Huberman Lab - Dr. Erich Jarvis: The Neuroscience of Speech, Language & Music

Episode Date: August 29, 2022

My guest this episode is Dr. Erich Jarvis, PhD—Professor and the Head of the Laboratory of Neurogenetics of Language at Rockefeller University and Investigator with the Howard Hughes Medical Institu...te (HHMI). Dr. Jarvis’ research spans the molecular and genetic mechanisms of vocal communication, comparative genomics of speech and language across species and the relationship between speech, language and movement. We discuss the unique ability of humans (and certain animal species) to learn and communicate using complex language, including verbal speech production and the ability to interpret both written and spoken language. We also discuss the connections between language, singing and dance and why song may have evolved before language. Dr. Jarvis also explains some of the underlying biological and genetic components of stutter/speech disorders, non-verbal communication, why it's easiest to learn a language as a child and how individuals can learn multiple languages at any age. This episode ought to be of interest to everyone interested in the origins of human speech, language, music and culture and how newer technology, such as social media and texting, change our brains.  For the full show notes, visit hubermanlab.com. Thank you to our sponsors AG1 (Athletic Greens): https://athleticgreens.com/huberman LMNT: https://drinklmnt.com/huberman Supplements from Momentous https://www.livemomentous.com/huberman Timestamps (00:00:00) Dr. Erich Jarvis & Vocal Communication (00:03:58) Sponsors: AG1, LMNT (00:08:01) Speech vs. Language, Is There a Difference?   (00:10:55) Animal Communication, Hand Gestures & Language  (00:15:25) Vocalization & Innate Language, Evolution of Modern Language     (00:21:10) Humans & Songbirds, Critical Periods, Genetics, Speech Disorders  (00:27:11) Innate Predisposition to Learn Language, Cultural Hybridization (00:31:34) Genes for Speech & Language (00:35:49) Learning New or Multiple Languages, Critical Periods, Phonemes  (00:40:47) Sponsor: AG1 (00:42:52) Semantic vs. Effective Communication, Emotion, Singing (00:47:32) Singing, Link Between Dancing & Vocal Learning  (00:52:55) Motor Theory of Vocal Learning, Dance  (00:55:03) Music & Dance, Emotional Bonding, Genetic Predispositions (01:04:11) Facial Expressions & Language, Innate Expressions (01:09:35) Reading & Writing  (01:15:13) Writing by Hand vs. Typing, Thoughts & Writing (01:20:58) Stutter, Neurogenetics, Overcome Stutter, Conversations (01:26:58) Modern Language Evolution: Texting, Social Media & the Future (01:36:26) Movement: The Link to Cognitive Growth  (01:40:21) Comparative Genomics, Earth Biogenome Project, Genome Ark, Conservation (01:48:24) Evolution of Skin & Fur Color (01:51:22) Dr. Erich Jarvis, Zero-Cost Support, YouTube Feedback, Spotify & Apple Reviews, Momentous Supplements, AG1 (Athletic Greens), Instagram, Twitter Neural Network Newsletter, Huberman Lab Clips Title Card Photo Credit: Mike Blabac Disclaimer

Transcript
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Starting point is 00:00:00 Welcome to the Uberman Lab podcast where we discuss science and science-based tools for everyday life. I'm Andrew Uberman and I'm a professor of neurobiology and Ophthalmology at Stanford School of Medicine. Today my guest is Dr. Eric Jarvis. Dr. Jarvis is a professor at the Rockefeller University in New York City and his laboratory studies the neurobiology of vocal learning, language, speech disorders, and remarkably the relationship between language, music, and movement in particular dance. His work spans from genomics, so the very genes that make up our genome and the genomes of other species that speak and have language, such as songbirds and parrots. All the way up to neural circuits that is the connections in
Starting point is 00:00:49 the brain and body that govern our ability to learn and generate specific sounds and movements coordinated with those sounds including hand movements and all the way up to cognition. That is our ability to think in specific ways based on what we are saying and the way that we comprehend what other people are saying, singing and doing. As you'll soon see, I was immediately transfixed and absolutely enchanted by Dr. Jarvis' description of his work and the ways that it impacts all the various aspects of our lives. For instance, I learned from Dr. Jarvis that as we read, we are generating very low level
Starting point is 00:01:28 of motor activity in our throat. That is, we are speaking the words that we are reading at a level below the perception of sound or our own perception of those words. But if one were to put an amplifier to measure the firing of those muscles in our vocal cords, we'd find that as we're reading information, we are actually speaking that information. And as I learn and you'll soon learn, there's a direct link between those species in the
Starting point is 00:01:54 world that have song and movement, which many of us would associate with dance and our ability to learn and generate complex language. So for people with speech disorders, like stutter or for people who are interested in multiple language learning, bilingual, trilingual, et cetera. And frankly, for anyone who is interested in how we communicate through words written or spoken,
Starting point is 00:02:18 I'm certain today's episode is going to be an especially interesting and important one for you. Dr. Jarvis' work is so pioneering that he has been awarded truly countless awards. I'm not gonna take our time to list off all the various important awards that he's received, but I should point out that in addition to being a decorated professor at the Rockefeller University, he is also an investigator
Starting point is 00:02:38 with the Howard Hughes Medical Institute, the so-called HHMI. And for those of you that don't know, HHMI investigators are selected on an extremely competitive basis, that they have to re-up, that is, they have to recompete every five years, they actually receive a grade every five years that dictates whether or not they are no longer a Howard Hughes investigator, whether or not they can advance to another five years funding for their important research.
Starting point is 00:03:05 And indeed, Howard Hughes and Vescares are selected not just for the rigor of their work, but for their pioneering spirit and their ability to take on high risk, high benefit work, which is exactly the kind of work that Dr. Jarvis has been providing for decades now. Again, I think today's episode is one of the more unique and special episodes that we've had on the Heurban Lab podcast. I single it out because it really spans from the basic to the applied and Dr. Jarvis' story is an especially unique one in terms of how he arrived at becoming a neurobiologist. So for those of you that are interested in personal journey and personal story, Dr. Jarvis' is truly a special and important one. Before we begin, I'd like to emphasize that
Starting point is 00:03:44 this podcast is separate from my teaching and research roles at Stanford. It is, however, part of my desire and effort to bring zero cost to consumer information about science and science-related tools to the general public. In keeping with that theme, I'd like to thank the sponsors of today's podcast. Our first sponsor is Element.
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Starting point is 00:05:07 And now, for my discussion with Dr. Eric Jarvis. Eric, it's so great to have you here. Thank you. Very interested in learning from you about speech and language. And even as I asked the question, I realized that a lot of people, including myself, probably don't fully appreciate
Starting point is 00:05:24 the distinction between speech and language. Right, speech, I think of a lot of people, including myself, probably don't fully appreciate the distinction between speech and language. Speech, I think, of as the motor patterns, the production of sound that has meaning, hopefully, and language, of course, come in various languages and varieties of ways of communicating. But in terms of the study of speech and language and thinking about how the brain organizes speech and language,
Starting point is 00:05:46 what are the similarities, what are the differences, how should we think about speech and language? Yeah, well, I'm glad you, you know, inviting me here and I'm also glad to get that first question which I couldn't consider a provocative one. The reason why I've been struggling, what is the difference with speech and language many years, and realize why my struggling is because there are behavioral terms, what's
Starting point is 00:06:11 called psychologically psychology developed kind of terms, that don't actually align exactly with brain function. And the question is there is distinction between speech and language. And when I look at the brain of work that other people have done, work we have done, also comparative with animal models like those who can imitate sounds like parrots and so on birds, I start to see there really isn't such a sharp distinction. So to get at what I think is going on, let me tell you how some people think of it now, that there's a separate language module in the brain that has all the algorithms and computations that influence the speech pathway on how to produce sound and the auditory pathway on how to perceive
Starting point is 00:06:57 and interpret it for speech or for, you know, sound that we call speech. And it turns out, I don't think there is any good evidence for a separate language module. Instead, there is a speech production pathway that's controlling our learnings, controlling our job muscles that has built within it all the complex algorithms for spoken language. And there's the auditory pathway that has built within it all the complex algorithms for spoken language. And there's the auditory pathway that has built within it all the complex algorithms for understanding speech,
Starting point is 00:07:31 not separate from a language module. And this speech production pathway is specialized to humans and parrots and songbirds, whereas this auditory perception pathway is more ubiquitous amongst the animal kingdom and this is why dogs can understand sit. See, aren't they say, come here boy, get the ball and so forth. Dogs can understand several hundred human speech words.
Starting point is 00:07:56 Great apes, you can teach them for several thousand, but they can't say a word. Fascinating. Because you've raised a number of animal species early on here, and because I have a, basically, an obsession with animals since the time I was very small, I have to ask which animals have language, which animals have modes of communication that are sort of like language. I've heard whale songs, I don't know what they're saying. They sound very beautiful, but they could be insulting each other for all I know. And they're very well maybe dolphins, birds.
Starting point is 00:08:34 I mean, what do we understand about modes of communication that are like language, but might not be what would classically be called language? Yes, right. So, so modes of communication that people would define as language, more in a very narrow definition, they would say production of sound, so speech. But what about the hands, digesting with the hands? What about a bird who is doing aerial displays in the air, communicating information through body language, right? Well, I'm going to go back to the brain. So what I think is going on is for spoken language, we're using the speech pathway in all the complex algorithms there. Next to the brain regions that are controlling spoken language are the brain regions for gesturing with the hands. And that hand parallel pathway has also complex
Starting point is 00:09:31 algorithms that we can utilize. And some species are more advanced in these circuits, whether it's sound or gesturing with hands, and some are less advanced. Now, we humans and a few others are the most advanced for the speech sounds or the spoken language, but a non-human primate can produce gesturing in a more advanced form than they can produce sound. I'm not sure I got that across clearly, just to say that humans are the most advanced at spoken language, but not necessarily as big a difference at gestural language compared to some of the species. Very clear and very interesting and immediately prompts the question, have there been brain imaging or other sorts of studies evaluating neural activity in the context of your cultures and languages at least that I associate with a lot of hand movement like Italian versus
Starting point is 00:10:29 I don't know Maybe you could give us some examples of cultures where language is not associated with as much overt hand movement. Yes So as you and I are talking here today and people who are listening but can't see us We're actually gesturing with our hands. As we talk, without knowing it, we're doing it unconsciously. And if we were talking on a telephone, I would have one hand here and I'd be gesturing with the other hand, without even you seeing me, right?
