Monday, September 28, 2009
How does human song relate to the songs of other animals? We talk to Dr. Aniruddh Patel about the connection between human and animal songs. We also discuss how song relates to language, and other cognitive functions.
MAUREEN CAVANAUGH (Host): I'm Maureen Cavanaugh, and you're listening to These Days on KPBS. If the ability to vocalize and put together regular and predicable sounds is not limited to humans, then why is speech something only humans can do? What is the difference between song and speech? Do they originate in different parts of the brain? Are there things about our brains we can learn from the songs of the other animals? The question of what connection human and animal song may have had tantalized natural biologists all the way back to Darwin. And it's still a popular subject in comparative biology. My guest, Dr. Ani Patel, is a neuroscientist who studies the links between music and language in the brain. He's found that in humans, speech and music share deep and critical connections. And, he's here to tell us what link our ability to sing has with the songs and communications produced by other species. Dr. Ani Patel is the Esther J. Burnham Senior Fellow at the Neurosciences Institute in La Jolla. Dr. Patel will also be giving a lecture tonight at the San Diego Natural History Museum.
DR. ANI PATEL (Esther J. Burnham Senior Fellow, Neurosciences Institute): Tomorrow.
CAVANAUGH: That’s tomorrow. Sorry. Correct me right off the bat. That’s very good. Dr. Patel is going to be giving that lecture tomorrow night at the San Diego Natural History Museum. And I want to let our audience know if you have questions or comments about animal song, human song, the relationship between the both of those songs, 1-888-895-5727 is the number to call. That’s 1-888-895-KPBS. So, Ani, your lecture Tuesday night is called “Human Song in Biological Perspective: The Singing Brain.” What topics do you plan to discuss during that lecture?
DR. PATEL: Well, I’ll be talking about song from the standpoint of how it’s produced physically by the human body and how the way we do it differs from the way other animals do it. I’ll be talking about song in relationship to speech, how the brain controls song and how that differs from how the brain controls speech. I’ll be talking about some of the functions that song has for humans as in comparison to other animals and some ways in which song affects the brain.
CAVANAUGH: Yeah, you know, singing comes so naturally for most people. It’s something we do as children. We don’t even think about breaking it down. But in your studies, you think about breaking down the idea of singing from speech and also connecting it to other animals. How do you take something so natural and find out where it comes from?
DR. PATEL: Well, part of it is applying some of these new tools from neuroscience that have just come, really, to be available in the past decade or so where we can look at healthy, living human brains while they do complicated things like thinking or talking or singing. And then one of the discoveries, for example, has been how much of the brain is utilized by song. I guess you may be familiar with the old idea that language is a kind of a left brain thing and music…
DR. PATEL: …and singing is a right brain thing.
DR. PATEL: Well, one of the first things we learned from looking at human brains while they were doing these things is that’s just a big oversimplification, that language and music and singing use both sides of the brain. There’s some bias. Language, spoken language, tends to be more heavily reliant on the left side of the brain, singing and other types of music, somewhat more reliant on the right side, but there’s just a tremendous amount of overlap, that the song uses a lot of the brain.
CAVANAUGH: Now, what I – from what I understand from what I’ve heard, different – other animals use song as a method of communication. It’s almost like the way they talk to each other. Is that right?
DR. PATEL: Well, actually it’s a little bit more complicated than that. So birds – let’s talk about birds for example. Songbirds have songs and they also have non-song communication that they have little calls that they give, maybe a begging call a young chick might give to its mom for food. Song is used for particular things and in most songbirds, it’s the males that sing and it’s thought to be kind of an advertisement for mating. The male is basically advertising himself as an available mate for females and trying to attract them with his song and also trying to ward off potential competitors, other males. So it has more of a kind of a reproductive function, at least in songbirds.
CAVANAUGH: Well, let’s hear. You have some clips of some songbirds. You brought two clips from the Eastern Meadowlark and the first clip we plan to play – let’s just go ahead and play that right now. Give us that clip.
