CAMBRIDGE, Mass. — Have you ever had a song stuck in your head and wondered why it happens? Well, scientists may finally have an answer. Researchers from MIT and the Max Planck Institute for Empirical Aesthetics have unveiled that the human brain has a universal tendency to gravitate towards rhythms made of simple, whole number ratios, such as the evenly spaced beats in a 1:1:1 ratio.
However, the specifics of these rhythms can significantly vary across different cultures, shedding light on the intricate relationship between our neurological makeup and the diverse world of music.
The study involved 39 participant groups from 15 countries, delving into how people from various cultures perceive and produce rhythms. This marks a pioneering step in understanding music’s universal aspects and its variations worldwide.
“Our study provides the clearest evidence yet for some degree of universality in music perception and cognition, in the sense that every single group of participants that was tested exhibits biases for integer ratios,” says study lead author Nori Jacoby, a former MIT postdoc who is now a research group leader at the Max Planck Institute for Empirical Aesthetics, in a university release. “It also provides a glimpse of the variation that can occur across cultures, which can be quite substantial.”
Researchers theorize that the brain’s inclination towards simple ratios might serve as a natural error-correction mechanism, helping maintain musical consistency across human societies. Music often acts as a vehicle for transmitting information, and this innate bias could help correct minor performance errors, ensuring the music’s integrity over time.
This extensive study, which builds on a smaller analysis conducted in 2017, compared rhythm perception across a broad spectrum of societies, including those with traditional music patterns distinct from Western musical norms. To gather this wide-ranging data, the team collaborated with scientists from over two dozen institutions worldwide.
Participants were asked to tap back a series of randomly generated beats they heard, a process that gradually revealed their internal biases towards certain rhythms. This method allowed researchers to map out the “priors,” or the implicit expectations for rhythms that people carry in their heads.
The findings showed that while a bias for simple integer ratios is a universal trait, the preferred ratios varied significantly among different cultures. For instance, people from North America and Western Europe showed similar biases, likely due to exposure to similar music types. In contrast, participants from Turkey, Mali, Bulgaria, and Botswana preferred different rhythms, reflective of their unique musical cultures.
These results underscore the brain’s role in music perception and production, suggesting that we mentally adjust what we hear to fit our expectations.
“When you hear somebody playing something and they have errors in their performance, you’re going to mentally correct for those by mapping them onto where you implicitly think they ought to be,” notes study senior author Josh McDermott, an associate professor of brain and cognitive sciences at MIT and a member of MIT’s McGovern Institute for Brain Research and Center for Brains, Minds, and Machines. “If you didn’t have something like this, and you just faithfully represented what you heard, these errors might propagate and make it much harder to maintain a musical system.”
By examining how different cultures perceive and produce rhythms, the study opens new avenues for exploring music’s universal and culture-specific aspects.
The study is published in the journal Nature Human Behaviour.
“.. the team collaborated with scientists from over two dozen institutions worldwide. ..” I bet that was expensive, but you have to be ‘on-hand’ to ensure that they get it right.
PS we need (a lot) more money to study this further so I can get my PhD.