Starting point is 00:10:58 And so why is that? Some have argued and I would agree with, based upon what we've seen, is that there is an evolutionary relationship between the brain pathways that control speech production and gesturing. And the brain regions, I mentioned, are directly adjacent to each other. And why is that? I think that the brain pathways that control speech evolved out of the brain pathways that control body movement. And that's when you talk about Italian, French, English, and so forth, each one of those languages
Starting point is 00:11:33 come with a learned set of gestures that you can communicate with. Now, how is that related to other animals? Well, Coco Guerrilla, who has raised with humans for 39 years, more, learned how to do gesture communication, learn how to sign language, so to speak, right? But Coco couldn't produce those sounds.
Starting point is 00:11:56 Coco could understand them as well, by seeing somebody sign, or hearing somebody produce speech, but Coco couldn't produce it with her voice. And so what's going on there is that a number of species, not all of them, a number of species have motor pathways in the brain where you can do learned gesturing, rudimentary language if you want to say with your limbs, even if it's not as
Starting point is 00:12:21 advanced as humans, but they don't have this extra brain pathway for the sound. So they can't gesture with their voice in the way that they gesture with their hands. I see. One thing that I've wondered about for a very long time is whether or not primitive emotions and primitive sounds are the early substrate of language. And whether or not there's a bridge that we can draw and primitive sounds are the early substrate of language.
Starting point is 00:12:45 And whether or not there's a bridge that we can draw between those in terms of just the basic respiration systems associated with different extreme feelings. Here's the way I'm imagining this might work. When I smell something delicious, I typically inhale more and I might say, hmm, or something like that. Whereas if I smell something putrid, I typically turn away, I rinse, and I will exhale, you know, or sort of like, turn away, trying to not ingest those molecules or inhale those molecules. I could
Starting point is 00:13:20 imagine that these are the basic dark and light contrasts of the language system. And as I say that, I'm saying that from the orientation of a vision scientist who thinks of all visual images built up in a very basic way of a hierarchical model of the ability to see dark and light. So I could imagine this kind of primitive to more sophisticated pyramid of sound to language. Is this a crazy idea? Do we have any evidence this is the way it works? No, it's not a crazy idea. And in fact, you hit upon one of the key distinctions in the field of research that I started out in, which is vocal learning research. So for vocal communication, you have most vertebrate species vocalized,
Starting point is 00:14:11 but most of them are producing innate sounds that they're born with producing, that is babies crying, for example, or dogs barking. And only a few species have learned vocal communication, the ability to imitate sounds. And that is what makes spoken language special. When people think of what's special about language, it's to learn vocalizations.
Starting point is 00:14:36 It's what that is, what's rare. And so this distinction between a nateness and learned is more of a bigger dichotomy when it comes to vocalizations than for other behaviors in the animal kingdom. And when you go in the brain, you see it there as well. And so all the things you talked about, the breathing, the grunting, and so forth, a lot of that is handled by the brainstem circuits, you know, right around the level of your neck and below, like a reflex, kind of thing. So, or even some emotional aspects of your behavior in the hypothalamus and so forth. But for a learned behavior, learning how to speak,
Starting point is 00:15:19 learning how to play the piano, teaching a dog to learn how to do tricks is using the four brain circuits. And what has happened is that there's a lot of four brain circuits that are controlling learning how to move body parts in these species, but not for the vocalizations. But in humans and in parrots and some other species, somehow we acquired circuits where the four brain has taken over the brainstem, and now using that brainstem, not only to produce the innate behaviors or vocal behaviors, but the learned ones as well. Do we have any sense of when
Starting point is 00:15:54 modern or sophisticated language evolved, you know, thinking back to the species that we evolved from, and even within homo sapiens, has there been an evolution of language? Has there been a devolution of language? Yeah. Yeah, I would say, and to be able to answer that question, it does come with the caveat that I think we humans overrate ourselves when compared to other species. And so it makes ourselves when compared to other species. And so it makes even scientists go astray in trying to hypothesize when you've such a don't find fossil evidence of language that easily in out there in terms of what happened in the past.
Starting point is 00:16:39 We, amongst the primates, which we humans belong to, we are the only ones that have this advanced vocal learning ability. Now when you, it was assumed that it was only homo sapiens, then you can go back in time now based upon genomic data, not only of us living humans, but of the fossils that have been found for homo sapiens, of Neanderthals, of Denysovian individuals, and discover that our human ancestors supposedly hybridize with these other hominid species. And it was assumed that these other hominid species don't learn how to imitate sounds.
Starting point is 00:17:24 I don't know of any species today that's a vocal learner that can have children with a non-vocal learning species. I don't see it, doesn't mean it didn't exist. And when we look at the genetic data from these ancestral hominids, that, you know, where we can look at genes that are involved in learning vocal communication, they have the same sequence as we humans do
Starting point is 00:17:49 for genes that function in speech circuits. So I think Neanderthals had spoken language. I'm not going to say it's as advanced as what it is in humans, I don't know. But I think it's been there for at least between 500,000 to a million years that our ancestors had this ability. And that we've been coming more and more advanced with it culturally and possibly genetically. But I think it's evolved sometime in the last 500,000 to a million years.
Starting point is 00:18:16 Incredible. Maybe we could talk a little bit more about the overlap between brain circuits that control language and speech and humans and other animals. I was weaned in the neuroscience era where bird song and the ability of birds to learn their tutors song was, it was and still is a prominent field, subfield of neuroscience. And then of course, neuroimaging of humans, speaking and learning, et cetera.
Starting point is 00:18:47 And this notion of a critical period, a time in which language is learned more easily than it is later in life. And the names of the different brain areas were quite different. It one opens the textbooks we hear, Vernake's and Broca's for the humans, and you look at the birds of it, I remember, you know, at Rob, Robust Archstriadome, AriaX, etc. But for most of our listeners, those names won't mean a whole lot. But in terms of homologies between areas, in terms of function, what do we know? And how similar are different different are the brain areas controlling
Starting point is 00:19:26 speech and language and say a songbird and a young child? Yeah. So going back to the 1950s or even a little earlier, and Peter Moller and others who got involved in neuroethology, the study of neurobiology of behavior in a natural way, right? They start to find that, behaviorally, there are these species of birds,
Starting point is 00:19:50 like sawmbears and parrots, and now we also know hummingbirds, just three of them, out of the 40-something bird groups out there on the planet, orders, that they can imitate sounds like we do. And so that was a similarity. In other words, they had this kind of behavior
Starting point is 00:20:04 that's more similar to us than chimpanzees have with us, or then chickens have with them, right? They're closer relatives. And then they discovered even more similarities, these critical periods, that if you remove a child, unfortunately happens where a child is feral, and it's not raised with human, and goes through their puberty phase of growth, becomes hard for them to learn a language as an adult. So there's this critical period where you learn best.
Starting point is 00:20:32 And even later on, when you're in regular society, it's hard to learn. Well, the St. Birds undergo these same thing. And then it was discovered that if they become deaf, we humans become deaf, our speed starts to deteriorate without any kind of therapy. If a non-human primate or, you know, or let's say a chicken becomes deaf, their vocalizations don't deteriorate,
Starting point is 00:20:56 very little at least. Well, this happens in the vocal learning birds. So there were all these behavioral parallels that came along in a package, and then people looked into the brain, Fernando Nautaba, my former PhD advisor, and began to discover the area X you talked about, the robust nucleus of the arcopalium. And these brain pathways were not found in the species who couldn't imitate. So there was a parallel here. And then jumping many years later, I started to dig down
Starting point is 00:21:27 into these brain circuits to discover that these brain circuits have parallel functions with the brain circuits for humans, even though they're by a different name, like Broca's and Larinja motor cortex. And most recently, we discovered not only the actual circuitry and the connectivity are similar, but the underlying genes that are Express in these brain regions in a specialized way different from the rest of the brain are also similar
Starting point is 00:21:52 between humans and sawmvers and parrots. So all the way down to the genes and now we're finding the specific mutations are also similar, not always identical but similar. Which indicates remarkable convergence for a so-called complex behavior in species separated by 300 million years from a common ancestor. And not only that, we are discovering that mutations in these genes that cause speech deficits in humans, like in Fox P2, if you put those same mutations or similar type of deficits in these vocal learning birds, you get similar deficits. So convergence of the behavior is associated with similar genetic disorders of the behavior.
Starting point is 00:22:33 Incredible. I have to ask, do hummingbirds sing or do they hum? Hummingbirds hum with their wings and sing with their serings. In a coordinated way. In a coordinated way. In a coordinated way. There's some species of hummingbirds that actually will, Doug Ashweller showed this, that will flap their wings and create a slapping sound with their wings
Starting point is 00:22:58 that's in unison with their song. And you would not know it, but it sounds like a particular syllable in their songs, even though it's their wings and their voice at the same time. Hummingbirds are clapping to their song. Clapping, they're snapping their wings together in unison with a song to make it like, if I'm going, that, that, that, that, that, that, that, that, you know, I banged on the table, except they make it almost sound like their voice with their wings. Incredible. that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, that, because they move around so fast and they flip away so fast and these ballistic trajectories. Yeah.
Starting point is 00:23:45 That when you get to see one stationary for a moment, or even just hovering there, you feel like you're extracting so much from their little microcosm of life. But now I realize they're playing music essentially. Right, exactly. And what's amazing about hummingbirds, and I will say vocal learning species in general, is that for whatever reason they seem to evolve multiple complex traits. This idea that evolving language, spoken language in particular comes along with a set of specializations.