(audio of song of the Eastern Meadowlark)
DR. PATEL: Yes, so that’s an Eastern Meadowlark. It’s – and I brought that clip because it’s a beautiful, interesting birdsong but I wanted to illustrate just how complex it is. So one of the things that birds do that we don’t do is that our voice box sits up at the top of our trachea and we have one set of vocal folds. They actually have a voice box that’s divided into two separate individual sides, so they can – and they have independent control of these two sides. One side is controlled by one side of the brain, and the other by the other side of the brain. So – And that voice box of theirs sits down at the base of their trachea, near where the bronchia and the trachea intersect. So they basically have the ability to produce much more complicated songs than we ever could because of this two – kind of two independent source mechanism. And one way to appreciate that is to take a song like that that sounds so simple and slow it down, and let’s play it slowed down five times, and I think you’ll hear a lot more interesting detail that you don’t pick up when you listen at the normal rate.
(audio of slowed song of Eastern Meadowlark)
DR. PATEL: So what you hear at that rate is you almost hear like the bird singing almost a little musical scale embedded in that song, which you never would pick up when you heard it at normal speeds. Now this raises a whole ‘nother set of questions, which is do birds really sing in musical scales? And every once in a while you hear little riffs that sort of sound like familiar scales or familiar musical patterns to us but, by and large, it doesn’t seem that they do it in the same way we do where they have a set of pitches that they draw on and they recombine them in different ways to make melodies. But that was a kind of intriguing little counterexample.
CAVANAUGH: I’m speaking with Dr. Ani Patel. He is a neuroscientist studying the songs, songs in human beings, songs in different animals. And one thing I wanted to say is the – when we played those two clips, the first one was – immediately you thought of a birdsong. It didn’t sound like anything else but something being produced by a bird. The second one sounded a little bit more like human music.
DR. PATEL: Uh-huh. Interesting. Well, part of that is that by slowing it down, we were bringing it down into a frequency range that is closer to our own voice. Birds tend to sing much higher than we can. So that’s – And then also I think the speed, again, puts it more into our realm of hearing. Shall we try the other clip that we…
CAVANAUGH: Yes, why…
DR. PATEL: …brought along, too?
CAVANAUGH: …not? Why not? You brought back two clips of a humpback whale song. What will we hear in the first clip?
DR. PATEL: Okay, so the first clip is a recording of a couple of phrases, just a couple of phrases because these songs can be very long. That meadowlark song lasted a couple of seconds, humpback whale songs can last half an hour and then they repeat them so actually they can last even longer than that. But we’ll be hearing just a couple of phrases and it’s in a completely different time scale and just listen how slow this song is when it’s played at normal speed.
(audio of song of humpback whale played at normal speed)
DR. PATEL: So – Can I just make a comment about that?
CAVANAUGH: Yes, please do.
DR. PATEL: So one of the things I’ll be talking about tomorrow is the differences in the ways different animals produce song. Now, humpbacks are mammals. They evolved from land mammals and the ancestors probably produced songs in the same way we and birds do; they expel air through their mouth while they vocalize. Well, humpbacks, movies that have been taken of humpbacks singing underwater showed that they’re not expelling any air. There’s no bubbles coming out of their bodies as they sing. They’re doing this somehow without releasing any air. They’re not opening their mouths, it’s all internally generated sound. How do they do that? That’s one of the things I’m going to be talking about tomorrow.
CAVANAUGH: Wow. How do they do that?
DR. PATEL: Well, they – Briefly, they do have vocal folds sort of like ours so they’re massive, as you can imagine…
DR. PATEL: …compared to ours. Ours are the size of a thumbnail, theirs are sort of the size almost like imagine the inner tube of a tire. And they do pass air through these vocal folds but then instead of expelling it out of their mouth, they capture it in kind of a sac, which allows them to recycle it because air is a precious resource underwater and you can’t just be blowing bubbles when you sing, otherwise every couple of seconds you’d have to come back to the surface.
CAVANAUGH: Right, right.
