Overview: Music can evoke a range of emotions and help us better understand different cultures. But what makes us tune into some songs more than others? Researchers say that when we listen to a song, our brain predicts what happens next, and that prediction determines whether we like that song or not.
Source: The conversation
A few years ago, Spotify published an online interactive map of music tastes, sorted by city. At the time, Jeanne Added predominated in Paris and Nantes, and London was favored by local hip-hop duo Krept and Kronan. It is well known that taste in music varies over time, by region and even by social group.
However, most brains are similar at birth, so what happens in them that causes us to end up with such diverse tastes in music?
Emotions – a story of prediction
If someone presents you with an unfamiliar melody and it suddenly stops, you could sing the note you think fits best. Professional musicians at least! In a study published in the Journal of Neuroscience in September 2021, we show that similar prediction mechanisms are happening in the brain every time we listen to music, without necessarily being aware of it.
Those predictions are generated in the auditory cortex and merged with the note that was actually heard, resulting in a “prediction error”. We used this prediction error as a kind of neural score to measure how well the brain could predict the next note in a melody.
As early as 1956, the American composer and musicologist Leonard Meyer theorized that emotion in music can be aroused by a sense of satisfaction or frustration arising from the listener’s expectations. Since then, academic advances have helped identify a link between musical expectations and other more complex feelings.
For example, participants in one study were able to remember tone sequences much better if they could first accurately predict the notes in them.
Now basic emotions (e.g. joy, sadness or annoyance) can be broken down into two fundamental dimensions, valence and psychological activation, which measure how positive an emotion is (for example, sadness vs. joy) and how exciting it is (boredom vs. anger), respectively. By combining the two, we can define these basic emotions.
Two studies from 2013 and 2018 showed that when participants were asked to rank these two dimensions on a sliding scale, there was a clear relationship between prediction error and emotion. For example, in those studies, musical notes that were less accurately predicted led to emotions with greater psychological activation.
In the history of cognitive neuroscience, pleasure has often been associated with the reward system, particularly with regard to learning processes. Studies have shown that there are certain dopaminergic neurons that respond to prediction errors.
Among other things, this process enables us to get to know and predict the world around us. It is not yet clear whether fun drives learning or vice versa, but the two processes are undoubtedly linked. This also applies to music.
When we listen to music, the greatest pleasure comes from events predicted with only a moderate degree of accuracy. In other words, events that are too simple and predictable – or events that are too complex – do not necessarily lead to new learning and thus only generate a small amount of pleasure.
Most of the fun comes from the events that fall in between — which are complex enough to spark interest, but consistent enough with our predictions to form a pattern.
Predictions depend on our culture
Yet our prediction of musical events remains inexorably tied to our musical upbringing. To investigate this phenomenon, a group of researchers met with the Sámi people, who inhabit the region stretching between the northernmost reaches of Sweden and Russia’s Kola Peninsula. Their traditional singing, known as joikdiffers greatly from Western tonal music due to its limited exposure to Western culture.
For a study published in 2000, musicians from Sámi regions, Finland and the rest of Europe (the latter coming from several countries unfamiliar with joik singing) were asked to listen to fragments of joiks they had never heard before. had heard before. They were then asked to sing the next note in the song, which was intentionally left out.
Interestingly, the distribution of data varied widely between groups; not all participants gave the same answer, but certain notes were more common than others within each group.
Those who most accurately predicted the next note in the song were the Sámi musicians, followed by the Finnish musicians, who had more exposure to Sámi music than those from elsewhere in Europe.
Learning new cultures through passive exposure
This brings us to the question of how we learn about cultures, a process known as enculturation. For example, music time can be divided in different ways. Western musical traditions generally use four-time signatures (as often heard in classic rock and roll) or three-time signatures (as heard in waltzes).
However, other cultures use what Western music theory calls a asymmetrical meter. Balkan music, for example, is known for asymmetrical meters such as nine- or seven-measure signatures.
To explore these differences, a 2005 study looked at folk tunes with symmetrical or asymmetrical meters.
In each, beats were added or removed at a specific time — something called an “accident” — and then participants of different ages listened to them. Regardless of whether the piece had a symmetrical or asymmetrical meter, babies six months or younger listened for the same amount of time.
However, 12-month-olds spent significantly more time looking at the screen when the “accidents” were introduced in the symmetrical gauges compared to the asymmetrical gauges.
From this we could deduce that the subjects were more surprised by an accident in a symmetrical meter, because they interpreted it as a disturbance of a known pattern.
To test this hypothesis, the researchers had a CD of Balkan music (with asymmetrical meters) played at the babies’ homes. The experiment was repeated after a week of listening, and the infants spent the same amount of time looking at the screen when the accidents were introduced, regardless of whether the meter was symmetrical or asymmetrical.
This means that by passively listening to the Balkan music, they were able to build an internal representation of the musical metric, which allowed them to predict the pattern and detect mishaps in both meter types.
A 2010 study found a strikingly similar effect in adults – in this case not for rhythm but for pitch. These experiments show that passive exposure to music can help us learn the specific musical patterns of a given culture – formally known as the process of enculturation.
In this article, we’ve seen how listening to music passively can change the way we predict musical patterns when we’re presented with a new piece. We also looked at the myriad ways listeners predict such patterns depending on their culture and how this distorts perception by making them feel pleasure and emotions differently. While more research is needed, these studies have opened new avenues to understanding why there is such diversity in our tastes in music.
What we now know is that our musical culture (that is, the music we have listened to all our lives) distorts our perception and causes us to prefer certain pieces over others, either through similarity or in contrast to pieces we already own heard.
About this news about music and neuroscience research
Author: Guilhem Marion
Source: The conversation
Contact: Guilhem Marion – The Conversation
Image: The image is in the public domain