Starting point is 00:24:19 When I was coming up in neuroscience, I learned that I think it was the work of Peter Marler that young birds learn songbirds, learn their tutors song, and learn it quite well, but that they could learn the song of another tutor. In other words, they could learn a different, and for the listeners, I'm doing air quotes here, a different language, a different bird song, different than their own species. But never as well as they could learn their own natural genetically linked song. Yes. Genetically linked meaning that they would be like me being
Starting point is 00:24:55 raised in a different culture and that I would learn that the other language, but not as well as I would have learned English. This is the idea. Yes. Is that true? That is true. Yes. And that's what I learned growing up as well, and talked to Peter Mahler himself about before he passed. He used to call it the innate predisposition to learn. Which would be kind of the equivalent in the linguistic community of universal grammar. There is something genetically influencing our vocal communication on top of what we learn culturally. And so there is this balance between the genetic control of speech or a song in these birds
Starting point is 00:25:39 and the learned cultural control. And so yes, if you were to take, I mean, in this case, we actually tried this that Rockefeller later on, take a zebra finch and raise it with a canary, it would sing a song that was sort of like a hybrid in between, we call it a caninch, right? And vice versa for the canary, because there's something different
Starting point is 00:26:04 about their vocal musculature or the circuitry in the brain. And with a zebra finch, even with a closely related species, if you would take a zebra finch young animal, and in one cage next to it, place its own species, adult male, right? And in the other cage, place a Bengaleese finch next to it. It would preferably learn the song from its own species, neighbor. But if you remove its neighbor,
Starting point is 00:26:30 it would learn that Bengali's Finch very well. Fantastic. So it has something to do with also the social bonding with your own species. Incredible. That raises a question that based on something I also heard, but I don't have any scientific, pure-reviewed publication to point to, which is this idea of pigeon, not the bird,
Starting point is 00:26:49 but this idea of when multiple cultures and languages converge in a given geographic area, that the children of all the different native languages will come up with their own language. I think this was in island culture, maybe in Hawaii, called pigeon, which is sort of a hybrid of the various languages that their parents speak at home, and that they themselves speak, and that somehow Pigeon, again, not the bird, but a language called Pigeon for reasons I don't know,
Starting point is 00:27:18 harbors certain basic elements of all language. Is that true? Is that not true? I haven't studied enough myself in terms of pigeons specifically, but in terms of cultural evolution of language and hybridization between different cultures and so forth, even amongst birds with different dialects, and you bring them together. What is going on here is What is going on here is cultural evolution remarkably tracks genetic evolution. So if you bring people from two separate populations together that have been in their separate populations evolutionarily at least for hundreds of generations, so someone speaking Chinese, someone speaking English. And that child then is learning from both of them, yes, that child's going to be able to pick up and merge
Starting point is 00:28:11 phonemes and words together in a way that an adult would it, because why they're experiencing both languages at the same time during their critical period years in a way that adults would not be able to experience. And so you get a hybrid. And the lowest common denominator is going to be what they share. And so the phonemes that they've retained in each of their languages is what's going to be, I imagine, use the most. Interesting. So we've got brain circuits in songbirds and in humans that in many ways are similar, perhaps not in their exact
Starting point is 00:28:51 wiring, but in their basic contour of wiring. And genes that are expressed in both sets of neural circuits in very distinct species that are responsible for these phenomenon we're calling speech and language. What sorts of things are those genes controlling? are responsible for these phenomena we're calling speech and language. What sorts of things are those genes controlling? What I could imagine they were controlling the wiring of connections between brain areas, essentially a map of a circuit.
Starting point is 00:29:16 I still like an engineer on a circuit for speech and language, nature design, for speech and language, but presumably other things too, like the ability to connect motor patterns within the throat, of muscles within the throat, when the control of the tongue. I mean, what are these genes doing? You're pretty good. Yeah, you've made some very good guesses there that make sense. So yes, one of the things that differ in the speech pathways of us, and these
Starting point is 00:29:46 song pathways of birds, is some of the connections are fundamentally different than the surrounding circuits, like a direct cortical connection from the areas that control vocalizations in the cortex, the motor neurons that control the larynx in humans or the serings and birds. And so we actually made a prediction that since some of these connections differ, we're gonna find genes that control neuro-connectivity and that specialize in that function, that differ.
Starting point is 00:30:14 And that's exactly what we found. Genes that control what we call axon guidance and form and shouldn't connections. And what was interesting was sort of in the opposite direction that we expected. That is, some of these interesting, it was sort of in the opposite direction that we expected. That is, some of these genes, actually a number of them, that control neuro-connectivity, were turned off in the speech circuit. All right.
Starting point is 00:30:35 And it didn't make sense to us at first, and so we started to realize the function of these genes are to repel connections from forming. So repulsive molecules. And so when you turn them off, they allow certain connections to form that normally would have not formed. So by turning it off, you get a gain of function for speech, right?
Starting point is 00:30:55 Other genes that surprised us were genes involved in calcium buffering, neuroprotection, like a parvalveamine or a heat shock protein. So when your brain gets hot, these proteins turn on. And we couldn't figure out for a long time, why is that the case? And then the idea popped to me one day and said, ah, when I heard the larynx is the fastest firing muscles in the body, all right? In order to vibrate sound and modulate sound in the way we do, you have to move those muscles
Starting point is 00:31:28 three to four to five times faster than just regular walking or running. And so, when you stick electrodes in the brain areas that control learn vocalizations in these birds and I think in humans as well, those neurons are firing at a higher rate to control these muscles. And so what is that gonna do? You're gonna have lots of toxicity in those neurons unless you up-regulate molecules that take out the extra load that is needed to control the larynx.
Starting point is 00:31:59 And then finally a third set of genes that are specialized in these speed circuit are involved in neuroplasticity. Neuroplasticity, meaning allowing the brain circuits to be more flexible so you can learn better. And why is that? I think learning how to produce speech is a more complex learning ability than, say, learning how to walk or learning how to do tricks and jumps and so forth
Starting point is 00:32:26 that dogs do. Yeah, it's interesting as you say that because I realized that many aspects of speech are sort of reflexive. I'm not thinking about each word I'm going to say I just they just sort of roll out of my mouth. Hopefully with some forethought we both know people that seem to speak think less fewer synapses between their brain and their mouth than others, right? A lot of examples out there. And some people are very deliberate in their speech. But nonetheless, that much of speech has to be precise, and some of it less precise. In terms of plasticity of speech, and the ability to learn multiple languages, but even just one language. What's going on in the critical period, the so-called critical period?
Starting point is 00:33:07 Why is it that, so my niece speaks Spanish, she's Guatemalan speaks Spanish and English, incredibly well, she's 14 years old. I've struggled with Spanish my whole life. My father's bilingual, my mother's not, I've tried to learn Spanish as an adult. It's really challenging. I'm told that had I learned it when I was eight,
Starting point is 00:33:26 I would be better off. That's right. Or it would be installed within me. So the first question is, is it easier to learn multiple languages without an accent early in life? And if so, why? And then the second question is, if one can already speak more than one language as a consequence of childhood learning,
Starting point is 00:33:44 is it easier to acquire new languages later on? So the answer to both of those questions is yes. But to explain this, I need to let you know, actually the entire brain is undergoing a critical period development, not just the speech pathways. And so it's easier to learn how to play a piano. It's easier to learn how to write a bike for the first time and so forth, as a young child than it is later in life.
Starting point is 00:34:15 What I mean easier in terms of when you start from, you start from first principles of learning something. So the very first time if you're going to learn Chinese as a child versus the very first time you learn Chinese as an adult, or learning piano as a child versus an adult. But the speech pathways, or let's say speech behavior, I think has a stronger critical period change to it than other circuits. And why what's going on there in general? If you... Why do you need a critical period to make you more stable, to make you more stubborn, so to speak? The reason I believe is that the brain can only hold so much information.
Starting point is 00:35:04 your brain can only hold so much information. And if you are undergoing rapid learning to acquire new knowledge, you also have to, you know, dump stuff, put in memory or information in the trash, like in a computer. You only have so many gigabases of memory. And so therefore, plus, also for survival, you don't want to keep forgetting things. And so the brain is designed, I believe, to undergo this critical period and solidify the circuits with what you learned as a child and you use that for the rest of your life. And we humans stay even more plastic in our brain functions, controlled by a gene called SRGAP2.
Starting point is 00:35:46 We have an extra copy of it that leads out speech circuit and other brain regions in a more immature state throughout life compared to other animals. So we're more immature. We're still juvenile light compared to other animals. I knew it. But we still go through the critical periods like they all do.
Starting point is 00:36:02 And now the question you asked about, if you learn more languages as a child, is it easier to learn as an adult? And that's a common finding out there in the literature. There's some that argue against it. But for those that support it, the idea there is, you are born with a set of innate sounds you can produce a phonemes,
Starting point is 00:36:24 and you narrow that down, because not all languages use all of them. And so you narrow down the ones you use to string the phonems together and the words that you learn, and you maintain those phonems as an adult. And here comes along another language that's using those phonems or in different combinations you're not used to, and therefore it's like starting from first principles. But if you already have them in multiple languages that you're using, then it makes it easier to use them in another third or fourth language.
Starting point is 00:36:55 I see. Incredible. So it's not like your brain has maintained greater plasticity is your brain has maintained greater ability to produce different sounds that then allows you to learn another language faster. Got it. Are the hand gestures associated with sounds or with meanings of words? I think the hand gestures associated with both the sounds and the meaning of when I say sound like, if you are really angry, and you are making a loud screaming noise,
Starting point is 00:37:30 you may make hand gestures that are look like you're going to beat the wall, because you're making loud sounds and loud gestures. But if you want to explain something like, come over here. What I just do now to you for those who can't see me, I swung my hand towards you and swung it here to me. That has a meaning to it, to come here.
Starting point is 00:37:52 So just like with the voice, the hand gestures are producing both, both qualities of sound. And for people that speak multiple languages, especially those that learn those multiple languages early in development, do they switch their patterns of motor movements according to, let's say, going from Italian to Arabic or from Arabic to French in a way that matches the precision of language that they're speaking. You know what? You just asked me a question. I don't know the answer to.