DR. PATEL: So…
CAVANAUGH: And you wouldn’t be able to do it for half an hour.
DR. PATEL: Right.
CAVANAUGH: Let’s hear the faster version of the whale song.
(audio of faster version of song of the humpback whale)
DR. PATEL: Yeah, and that – I think what’s neat about that is it sort of sounds like a birdsong…
DR. PATEL: …and it raises the question of how do the whales hear their own song? I mean, we hear at a particular rate just as we speak at a particular rate. Are they actually hearing it more sped up, so to speak, than we do? That was sped up five times, and for us it’s almost difficult to hear it as song because these phrases are so long. But maybe to a whale it sounds a little bit different than it does to us.
CAVANAUGH: I’m speaking with Dr. Ani Patel, and he is a neuroscientist studying song at the Neurosciences Institute in La Jolla. And we’re taking your calls if you have a question or a comment for Dr. Patel. The number is 1-888-895-5727, that’s 1-888-895-KPBS. Okay, so you’ve kind of explained to us a little bit why animals might communicate to one another in song. Why do humans sing?
DR. PATEL: Oh, that’s a great question. So as I mentioned with animals, by and large, it seems like song plays a reproductive function. It’s an advertisement for females that’s usually done by males. Human song seems to be a different ballgame. I mean, both males and females sing, we do it for a really wide variety of reasons. Of course, there’s songs are wonderful at expressing deep emotions in ways that’s difficult to do in ordinary speech, but songs can also be just for rituals. I was at a child’s birthday party yesterday with my kids and everybody sang “Happy Birthday” as you do at a party, and it certainly wasn’t about creating great beauty out of sound or evoking wonderful emotions, it was just about kind of a ritual to recognize that this is somebody’s birthday and this is a way we mark it, and so songs have that kind of ritual function. They also are wonderful pneumonic devices. All the old epics and ballads that we know about “The Iliad,” “The Odyssey,” the Indian Vedas, these are all chanted and sung. And song seems to have a way of getting words deeply into our brain and keeping them there so that sometimes they’re even the only thing that is well remembered. When people have Alzheimer’s disease and they can’t even recognize their family, they – colleagues have shown that they still recognize familiar songs and are sensitive to them.
CAVANAUGH: And even young children sort of begin to hum or vocalize some sort of music, you know, no particular tune but they’re sort of humming and making up their own little songs.
DR. PATEL: Absolutely. It emerges early in life. And Darwin was fascinated by song, partly because he saw it not as this select province of a few talented people but as a basic human thing that we all did to some level and that maybe it was very important in our ancestors. In fact, he believed that before our ancestors spoke that they sang, that they had something like a birdlike courtship system that involved vocalizing, both the males and the females as a way of attracting other mates. And very hard to know if that’s true but his basic point was song is biology.
CAVANAUGH: Now as you differentiate what humans do from what animals do, and they’re both called song, both sort of forms of song, is there a difference between what we recognize as music and animal song?
DR. PATEL: Well, that’s a good question. And, I mean, I think to a certain extent music is in the ear of the listener.
CAVANAUGH: Yes, it is.
DR. PATEL: And there are people who cross the boundary. So Jonathan Harvey, who’s a pioneer of computer music, has taken birdsongs like the one we played, in fact birdsongs from California, and has slowed them down and interwoven them into his musical compositions because he hears them as music. And this is a repeated refrain in the history of western music. Olivier Messiaen had a similar thing he did. So, you know, I think part of the reason songs of other species fascinate us is they do have some musical properties. They have phrasing, they have repeating patterns, sometimes they strike our ears as beautiful. They may not be used in the same way that we use our music but they clearly inspire us as something related to music.
CAVANAUGH: We’re taking your calls at 1-888-895-5727. Let’s take a call right now and speak with Ian in Solana Beach. Good morning, Ian. Welcome to These Days.
IAN (Caller, Solana Beach): Good morning. And I – my question is basically with regard to whale communication.
DR. PATEL: Okay.
