That Neuroscience Guy - Music

Episode Date: October 11, 2021

Have you ever wondered why music moves us so profoundly? Maybe you've questioned how we are able to create such powerful songs. In today's episode of That Neuroscience Guy, we discuss the neuroscience behind how we experience and make music. 

Hi, my name is Olof Kregolsen, and I'm a neuroscientist at the University of Victoria. And in my spare time, I'm that neuroscience guy. Welcome to the podcast. Do you like music? Like when you go out for a walk or you're driving, do you like to play music or sing along or even play a guitar and make music yourself? I love music. On today's podcast, we're going to talk about the neuroscience of music. Okay, to begin, first of all, let's go through a review of the pathways in the brain that allow us to listen to and understand spoken language, in addition to produce it. Well, obviously, sound comes in through the ear. And in the inner ear, sound is transferred to the auditory nerve. That auditory pathway then, from the auditory nerve,

goes to a region of the brain that's called the auditory cortex. It's a midbrain region that's associated with basically transferring those neural impulses into something that's understandable. What I mean by that is when neural activity passes from the auditory cortex to Wernicke's area, a transformation takes place. Wernicke's area is a part of the brain that basically translates the sound or the pattern of neural firing associated with the sound into actual language. There's really cool proof of this. People that have damage to Wernicke's area, it's in the back of the brain on the left side near the temporal parietal junction. But people with damage to this region, basically they have what's called

Wernicke's aphasia. And while they can hear sounds, if someone's speaking, they can't transform it into language. But what's really crazy is people with damage to Wernicke's area, they can actually still produce spoken language. They just can't understand it. Anyway, to sum up, sound comes in through the ear. It goes up the auditory nerve to the primary auditory cortex. Then those neural impulses are transferred to Wernicke's area where the transformation into language occurs. And this doesn't just involve Wernicke's area. There's activation across the brain. For instance, if I say the word hammer, then you're going to get activation in motor regions associated with grasping a hammer. Now when it comes to speech production, that's where a part of the

brain called Broca's area comes in. It works in conjunction with Wernicke's area and other parts of the brain to produce speech. And from Broca's area, basically you get motor activation in the primary motor regions and speech is produced. So that's the speech pathway. Music obviously involves the same regions of the brain. You need activity in Wernicke's area to transfer the lyrics that you hear into language that you understand. And if you're going to sing, you need activity in Broca's area. But there's other parts of the brain that are active as well. For instance, we also get a lot of right hemisphere activity when we listen to or we create music.

This is a pretty prominent finding and this is why people get into this left brain right brain thing. But you have to remember when you're listening to music or playing music or creating music you still have activity in all of the left hemisphere areas associated with speech production and understanding of speech. So the primary music areas that are activated are the same as the language areas. But you also get activity in other brain regions. For instance, you get activity in regions of the brain that are associated with empathy. And these are the emotional regions of the brain. So the amygdala, you see activation, the insular cortex, the hypothalamus are all regions of the brain that are involved in emotional processing.

And you get activity in these regions when you're listening to or making music yourself. And there's more to that as well. Scientists have found that you get releases of oxytocin when people are listening to music or singing in groups, or if you're just improvising music, and you get changes in cortisol levels in the brain that you basically decreased during listening to music and when you're singing. What's kind of cool about that is cortisol is associated with stress. So basically what I'm saying is if you listen to music or you sing, it's actually going to help you deal with stress because you get this decrease in cortisol release.

Another key part of the brain that's activated is the anterior cingulate cortex and the basal ganglia. And these regions are associated with reward processing. So our old friend, the dopamine system. While you listen to music or while you create music, you see activity in these reward centers and dopamine is released. And there's some cool bits that go with this. If you think about what we talked about last season in terms of learning and prediction errors, you'll remember that a prediction error is when something unexpected happens. So we're expecting something and something different happens. We have these prediction errors and there's a dopamine release. And when things are better than expected,

there's an increase in dopamine. And when things are worse than expected, there's a decrease in dopamine. Now this actually ties into why we like music and why we lose interest in music. So if you hear that new catchy song, it's new, it's novel, it's better than expected, and there's a dopamine release and that's why we like it. But this is also why we lose interest in music, the one hit wonders, if you will. Those prediction errors only happen for so long. When you hear the song, and it's exactly what you expected, then that dopamine release doesn't happen. And this is why we might lose interest in these sort of novel songs. But of course, some music persists. There's those songs that you love, that you've listened to your whole life.

I can think back to songs that I grew up with back in the 80s, and I still love that song. So how does that stay with us if there's no prediction error and no release of dopamine? Well, that's where those emotional brain regions come in. Those songs cause activity in the amygdala, for instance, or the insular cortex. And that emotional response is a memory, if you will. And that's why you love the music, because it creates this emotional response. So in the short term, there's this little dohumenergic release, and that's that prediction error that makes things better than expected. And that's why you love the music initially.

