Speaker 1: How can we understand what music is about from the
Speaker 1: point of view of neuroscience. Can music be leveraged to
Speaker 1: help with anxiety disorders, or with dementia or with Parkinson's disease?
Speaker 1: Is music universal or does it have to do with
Speaker 1: what you have absorbed in your lifetime? How is music
Speaker 1: like a language but one with very particular structure and
Speaker 1: therefore high predictability. And what does this have to do
Speaker 1: with Stevie Wonder on the High Hat or the relationship
Speaker 1: between music and color. Welcome to Inner Cosmos with me
Speaker 1: David Eagleman. I'm a neuroscientist and an author at Stanford
Speaker 1: and in these episodes we sail deeply into our three
Speaker 1: pound universe to understand why and how our lives look
Speaker 1: the way they do. Today's episode is about music and
Speaker 1: the brain, and this is a topic that has been
Speaker 1: requested by several different listeners, so I prioritized making this episode. Music.
Speaker 1: I suspect is a popular topic because music can be
Speaker 1: so emotive for us and so catchy and so meaningful.
Speaker 1: My father, for example, who was the quintessential tough guy
Speaker 1: when he would listen to Mozart or Brahms or Beethoven,
Speaker 1: he would have tears streaming down his cheeks. And as
Speaker 1: a child, I didn't have much understanding of classical music,
Speaker 1: but that really caused me to wonder, what is going
Speaker 1: on here? Why does this music wafting out of the
Speaker 1: radio evoke such strong emotions and perhaps such deep memories
Speaker 1: in my father? And as I got older and became
Speaker 1: a neuroscientist, I wondered, is there something you unique in
Speaker 1: the structure of the human brain that ties music so
Speaker 1: closely with our emotional experiences? So I decided to do
Speaker 1: an episode on this today, and I realized there was
Speaker 1: no one better to ring up than my friend and colleague,
Speaker 1: Daniel Leviton. He's the founding Dean of Arts and Humanities
Speaker 1: at Minerva University in San Francisco and a professor emeritus
Speaker 1: of psychology and neuroscience at McGill University in Montreal. You
Speaker 1: may know Dan because he wrote a book called This
Speaker 1: Is Your Brain on music, the Science of a Human Obsession,
Speaker 1: which became a big New York Times bestseller, and he's
Speaker 1: also written four other best selling books, including his latest,
Speaker 1: which is called I Heard There Was a Secret Chord.
Speaker 1: Music as Medicine. Now, as you may suspect. Dan is
Speaker 1: also a very talented musician. He composes music and he's
Speaker 1: worked on albums by Blue Oyster Cult and Chris Isaac
Speaker 1: and Joe Satriani, among many others. He does this as
Speaker 1: an advisory producer a recording engineer. So given his expertise,
Speaker 1: I wanted to sit down with Dan to get his
Speaker 1: take on music and the brain. Okay, Dan, what goes
Speaker 1: on in the brain when you listen to music?
Speaker 2: Yeah, well, it really is quite fascinating. So it begins
Speaker 2: with the sound waves impinging on your ear drums. They
Speaker 2: wiggle in and out, and all the information you have
Speaker 2: about the auditory world comes from molecules vibrating in some medium,
Speaker 2: in our case air, it could be underwater, and then
Speaker 2: your ear drums just wiggle in and out, and then
Speaker 2: your brain has to take that wiggling in and out
Speaker 2: and extract from it all the different sounds a bird chirping,
Speaker 2: a leaf blower going, the oboe in the symphony as
Speaker 2: opposed to the French horns in a crowded room, the
Speaker 2: conversation you're trying to listen to in front of you,
Speaker 2: as well as that when you're eavesdropping in. It has
Speaker 2: to separate all that out. And the way it does
Speaker 2: that is that your brain has special processing circuits. I
Speaker 2: was going to use the word designed, but of course
Speaker 2: they weren't designed, but evolved to do different distinct functions.
Speaker 2: One circuit processes the loudness is anything louder, is it
Speaker 2: getting softer? And it follows that loudness trajectory, which can
Speaker 2: be an important cue as.
Speaker 3: To what's going on. Pitch duration.
Speaker 2: The pitches get in a separate circuit, bound into a
Speaker 2: representation of melody and harmony, the durations into a representation
Speaker 2: of rhythm and meter, the loudness into accent structure, timbre,
Speaker 2: which is the quality that distinguishes your voice from my
Speaker 2: voice when we're saying the same thing, or a trumpet
Speaker 2: from a piano when they're playing the same note. That's
Speaker 2: a combination of spectral temporal information, in other words, pitch
Speaker 2: and time and loudness. It all comes together later in
Speaker 2: the brain and you just hear that song where later
Speaker 2: in the brain is maybe forty milliseconds. It happens so
Speaker 2: seamlessly that it just sounds like we're hearing the song,
Speaker 2: but we're not. Our brain is hearing the pitch, the rhythm,
Speaker 2: the loudness, the timber, and our evidence, David, that this
Speaker 2: happens is not just from neuroimaging, but from patients. We
Speaker 2: see patients with focal brain damage who suddenly lose their
Speaker 2: perception of pitch, but they retain rhythm or vice versa.
Speaker 1: Okay, so it's this terrifically complicated computational process. So why
Speaker 1: does it end up feeling so emotional for us?
Speaker 3: Well?