IAN: When submarines communicate underwater, they use very long wave lengths, short and low frequencies in order to go long distances. Now do whales use subsonic communication in order to communicate with other whales at far distances?
DR. PATEL: Well, basically, yes. Whales use very low frequency sounds which travel much further in the ocean than high frequency sounds. And, in fact, it’s been shown that some of the whale calls that are low – very low frequency, like the blue whale song, which is a very simple song, actually can be heard over a thousand miles away underwater. In fact, there’s an interesting book you might want to take a look at called “Thousand Mile Song” about the whales and the songs of whales, and that’s one of the things it talks about is this ability to communicate over vast distances for the low frequencies.
CAVANAUGH: Let’s take another call now. Ian is calling in San Diego. Good morning, Ian, and welcome to These Days.
IAN (Caller, San Diego): Good morning. Thanks for taking my call.
CAVANAUGH: Yes, how can we help you?
IAN: Yeah, I just had a question regarding the different songs or speeches between different species, for example whales and birds. As far as your studies and the repeated patterns, possibly, of different individuals and maybe some of the more common – You know, first of all, are there, you know, repeated patterns between two, you know, two or more different whales or different birds that are repeated, you know, that you find in your studies, and possibly, you know, what are those mean – you know…
DR. PATEL: Yeah.
IAN: …what are those meaning as far as are they communicating…
DR. PATEL: Right.
IAN: …so maybe just your comment on that.
DR. PATEL: Sure. You know, that’s a very good question. So the humpback whale has a fascinating whale song. One of the reasons it’s fascinating is that in any given breeding season, all the males in a given population actually converge on the same song. They stop singing during the non-breeding season but then they pick up again the next year kind of where they left off the year before, and the song has changed and it does continue to change over the cycle of the breeding season but every male seems to want to sing the same song so the males will all adapt to sing one song. That’s different from birds as far as we know. In fact, Tim Gentner, a biologist at UCSD, has shown that starlings, when male starlings sing songs, they do individuate themselves and part of – and they even sort of have some recognition of each other as individuals based on who’s singing. So how this relates back to function is not totally clear but basically the point is that animals don’t all sing the same song in birds, and in whales, at least humpback whales, they do all seem to want to sing the same song. So it kind of depends on the species as far as this issue of how similar the songs are to each other.
CAVANAUGH: I wonder, Dr. Ani Patel, have you slowed down or speeded up any human songs to find any greater meaning in that kind of expression?
DR. PATEL: Oh, that’s a really interesting question. I’ve never done that. It’s sort of an interesting observation that most human song is slower than speech. When we sing, we tend to slow down and, in fact, that’s almost a universal. There are very few cultures that I know of where you sing faster than you can talk or than you typically talk. Song tends to be much more repetitive than speech. You’re, you know, you sing a refrain over and over again, for example. So it’s doing things differently. Part of the slowness and the repetitiveness, I think, is partly because song invites you to join in, invites you to participate and bond through listening or through singing along in a way that speech does not. And speech is typically alternation song, it’s very often synchronization and communion through song.
CAVANAUGH: Now this question I think goes to the heart of some of your research and that is if, indeed, the ability to produce music is in one side of the brain and the ability to produce speech is in the other, how is it that we sing songs with words?
DR. PATEL: Ah. Well, actually the science that we’ve been doing and many others have been doing has been showing that the left-right thing is more of a kind of a general bias. It’s not a complete separation. So we do rely more on the left side for the words and a little bit more on the right for the music. And to sing, you kind of have to put the left and right side together, and that happens all the time in song. And, in fact, one of the things I’ll be talking about tomorrow is how singing after certain types of brain damage seems to actually change some of the wiring and connectivity in the brain and help recover speech functions because of these connections between song and speech.
CAVANAUGH: It reactivates some connections?
DR. PATEL: It seems to reactivate some connections, in some cases actually seems to strengthen existing connections. So song – that’s one of the themes of tomorrow’s lecture is that song is actually a biologically powerful force in our lives as is being shown by neuroscience studies of how the brain is changed by song after brain damage.
