 Good afternoon. When I started playing the guitar years ago, I would make a lot of mistakes. But the more I play, the more I start wondering who decides what sounds good and what sounds bad. I'm Karla and I'm looking for the answer. Now, raise your hand if you think that I made a mistake while I was playing. Many of you, each one of you would have a unique impression of what you heard. And you may think, how can it be that we hear something different? Music perception is different for each of us. It depends on the kind of music that you listen to, your culture, among others. I am interested in the effect of musical training. What we know about how musical training changes our brain and our perception to the day it is not clear. But I have the key for understanding it. It's our brain. After years of training, our perception changes because our brain changes. And this is precisely the aim of my thesis to understand how musical training changes our neural responses to music perception. So in music, we usually combine patterns of tension and release to create what we call harmonic expectations. These expectations, the resolution of attention is pleasing because it fulfills the expectations, but they can be broken in many ways. What if I say, people is usually surprised when a sentence does not end like they potato? The analogous or equivalent in music would be, this is an ambiguous ending that has an enjoyable degree of novelty, but what if I say, people is usually surprised when a sentence does not end like they... The analogous in music would be, this is a super dissonant ending that is unacceptable because it violates the rules of music. Now, how do you think a musician would respond to these musical surprises in comparison to a non-musician? To discover it, we invited both of them to our scary laboratory. There we use the technique of electroencephalography or EEG. This is our brain, and this is the EEG representation of it. The amount of neural activation is represented by the intensity of the color, where the blue would be the strongest. So I looked to the first milliseconds right after the musical surprises, and this is what I found. Musicians, when they hear an ambiguous ending, they showed a neural activation, and so did non-musicians, but to a lesser degree. But when musicians heard that this is an ending, they showed a much bigger and longer response, while non-musicians showed more or less the same responses before. In my first year of PhD, I've confirmed that the ability to detect musical surprises is universal, but that after training, musicians are able to distinguish between different degrees of musical violations. My research is only a starting point, but if we understand how musical training changes our brain, we could design new ways of teaching music. And musical training has many benefits, on attention, on learning new languages, and on some psychological disorders such as autism. So, the next time you hear something weird in music, don't think that it's a mistake, think that it's a surprise, because music and life are much more interesting with surprises. What do you think?