Speaker 2: So I think there are both neurobiological reasons and evolutionary
Speaker 2: reasons that are connected. Of course, the simple answer is
Speaker 2: it's emotional for us because emotion circuits in the brain
Speaker 2: are involved in music processing. And by that I mean,
Speaker 2: among others, the well known reward center that you and
Speaker 2: I have talked about in our own classes over the
Speaker 2: years and with one another, the limbic system, the structures
Speaker 2: like the nucleus of Cumban's, the amygdala, the ventral tegmental area.
Speaker 2: This is the emotional core part of the reptilian brain
Speaker 2: that you know motivates us to move out of the
Speaker 2: way of some approaching danger or to signal pleasure when
Speaker 2: we're hungry and we finally get a taste of something sweet.
Speaker 2: Music activates that same center, and in fact, it was
Speaker 2: my lab that was the first to show that our
Speaker 2: brain produces dopamine in response to music listening, and later
Speaker 2: we showed that our brain produces its own endogenous opioids
Speaker 2: in response to music listening, all part of that well
Speaker 2: known pleasure network. Now, of course, that raises the question
Speaker 2: why why is you know, over ever solutionary timescals did
Speaker 2: music hit that emotional center and hear The answer is
Speaker 2: by fer Kate. One is that the well known startle response.
Speaker 2: You hear a sudden, loud noise and you jump. That's
Speaker 2: evolutionarily adaptive because you know, you know, even lizards, snakes,
Speaker 2: reptiles have to move out of the way of something
Speaker 2: that might step on them or smash them. And that
Speaker 2: startle response in humans goes directly from the inner ear
Speaker 2: to the cerebellum and the brain stem. Before we even
Speaker 2: figure out what the sound is, we startle and that's
Speaker 2: connected to emotion centers. And so music, because it's an
Speaker 2: auditory stimulus, is hardwired to movement and to emotion.
Speaker 1: So what happens in the brain when you play an instrument.
Speaker 2: Playing instrument is one of the most neuroprotective things we
Speaker 2: can do. Glistening activates every area of the brain that
Speaker 2: we so far mapped, as does playing an instrument. But
Speaker 2: the added advantage of playing an instrument is that it's
Speaker 2: active rather than passive, and it involves prediction centers in
Speaker 2: the prefrontal cortex, particularly broad An area forty seven, which
Speaker 2: is a pattern detector. You know, Venode, Menna and I
Speaker 2: at Stanford for thirty years have been looking at this
Speaker 2: little sliver of tissue on either side of your between
Speaker 2: your top of your ears and your eyeballs broad and
Speaker 2: forty seven, and Michael Patritus and I at mcgil have
Speaker 2: also looked at it as that part of the human
Speaker 2: brain that primates lack that allows us to process temporal patterns,
Speaker 2: either in vision, touch or sound. And so in playing
Speaker 2: an instrument, you've got to plan what you want it
Speaker 2: to sound like. Hopefully you've got some idea of what
Speaker 2: you want to come out, and then you've got to
Speaker 2: use a feedback loop to listen to what came out
Speaker 2: and see how well it matches with what you intended
Speaker 2: and that adjust or not. And Broaden forty seven is
Speaker 2: a part of that, as well as other prefrontal areas
Speaker 2: and temporal areas.
Speaker 1: Before we move on some other questions, I want to
Speaker 1: ask what got you into this intersection between music and
Speaker 1: the brain.
Speaker 3: It wasn't intentional.
Speaker 2: I had dropped out of college after my sophomore year
Speaker 2: to play in a series of bands, and that led
Speaker 2: to me becoming a staff producer at Columbia Records in
Speaker 2: the eighties and in the nineties, when the music business
Speaker 2: seemed to be imploding, a bunch of us who had
Speaker 2: entered the business around the same time, figured we needed
Speaker 2: a plan B, that this may not be a sustainable career,
Speaker 2: and so I went back and finished my bachelor's degree
Speaker 2: at Stanford. I just worked in every lab that would
Speaker 2: have me. Then I went to graduate school and Oregon
Speaker 2: in order to work with Doug Hintsman and Helen Neville
Speaker 2: a language specialist, and of course Mike Posner on neuroimaging.
Speaker 2: And I was just doing all these things in parallel
Speaker 2: and loving it. I mentioned all these names because they
Speaker 2: were very important mentors to me, each of them. And
Speaker 2: in the third year of my graduate program, Posner, who
Speaker 2: was my principal advisor, said, you know you're gonna have
Speaker 2: to specialize. What do you want to do when you
Speaker 2: grow up. I said, well, I really love all of this.
Speaker 2: I love psycholinguistics, I love memory, I love decision making,
Speaker 2: and I had worked in all those areas. And he said, well,
Speaker 2: you know, you have this background as a musician, and
Speaker 2: there's a lot of competition for jobs in those other fields.
Speaker 2: There's this emerging field of psychology of music with a
Speaker 2: handful of people in it. Maybe if you go into
Speaker 2: that field, there'll be a lot of low hanging fruit,
Speaker 2: as it were, a lot of studies that have obviously
Speaker 2: need to be done that haven't been done yet. And
Speaker 2: in addition, although nobody's going to advertise for a music
Speaker 2: psychology faculty member, all those other things apply to music psychology,
Speaker 2: decision making, how do we decide what we want to
Speaker 2: listen to? Cyclel linguistics, psychology of lyrics and music, individual
Speaker 2: differences in musical taste, memory for music. So it was
Speaker 2: Mike who said preciently that I should brand myself as
Speaker 2: a music psychologist. Of course, back in those days, there
Speaker 2: were no neuroscience departments, there were no neuroscience programs. You
Speaker 2: could not study neuroscience as you and I know it.
Speaker 2: And I'll make a distinction for our listeners between like
Speaker 2: molecular neuroscience, which was done in biology departments where you
Speaker 2: only look at a single neuron and you've never even
Speaker 2: considered what a thought might be and what we call you.
