Using The Brain And Body To Make Music
Electronic musician Grace Leslie makes music that creates a sense of calm—long notes held on the flute, creating rich tones, and layered sounds. But her method for creating her songs sets her apart from most other electronic musicians: Leslie collects heartbeats, neuroelectric activity, and other biofeedback with sensors on people’s bodies. She feeds this input into a computer, which then converts the data into flowing waves of sound.
As a researcher at Georgia Tech in Atlanta, she explores how the brain and body react to music at the university’s School of Music. Leslie joins Ira to talk about her methods for creating art, and the mysteries of why music elicits an emotional response from those who listen.
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Grace Leslie is an electronic musician and researcher at the Georgia Institute of Technology in Atlanta, Georgia.
IRA FLATOW: This is Science Friday. I’m Ira Flatow. Listen for just a moment to this.
Pretty cool, huh? That’s the work of musician Grace Leslie. She’s also a professor of music technology at Georgia Tech in Atlanta. Grace’s method for making music sets her apart from most other electronic musicians. She uses things happening in her body, like brainwaves and heartbeats, to make music.
Grace Leslie’s work is the subject of our latest sci-arts video, which you can find at sciencefriday.com/bodymusic. Welcome to Science Friday.
GRACE LESLIE: Thank you for having me.
IRA FLATOW: So your style of music is called brain body music. What the heck is that?
GRACE LESLIE: So this is a style of music where I record my brain and body signals in real time. And then, I turn them into music when I’m onstage.
IRA FLATOW: I’m almost afraid to ask this question, what kind of body functions do you use to make your music? Just the brains and the heartbeats?
GRACE LESLIE: Well, using all different kinds of sensors, I can record EEG, which is voltage off of the scalp. So that’s showing us my brainwaves when0 I’m onstage. And then ECK or EKG, which is measuring my heartbeat. But I’ve also worked with skin conductance levels, which generally shows us what the arousal level is of the autonomic nervous system. And also breathing.
IRA FLATOW: Do you like one over the other? Are you specializing in any brainwaves, heartbeats?
GRACE LESLIE: I think, I would say that I specialize in the brain music performance aspect. But what I’ve learned over the course of performing this kind of music for almost 10 years is that they’re all very intertwined. And so, oftentimes, what I found is the best way to perform using brainwaves is actually to pay attention to the body.
IRA FLATOW: Now I noticed in your performance, which I was watching, it was really soothing music
GRACE LESLIE: Thank you.
IRA FLATOW: Is that intentional?
GRACE LESLIE: I didn’t necessarily set out to create music that would be soothing for the audience. But what I found is that when I went onstage and paid very close attention to my cognitive process, my body signals, what ended up happening is that I was reaching this very calm state. And then that ended up being communicated through the music.
And then, what I found from audience members is that they say that there’s an empathetic reaction that will happen just through witnessing this process and hearing these body signals being turned into music.
IRA FLATOW: Are there certain body sounds that work particularly better than others?
GRACE LESLIE: I think that the heartbeat is such an innate and evolutionarily important sound, I think it’s incredibly powerful to work with that onstage. I think that we have all these different kinds of inner bodily rhythms that our body uses that are all synchronized together, but they all work on different frequencies.
And so, our bodies will entrain to different kinds of musical sounds at all different frequency bands.
So, for instance, a musical beat that we hear very often is 120 beats per minute, which is the tempo of most dance music. And that’s a very, very natural tempo for us to walk to. And so, innately, we just, we really want to move to music that happens at that speed. But then when I create music that is synchronized to a heartbeat, that will usually happen around maybe 70 beats per minute.
And then also with a team at the MIT Media Lab, when I was a postdoc there, we did some research where we used a music track that would really subtly breathe with the participant. And when that was pegged around, maybe, six breaths per minute, we found that people, even if the music was just playing in the background, they would subconsciously slow down their breathing in order to synchronize with that music.
IRA FLATOW: Could you actually use breathing as one of the metrics that you use to create your music?
GRACE LESLIE: Yes, definitely. In some ways, that’s kind of what I got started with because I’m a flute player. And so, what ends up happening through the course of playing very slow music on the flute is that my breathing slows down very dramatically. I play these very, very long tones. And the breathing process when I’m performing this music is very obvious to the audience.
And so even without using the technology, you could say that the breathing pattern and process comes through very strongly in the music.
IRA FLATOW: OK since we’re in an audio and not a visual medium right now, say you’ve decided you want to make music with your heartbeat. Walk us through how a piece of your music comes together.
GRACE LESLIE: So I start with connecting the heartbeat to my software in some kind of way. So with the heart, I actually have the option of using the natural sound from the heart. So I’ve actually developed a stethoscope that I put a microphone inside and then record the heartbeat sound directly into my music track. But also I’ve worked with using electrocardiogram sensors over the chest.
And then I record that voltage into the software. And then I’ve developed an algorithm that can take any kind of physiological time series data, and then it kind of mashes together that signal with a prerecorded music sound. And by prerecorded, I mean that I generally have a bank of sounds of me playing the flute or me singing on my computer hard drive. But I can also record these sounds during an actual live performance.
IRA FLATOW: Why did you decide to get into this kind of music-body interaction?