But if you really like the song and it stays with you, you'll get this activity in these emotional parts of the brain, and that's why you love the song for the rest of your life. There's a lot of cool research about music in the brain. Dr. Burdett, a professor at Wake Forest Baptist Medical Center in Winston-Salem, they basically put people in the MRI scanner and they were looking at fMRI scans when people were listening to their favorite song. And they found that there was activity in the default mode network. If you remember, the default mode network

is a network of brain regions that are activated sort of in the background and are the basic firing patterns of the brain. And you see increases specifically when you're doing nothing. But the default mode network is associated with self-awareness, empathy, and internal thought. And they found that listening to your favorite songs, music you really like, increases activity in the default mode network, which will help increase self-awareness, empathy, and internal thought. So basically, listening to music and even playing music that you really like because of this activity in the default mode network, it has a really positive effect on mental health. It's something that will benefit you. So I guess one of the conclusions of the neuroscience of music is listening to music will enhance work performance, especially if it's

something you like, and it'll all just make you feel great. Other research has been done looking at what happens when people create music. So the study I'm referring to was a study again using fMRI, but they were specifically looking at professional composers while they were composing music. It's kind of hard to imagine, but imagine a composer lying back in an MRI scanner and they're in there making, composing music. Well, that's what these researchers did. And basically what they found is they got decreases in activity in motor regions of the brain and decreases of activity in the occipital lobe and the postcentral cortex while they were composing. while they were composing. However, they found that there was greater activity in the anterior singular cortex, the right angular gyrus, and the superior frontal gyrus during composition. And in fact, they showed that the connectivity of these regions were enhanced. And what I mean by

that is these regions were firing more in sync together. So during composing, it's like your brain is turning off the production areas that actually would allow you to play the music. And instead, these midbrain regions and these frontal regions, which are associated with creativity and thought and allowing us to do novel things, they become more activated. And interestingly, in the same study, they saw more activity in the default mode network as well when people were creating music. And that's associated with integrating this music or composing the emotional response, if you will. Now, this week, we're going to add something new. Welcome, Matt. Matt is our producer, and he's going to tell you about another cool study about music in the brain. Take it away, Matt. Thanks, Olav. Hi, I'm Matthew, one of the graduate students in

Olav's lab and the producer of the That Neuroscience Guy podcast. Today, I wanted to help out by discussing some interesting research on what happens in our brains when we make music together. It's very common for musicians to work together to make music, whether it's a band with each member playing a different instrument, or even songwriters and producers working together to arrange a song. More often than not, music is a collaborative process. When humans work together, our brains link up in a process called interbrain neural synchrony. Basically, the brain activity in two people cooperating will be synchronized both in the

time that they're active and where in the brain their activity is. This can happen in simple settings, like completing a puzzle together, or even really complex ones, like an orchestra performing a symphony. Let me get back to music with an example. Imagine you're a classic rock band, where a guitar player might play some chords, and then another guitarist will play a riff or a solo on top of it. At first, maybe the solo guitarist will have to listen to the chords, decide what they want to play, what sounds good, and then they'll start. As it turns out, the guitarist's brains will sync up even when one of them is only listening to the other.

They don't even have to play for their brains to synchronize. However, when they do play together, the synchronization only increases. In a really interesting study done by Mueller et al. at the Max Planck Institute in Berlin, pairs of expert guitarists played jazz music together while EEG data was recorded, or brain waves. Each guitarist in the pair took turns playing a jazz melody while the other listened, and then after that, they played together. The guitarists also took turns playing the rhythm component while the other improvised a melody over that rhythm. Think of one guitar player just playing some chords, and the other guitar player playing a riff or a series of riffs that leads to one complete melody.

Results showed that as we talked about before, the guitarist's brain synced up when they listened to each other play music, and that synchronization even increased when they both played together. What's interesting here though, is that the synchronization was seen at lower brain frequencies when one guitarist was listening, and higher brain frequencies when both were playing. What this really means is that because playing together requires so much coordination and effort, our brains have to work together faster to stay on beat. However, when researchers did look at lower frequencies,

they found that the different roles, soloist or rhythm player, led to different brain areas being synced up. Basically, which brain areas sync up with your partner will depend on if you have to maintain the rhythm, or if you have to improvise melodies on the fly. This pattern of activity is actually what allows us to handle the complexities of simultaneously listening to a rhythm, while also contributing a unique melody to the song. Let's go back for a second to where I discussed how even when watching a musician, there is synchronization between brains. As it turns out, this even applies to the audience. In a study done by Dolan and colleagues in London, audience members observed

a musical performance while EEG was recorded. A chamber music band completed two versions of the same song, one where they played it as it was written, and another where they played it with a heavy dose of improvisation. Afterwards, the audience reported that they felt the improvised version was more compelling and enjoyable overall. And related to that, the synchronization of brain activity between the audience and the band was greater when the performance was improvised. activity between the audience and the band was greater when the performance was improvised. What this really means was that the inter-brain synchronization between the band and the audience actually indicated how enjoyable the performance was. This even extends to the performers themselves. To summarize, our brains sync up with each other when we play music together, and this synchronization will even change based on what role we have in making that music.

And when listening to music, the more our brains synchronize with those performing it, the more enjoyment we got out of their performance. That's it for me. I'll see you next week. But for now, back to you, Dr. K. Thanks for that, Matt. That was super interesting and super cool. Thanks for that, Matt. That was super interesting and super cool. So there you have it, music in the brain. Not surprisingly, when we listen to music, we activate our language areas, the areas that are associated with understanding language and the areas that are associated with producing language. But we also activate emotional parts of the brain. So the dopamine system, the amygdala, and the insular cortex. So the neuroscience of music is tied to reward and positivity. And of course, I mentioned the default mode network. All of these brain regions are more activated when we're listening to music, creating music, or playing music. And that's why music has such a positive impact on our mental health and our happiness in general. So that's all for today. Remember, you can follow me on Twitter at ThatNeuroscienceGuy.

You can email us at ThatNeuroscienceGuy at gmail.com. We've got our YouTube channel now with videos that are relating to different topics in neuroscience, right now with a major focus on research methods and how scientists actually do research. That's ThatNeuroscienceGuy on YouTube. And of course, there's the podcast. Thank you so much for listening. My name's Olof Kregolsen, and I'm That Neuroscience Guy on YouTube. And of course, there's the podcast. Thank you so much for listening. My name's Olive Kregolson, and I'm That Neuroscience Guy. I'll see you next week. Thank you.