Starting point is 00:38:25 I would imagine that would make sense because of switching in terms of sometimes people might call this code switching even different dialects of the same language. Could you do that with your gestures? I imagine so, but I really don't know if that's true or not. I certainly don't know from my own experience because I only speak one language. I'd like to take a quick break and acknowledge one of our sponsors, Athletic Greens. Athletic Greens, now called AG1,
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Starting point is 00:39:34 make sure that all of my foundational nutritional needs are met. And it tastes great. If you'd like to try athletic greens, you can go to atlettegreens.com slash Huberman and they'll give you five free travel packs that make it really easy to mix up athletic greens while you're on the road in the car on the plane, etc. And they'll give you a year supply of vitamin D3K2. Again, that's atletitgreens.com slash Huberman to get the five free travel packs and the year supply of vitamin D3K2. To go a little bit into the abstract, but not too far. What about modes of speech and language
Starting point is 00:40:08 that seem to have a depth of emotionality and meaning but for which it departs from structured language? Here's what I mean, poetry. I think of musicians like there's some Bob Dylan songs that to me, I understand the individual words. I like to think there's an emotion associated with it. At least I experienced some sort of emotion and I have a guess about what he was experiencing. But if I were to just read it linearly without the music and without him singing it or somebody singing it like him, it wouldn't hold any meaning. So in other words, words that seem to have meaning but not associated with language but somehow tap into an emotionality.
Starting point is 00:40:52 Yep, absolutely. So we call this different semantic communication, communication with meaning, and effective communication, communication that has more of an emotional feeling content to it, but not with the semantics. The two can be mixed up, like with singing words that have meaning, but also have this effective emotional, you just love the sound of the singer that you're hearing. And initially, you know, psychologists, scientists in general thought that these were going to be controlled by different brain circuits. And it is the case, there are emotional brain centers and hypothalamus in the single-it cortex and so
Starting point is 00:41:38 forth that do give tone to the sounds. But I believe based upon imaging work and work we see in birds, when birds are communicating semantic information in their sounds, which is not too often, but it happens versus effective communication sing because I'm trying to attract the mate, my courtship song or defend my territory. It's the same brain circuits. It's the same speech, like, or song circuits
Starting point is 00:42:06 are being used in different ways. A friend of mine who's also a therapist said to me, it's possible to say, I love you with intense hatred and to say, I hate you with intense love. And reminding me that it's possible to hear both of those statements in either way. So I guess it's not just limited to song or poetry. It also, there's something about the intention and the emotional context in which
Starting point is 00:42:35 something's spoken that can heavily shape the way that we interpret what we hear. That's right. And I consider all of that actually meaning, even though I define it as people commonly do semantic and effective communication, effective communication to say I hate you, but men love, right, is does have emotional meaning to it. And so, you know, one's more like an object kind of meaning or an abstract kind of meaning. There's several other points here I think it's important for those listening out there to hear. Is that when I say also this effective and semantic communication being used by similar brain circuits, it also matters the side of the brain. In birds and in humans, there's left-right dominance for learned communication, learned sound communication.
Starting point is 00:43:30 So the left in us humans is more dominant for speech, but the right has a more balance for singing or processing musical sounds as opposed to processing speech. Both get used for both reasons. And so when people say your right brain is your artistic brain and your left brain is your thinking brain, this is what they're referring to. And so that's another distinction. The second thing that's useful to know is that all vocal learning species use their learned sounds for this emotional, effective kind of communication.
Starting point is 00:44:07 But only a few of them, like humans and some parrots and dolphins, use it for the semantic kind of communication, calling speech. And that has led a number of people to hypothesize that the evolution of spoken language of speech evolved first for singing, for this more emotional kind of made attraction, like the Jennifer Lopez, the Ricky Martin kind of songs, and so forth. And then later on, it became used for abstract communication like we're doing now. Interesting. Well, that's a perfect segue for me to be able to ask you about your background and motor control not only of the hands but of the body. So you have a number of important distinctions to your name, but one of them is that you were a member of the Alvin Ailey dance school of dance. That's right. So you're an accomplished and quite able dancer, right? Tell us a little bit about your background in the world of dance and as how it informs your
Starting point is 00:45:15 interest in neuroscience, excuse me, and perhaps even how it relates specifically to your work on speech and language. Yes. Well, it's interesting. And this kind of history even goes before my time. So in my family, my mother and father's side, they both went to the high school of music and art here in New York City. And particularly in my mother's family, going back multiple generations, there were singers. And I even did my family genealogy and found out not only,
Starting point is 00:45:41 we have some relationships to some well-known singers, distant relationships like the Lonious Monk, but going back to the plantations in North Carolina and so forth, my ancestors were singers in the church for the, you know, the towns and so forth. And this somehow got passed on multiple generations to my family. And I thought I was going to grow up and be a famous singer, right? And me and my brothers and sister formed a band, one were kids and so forth. But it turned out that I didn't inherit these singing talents of some of my other family members, even though, you know, it was, you know, okay, you know, but not like my brother, or not like my mother, or my aunts, and cousin, Pudifei, who's now a talent
Starting point is 00:46:26 in Native American singer. And so that then influenced me to do other things. And I started competing in dance contest. Actually, this is around the time of the satan night fever. And I was a teenager. And I started winning dance contest. and I thought, oh, I can dance. And I auditioned for the high school performing arts and I got in here in New York City and got into ballet dance and got in, right? And in thought, if I learned ballet, I can learn everything else.
Starting point is 00:47:00 It was that idea. If you learn something classical, you can teach you for everything else. And I was, yeah, at Alvin-Ali Dance School, Jaffa Ballet Dance School, and at the end of my senior concert, I had this opportunity, you know, auditioned for the Alvin-Ali Dance Company, and I had an opportunity to go to college. And I also fell in love with another passion that my father had, which was science. And so I liked science in high school, and I found an overlap also between the arts and sciences, both required creativity, hard work, discipline, new discovery, both weren't boring to me.
Starting point is 00:47:39 And the one decision I made at that senior dance concert was talking to the Avonali recruiter and thinking about it I have to make a decision and I thought something my mother taught me because she was grown up in the 1960s cultural revolution do something that has a positive impact on society and I thought I can do that better as a dancer than a scientist. So now jump I get into college undergraduate school. I major in molecular biology and mathematics. I decided I want to be a biologist. Get into graduate school when it's a study,
Starting point is 00:48:13 the brain at the Rockefeller University. So I went from Hunter College to Rockefeller University. And so now I got to the brain. And why did I choose the brain is because it controls dancing. But I didn't, there wasn't anybody studying dancing. And I wanted to study the brain, something that it does that's really interesting and complex. And I thought, ah, language is what it does.
Starting point is 00:48:36 You couldn't study that in mice, you couldn't study non-human primates, but these birds do this wonderful thing that Fernando Nautobom was studying at Rockefeller. And so that's what got me into the birds. And then jumping now 15 years later, yeah, that's right, even after I'm into now having my own lab studying vocal learning in these birds
Starting point is 00:48:59 as a model for language and humans, it turns out that, Anipatel, others have discovered that only vocal learning species can learn how to dance. Is that right? That's right. Yes. So I've seen these just scrolling through the files here in my mind. I think about everyone's a while someone was, I loved parrots. Yeah's while someone was sending me
Starting point is 00:49:26 one of these little Instagram or Twitter videos of a parrot doing what looks to me like dance. Typically, it's a cockatoo. That's right. Right. That's right. Even foot stomping to the sound. The famous one called snowball out there. But there are many snowballs out there. They're all the dancing birds.
Starting point is 00:49:42 They're named snowball. That's interesting tactic. So only animals with language dance. They're all the dancing birds are named snowball. That's interesting tactic. So only animals with language dance. Yeah, vocal learning in particular, the ability to imitate sounds. Yes, incredible. Yes, and this now is bringing my life full circle. Right, and so when that was discovered in 2009, at that same time in my lab at Duke,
Starting point is 00:50:07 we discovered that vocal learning brain pathways in songbirds, as well as in humans, and in parrots, like snowball, are embedded within circuit-secondary learning how to move. And that led us to a theory called the brain pathway, or motor theory of vocal learning origin, where the brain pathways for vocal learning and speech evolved by a whole duplication
Starting point is 00:50:32 of the surrounding motor circuits involving learning how to move. Now, how does that explain dance, right? Well, when when snowball the cockatooes are dancing, they're using the brain regions around their speech like circuits to do this dancing behavior. And so what's going on there? What we hypothesize, and now like to test, is that when this, when speech evolved in humans, and the equivalent behavior in parrots and somber, it required a very tight integration
Starting point is 00:51:08 in the brain regions that can hear sound with the brain regions that control your muscles from moving your larynx and tongue and so forth for producing sound. In that type auditory motor integration, we argue that contaminate the surrounding brain regions. And that contamination of the surrounding brain regions now allows us humans, a particular in parades, to coordinate our muscle movements of the rest of the body with sound in the same way we do for speech sounds. Well, so we're speaking with our bodies when we dance. Incredible. And I have to say that as poor as I am at speaking multiple languages, I'm even worse at dancing.
Starting point is 00:51:49 So by guarantee, you're better than a monkey, but not snowball the cock at two. Maybe not snowball. On YouTube, we have a video where there's some scientists dancing with snowball, and you'll see snowballs doing better than some of the scientists. It was also, I'm not the worst of all scientists in dancing. There's always a neuroplasticity. May it save me someday. You said something incredible that I completely believe, even though I have minimum to,
Starting point is 00:52:20 let's just say minimum dancing ability. I can get by at a party or wedding without complete embarrassment, but I don't have any structured training. So the body clearly can communicate with movement as a train dancer and knowing other train dancers. I always think of dance and bodily movement and communication through bodily movement as a form of a wordlessness, like a state of wordlessness. In fact, the few times when I think that maybe I'm
Starting point is 00:52:51 actually dancing modestly well for the context that I'm in, where I see other people dancing, and they seem to just be very much in the movement. It's almost like a state of non-language, It's almost like a state of non-language, non-spoken language. And yet, what you're telling me is that there's a direct bridge at some level between the movement of the body and language. So is there a language of the body that is distinct from the language of speech? And if so, or if not, how do those map onto one another? What does that Venn diagram look like? Yeah. Yeah. So, so let me define first,
Starting point is 00:53:30 dance in this context of vocal learning species. This is the kind of dancing that we are specialized in doing. And other in the vocal learning species, specialized in doing is synchronizing body movements of muscles to the rhythmic beat of music. And for some reason, we like doing it. We like synchronizing to sound and doing it together as a group of people.