Speaker 2: And I work in the area systems neuroscience, where we're
Speaker 2: looking at the big ideas andions of neurons communicate with
Speaker 2: other millions in neurons.
Speaker 1: I know that you feel like that the music psychology
Speaker 1: world was not particularly good let's say twenty years ago,
Speaker 1: so give us a sense of what it was like
Speaker 1: at that point when people thought about I'm going to
Speaker 1: study the psychology music and what it's like now and
Speaker 1: what's changed.
Speaker 2: And there were a bunch of other people who hadn't
Speaker 2: studied cognitive psychology but fancy themselves music psychologists, and they
Speaker 2: did a bunch of bad studies, the poster child for
Speaker 2: that being the Mozart effect study, which purported to show
Speaker 2: that listening to Mozart for twenty minutes would make you smarter.
Speaker 2: And there have now been literally one hundred studies that
Speaker 2: shows that that was just bullshit. It was a poorly
Speaker 2: controlled study, It was done by people who had no
Speaker 2: experience in human experimental design. They stepped outside their lane,
Speaker 2: and so there was a lot of garbage work being done.
Speaker 2: What's different now is that we've had twenty years of
Speaker 2: people applying to graduate school who knew they wanted to
Speaker 2: study music psychology. Some of them went into music psychologists'
Speaker 2: labs like mine. Others did what I did. They went
Speaker 2: into the lab of a memory person or an attention
Speaker 2: or brain imaging person and just used that interest in
Speaker 2: music to design studies.
Speaker 1: And so what sort of things have come out in
Speaker 1: the last twenty years. Part of this has to do
Speaker 1: with the advent of neuroimaging, right.
Speaker 2: Well, that really, that really is what kicked it off, because,
Speaker 2: as you know, David, the study of emotion was rather unseemly.
Speaker 2: I think it began with the foundation of the first
Speaker 2: psychology labs in the world by Vuntenfeckner in Europe. Of course,
Speaker 2: William James was always more interested in the esthetics and
Speaker 2: artistics side, but it was the behaviorist movement of the
Speaker 2: fifties led by BF Skinner, that if something wasn't deservable
Speaker 2: and replicable, it wasn't worth study. And so emotions just
Speaker 2: seemed too squishy, and music as the language of emotion
Speaker 2: seemed like the squishiest of all. What happened with the
Speaker 2: first studies of neuroimaging, which Mike Posner was part of
Speaker 2: nineteen ninety eight ninety nine. We were able to actually
Speaker 2: see pictures of the brain caught in the act of
Speaker 2: thinking and remembering and imagining, and that gave it a
Speaker 2: biological basis reality. You could replicate brain imaging experiments, and
Speaker 2: so first the study of emotion, and then shortly followed
Speaker 2: by the study of music with the first neu imaging
Speaker 2: studies of music in the early two thousands, that put
Speaker 2: it back on the table as something that was worthy
Speaker 2: of study and could be done in a rigorous fashion.
Speaker 1: So your latest book, I heard, There was a Secret Chord,
Speaker 1: looks at this issue of muse musick as medicine. So
Speaker 1: tell us about that.
Speaker 2: That's something that I think most of us have experienced intuitively, certainly,
Speaker 2: it goes back tens of thousands of years using music
Speaker 2: to treat injury and disease to shamans and faith healers
Speaker 2: and indigenous tribes. And it was really in the last
Speaker 2: ten years. I would say that the idea that music
Speaker 2: had an evidence base for treating injury disease promoting wellness,
Speaker 2: helping with mental disorders like depression, post traumatic stress disorder, anxiety.
Speaker 2: There's been eight thousand papers in the last two years
Speaker 2: alone in peer review journals on medical applications of music,
Speaker 2: and so about five years ago I became involved with
Speaker 2: the National Institutes of Health and the White House Science Office,
Speaker 2: leading various expert panels to figure out what do we
Speaker 2: really know and what do we don't know and what
Speaker 2: remains to be done. That led to a call for proposals.
Speaker 2: The NIH put forty million into music and medicine research
Speaker 2: a few years back. So I looked for a book
Speaker 2: on music and medicine because I wanted to know what
Speaker 2: the state of the art was, and I couldn't find one.
Speaker 2: There were a lot of papers, but no books, and
Speaker 2: so I ended up writing the book I wanted.
Speaker 1: To read and so give us a sense when it
Speaker 1: comes to something like, let's start with dementia, how would
Speaker 1: music be useful in the case of something like Alzheimer's.
Speaker 2: Not all dementia is Alzheimer's, of course, and not all
Speaker 2: memory loss comes from Alzheimer's. But the most straightforward case
Speaker 2: of somebody with profound memory loss, perhaps due to Alzheimer's,
Speaker 2: Corsokov's stroke, whatever. They may not recognize where they are,
Speaker 2: They may not recognize loved ones. They may not even
Speaker 2: recognize themselves in the mirror. This is profoundly We've seen
Speaker 2: patients who will walk by a mirror and think they're
Speaker 2: talking to someone else, and then they get angry because
Speaker 2: the person in the mirror appears to be mocking them
Speaker 2: by gesturing the same way they are, and it causes
Speaker 2: one of two reactions. Individuals either turn in on themselves,
Speaker 2: fold in on unsells because the external world makes no
Speaker 2: sense and they become somewhat catatonic, or they become angry, agitated,
Speaker 2: and violent and in that case have to be medicated.
Speaker 2: They might start beating up on their spouses, not recognizing them.
