的 work requires such precision 和 calm, 和 frankly, to me, it seems like 你're running a lot of operations 和, no pun intended, in parallel when 你're doing surgery, not just thinking 关于 where to direct the instruments, 但 also thinking like a chess player, several steps down the line, what could happen, what if, if then type thinking. What are some of the other practices 和 tools 那 你 use to put yourself 进入 state 对于 optimal neurosurgery 或 对于 thinking 关于 scientific problems 对于 那 matter? 我们 keep threatening to go running together, 但 I know 你 run, correct?

Dr. Eddie Chang: Yeah.

安德鲁·休伯曼： Do 你 find running to be an essential part of 你的 state regulation?

Dr. Eddie Chang: Absolutely. Yeah. So 对于 me, most 运动 那 I do, I 确实 don't do 对于 physical reasons, I do it 对于 mental reasons. I 可以 tell, 对于 example, if I don't go on a run 或 a swim just 之后 a 天 或 二, 和 it 可以 have translation, 对于 example, in the way I feel in the operating room 或 even the way I interact 与 other 人们. So there's no question 那 the 心智 和 身体 are deeply connected. 和 对于 me personally, being able to have opportunity to disconnect 对于 a while, it turns out to be 确实, 确实 重要. Now, the operating room 对于 me is another space, kind of like running 或 swimming, where I'm disconnected 从 the rest of the world. I don't bring my cellphone 进入 the operating room. I'm disconnected 从 the external world 对于 那 time 那 I'm in the surgery, 和 all I am doing is just focusing. Now, 那 doesn't mean 那 I'm having complex thoughts 或 doing something 非常 complicated. Sometimes it is like 那, 但 it's not 总是 like 那. There are things 那 我们 do in surgery 那 are routine 和 rote 和 are 从 肌肉 memory. So 对于 example, suturing 皮肤 或 doing certain kinds of dissection 或 drilling part of the bone, 对于 example. 这些 are all things 那 become 非常 rote 之后 a time. So 对于 me, even being in the operating room actually 可以 sometimes fulfill 那 purpose. So I 确实 look forward to being in the operating room 因为 那 intense 专注 allows me to sort of disconnect 从 all the other things 那 I'm worrying 关于 那 are happening on the outside world. 我们 all have 那些 kind of things 那 happen, 和 I'm certainly no exception to 那. 但 strangely, the operating room 对于 me is a sanctuary. I love being there 因为 我们 have some control over the environment. I know what is there. I know the anatomy of the 大脑. My motions are going 通过 routines. 和 so 对于 me, 那's not actually 非常 不同的 than going on a run 和 letting my legs move in 具体的 ways. It's just the same thing 对于 my hands.

安德鲁·休伯曼： Do 你 listen to music 或 audiobooks when 你 run, 或 are 你 divorced 从 technology when 你 run?

Dr. Eddie Chang: Well, music helps me just stay motivated 和 distracted 从 being out of breath 和 other things. 和 对于 me, it's a way just to catch up 与 the world. So sometimes I do, 但 I do notice 那 I don't run as well, 对于 example. In the operating room, it's a little 不同的. 不同的 surgeons have preferences. I'm 更多 of the camp where I don't like any distraction whatsoever. I like 人们 to be able to hear the words 那 I'm saying 没有 having background noise. I don't 确实 think 关于 relying on music 或 other things to try to put me in a state of 心智. I think just being there alone 和 just trying to treat it the way it is, it's a sacred moment where someone's life is 确实 directly under 你的 hands. 那 enough kind of focuses me 非常 quickly, 和 I like 那. It 确实 detaches me 从 a lot of things 那 are preoccupying me. 和 对于 那些 couple of 小时 那 我们 have a surgery, 我们're just focused on 一 thing only.

安德鲁·休伯曼： It's fantastic. Again, I think of in the range of 大脑 explorers, the neurosurgeons, 那些 of 你的 profession, are to me like the astronauts of neuroscience 因为 they're 确实 going to the farthest reaches 可能 和 they're testing 和 probing 和 确实 at the front edge of discovering 从 the species 那 我们 arguably care 关于 the most, which is humans. Eddie, I have to say, 从 the 首先 time 我们 became friends, 38 years ago?

Dr. Eddie Chang: Something like 那.

安德鲁·休伯曼： Something like 那. I'm almost reluctant to say, so I only reveal it in part 那 Eddie 和 I became friends 因为 both he 和 I shared a love of birds, 和 我们 had a club at 我们的 school of which there were only 二 members, Eddie 和 I.

Dr. Eddie Chang: Small club.

安德鲁·休伯曼： Small club. There was 一 honorary member, 和 there were certain requirements 对于 being in 这 club 那 我们 won't reveal. 我们 took a pact of secrecy, 和 我们're going to obey 那 pact of secrecy. 但 to be sitting here 与 你 today, 对于 me is an absolute thrill. Not just 因为 我们've been friends 对于 那 long 或 那 我们 got reacquainted 通过 literally the halls of medicine 和 science, 但 因为 I 确实 do see what 你're doing as 确实 representing 那 front absolute cutting edge of exploration 和 application. The story of Pancho is 但 一 of 你的 many patients 那 has derived tremendous benefit 从 你的 work. 和 now as a chair of a department, 你 of course work alongside 个体 who are also doing incredible work in the spinal cord, et cetera. So on behalf of myself 和 everyone listening, I just 确实 want to thank 你 对于 joining us today to share 这 information. 我们 会 certainly have 你 back 因为 there's an entire list of other questions 我们 didn't have time to get to, 但 also just 对于 the work 你 do. It's truly spectacular.