Starting point is 00:53:54 And that kind of communication amongst ourselves is more like the effective kind of communication I mentioned earlier, unlike the semantic kind. So we humans are using our voices more for the semantic abstract communication, but we're using learned dance for the effective emotional bonding kind of communication. It doesn't mean we can't communicate semantic information in dance, and we do it, but it's not as popular. Like a ballet in the nutcracker, it is popular
Starting point is 00:54:30 where they are communicating, the Arabian guy comes out, which I was the Arabian guy in the ballet nutcracker, that's how you remember. Yeah, for the Westchester Ballet Company, when I was a teenager. We're trying to communicate meaning in our ballet dance, and it can go on with a whole story and so forth. But people don't interpret that as clearly as speech.
Starting point is 00:54:52 You know, they're seeing the ballet with semantic communication with a lot of emotional content. Whereas you go out to a club, you know, yeah, you're not coming communicating, okay, how you're feeling today. Tell me about your day and so forth. You're trying to synchronize with other people in an effective way. I think that's because the dance brain circuit inherited the more ancient part of the speech circuit, which was for singing.
Starting point is 00:55:21 I always had the feeling that with certain forms of music, in particular opera, but any kind of music where there are some long notes sung, that at some level there was a literal resonance created between the singer and the listener that, or I think of like the deep voice of a Johnny Cash, or where at some level you can almost feel the voice in your own body. And in theory, that could be the vibration of the, or the firing of the frenic nerve controlling the diaphragm for all I know. Is there any evidence that there's a coordination between performer and audience at the level of mind and body? I'm going to say possibly yes.
Starting point is 00:56:13 And the reason why is because I just came back from a conference on the neurobiology of dance. Clearly I'm going to the wrong meetings. The college, the vision science community. I'm so boring. Yes. Well, one of my colleagues to come to Fitch and Jonathan Fritz, they organized a particular section on this conference in Virginia. And this is the first time I was in the room with so many neuroscientists studying the
Starting point is 00:56:37 neurobiology of dance. It's a new field now in the last five years. And there was one lab where they were putting EG electrodes on the dancers, on two different dancers partnering with each other, as well as the audience, seeing the dance. And some argued, okay, if you're listening to the music as well, how you respond, because you're asking a question about music,
Starting point is 00:57:05 and I'm giving you an answer about dance. And what they found is that, you know, the dancers, when they resonate with each other during a dance, or the audience listening to the dancers and the music, there are some resonance going on there that they score as higher resonance. Their brain activity with these wireless EEG signals are showing something different.
Starting point is 00:57:27 And so that's why I say possibly yet, it needs more rigorous study. And you know, this is some stuff they published, but it's not prime time yet, but they're trying to figure this out. I love it. So at least if I can't dance well, maybe I can hear and feel what it is to dance in a certain way. That's right. And this will be some people will think that they, even songs that they hear, and they can almost sing to themselves in their own head.
Starting point is 00:57:56 And they know what they wanted to sound like. And you know, when it really sounds good, what it sounds like, but they can't get their voice to do it. I'm raising, for those listening, I'm raising my hand, no musical ability. Others in my household have tremendous musical ability with instruments and with voice, but not me. Yeah, and so this is one of my selfish goals of trying to find the genetics of why can some people sing really well and some not. I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that.
Starting point is 00:58:26 I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that. I mean, I don't know how to say that.
Starting point is 00:58:42 I mean, I don't know how to say that. I mean, I don't know how to say that. I've been trying to breathe as good as my brother Mark and Victor, you know, for the rest of the whole my entire life. I watch out, Mark and Victor. He's coming for you with neuroscience to back him. Earlier, you said that you discovered that you could dance. That caught my ear. It sounds like you didn't actually have to, I'm not suggesting you didn't work hard at it,
Starting point is 00:59:04 but that at the moment where you discovered it, it just sort of was a skill that you had that up until that point, you didn't target a life in the world of dance. But the fact that you, quote unquote, discovered that you could dance really well and then went to this incredible school of dance and did well tells me that perhaps there is an ability that was built up in childhood and or that perhaps we do all have different genetic leanings for different motor functions. Yeah, well for me there could be both explanations could be possible. For the first I grew up in its family listening to Motown songs, dancing at parties and so forth, family parties, an African-American family basically.
Starting point is 00:59:53 So I grew up dancing from a young child, but this discovery, maybe dancing even more so in terms of a talent, the genetic component, if it really exists, I don't know. With my 23-and-me results, it says I have the genetic substitutions that are associated with high-intensity athletes and fast-pitched muscles. And who knows, maybe that could have something to do with me being able to synchronize my body to rhythmic sounds. Maybe, maybe better than some others. It turns out that my genetics also
Starting point is 01:00:37 show that I have a genetic substitute that makes it hard for me to sing on pitch. And so that does correlate with my, you know, even though I can sing on this pitch especially if I hear a piano or, you know, kind of playing it, but, you know, maybe that's why my siblings, you know, who didn't have that genetic predisposition in his 23-mm results, you know, it could go along with the genetic component as well. I'm imagining family gatherings with 23 and me data and
Starting point is 01:01:05 intense arguments about it and eight and learnability. Yes. Fun. Love to be an attendant. I'm not inviting myself to your Thanksgiving dinner. By the way, I suppose I am. You're welcome, too. Thank you. I'll bring my 23 and me data. I'd love to chat a moment about facial expression because that's a form of motor pattern that, you know, I think for most people out there, just think about smiling and frowning, but there are, of course, you know,
Starting point is 01:01:32 thousands, if not millions, of micro expressions and things of that sort, many of which are subconscious. And we're all familiar with the fact that when what somebody says doesn't match some specific feature of their facial expression that it can call that mismatch can cue our attention, especially among people that know each other very well. you're right eye, twitch to the, you know, a little bit in a way that tells me that you didn't really mean that. This, these kinds of things. Or when the opposite example, when the motionality and the content of our speech is matched to a facial expression,
Starting point is 01:02:16 there's something that's just so wonderful about that because it seems like everything's aligned. Yeah. So how does the motor circuitry that controls facial expression map on to the brain circuits that control language speech and even bodily and hand movements? Yeah. You asked a great question because we both know some colleagues like Winwick Frival at Rockefeller University who studied facial expression and the neurology behind it.
Starting point is 01:02:43 And now we both share some students that were commentering and talk about the same question that you brought up. And what I'm learning a lot is that non-human primates have a lot of diversity in their facial expression like we humans do. And what we know about the neurobiology of brain regions controlling those muscles of the face is that these non-human primates and some other species that don't learn how to imitate the vocalizations, they have strong connections from the cortical regions to the motor neurons that control facial expressions,
Starting point is 01:03:18 but absent connections or weak connections to the motor neurons that control the voice. So I think our diverse facial expression, even though it's more diverse in these non-human primates, there was already a free existing diversity of communication, whether it's intentional or unconscious through facial expression in our ancestors. And on top of that, we humans now add the voice, along with those facial expressions. I see. And in terms of language learning when we're kids, I mean, children, fortunately, are not told
Starting point is 01:03:54 to fake their expressions or to smile when they say I'm happy. So at some point, everybody learns for better, for worse, how to untangle these different components of hand movement, body posture, speech and facial expression. Yes. But in their best form, I would say, assuming that the best form is always, I guess there are instances where, you know, for safety reasons, one might need to feign some of these aspects of language. But in most cases, when those are aligned, it seems like that could reflect that
Starting point is 01:04:29 all the different circuitries are operating in parallel, but that the ability to misalign these is also a powerful aspect to our maturation. I even think of theater, for instance, where deliberate disentangling of these areas is important, but also we know when an actor, when it feels real, and when it looks, like when bad acting is oftentimes
Starting point is 01:04:53 when the facial expression or body posture just doesn't quite match what we're hearing. So are these skills that people that learn and acquire according to adaptability and profession, or do you think that all children and all adults eventually learn how to couple and uncouple these circuits a little bit? Yeah, I think it's this similar argument I mentioned earlier about the innate and the learned for the vocalizations.
Starting point is 01:05:18 And by the way, when I say we humans have facial expressions associated with our vocalizations in a different way than primates, nonhuman primates. It's the learned vocalizations I'm talking about. So there is a common view out there that facial expressions and nonhuman species, like nonhuman primates, or you can have them in birds too, are innate. And so they're reflexive control. I don't believe that. I think there's some learned component to it.
Starting point is 01:05:48 And I think we have more learning component to it as well. But we also have an innate component. And so if you try to put your hands behind your back and hold your fist or even just not, and try to speak and try to communicate, it's actually harder to do. You have to force yourself or put it by your side. This comes naturally.
Starting point is 01:06:07 Facial expressions comes naturally because there is an innate component. And yes, you have to learn how to dissociate the two. Communicate something angry with your hands over your face, but politely with your voice. It's very hard to separate at this too, because there is that innate component that brings them together.
Starting point is 01:06:30 So it's like an email too. You're emailing and someone says something by email, so I can interpret that angrily or gently. And it becomes ambiguous. The facial expressions get rid of that ambiguity. So glad you brought that out out because my next question was, and is about written language. The first question I'll ask is, when you write, either type or write things out by hand, do you hear the content of what you want to write in your head? You just you personally.
Starting point is 01:07:08 you want to write in your head. You just you personally. Yes, I do. Yeah, I, and I know that I do because I was trying to figure out a debate about this issue and trying to resolve the debate with my own self-experimentation on me. I asked that because a quite well-known colleague of ours, Carl Diceroth at Stanford, who's been on this podcast and is, you know, Optogenetics, Fame, and Psychiatry, Fame, et cetera. And I know him. Yeah. He sends his regards.