Speaker 2: Music follows a kind of principle that computer science talks about,
Speaker 2: which is first in, last out.
Speaker 3: This is a holder for the old models of computer memory.
Speaker 2: The first thing that goes into the memory is the
Speaker 2: last thing to come out. And because we've been listening
Speaker 2: to music in the womb most of us and through
Speaker 2: our childhoods, those memories the most deeply embedded in the
Speaker 2: brain and the most resilient and resistant to decay or damage.
Speaker 2: And so if we play music from the youth of
Speaker 2: an Alzheimer's patient, somebody with profound memory loss, play the
Speaker 2: music from say the ages of twelve to fourteen or
Speaker 2: sixteen that's preserved in most cases, and it allows them
Speaker 2: to profoundly reconnect with a part of themselves they had lost.
Speaker 2: It eases them, it comforts them, It triggers memories that
Speaker 2: had been buried, and that kind of therapy or intervention
Speaker 2: can pull them out of the state they're in and
Speaker 2: actually have consequences for days or weeks where they come
Speaker 2: alive again.
Speaker 1: It doesn't cure or help the dementia the cognitive loss exactly,
Speaker 1: but it triggers memories and pulls them back to state
Speaker 1: where they've been. And it can also revivify skills that
Speaker 1: someone has. For example, musicians with profound dementia who get
Speaker 1: an instrument put in their hand and they go and
Speaker 1: play again as though they're young.
Speaker 2: It's really extraordinary. And we saw this play out in
Speaker 2: recent years with Glenn Campbell first and then with Tony Bennett,
Speaker 2: both of whom had profound memory loss and did not
Speaker 2: know where they were. When Glenn did his final tour
Speaker 2: with dementia and in the throes of Alzheimer's. He would
Speaker 2: sometimes play a song two or three times in a
Speaker 2: row because they didn't realize he had just played it,
Speaker 2: or he'd forget what song he was supposed to play.
Speaker 2: But once the notes, the first few notes happened, he
Speaker 2: knew where he was. Say, with Tony Bennett, he could
Speaker 2: sing for an hour and a half without stopping once
Speaker 2: the music took over. These are what we cognitive scientists
Speaker 2: call overlearned. They're not just in memory, but they're in
Speaker 2: memory with thousands and thousands of traces overlaid on top
Speaker 2: of one another and their procedural memory. Once your vocal
Speaker 2: cords and your fingers get going, they kind of take over. Now,
Speaker 2: to be clear, the memory is not in your fingers,
Speaker 2: although it feels that way. If I were to scoop
Speaker 2: your brain outside your head, your fingers would not keep
Speaker 2: playing like a chicken with its head cut off. But
Speaker 2: those pathways are so profoundly deeply embedded that yeah, you
Speaker 2: can keep going even with Alzheimer's, and it gives the
Speaker 2: patient a rare act of competence in a world in
Speaker 2: which they're otherwise incompetent. It gives them agency in the world.
Speaker 2: This can really affect their mood and their quality of
Speaker 2: life and way of being in the world.
Speaker 1: Now, one of the things I've talked about on in
Speaker 1: previous episode is right Bo's law, which is where older
Speaker 1: memories are more secure, they're burned down more deeply than
Speaker 1: newer memories. And of course we see this with people
Speaker 1: with cogno.
Speaker 2: I thought you were going with Bow's law, like the
Speaker 2: bow on a violin, the earliest violin pieces are the
Speaker 2: ones that are the most embedded.
Speaker 1: Yeah, nope, Riebo Ribot, Yeah, which is you know, he
Speaker 1: was the first I think this is actually the first
Speaker 1: rule in neurology, as in the oldest rule.
Speaker 2: Yeah.
Speaker 1: But anyway, he saw that, you know, things from childhood
Speaker 1: were remembered by people with let's say dementia, and things
Speaker 1: they did last week or last month were not remembered,
Speaker 1: so older members more stable. Now, the reason this is
Speaker 1: so strange is because nothing else works that way. Institutions,
Speaker 1: for example, don't remember their older stuff better than they
Speaker 1: remember their newer stuff. But brain works this way.
Speaker 3: That is true.
Speaker 1: So my question is, I mean, when when it comes
Speaker 1: to music, presumably most of these great musicians have been
Speaker 1: playing since they were a little kids, and these particular
Speaker 1: songs are overlearned, as you mentioned. Is this an expression
Speaker 1: of simply of Ribo's law, which is that it's an
Speaker 1: older memory and that's why they're able to do it?
Speaker 1: Or is there something different about music than if I
Speaker 1: ask them something about their you know, their their childhood home.
Speaker 3: What a great question.
Speaker 2: Well, there is something different about music to invoke Claude Shannon.
Speaker 2: It's a highly organized and structured stimulus like language, and
Speaker 2: so in an information theory perspective, which is Shannon, your
Speaker 2: ability to predict what will come next in any sequence
Speaker 2: defines how structured highly structured it is. Even more so
Speaker 2: than language. Music is highly constrained. So I could say
Speaker 2: a sentence to you like this, Let's try this, the
Speaker 2: pizza was too hot to blank? What comes to mind?
Speaker 2: Eat yeah or touch yeah? I would not be likely
Speaker 2: to say the pizza was too hot to sleep. Once
Speaker 2: I say it, you understand what I meant, and you
Speaker 2: understand that I use the correct part of speech. I
Speaker 2: put a verb at the end, But it's an unlikely outcome.
Speaker 2: Music is even more constrained because there are only twelve
Speaker 2: notes in our scale, and there are I wouldn't call
Speaker 2: them laws of music theory, but customs of music theory.