GRACE LESLIE: Well, I think I was always very interested in trying to understand on a scientific level how music works in the brain and in the body. I was very lucky to be hired as more or less a lab tech at the Swartz Center for Computational Neuroscience at UCSD when I was studying music technology in grad school there. And what I found was that the kind of audio engineering mathematical background that I had from my music technology training actually transferred very naturally into studying EEG. Because when you think about it, a brainwave and a sound wave have a lot of shared mathematical properties. It’s only that the brainwaves are actually operating at a much slower speed.
And so I became very interested in trying to unpack these common shared features between music signals and brainwaves.
IRA FLATOW: Well, you do. You have some music that you use your EEG headset in some of your performances. How does that work? Are you watching the wave forms on a screen from your brainwave as you’re playing your flute?
GRACE LESLIE: So the EEG headset sends multiple channels of the EEG signal to my computer. I don’t really watch it on the computer. I just pay very close attention to how it sounds. And so instead of using biofeedback techniques where I’m actually trying to produce high levels of alpha signals or beta signals while I perform, I actually rather just pay attention to what the sound is. And then through a process of musical practice, I just learned how to be able to reproduce different types of timbres with this brain instrument.
IRA FLATOW: Interesting. Interesting. As we mentioned, you also are a researcher. What is it about the brain and music that interests you so much?
GRACE LESLIE: I think that when you look at the history of psychology research and early neuroscience, people have always used behavior as a way to have insight into how the brain works. And language for a long time was one of our best windows into the human brain. But the thing about music is that it operates like a universal, emotional language. And it has this ability to create this very potent emotional response. And for that reason– I think it’s a very, very important reason– just from a neuroscience point of view, in order to study the reason why music has this effect on us.
IRA FLATOW: You know, that’s true, because, you know, if you’re feeling one way, maybe you’re in a bad mood, you can turn on some of your old favorite music, and it evokes a feeling that you’ve had at a good time, and it can change your whole mood.
GRACE LESLIE: Right. It has this ability to conjure up a memory that you didn’t know that you had. And I think that in my research, I’m really interested in seeing is there any element of this response that happens at a very low physiological level. So is there any way that, you know, looking at the tempo of the music, the actual physical characteristics of the signal, is our brain and body and training to that music in a way that can take some responsibility for that incredibly strong effect that it has on us?
IRA FLATOW: Yeah. Because we also see that in people who are suffering from Alzheimer’s or other neurodegenerative diseases, and they’re in– they’re not responding. Sometimes if you play them the right music, you get this response you would not have expected.
GRACE LESLIE: Exactly. There’s a lot of research showing that music has very strong beneficial effects for all kinds of conditions. I actually worked with a neurology team at Dartmouth Hospital, and we are trying to see if we can engineer new music that can have a similar effect on the brain as more traditional neuro-stimulation protocols. And so we’re trying to see if we can kind of approximate electrical stimulation using a musical signal.
IRA FLATOW: And what kind of reaction– when you’re playing your music, that wonderful– it’s beautiful music I’ve been listening to. For an audience, how do they react? Are they in tempo with you or are they going off on their own now that you’ve played some evocative music?
GRACE LESLIE: Well, sometimes that’s hard to tell. But I have to say that this kind of music performance has been very different than other kinds of music that I’ve performed in the past, in that I’ve had audience members come up to me, I’ve had people send me emails. Some people who found my music on Bandcamp, for instance, and they say that the music has a very strong effect on them, has ability to conjure up memories of a better time, that they become relaxed, that it helps them sleep. And as a musician, I think that’s the most gratifying thing that I can hear.
IRA FLATOW: Just a quick note that I’m Ira Flatow, and this is Science Friday from WNYC Studios.
OK. So let’s talk about research that you’re doing. What kind of research moving forward are you looking into these days? Where would you like to take your research?
GRACE LESLIE: So my general goal is that I would love to see doctors be able to prescribe music to a patient. And I think we need to apply our scientific skills, we need to run the experiments, to be able to validate on a very physical level what is happening in the brain and the body when we play this music. How can we target very, very specifically engineered musical sounds for specific conditions in the brain or in the body? So I’m working with colleagues on a music that targets Alzheimer’s disease, epilepsy, anxiety.
IRA FLATOW: You know, Oliver Sacks wrote about this extensively, about music on the brain. You ever go dip into that?
GRACE LESLIE: Oh, yes. Of course. His research is so amazing. I’m very inspired by the way that he would work with individual patients. I think that in a lot of ways, the kind of individual response that each person has to music is the most interesting one. When we look at trying to develop a clinical intervention or to examine scientifically how music works in the brain, it’s kind of an unfortunate feature of the scientific method that we have to look and see what happens across a whole population of people. But there’s also incredibly interesting ways that you can scientifically look at what happens inside one person and their individualized response. And in the future, I would love to be able to work a little bit more in that direction.
IRA FLATOW: Yeah. Well, I hope you do. And I hope you’ll come back and tell us more about it when you do.
GRACE LESLIE: Oh, thank you.
IRA FLATOW: Unfortunately, we have run out of time, Grace. That was terrific. I’d like to thank Grace Leslie, musician and professor of music technology at Georgia Tech in Atlanta. And again, you can watch our video profile of Grace Leslie at our website at sciencefriday.com/bodymusic.
GRACE LESLIE: Thank you so much.
IRA FLATOW: One last thing before we go. Larry Kramer, writer and AIDS activist, died this week. Kramer was instrumental in helping reporters like me understand the scope of the outbreak of AIDS and its impact on New York City when it first broke out in 1981. He introduced me to victims, researchers, and doctors working on a disease no one understood. He was a loud voice at a time when others could not be heard. Condolences to all.