Starting point is 01:07:30 I bet. It told me that his practice for writing and for thinking involves a quite painful process of forcing himself to sit completely still and think in complete sentences, to force thinking in complete sentences. And when he told me that, I decided to try this exercise. And it's quite difficult. First of all, it's difficult for the reason that you mention, which is that with many
Starting point is 01:07:57 thoughts I want to look around and I start to gesticulate with my hands. So there it is again, the connection between language and hand movement, even if one isn't speaking. And the other part is that challenging is I realize that while we write in complete sentences, most of the time, we'll talk about how that's changing now and texting, etc, that we don't often think in complete sentences, and specifically in simple declarative sentences, that a lot of our thoughts would be, if they were written out onto a page, would look pretty much like passive language that a good copy editor or a good editor would say,
Starting point is 01:08:39 oh, we need to cross this out, make this simple and declarative. So what I'm getting at here is, what is the process of going from a thought to language to written word? And I also wanted to touch on hand written versus typed, but thought to language to written word. What's going on there? What do we know about the neural circuitry?
Starting point is 01:09:02 And I was going to ask why is it so hard, but now I want to ask, why is this even possible? It seems like a very challenging neural computational problem. Yeah, yeah. And from coming from the linguistic world, and even just the regular neurobiology world, going back to something I said before is about a separate language module in the brain.
Starting point is 01:09:23 There was this thought or hypothesis that this language module has all these complex algorithms to them. And they're signaling to the speed circuit, how to produce the sounds, the hand circuit, how to write them, or gesture the visual pathway on how to interpret them from reading, and the auditory pathway for listening.
Starting point is 01:09:46 I don't think that's the case, all right? And you know, that this thinking where there's this internal speech going on, what I think is going on is to explain what you're asking is about that I'm going to take it from the perspective reading something. You read something on a paper, the signal from the paper goes through your eyes, it goes to the back of your brain to your visual cortical regions eventually, and then you now got to interpret that signal in your visual pathway of what you're reading. How are you going to do that in terms of speech? That visual signal then goes to your speech pathway
Starting point is 01:10:21 in the motor cortex in front here in Broca's area, and you silently speak what you read in your brain without moving your muscles. Sometimes, actually, if you put electrodes, EEG, EMG electrodes on your laryngeal muscles, even on birds, you can do this. You'll see activity there while reading or trying to speak silently silently even though no sounds coming out. And so your speech pathway is now speaking what you're reading. Now to finish it off, that signal is sent to your auditory pathway so you can hear what you're speaking in your own head. That's incredible. And this is why it's complicated. Because you're using like three different pathways,
Starting point is 01:11:08 the visual, the speaking motor one in the auditory, to read, oh, and then you got to write. Right? Okay, here comes the fourth one. Now, the hand area's next to your speech pathway is got to take that auditory signal or even the adjacent motor signals for speaking and translate it into a visual signal on paper. So you're using it
Starting point is 01:11:29 at least four brain circuits which includes the speech production and the speech perception pathways to write. Incredible. And finally explains to me why when I so I was weaned teaching undergraduates, graduate students and medical students, and I've observed that when I'm teaching, I have to stop speaking if I'm going to write something on the board. I just have to stop all speaking completely. Right. Turns out this is an advantage to catch, because it allows me to catch my voice.
Starting point is 01:12:00 It allows me to slow down a bit, you bit, breathe and inhale some oxygen and so on because I tend to speak quickly if I'm not writing something out. So there's a break in the circuitry for me, or at least they are distinct enough that I have to stop and then write something. Yes, that does imply competing brain circuits for your conscious attention. We have colleagues up at Columbia, Med who are known at least in our circles for voice dictating their papers, not writing them out,
Starting point is 01:12:32 but just speaking into a voice recorder. I've written papers that way. It doesn't feel quite as natural for me as writing things out, but not because I can go quickly from thought to language to typing. I type reasonably not because I can go quickly from thought to language to typing. I type reasonably fast.
Starting point is 01:12:47 I can touch type now. I don't think I ever taught myself. I never took a touch type, of course. I just sort of happen now. My motor system seems to know where the keys are, with enough accuracy that it works. This is remarkable to me that any of us can do this. But when it comes to writing, what I've found is that if my rate of thought and my rate of writing are aligned nicely, things go well. However, if I'm thinking much faster than I can write, that's a problem.
Starting point is 01:13:22 And certainly, if I'm thinking more slowly than I want to write, that's also a problem. And the solution for me has been to write with a pen. I'm in love with these, and I have no relationship to the company, at least not now, although if they want to come, if they want to work with us, I love these pilot V5V7s because not necessarily because of the ink or the feel, although I like that as well, but because of the rate that allows me to write I like that as well, but because of the rate
Starting point is 01:13:45 that allows me to write. They write very well slowly and they write very well quickly. And so I've have this theory supported only by my own annic data, no pure reviewed study, that writing by hand is fundamentally different than typing out information. Is there any evidence that this motor pathway for writing is better or somehow different than the motor pathway for typing? Yeah, that's interesting. I don't know of any studies. I have my own personal experience as well, but trying to put this into the context, if I had to design and experiment to test the hypothesis here, to explain your experience in mind, is that writing by hand, I would argue requires a different set of less skills
Starting point is 01:14:41 with the fingers than typing. So you have to coordinate your fingers more in opposite directions and so forth with typing, but also writing by hand requires more arm movement. And so therefore, I would argue that the difficulty there could be in the types of muscles and the fine motor control you need of those muscles along with speaking in your brain at the same time. So basically I'm a course, I'm a brute.
Starting point is 01:15:13 And so it makes sense that I would have a more primitive writing device would work. That's right, yes. But let me add to this in terms of the, my own personal experience, right? What I find is I can write something faster by hand for a short period of time compared to typing. And that is because I think I run out of the energy
Starting point is 01:15:37 in my arm movements faster than I run out of muscle energy in my finger movements. And I think it takes a longer time for us to write words without fingers, because in terms of the speech. I think you're writing, whether it's by hand or typing, and your speech, they only will align very well if you can type as fast as you can speak, or write as fast as you can speak in your head. I love it. So what you've done, if I understand correctly, is created a bridge between thought and
Starting point is 01:16:11 writing and that bridge is speech. That bridge is speech. That's right. That's right. When you're writing something out, you're speaking it to yourself. And if you're speaking faster than you can type, you got a problem. You see, I do a number of podcast episodes that are not with guest but solo episodes. And as listeners know, these are very long episodes, often two or more hours. And we joke around the podcast studio that I will get locked into a mode of speech where some of it is more elaborative and anecdotal. And then I'll punch out simple declarative sentences. I find it very hard to switch from one module to the next. The thing that I have done in order to
Starting point is 01:16:54 make that transition more fluid and prep for those podcast episodes is actually to read the lyrics of songs and to sing them in my head as a way of warming up my vocal cords, but luckily for those around me, when I do that, I'm not actually singing out loud. And so what you're telling me supports this idea that even when we are imagining singing or writing in our mind, we are exercising our vocal chords. You're actually getting little low potentials of electrical currents reaching your muscles
Starting point is 01:17:31 there, which also means you're exercising your speech brain circuits too without actually going with the full volume activity in the muscles. Incredible. And this idea of singing helps you as well, even with Parkinson's patients and so forth, when they want to say something, singing or listening to music helps them move better. And the idea there is that the brain circuits for singing, or let's say the function of the brain circuits for speech,
Starting point is 01:17:57 being used for singing first is the more ancestral train. And that's why it's easier to do things with singing sometimes, and it is with speaking. I love it. Stutter is a particularly interesting case. And one that every once in a while, I'll get questions about this from our audience. Stutter is complicated in a number of ways, but culturally, in my understanding from these emails that I receive, is that stutter can often cause people to hide and speak less because it can be embarrassing.
Starting point is 01:18:31 And we're, we are often not patient with, with stutter. We also have the assumption that if somebody's stuttering, that they're thinking is slow, but it turns out there are many examples historically of people who could not speak well, but who were brilliant thinkers. I don't know how well they could write, but they found other modes of communication. I realize that you're not a speech pathologist or therapist, but what is the current neurobiological understanding of stutter and are what's being developed in terms of treatments for stutter? Yeah, so we actually accidentally came across stuttering in somberds, and we've published several papers on this. So try to figure out the neurobiological basis.
Starting point is 01:19:14 The first study we had was a brain area called the basal ganglia, the stryanum part of the basal ganglia, involved in coordinating movements, learning how to make movements. When it was damaged in a speech like pathway in these birds, what we found is that they started to stutter as the brain region recovered. And unlike humans, they actually recovered after three or four months.
Starting point is 01:19:43 And why is that the case? Because bird brains undergoes new neurogenesis in a way that human or mammal brains don't. And it was the new neurons that were coming in into the circuit, but not quite, you know, with the right proper activity was resulting in this stuttering in these birds. And after it was repaired, not exactly the old song came back as after the repair, but still it recovered a lot better.
Starting point is 01:20:11 And it's now known, they call this neurogenics stuttering in humans, would damage to the brazil ganglia or some type of disruption to the basal ganglia at a young age also causes stuttering in humans. And even those who are born with stuttering, it's often the basal ganglia that's disrupted in some other brain circuit. And we think the speech part of the basal ganglia. Can adults who maintain a stutter from childhood repair that stutter? They can repair it with therapy, with learning how to speak slower,
Starting point is 01:20:48 learning how to tap out a rhythm during a set. And yeah, I'm not a speech pathologist, but I started reading this literature, and talking to others that, you know, colleagues who actually study stuttering. So yes, there are ways to overcome the stuttering through, you know through behavioral therapy. And I think all of the tools out there have something to do with sensory motor integration.
Starting point is 01:21:17 Controlling with you here with what you output in a thoughtful controlled way helps reduce the stter. There are a couple examples from real life that I wanna touch on and one is somewhat facetious, but now I realize is a serious neurobiological issue, serious meaning I think interesting, which is that every once in a while, I will have a conversation with somebody
Starting point is 01:21:42 who says the last word of the sentence along with me. And it seems annoying in some instances, but I'm guessing this is just a breakthrough of the motor pattern that they're hearing what I'm saying very well. So I'm going to interpret this it kindly and think they're hearing what I'm saying. They're literally hearing it in their mind. And they're getting that low level electrical activity to their throat, and they're just joining me in the in the enunciation of what I'm saying, probably without realizing it.