Speaker 2: And there are rhythmic rules or customs.
Speaker 3: And so once you.
Speaker 2: Get going on a piece of music, its own structure
Speaker 2: constrains what the possible completions are, making it easier to
Speaker 2: remember and then easier to recollect, easier to store and
Speaker 2: easier to retrieve, and then moreover, as its own internal tempo.
Speaker 2: Once the beat is going, it's carrying you along, whether
Speaker 2: you're ready to go along with it or not. And
Speaker 2: so you're going to fill those slots with what needs
Speaker 2: to go there or your best approximation for it. And
Speaker 2: when you look at performing musicians, like typically the ones
Speaker 2: that work holiday ins on Friday night lounge bands and stuff,
Speaker 2: they might know two thousand songs where I would use
Speaker 2: the word no in quotes, they probably don't know every
Speaker 2: single note and every single rhythm.
Speaker 3: But they can approximate it.
Speaker 2: They can improvise and estimate it so that you don't
Speaker 2: really notice the difference.
Speaker 1: Well, that's actually a good segue into Parkinson's disease.
Speaker 2: How is music used there? So in all these cases
Speaker 2: of music is medicine. We're not talking about like a
Speaker 2: music module in the brain or a music medicine prescription
Speaker 2: that's straightforward, because music is doing different things in different
Speaker 2: parts of the brain, different aspects of the music are
Speaker 2: doing it, and Parkinson's is I'm so glad you brought
Speaker 2: this up. It's actually the best case for understanding this
Speaker 2: differentiation in Parkinson's disease. At some point, most patients will
Speaker 2: experience difficulty walking movement disorders in general, but walking in particular,
Speaker 2: and it's because the disease degrade circuits in the basal
Speaker 2: ganglia that are required to maintain a smooth and steady
Speaker 2: gait and to orchestrate the movements of one foot has
Speaker 2: to go after the other and you have to put
Speaker 2: it down at a certain time where you end up
Speaker 2: with both feet in the air at the same time,
Speaker 2: and that's not good for walking. And the circuits that
Speaker 2: allow you to walk rely on an internal intrinsic timer
Speaker 2: in the brain, a clock, and that's what gets degraded.
Speaker 2: If you listen to music that has the tempo of
Speaker 2: your natural gait, you have neurons, neuronal clusters that were
Speaker 2: not damaged that synchronize to that pulse, and then they
Speaker 2: can act as an external clock that allows you to
Speaker 2: walk smoothly and continuously.
Speaker 1: What else besides dementia and Parkinson's, where else do we
Speaker 1: see therapeutic effects?
Speaker 2: Well, I think one of the big ones is an anxiety.
Speaker 2: Dentists figured this out a long time ago. They play
Speaker 2: you what's supposed to be relaxing music to reduce your anxiety,
Speaker 2: which reduces swelling and inflammation.
Speaker 1: And why does that work?
Speaker 2: Some music we find to be relaxing, some we find
Speaker 2: to be stimulating, some we find to be inspiring. And
Speaker 2: the difficulty is, there's no one music that will do
Speaker 2: those things for everybody. In fact, there's no one song
Speaker 2: everybody likes. There's no one song everybody hates. It's subjective,
Speaker 2: like your taste for food. You know, why doesn't everybody
Speaker 2: like Indian food? I love food, Not everybody does. You
Speaker 2: have our own taste. It seems as though we have
Speaker 2: an esthetic module each of us that governs things like
Speaker 2: our taste and colors and people and tastes and music.
Speaker 2: And we actually showed in a PNAS paper that a
Speaker 2: person's preferences for certain musical combinations is correlated with their
Speaker 2: preferences for certain color combinations, which seemed completely crazy to me.
Speaker 2: It just seems so far fetched. But there's this underlying
Speaker 2: aesthetic module that we can't account for yet.
Speaker 1: What was the argument there, did you guys forward a hypothesis?
Speaker 1: I read no?
Speaker 2: Oh well, I mean there was some hand waving. Yes,
Speaker 2: there's an aesthetics module, and yeah, I mean to some extent,
Speaker 2: it had to do with consonants and dissonance. Do you
Speaker 2: like to see contrasting colors and contrasting chords? Do you
Speaker 2: like to see things that are more consonant and harmonious?
Speaker 2: But sharp edges and the metaphorical sharp edges and music.
Speaker 2: But apart from that, it was pretty speculative.
Speaker 1: So let me double click on this issue about individual differences,
Speaker 1: because one thing that's clear is across the population, some
Speaker 1: people don't really like music that much. Other people love music,
Speaker 1: it's a big part of their lives. But on one
Speaker 1: on the spectrum, you just it's sort of meaningless to
Speaker 1: many people. So how do you interpret that?
Speaker 2: Well, I just look at this as as a necessity
Speaker 2: of Darwinian theory, which is that we can't all be alike,
Speaker 2: or we'd you know, genetically or behaviorally or we would
Speaker 2: all be wiped out by a single opportunistic virus. So,
Speaker 2: you know, a cornerstone of Darwinian theory, as you teach it,
Speaker 2: as I teach it, is descent with modification and random mutation.
Speaker 2: And so you know, most random mutations end up being unobservable.
Speaker 2: Some of them we see a phenotypic variation, that is
Speaker 2: a behavioral variation. And in that case, yeah, ten percent
Speaker 2: of the population probably don't like music, and they don't
Speaker 2: understand why the rest of us spend so much money
Speaker 2: and time on it. Ten percent of the population probably
Speaker 2: don't like chocolate. I find that so impossible to believe,
Speaker 2: but they don't. And then there are you know, some
Speaker 2: percentage of the population don't like sex. They tend not
Speaker 2: to pass that on through reproduction, but that trait, but
Speaker 2: it's the way it works.