CAVANAUGH: You know, this is probably a stupid question but you know how some people sing better than others?
DR. PATEL: Umm-hmm.
CAVANAUGH: I wonder, is there any way of knowing if some animals sing better than others?
DR. PATEL: Oh, that’s really interesting because there’s actually a whole line of research now on female choice in animals…
DR. PATEL: …who sing…
DR. PATEL: …so they show that, first of all, females are choosy, they’re picky. They – when they listen to male songs they find some more attractive than others. Again, Tim Gentner at UCSD has done some work on this and to give you one example, he’s found that female starlings prefer longer songs. If you put them in a box and play them, they can see if they sit on one side, they hear shorter songs, if they sit on the other side, they hear longer songs. They prefer to sit on the side where they hear longer songs. Well, why is that? Well, it turns out longer songs tend to be made by older males and older males tend to be better provisioners of food at the nest. So basically this female preference seems to have something to do with picking a male that seems like it’s going to be a better father because the male is using the song to advertise himself. So I don’t know if you’d call that esthetic preference in the bird but the bird definitely has preferences about the kinds of songs it’s attracted to.
CAVANAUGH: One of the callers who couldn’t stay on the line was wondering if animals from different regions have different dialects or…
DR. PATEL: Oh, yes.
CAVANAUGH: …different ways that they produce their song?
DR. PATEL: Yeah. This is actually something that’s been studied really well in white crowned sparrows in the west coast. Luis Baptista, who passed away some years ago, was a wonderful bird biologist who studied dialects in white crowned sparrows and he found that these little birds learned their songs and depending on the neighborhood they grow up in, so to speak, they sing a slightly different song and then you can show that they learn these dialects by these kind of transplantation experiments where you take a baby born in this neighborhood and you raise it – or let it be raised in another neighborhood and it learns the local dialect. And they use that to distinguish each other when they look for mates and so forth. And Luis was a genius at – actually he could whistle all these dialects and gave these wonderful talks where he would whistle all these bird dialects and he was perfect at it.
CAVANAUGH: Great at parties.
DR. PATEL: Yes, exactly.
CAVANAUGH: Now, seriously though, the research into song has, as you say, applications in trying to reestablish the connections between speech centers and music centers. I wonder what other applications you see this research…
DR. PATEL: Umm-hmm.
CAVANAUGH: …being able to develop?
DR. PATEL: Well one of the areas that I think is just slowly starting to emerge that’s very interesting is the role of song in social behavior. So, you know, one of the things that music does, social music like singing, is it brings people together, it gives them a common goal, a common purpose and makes them feel like they’re on the same team working for something kind of larger than the self. And this has consequences for their behavior outside of musical settings, and this has been shown in experiments now where they do sort of musical activities and then they do some sort of post-music test where you give a person a game or a group of people a game where they can either compete or cooperate and it turns out they’re more likely to cooperate with each other if they’ve done a musical activity before than a nonmusical kind of social activity. So something about music and synchronizing your voices and your message seems to put people on a kind of similar emotional page and I think that’s very relevant for how we think about the role of music in, say, education.
CAVANAUGH: Yes, all those kindergarten teachers were absolutely right.
DR. PATEL: Well, as they usually are.
CAVANAUGH: All right, then. Well thank you so much for speaking with us. I really appreciate it, Dr. Patel.
DR. PATEL: Thank you, Maureen.
CAVANAUGH: I’ve been speaking with Dr. Ani Patel. He is the Esther J. Burnham Senior Fellow at the Neurosciences Institute in La Jolla. And Dr. Patel will be giving a lecture tomorrow night. His lecture is "Human Song in Biological Perspective: The Singing Brain.” It’s tomorrow night at 6:30 at the San Diego Natural History Museum. And if you would like to comment on anything that you’ve heard this morning on These Days, you can always go to KPBS.org/TheseDays and post your comment online. You’re listening to These Days on KPBS.