Starting point is 01:22:13 Can we assume that that might be the case? Well, I wouldn't be surprised so that, you know, the motor theory of speech perception where this idea originally came, what you hear, is going through your speech circuit, and then also activating those muscles slightly. where this idea originally came, which you hear, is going through your speech circuit, and then also activating those muscles slightly. So yes.
Starting point is 01:22:30 So one might argue, okay, is that speech circuit now interpreting what that person is speaking now you're listening to me, and is going to finish it off because it's already going through their brain, and they can predict it. That would be one theory. I don't think they've verdict out there as known, but that's one. The other is synchronizing, turn-taking in the conversation, where you're acknowledging that we understand each other by finishing off what I say. It's almost like a social bonding kind of thing.
Starting point is 01:23:07 The other could be, I want the person to shut out so I can speak as well and take that turn. And each pair of people have a rhythm to their conversation. And if you have somebody who's overtokative versus under-talkative of vice versa, that rhythm can be lost in them finishing ideas and going back and forth.
Starting point is 01:23:26 But I think having something to do with turn taking as well makes a lot of sense. I have a colleague at Stanford who says that interruption is a sign of interest. I'm not sure that everyone agrees. I think it's highly contextual. But there is this form of a verbal nod, I was saying, or things of that sort.
Starting point is 01:23:45 And there are many of these. And I'm often told by my audience that I interrupt my guests and things of that sort. Oftentimes I'll just get caught in the natural flow of the conversation. Right. But I think we've had pretty good turn taking here, I hope, that's so far so good.
Starting point is 01:24:00 I feel glad you feel that way, because especially in the context of a discussion about language. Yes. This seems important. Texting is a very, very interesting evolution of language because what you've told us is that we have a thought it's translated into language. It might not be complete sentences, but texting, I have to imagine this is the first time in human evolution where we've written with our thumbs.
Starting point is 01:24:27 So I don't know, you know, it seems more primitive to me than typing with fingers or hands, but hey, who might have judged the evolution of our species in one direction or the other? But the shorthand, grammatically, often grammatically deficient, incomplete sentence form of texting is an incredible, often grammatically deficient, incomplete sentence form of texting, is an incredible thing to see.
Starting point is 01:24:48 Early in relationships, romantic relationships, people often evaluate the others' text and their ability to use proper grammar and spelling, et cetera. This often quickly degrades, and there's an acceptance that we're just trying to communicate through shorthand. Almost military likes shorthand, but with internally consistent between people, but there's no general consensus of what things mean. But WTFs and OMGs and all sorts of things.
Starting point is 01:25:18 I wonder sometimes whether or not we are getting less proficient at speech because we are not required to write and think in complete sentences. I'm not being judgmental here. I see this in my colleagues, I see this in myself. This is not a judgment of the younger generation. I also know that slang has existed for decades, if not hundreds of years. But I also know that I don't speak the same way
Starting point is 01:25:47 that I did when I was a teenager because I've suppressed a lot of that slang, not because it's inappropriate or offensive, although some of it was, frankly, but because it's out of context. So what do you think's happening to language? Are we getting better at speaking, worse at speaking, and what do you think the happening to language? Are we getting better at speaking, worse at speaking,
Starting point is 01:26:05 and what do you think the role of things like texting and tweeting and shorthand communication, hashtagging, what's that doing to the way that our brains work? Yeah, I think that a one in terms of, you know, measuring your level of sophistication intelligence and you say, OMG, right? I think that also could be a cultural thing
Starting point is 01:26:28 that you belong to the next generation, or you're being cool, if you're an older person using OMG and other things that the younger generation would use. But really think about it clearly, texting actually has allowed for more rapid communication amongst people. I think without the invention of the phone before then, or texting back and forth, you had to wait days
Starting point is 01:27:00 for a letter to show up. You couldn't call somebody in the phone and talk as well, you know, and so this rapid communication, in terms of the rapid communication of writing in this case. So I think actually it's more like a use it or lose it kind of a thing with the brain. The more you use a particular brain region or circuit, the more enhanced, it's like a muscle. The more you exercise it, the more healthier it is, the bigger it becomes, and the more space it takes, and the more you lose something else. So, I think taxing is not decreasing the speech prowess, so the intellectual prowess of speech, it's converting it and using it a lot in a different way.
Starting point is 01:27:48 In a way that may not be as rich in regular writing because you can only communicate so much nuance in short term writing, but whatever that, whatever is being done, you got people texting hours and hours and hours and hours on the phone. So whatever your thumb circuit is gonna get pretty big, actually.
Starting point is 01:28:10 I do wonder whether, many people have lost their jobs based on tweets. The short latency between thought and action and distribution of one's thoughts is incredible. Yes. And I'm not just talking about people who apparently would have poor prefrontal top-down control. This is geek speak, by the way, for people that lack impulse control. But high-level academics, I'm not going to point fingers at anyone,
Starting point is 01:28:39 but examples of where you see these tweets, what were they thinking? Yep. So presumably there's an optimal strategy between the thought speech motor pathway, especially when the motor pathway engages communication with hundreds of thousands of people and retweets in particular and the cut and paste function and the screenshot function are often the reason why speech propagates. Yep. So to me, it's a little eerie that just that the neural circuitry can do this and that
Starting point is 01:29:14 we are catching up a little bit more slowly to the technology and you've got these casualties of that mismatch. I think that's a good adjective to use, the casualties, what's going on. Because yes, it is the case with texting, what you're really losing there is not less so the ability to write, but more of the ability to interpret what is being written.
Starting point is 01:29:41 And you can over-under-terpet something that somebody means. On the flip side of that, you know, when if somebody is writing something very quick, they could be writing instinctually, more instinctually, their true meaning. And they don't have time to modify and color code what they're trying to say. And that's what they really feel, and as opposed to saying a more nuanced way. So I think both sides of that casualty are present,
Starting point is 01:30:14 and that's a downturn, you know, unintended negative consequence of short term, I mean short word communications. Yeah, I agree that this whole phenomenon could be netting people that normally would only say these things out loud once inside the door of their own home or not at all. Right. It's an interesting time that we're in. These of you speech and language and motor patterns.
Starting point is 01:30:39 It's a part of the human evolution for language. I think this is all part of our evolution. That's right. So for those of you thinking terrible thoughts, please put them in the world and be a casualty. And for those of you that are not, please be very careful with how proficient your thought to language to motor action goes. Maybe the technology companies should install some buffers, some AI-based buffers. Right, that's taking some EEG signals from your brain while you're texting to say, okay, this is not a great thought, slow down. Right, this doesn't reflect your best state.
Starting point is 01:31:13 Yeah. That brings me to what was going to be the next question anyway, which is we are quickly moving toward a time where there will be an even faster transition from thought to speech to motor output. And maybe won't require motor output, what I'm referring to here is some of the incredible work of our colleagues Eddie Chang at UCSF and others who are taking paralyzed human beings and learning to translate the electrical signals of neurons in various areas, including speech
Starting point is 01:31:43 and language areas, to computer screens that type out What these people are thinking in other words paralyze people can put their thoughts on in into writing That's a pretty extreme and wonderful example of recovery of function That is sure to continue to evolve But I think we are headed toward a time not too long from now where My thoughts can be translated into words on a page if I allow that to happen. Yeah, so, and Eddie Chang's work, which I admire quite a bit in sight in my papers, I think
Starting point is 01:32:16 he's really one of those at the leading edge of trying to understand within humans the neurovileiralgia speech. He may not say it directly, but I talked to him about this. It supports this idea that the speech circuit in a separate language module, I don't really think that there's a separation there. So with that knowledge, yes, and putting electrodes in the human brain,
Starting point is 01:32:40 and then translating those electrical signals to speech currents, yeah, we can start to tell what is that person thinking? Why? Because we often think in terms of speech. And without saying words. And that's a scary thought. And now imagine if you can now translate those into a signal that transmits something wirelessly,
Starting point is 01:33:01 and someone from some distant part of the planet is hearing your speech from a wireless signal without you speaking. So, probably that won't be done in an ethical way. Who knows? I mean, the ethics of doing that probably might not happen, but who knows? We have these songbirds. We apply the same technique to them.
Starting point is 01:33:24 We can start to hear what they're singing in their dreams or whatever, even though they don't produce sound. So we can find out by testing on them. It's coming. One way or another, it's coming. For those listening who are interested in getting better at speaking and understanding languages, are there any tools that you recommend? And here again, I realize you're not a speech therapist,
Starting point is 01:33:47 but here I'm not thinking about emeliorating any kind of speech deficiency. I'm thinking, for instance, do you recommend that people read different types of writing? Would you recommend that people learn how to dance in order to become better at expressing themselves verbally? And feel free to have some degrees of freedom in this answer. These are obviously not peer-reviewed studies that we're referring to, although there may
Starting point is 01:34:15 be. But I'm struck by the number of things that you do exceedingly well, and I can't help but ask, well, the singing, which I realize it may, your brother didn't pay me to say this, may not be quite as good as your brother's yet, but you'll surpass him, I'm guessing at some point. Getting there. Getting there.
Starting point is 01:34:35 Exactly. There you go. You know, should kids learn how to dance and read hard books and simple books, what do you recommend should adults learn how to do that? Everyone wants to know how to keep their brain working better, so to speak, but also I think people want to be able to speak well,
Starting point is 01:34:53 and people want to be able to understand well. Yeah, so what I've discovered personally, right, is that so when I switch from pursuing a career in science from a career in science from a career in dance, I thought one day I would stop dancing, but I haven't because I find it fulfilling for me, just as a life experience.