Speaker 1: How do you think music fits into the story of
Speaker 1: evolution and human evolution in particular.
Speaker 2: So Stephen Pinker famously threw down a gauntlet in nineteen
Speaker 2: ninety seven when he said that he thinks that music
Speaker 2: has nothing to do with evolution, that it was just
Speaker 2: sort of a byproduct of other things that we developed,
Speaker 2: like language. He called music auditory cheesecake, And what he
Speaker 2: was saying was that, well, we didn't really evolve to
Speaker 2: like cheesecake. We evolved to like sweets and fats because
Speaker 2: in the very small amounts they were available across evolutionary
Speaker 2: time periods to it was adaptive to seek them out. Now,
Speaker 2: if you get cheesecake, it'll just you know, you know,
Speaker 2: spike your blood sugar levels and be bad for your health.
Speaker 1: I'm curious if you have a different view on it,
Speaker 1: whether there's a role in evolution for music.
Speaker 2: We do have some data and I'd like to share
Speaker 2: that with you, our and our listeners. So to begin with,
Speaker 2: I mean, just as a resource, I would mention Stephen
Speaker 2: Mithen's book The Singing Neanderthals, where he makes the case
Speaker 2: that music was a proto language that preceded, you know,
Speaker 2: linguistic language speech. I would say the evidence that we
Speaker 2: have from neuroanatomy is that, from the work that Vanode
Speaker 2: Menon and I have done in others, those circuits that
Speaker 2: are engaged with music, listening and performing are phylogenetically older
Speaker 2: than the speech circuits. And that's the reason why Gabby
Speaker 2: Giffords was able to recover speech after she was shot
Speaker 2: in the head and lost the ability to speak. It's
Speaker 2: called melodic intonation therapy. We can take somebody who's lost
Speaker 2: speech ephasic expressive aphasia and teach them to sing what
Speaker 2: they need to communicate.
Speaker 1: So give us an example of that. What Gabby Gifference does.
Speaker 3: Well.
Speaker 2: She could not speak, but she might have been taught
Speaker 2: things like I need a glass of water, show me
Speaker 2: to the bathroom, I'm ready for bed now. She could
Speaker 2: sing those things perfectly, and through neuroplasticity, the brain rewired
Speaker 2: itself by passing those damaged circuits using the intact music circuits.
Speaker 2: They are phylogenetically, that is, evolutionarily older. That's one piece
Speaker 2: of evidence. Another is if we look at contemporary hunter
Speaker 2: gatherer preliterate societies or all around the world that have
Speaker 2: been cut off from Western civilization, and we make the assumption, David,
Speaker 2: that they're living life now pretty much as they have
Speaker 2: for ten or twenty thousand years, and all of them
Speaker 2: use music for a number of things, not just a
Speaker 2: single thing, but the emerging ideas that music evolved as
Speaker 2: many things did, not for a single to solve a
Speaker 2: single adaptive problem, but multiple problems, and one of them
Speaker 2: was how do you encode knowledge in a pre literate society.
Speaker 2: We've only had a written language for five thousand years.
Speaker 2: We've been on the planet ten or twenty times. As
Speaker 2: long as that, we still had to remember things like, oh,
Speaker 2: don't go over that hill there, because my grandfather went
Speaker 2: over there and they killed him because they're very vicious
Speaker 2: and warring, and so you know, don't go there. And
Speaker 2: when this water well runs dry, this is a route
Speaker 2: to the other well, the supplementary one. Don't eat that
Speaker 2: plant unless you boil it in this particular way. This
Speaker 2: kind of knowledge is embedded in song in pre literate
Speaker 2: hunter gatherer tribes and probably has been for a long time.
Speaker 2: Mothers soothing their infants to imprint their infant on their
Speaker 2: voice so that if they become separated, the infant will
Speaker 2: know the sound the mother's voice. So we've got knowledge,
Speaker 2: we've got bonding between mother and infant. We have social bonding.
Speaker 2: Singing around a campfire to ward off a neighboring tribe
Speaker 2: or predators as a way to defuse interpersonal tensions within
Speaker 2: a tribe and to protect you from outside invaders.
Speaker 3: Lots of different uses.
Speaker 1: Let me double click on this for a second. Do
Speaker 1: you feel that music is universal in terms of when
Speaker 1: you compare across culture around the world, or are there
Speaker 1: important differences locally both.
Speaker 2: Music is a cultural universal. There is no known culture
Speaker 2: now or any time in the past that lacked it.
Speaker 2: In David Huron's words, music is marked by its ubiquity
Speaker 2: and its antiquity, and there are huge local variations. One
Speaker 2: thing in common is we all have the octave, which
Speaker 2: is defined by frequencies that are double or having of
Speaker 2: one another hundred hertz, two hundred hertz, fifty hertz, all
Speaker 2: the same. We perceive them as perceptually very similar um
Speaker 2: similar notes. We give them the same name. In Western system,
Speaker 2: there's middle C and there's high C, and there's low C,
Speaker 2: things like that.
Speaker 3: But the way we divide up the.
Speaker 2: Octave into pieces is different across cultures. We divide the
Speaker 2: octave up into twelve pieces, and we tend to use
Speaker 2: only five or seven of the notes at a time.
Speaker 2: The patterns that we make once we've divided the octave,
Speaker 2: the way we combine them, either sequentially or simultaneously melodies
Speaker 2: and chords are different. And that's why Chinese opera and
Speaker 2: the music of Sub Saharan Africa sounds so different to us.
