From Perception to Pleasure: How Music Changes the Brain | Dr. Robert Zatorre | TEDxHECMontréal

So today's topic is about change and I want to tell you how

music

changes

the

brain

and also a personal story about how it changed my

brain

. I'm going to start with that and I want to tell you about when I was a teenager and, like a lot of teenagers, I was listening to the

music

that all my friends were listening to, which was, you know, mediocre rock and roll music, and one day, somehow, I came into possession of a record album, this is what a vinyl record looks like for those of you who are not familiar with it and this is music by Béla Bartók, the Hungarian composer who died in 1945.

I had never heard of Bela Bartok . I had no idea what he was. Actually, I put it randomly. I turned it on just to see what it sounded like and this is what I heard so I still get chills when I hear this and back then when I was 13 I experienced this epiphany. I had never heard anything like that. I had chills. I got goosebumps down my spine, I felt an incredible feeling that I couldn't really explain and then it really changed me in the sense that it gave me a focus on something that I really needed to pursue and so I decided at that moment. that I would try to understand more about music I would try to learn about music I would try to learn to play music and that maybe I would also try to apply science to music because I was already quite interested in science and I was already training as a scientist, so I tried to put these things together.

Now, the experience that I had, of course, is one that many of you have probably had and it's actually a very common thing in our species, so humans have been enjoying music for a long time, so This flute, for example, that you see here dates back to the Upper Paleolithic period, about 35 to 40 thousand years ago, and this particular specimen was found in a cave in the Danube Valley and what is now part of Germany. The remarkable thing is that at that time this part all of Europe was under glaciers, so life was not easy at that time for these people who were making these remarkable musical instruments, so they must have felt a tremendous power of music to dedicate energy, resources and time to the creation of musical instruments.

It must have been extremely important in some sense to their survival that they even carried out these activities when survival was so difficult, otherwise how is it possible? What are the brain systems that allow us to create music to perform? instruments to perceive musical patterns and experience the

pleasure

of them well, we know quite a bit about this in recent years in many laboratories around the world and also in mine, we have been trying to dissect some of these neural pathways and this diagram tells you a little bit about some of the important circuits that are involved in connecting different parts of the brain, particularly those that involve sound

perception

and the motor system for sound production, and here you can take a closer look.

The colored areas represent the portions of the brain that are dedicated to the

perception

of sounds, this is known as the auditory cortex and then there are connections that go from there to other regions, particularly those that involve the control of the motor system, so you have a sort of a loop between the auditory and motor systems that allows us to perceive and produce music and one point I want to make is that when you train in music you basically tune these circuits to a remarkable degree in this video that I'm going to show you in a second. which is courtesy of my colleague Marcelo.

Wonder what you will see is the path of movement of a violin bow as the violinist plays, then there is a sensor at the tip of the bow and as the violinist is playing, you will see the patterns that he creates and I want you to pay attention to the precision with the These patterns are displayed so you can see that the movements completely overlap each other in a quite beautiful way. Look at those loops. look how they are perfectly superimposed on each other look at this figure of eight while we play on two Springs your shape is the figure of eight sometimes I think we should forget about the lecture and listen to the rest of the Game and we would be very happy then what allows this level of precision?

How can you train your brain to be so precise? One thing that is interesting is that musical training can actually change your brain structure and this was predicted by Santiago Ramón y Cajal, who won. He was awarded the Nobel Prize in Medicine and Physiology in 1906 and in 1904 he predicted the idea that the brain could physically change through training, so he specifically mentioned the idea of ​​musical training. He said that the ability of a pianist requires many years of mental training and physical practice and to fully understand this phenomenon we have to admit the formation of new pathways and the progressive growth of nerve terminals, so he had the idea that the anatomy of the Brain could actually be changed through training and this concept was just a hypothesis at the time.

I didn't have any direct evidence of this, but in our laboratory and others we have been able to show that there are indeed some of these anatomical

changes

, so what you see here are the two halves of the brain, the two left and right hemispheres. and the colored areas represent areas where the thickness of the cortex is actually greater in people who have received musical training compared to a control group that has no musical training and the areas that distinguish these groups are not surprisingly the auditory areas that I'm showing you earlier, as well as the motor cortex and, more importantly, areas of the frontal cortex that are involved in many types of higher-order cognitive functions, including executive functions such as planning or anticipation or the ability to create to pay attention to new events that are emerging.