Dr. Eddie Chang: Andrew, thanks so much. I'm 非常 humbled, basically, by what 你 just said, 和 I feel 那 it's 确实 an extraordinary honor, actually, 和 privilege to be here 与 你 和 reconnect 和 talk 关于 all 这些 ideas. It's probably not random 那 我们 ended up in 相似的 spots 和 interests, I think, when 我们 were kids. It starts 与 some deep interests 和 kind of nerding out on topics, 和 it's probably not a coincidence 那 我们 have such deep interests in 这 work now. I just feel 确实 lucky to be able to do what I do. It's fun every 天, almost every 天, be able to go to work 和 take care of folks 和 learn at the same time, 和 then just close the loop. How do 我们 apply the knowledge 那 我们 learn 一 天 to someone who comes in next 周? It's 确实 fun. 和 我们 don't know everything. 我们're not even close to it. 但 the journey to figure 这 out is 确实 extraordinary. Like 你 said, it's exploring new lands, literally in the operating room when I'm looking at the exposed cortex, trying to understand, is it safe to walk down 这 part of the cortical landscape 或 这 other trail? Which 一 is going to be the 一 那 is going to be safe versus the other 那 结果 in paralysis 和 inability to talk? Well, maybe I shouldn't call it fun, 但 it's 非常 重要, too, in addition to being 确实 intellectually 重要 对于 how 我们 understand how the 大脑 works. 和 so, yeah, I feel just 确实 lucky to be in 那 opportunity.

安德鲁·休伯曼： 和 我们're lucky to have 你 being 一 of the 人们 doing it, so thank 你 ever so much.

Dr. Eddie Chang: Thanks.

安德鲁·休伯曼： Thank 你 对于 joining me today 对于 my discussion 与 Dr. Eddie Chang. If 你'd like to learn 更多 关于 his 研究 进入 the neuroscience of speech 和 language 和 bioengineering, his treatment of epilepsy, 和 other aspects 和 diseases 和 disorders of the 大脑, please check out the links in 我们的 show note captions. 我们 have links to his laboratory website, his clinical website, 和 other resources related to his critical 研究 as well. If 你're learning 从 和 are enjoying the Huberman Lab 播客, please subscribe to 我们的 YouTube channel. 那's a terrific zero-cost way to support us. In addition, please subscribe to the Huberman Lab 播客 on Spotify 和 Apple. 和 on both Spotify 和 Apple, 你 also have the opportunity to leave us up to a five-star review. If 你 have questions 对于 us 或 comments 关于 the information 我们've covered 或 suggestions 关于 future guests, please put 那些 in the comments section on YouTube. 我们 do read all the comments. Please also check out the sponsors mentioned at the beginning of today's episode. 那's the best way to support the Huberman Lab 播客. Not so much today, 但 in many previous episodes of the Huberman Lab 播客, 我们 talk 关于 supplements. While supplements aren't necessary 对于 everybody, many 人们 derive tremendous benefit 从 them 对于 things like 增强 sleep 和 专注 和 激素 optimization. The Huberman Lab 播客 has partnered 与 Momentous Supplements. If 你'd like to see the supplements 那 the Huberman Lab 播客 has partnered 与 Momentous on, 你 可以 go to livemomentous, spelled O-U-S, so livemomentous.com/huberman, 和 there 你'll see a number of the supplements 那 我们 talk 关于 regularly on the podcast. I 应该 just mention 那 那 catalog of supplements is constantly being updated. As mentioned at the beginning of today's episode, the Huberman Lab 播客 has now launched a premium channel. 那 premium channel 会 feature monthly AMAs, 或 Ask Me Anythings, where I answer 你的 questions in depth, as well as other premium resources. If 你'd like to subscribe to the premium channel, 你 可以 simply go to hubermanlab.com/premium. I 应该 mention 那 the proceeds 从 the premium channel go to support the standard Huberman Lab 播客, which 会 continue to be 释放了 every Monday per usual, as well as supporting various 研究 projects done on humans to create the sorts of tools 对于 心理健康, 身体健康, 和 表现 那 你 hear 关于 on the Huberman Lab 播客. Again, it's hubermanlab.com/premium to subscribe. It's $10 a month 或 $100 per year. If 你 haven't already subscribed to 我们的 zero-cost newsletter, 我们 have what is called the Neural Network Newsletter. 你 可以 subscribe by going to hubermanlab.com, go to the menu, 和 click on Newsletter. 那些 newsletters include summaries of podcast episodes, lists of tools 从 the Huberman Lab 播客, 和 if 你'd like to see previous newsletters 我们've 释放了, 你 可以 also just go to hubermanlab.com, click on Newsletter in the menu, 和 你'll see various downloadable PDFs. If 你 want to sign up 对于 the newsletter, 我们 just ask 对于 你的 email. 我们 do not share 你的 email 与 anybody, 和 again, it's completely zero cost. If 你're not already following me on social media, it's hubermanlab on Twitter, on Facebook, 和 on Instagram. 和 at all 三 of 那些 places, I cover topics 和 subject matter 那 are sometimes overlapping 与 the information covered on the Huberman Lab 播客, 但 那's 经常 distinct 从 information on the Huberman Lab 播客. Again, it's hubermanlab on all social media channels. Thank 你 once again 对于 joining me today 对于 the discussion 关于 the neuroscience of speech, language, epilepsy, 和 much 更多 与 Dr. Eddie Chang. 和 as 总是, thank 你 对于 你的 interest in science.