Speaker 2: It's based on different customs and a different system. And
Speaker 2: it's not the case that our music is better or
Speaker 2: that if only you went into the Amazon and played
Speaker 2: the indigenous people their mozart, they would feel that they
Speaker 2: had suddenly heard from God himself. It doesn't work that way.
Speaker 2: We've done the experiment.
Speaker 1: What is their impression of it?
Speaker 3: Eh? Meh? Yeah.
Speaker 1: Presumably whatever you've grown up with culturally affects your enjoyment
Speaker 1: of what you're hearing, right.
Speaker 3: Very much.
Speaker 2: So. Yeah, we imprint on the music we're raised on,
Speaker 2: and so we implicitly learn the grammar of our music
Speaker 2: the way we implicitly learn the grammar of our language.
Speaker 2: As Chomsky had said, here's a little test. Hang on
Speaker 2: a second. Okay for the listener, Dan has des grabbed
Speaker 2: his guitar, So we all know implicitly, uh scales, even
Speaker 2: if we don't realize we do. Now you're expecting another note.
Speaker 2: You're probably expecting this one.
Speaker 1: Thank God about that? Yeah, otherwise.
Speaker 3: That doesn't sound bad. But that sounds quite not quite right.
Speaker 2: And we know chords. We know that if I go
Speaker 2: it wants to go somewhere.
Speaker 3: I can't just stop I've got to come back to.
Speaker 2: Or or.
Speaker 3: There's some options, but not unlimited options, right.
Speaker 1: And I've talked in many episodes about how fundamentally the
Speaker 1: brain is a prediction machine. It's just it is trying
Speaker 1: to guess ahead at what's going on. It's got an
Speaker 1: internal model of what's coming next. So in those cases,
Speaker 1: let's say, with the chords that you were playing, is
Speaker 1: it the case that I had certain predictions because of
Speaker 1: the culture I've grown up in. To what extent would
Speaker 1: that be universal about what chorn comes next?
Speaker 2: Absolutely, and something I very much appreciate about you, because
Speaker 2: this is not something that all cognitive scientists cognitive scientists
Speaker 2: talk about, but you and I, I think, have been
Speaker 2: big proponents for this idea that if the brain is
Speaker 2: if the brain is nothing else, it is a giant
Speaker 2: prediction machine. That is its job. It's just based on
Speaker 2: what we've heard over and over and over again. And
Speaker 2: the job of the composer and the performer is to
Speaker 2: reward those expectations just enough of the time that you
Speaker 2: feel like you're following along with the story as it unfolds.
Speaker 2: But they have to surprise you just enough of the
Speaker 2: time that you've learned something, or you get that little
Speaker 2: hit of oh, isn't that interesting? As much as I
Speaker 2: was trying to predict what comes next, they came up
Speaker 2: with something even better than I could have imagined.
Speaker 1: Just like with everything in life, there's a spectrum between
Speaker 1: novelty and familiarity and all the sweet spot is in
Speaker 1: between that. Somewhere on that note, what is the reason
Speaker 1: that we care for rhythm so much? Do you feel
Speaker 1: as I do that it has to do with predictability,
Speaker 1: where the brain says, oh, now I know what's coming next.
Speaker 1: There's the next beat, in the next beat, and there's
Speaker 1: something very satisfying about having some structure of prediction, and
Speaker 1: then there's surprises thrown on top of that.
Speaker 2: It's because the brain's a prediction machine that rhythm is
Speaker 2: meaningful to us. There are populations of neurons that fire
Speaker 2: in synchrony with the beat, with the tempo that sets
Speaker 2: us up for movement. And I mean that metaphor and literally,
Speaker 2: music is possibly the only art form that makes you
Speaker 2: want to wiggle your body in response to it. People
Speaker 2: aren't standing in front of the Mona Lisa and dancing.
Speaker 3: Although they do, they.
Speaker 2: Seem weird and they might get kicked out of the louver,
Speaker 2: but we dance to music because we can't help it.
Speaker 2: And in the neuroimaging studies I've done all of them,
Speaker 2: where we ask people to stay still, we still see
Speaker 2: activity in their premotor cortex and their motor cortex that
Speaker 2: they're trying to suppress. And then on the metaphorical movement, yes,
Speaker 2: rhythm is important because it's telling us that there is
Speaker 2: more to come and we want to know what that is.
Speaker 2: It sets up a narrative momentum and when a musician
Speaker 2: could play around with that rhythm. If you listen to
Speaker 2: what Stevie Wonder does and the opening to Superstition, I
Speaker 2: can't replicate this exactly, but he's playing around on the
Speaker 2: high hat. He's setting up a beat. The high hat's
Speaker 2: that little symbol and ordinarily a normal drummer would just go,
Speaker 2: but Stevie doesn't goes. He's playing around. No, two times
Speaker 2: are the same, and we may not notice it because
Speaker 2: he keeps the underlying pulse there, but it is ear
Speaker 2: Candy Man. It is just so interesting for the brain
Speaker 2: to take all that in, even at a subliminal level,
Speaker 2: that there's so much going on, and not only is
Speaker 2: he changing in the rhythm. He's moving his stick around
Speaker 2: so he gets the bell of the symbol, he gets
Speaker 2: the edge, he gets the middle, he gets different sounds
Speaker 2: out of it.