An important detail about this type of result is that it is linked to the age at which you start training, so we see in this image the blue region is an area of ​​the frontal cortex, but its degree of change is linked to age to which the person started training with music, so the earlier you start, the more changes you will have and this is very important because it speaks to the plasticity of the brain, which is greater at younger ages than at later ages and you may remember that I said which I was about 13 when I had that experience with music and so I'm one of those blue dots there, so my frontal cortex is not that developed, which is why I'm here giving you a lecture on science and not, you know, playing . an instrument that is perhaps what I would do if I had started early enough.

Now all of this that I have been talking to you about has to do with the ability to perceive and produce music, but really what I would like to tell you is about how we experience

pleasure

with music and to achieve this we have to go to a very different system. of the brain, so everything I've been talking about so far is in the cortex, which is the outer part of the brain, now we have to delve into the deep structures and there is a particular structural structure known as the striatum that is especially important in the representation of pleasurable experiences and this was discovered many years ago, so, for example, if you take a laboratory rat and give it food and measure the activity in its brain you will see that in this area known as the stratum the dopamine neurons will be more They activate when animals receive food, so this is basically a kind of chemical signal within the nervous system that says, "Okay, this is really it." Well, what you're getting now is really important.

You should try to get more if you can and it's not just in lab rats that we can see in healthy human participants as well, so if you put people in a brain scanning machine. and you give them monetary rewards, so you play some kind of gambling game, for example, or you give them food rewards or you expose them to erotic images, you'll see a very similar response in this deep structure known as the striatum, which is what illustrates this slide. so there is a common activity in this that we call the reward system the stimuli that are essentially essential for survival, so you need food, the opposites survive, you need sex for the species to survive, for reproduction and monetary rewards, you need them only to the extent that money is fungible right so that you can exchange it for something of value and then we wonder if it could be that music involves the same biological system even though it is not a substance, by the way, you also get these answers to drugs, but music is not a chemical substance. substance, is not strictly necessary for survival and, in fact, we have been able to show that in a series of experiments the stratum is very consistently shown to be active - very pleasant music, we have seen it with blood flow when we measure blood flow in In the brain we see it with dopamine receptors, so when we measure dopamine uptake while people listen to pleasurable music, we see an increase in the stratum and we can also see it with functional magnetic resonance imaging that measures oxygen in the blood and there again we see this.

The last study is quite interesting because what we were doing there was looking at how much value people assigned to music, so in this experiment people were exposed to pieces of music they had not heard before and asked to decide if they wanted to. listen to them. buy it or not, and if they did, they had to deposit a certain amount of money so it's kind of like iTunes, where you listen to a little more music and then you decide that you want to buy it and you can pay different amounts so that the way you The way the experiment plays out is like this, you might hear the first sample, well, okay, maybe we'll give it $0.99.

Now comes the next sample. I don't really care, I think I'll give it a zero chance. For the next one, this is a wonderful thing, maybe I'll give you a dollar twenty-nine, so in the experiment what we do is we use the amount of money as an estimate of the value to that individual of that particular piece of music and then we look at the brain what is happening with our functional imaging device and what we see is not just that the reward system is active; In other words, there is more response in this region that we call stratum, the more money you are willing to give. but also and very importantly, the reward system increases its communication with the auditory cortex the more value is assigned to it.

In other words, those regions that I talked about before that have to do with perception are more strongly coupled with the regions that have to do with perception. with excitement and reward the more you like something the more you like music and this basically links these two brain systems on the left side we have these cortical systems which are actually the most phylogenetically advanced parts of our brain. parts of our brain that distinguish us from other species, including other primates, to a greater degree than any other region and all of these cortical areas have to do with the perception of sounds and the ability to plan for the future, which means that when you listen to music develops, you are not only able to perceive sounds but you also have an expectation about what the next sound will be and the musician or composer will play with those expectations so that they are fulfilled to a greater or lesser extent, that's all.

We are very cognitive, but on the other hand we have this interaction with what is one of the most phylogenetically important parts of our brain, which are these deep structures in the reward system that we share with many other animals, so music represents a species of fusion. If you will, of these two systems, the most advanced cognitive system with the most powerful emotion and reward systems and this is basically the idea that I want to leave you with is that music has great power to engage us and make us feel emotions. and changing our brains and the way we think about it is that it derives this power precisely because it combines these two very important systems in our brain and that I think is the message that I want to leave you and I also think about the idea that by combining science and art we can get a deeper understanding in the two domains, which are not two separate domains that should really be merged and I think if we want to think about change, we want to think about how we can bring science and art together.

Thank you very much, but is it okay?