Starting point is 01:35:18 So ever since I started college, my late teens in early 20s, I kept dancing even till this day. And they've been periods of time like during the pandemic, where I slowed down on dancing and so forth. And when you do that, you realize, okay, they're part of your body, where your muscle tone
Starting point is 01:35:38 decreases a little bit in somewhat or you could start to gain weight. I somehow don't gain weight that easily. And I think it's related to my dance, if that's meaningful to your audience. But what I found is, you know, in science, we'd like to think of a separation between movement and action and cognition.
Starting point is 01:35:57 And there is a separation between perception and production, cognition being perception, production being moving, right? But if the speech pathways is next to the movement pathways, what I discover is by dancing, it is helping me think. It is helping keeping my brain fresh. It's not just moving my muscles. I'm using the circuitry in my brain to control a whole big body. You need a lot of brain tissue to do that. And so I argue if you want to stay cognitively intact into your old age, you better be moving. And you better be doing it consistently,
Starting point is 01:36:37 whether it's dancing, walking, running, and also practicing speech, oratory speech, and so forth, or singing is controlling the brain circuits that are moving your facial musculature, and it's going to keep your cognitive circuits also in tune. And I'm convinced of that for my own personal experience. For me, long slow runs are a wonderful way to kind of loosen the joints for long podcasts, especially the solo podcasts, which can take many hours to record. And without those long slow runs, at least the day before or even the morning of, I don't
Starting point is 01:37:15 think I could do it, at least not as well. All right, well, you're experiencing something similar, so that's an NF2. Yeah, NF2. I'm tempted to learn how to dance because there are a lot of reasons to learn how to dance. People can use their imagination. I definitely want to get the opportunity to talk about some of the newer work that you're into right now about genomes of animals.
Starting point is 01:37:40 As you perhaps can tell from my quite authentic facial expressions, I adore the animal kingdom. I just find it amazing, and it's the reason I went into neurobiology, in part. So many animals, so many different patterns of movement, so many body plans, so many specializations. What is the value of learning the genomes of all these animals? I can think of conservation based, you know, schemes of trying to preserve these precious critters.
Starting point is 01:38:11 But what are you doing with the genomes of these animals? What do you want to understand about their brain circuits? And how does this relate to some of the discussion we've been having up in? Yeah, I've gotten very heavily involved in genomes. You know, not just to get at an individual gene involved in the trade of interest, like spoken language, but I realize that nature has done natural experiments for us. But all these species out there with these various traits, and the one that I'm
Starting point is 01:38:41 studying like vocal learning, has evolved multiple times among the animal kingdom, even if it's rare, it's multiple times. And the similar genetic changes occurred in those species. But to find out what those genetic changes that are associated with the trait of interest and not some other trait like flying in birds as opposed to singing, you have to do what's called comparative genomics, even in the context of studying the brain. And you need their genomes to compare the genomes and do like a GWAS, a genome-wide association study, not just within a species
Starting point is 01:39:17 like humans, but across species. And so you need a good genomes to do that. Plus, I've discovered I'm also interested in evolution in origins. How did these species come about a similar trait in the last 300 million years or 60 million years, depending on who you're talking about? And you need a good phylogenetic tree to do that. And to get a good phylogenetic tree, you also need their genomes.
Starting point is 01:39:44 And so because of this, I got involved in large-scale consortiums to produce genomes of many different species, including my vocal learners and my, their closest relatives that I'm fans of. But I couldn't convince the funding agencies to give me the money to do that just for my own project. But when you get a whole bunch of people together
Starting point is 01:40:04 who want to study various traits, you know, heart disease or what or loss and gain a flight and so forth, suddenly we all need lots of genomes to do this. And so now that got me into a project to lead something called a vertebra genomes project to eventually sequence all 70,000 species on the planet. And Earth bio genome project, all new chaotic species, all 2 million of them.
Starting point is 01:40:32 And to no longer be in a situation where I wish I had this genome, now we have the genetic code of all life on the planet, create a database of all their traits, and find the genetic association with everything out there that makes a difference from one species to another. One more piece of the equation to add to this story is what I didn't realize as a neuroscientist were that these genomes are not only incomplete, but they have lots of errors in them. False gene duplications where mother and father chromosomes
Starting point is 01:41:11 were so different from each other that the genome algorithm, assembly algorithms, treated them as two different genes in this part of the chromosome. So there are a lot of these false duplicated genes that people were thought were real but were not. Or missing parts of the genome because the enzymes used to sequence the DNA couldn't get through this regulatory region that folded up on itself and made it hard to sequence.
Starting point is 01:41:38 And so I end up in these consortiums pulling in the genome sequencing companies developing the technology to work with us to improve it further. And the computer science guys who then take that data and that technology and try to make the complete genomes and make the algorithms better to produce what we now just did recently and led by an effort by Adam Philippi is is the first human telomerotelomer genome with no errors, all complete, no missing sequence. And now we're trying to do the same thing with vertebrates and other species.
Starting point is 01:42:14 Actually, we improved that, but even before we got to what we call telomerotelomer, from one end of the chromosome to another. And what we're discovering is in this dark matter of the genome that was missing before turns out to be some regulatory regions that are specialized in vocal learning species and we think are involved in developing speed circuits. Incredible.
Starting point is 01:42:36 Well, so much to learn and that we're going to learn from this information. Early on in these genome projects and connect-home projects, I confess I was a little bit cynical. This would be about 10, 15 years ago. I thought, okay, necessary, but not sufficient for anything. We need it, but it's not clear what's gonna happen, but you just gave a very clear example of what we stand to learn from this kind of information. And I know from the conservation side,
Starting point is 01:43:01 there's a huge interest in this, because even though we would prefer to keep all these species alive rather than clone them, they're these sorts of projects do offer the possibility of potentially recreating species that were lost due to our own ignorance or missteps or what have you. Yes. And along those lines, because we got involved in genomics, some of the first species that we start working on are critically endangered species.
Starting point is 01:43:30 And I'm doing that not only for perspective, so understanding their brains and the genes involved in their brain function, but I feel like it's a moral duty. So the fact that now I become more involved in genome biology and have helped develop these tools for more complete genomes, let's capture their genetic code now before they're gone. And could we use that information to resurrect the species at some future time, if not in my lifetime, in the future and generations ahead of us. And so, in anticipation of that, we created a database we call the genome arc, and no pun intended, like Noah's arc,
Starting point is 01:44:15 meant to store the genetic code as complete genome assemblies as possible for all species on the planet to be used for basic signs, but also some point in the future. And because of that, funding agencies or private foundations that are insurgent in conservation have been reaching out to me now, a neuroscientist, to help them out in producing high-quality genome data of endangered species that they can use like revive and restore
Starting point is 01:44:43 who want to resurrect the passenger pigeon or colossal who wants to resurrect the woolly mammoth. And so we're producing high quality genomes for these groups for the conservation projects. What a terrific and important initiative. And I think for those listening today, they now certainly understand the value of deeply understanding the brain structures and genomes of different
Starting point is 01:45:06 species, because I confess even though I knew a bit of the songbird literature and I certainly understand that humans have speech and language, I had no idea that there was so much convergence of function, structure, and genomes. And to me, you know, I feel a lot more like an ape than I do a songbird. Right. And yet here we are with the understanding that there's a lot more similarity between songbirds and humans than I certainly ever thought before. Yeah. Something very close to home for us humans, I can give you an example of, is evolution
Starting point is 01:45:39 of skin color. In skin color, we use it, unfortunately, for racism and so forth. We use it also for good things, so let in more light or let out less light, depending on the part of the planet, our population evolved in. And most people think dark skin people all evolve in the same dark skin person and light skin people all evolve in the same light skin person, but that's not the case. Dark skin and light skin amongst humans has evolved independently in the multiple times, like in the Pacific Islands versus Africa.
Starting point is 01:46:13 It's just depending on the angle of light hitting the earth as to whether you need more protection from the sun or less protection that's also associated with vitamin D synthesis in the skin. And so, and each time where darker or lighter skin evolved independently, it hit the same gene. You know, the melatonin. Melonin. Melonin receptor, that's right, yes. Yeah.
Starting point is 01:46:43 Genes that are involved in melanin formation. And so those genes evolve some of the same mutations, even in different species. It's not just humans. In equatorial regions, they're darker skinned animals than going away from the equator. All right, I think of arctic foxes. That's right, polar bears. And so some of the same genes are used in an evolutionary perspective to evolve in a similar way within and across species. Incredible. And that's the same thing happening in a brain too. Language is no exception.
Starting point is 01:47:19 Well, I have to say, somebody who is a career neuroscientist, but as I mentioned several times, who also adores the animal kingdom, but is also obsessed with speech and language, and at a distance, not as a practitioner of music and dance. This has been an incredible conversation and opportunity for me to learn. I know I speak for a tremendous number of people
Starting point is 01:47:44 when I just really want to say thank you for joining us today. You are incredibly busy. It's clear from your description of your science and your knowledge base that you are involved in a huge number of things. Very busy. So thank you for taking the time to speak to all of us. Thank you for the work that you're doing,
Starting point is 01:48:01 both on speech and language, but also this important work on genomes and conservation of endangered species and far more. And I have to say, if you would agree to come back and speak to us again sometime, I'm certain that if we were to sit down even six months or a year from now, there's going to be a lot more to come. Yeah, we have some things cooking. And thank you for inviting me here to get the word out to the community of what's going on in the science world. Well, we're honored and very grateful to Eric.
Starting point is 01:48:30 Thank you. Welcome. Thank you for joining me today for my discussion with Dr. Eric Jarvis. If you'd like to learn more about his laboratory's work, you can go to Jarvis Lab, spell J-A-R-V-I-S lab, all one word, Jarvislab.net. And there you can learn about all the various studies taking place in his laboratory, as
Starting point is 01:48:48 well as some of the larger overarching themes that are driving those studies, including studies on human genomics and animal genomics, that surely are going to lead to the next stage discoveries of how we learn and think about and indeed use language. If you're learning from Ender and join this podcast, please subscribe to our YouTube channel. That's a simple zero-cost way to support us. Please also subscribe to the podcast on Spotify and Apple and on both Spotify and Apple,
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Starting point is 01:51:20 And last, but certainly not least, thank you for your interest in science. And last but certainly not least, thank you for your interest in science.

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