Speaker 1: So this is a good segue into something I've been
Speaker 1: wanting to ask you, which is, what is your take
Speaker 1: on artificial intelligence and music the future of And there
Speaker 1: are two ways to think about this, of course. One
Speaker 1: is AI composing music. Another is AI finding the perfect
Speaker 1: music for you. Maybe there are other ways to think
Speaker 1: about it as well, But tell us your take on
Speaker 1: the future.
Speaker 2: AI composing music. I look at it this way. I
Speaker 2: have a friend, a novelist, Gail Jones, wonderful novelist, who
Speaker 2: says that AI music now is like those artificial flowers
Speaker 2: at a holiday inn. You walk in the lobby, you
Speaker 2: see this big display and you go, wow, isn't that nice?
Speaker 2: And you get up close and you realize they have
Speaker 2: no nice odor and they're plastic, And so AI music
Speaker 2: at a distance probably sounds just fine. And it's already
Speaker 2: crept into advertising on social media. It's being used in
Speaker 2: the background. It's sonic wallpaper. It's kind of like the
Speaker 2: painting in the bedroom of that same holiday in room
Speaker 2: it's like, Okay, it's covering the wall. It's kind of nice,
Speaker 2: but I'm not going to sit there and stare at
Speaker 2: it for hours. I think that you and I subscribe
Speaker 2: to Dan Dennett's functionalism, the idea that in theory, all
Speaker 2: of our thoughts, hopes, desires, and beliefs, all of our
Speaker 2: mental activity can be redo to brain activity, and that
Speaker 2: brain activity can be characterized by patterns of neural firings
Speaker 2: and connections if you could replicate a human brain and
Speaker 2: add in the right amount of random factors. I think
Speaker 2: in theory, yes, AI music could be great. I don't
Speaker 2: like the thought of it, but I mean that's the reality.
Speaker 2: But for now, I don't think AI music is going
Speaker 2: to be a threat to real music and real feeling.
Speaker 2: But you nailed it on the head. Where I think
Speaker 2: AI can be the most use is helping us to
Speaker 2: find music that we like. Most of us listen to
Speaker 2: a couple of thousand songs maximum, over and over and again,
Speaker 2: and occasionally let in a few new ones, and those
Speaker 2: can be comforting and rewarding, but they can dig deep
Speaker 2: neural ruts such that we get tired of them and
Speaker 2: we want something new. There are now two hundred million
Speaker 2: songs across the streaming services, with a one hundred thousand
Speaker 2: new ones being uploaded every day. So how do you
Speaker 2: find what you like? The major streaming services have recommendation systems.
Speaker 2: They don't work particularly well for me, But AI in
Speaker 2: principle can extract hundreds of features latent features for music
Speaker 2: and build a multi dimensional model, a higher dimensional manifold
Speaker 2: of musical structure and DNA that might have one hundred
Speaker 2: and fifty orthogonal dimensions, and set up a kind of
Speaker 2: universe of music where things that are where each song
Speaker 2: is like a planet, and planets that are near each
Speaker 2: other are going to be similar, not just structurally, but
Speaker 2: in an emotional space where they're likely to cause a
Speaker 2: similar emotional reaction in a given listener, knowing what your
Speaker 2: own personal space is, right, It's not going to be
Speaker 2: something that is entirely objective and prescriptive and one one
Speaker 2: hundred and fifty dimensional map for everybody. They'll have to
Speaker 2: be to maps for each person, because your tastes are
Speaker 2: different than mine. As my grandfather used to say, if
Speaker 2: everybody liked the same things, they'd all want to get
Speaker 2: with your grandma, I'm going.
Speaker 1: To steal that line if you don't mind, when I'm
Speaker 1: a grandfather. What have I not asked you that I
Speaker 1: should ask you?
Speaker 2: I wanted to ask you of the many successful books
Speaker 2: and highly regarded books you've written, did you write them
Speaker 2: because you wanted to read them and you couldn't find them?
Speaker 2: Or did you write them because you just thought that
Speaker 2: you had a different take on something than others?
Speaker 1: Oh? No, I actually know precisely why I write my
Speaker 1: books and who I'm writing them for, which is I'm
Speaker 1: writing them for the younger version of me that didn't
Speaker 1: know those particular facts when he was younger, but would
Speaker 1: have loved that. That's who I'm always writing for.
Speaker 2: You know, Joni Mitchell taught me about something about songwriting
Speaker 2: that was really transformative and my songs I've been writing
Speaker 2: since I I was eighteen, but since Joni told me
Speaker 2: this in two thousand and five, I not only did
Speaker 2: my current songs get better, but I went back to
Speaker 2: the old ones and started rewriting them. And what she
Speaker 2: said was, you don't write a song because you figured
Speaker 2: something out. You write it in order to figure something out.
Speaker 1: That was my friend and colleague Dan Levitton, neuroscientist, cognitive psychologist, writer, musician,
Speaker 1: and record producer. So what has emerged from a couple
Speaker 1: of decades of the study of music in the brain
Speaker 1: is that music can't be understood simply as different pitches
Speaker 1: hitting the ear. The sounds of music trigger a neural
Speaker 1: hurricane of spikes on the inside of the skull, and
Speaker 1: this correlates with the pitch in rhythm and timbre, but
Speaker 1: it jins up a silent neural symphony, and that activity
Speaker 1: is closely tied in with our emotions and it pulls
Speaker 1: strings to our memories. We don't just hear music, we
Speaker 1: actually resonate with it neurally. So the brain doesn't just
Speaker 1: process music, it magnifies it, which shows us once again
Speaker 1: that the ultimate instrument is not the piano or the guitar,
Speaker 1: but the one between our ears. Go to eagleman dot
Speaker 1: com slash podcast for more information and to find for