Your taste in music is weird. Maybe you just can’t stop listening to that power ballad, or you’ve wondered about your bewildering weakness for yodeling. And maybe, just maybe, nobody understands your all-consuming obsession with Steely Dan, the greatest band of all time.
But even with all these differences, neuroscientists have noticed there’s something pretty much everyone agrees on, musically: Some chords sound good—they’re consonant—and other notes grate when they’re played at the same time. Unraveling why that is could explain something basic about how humans perceive the world. Maybe people are just wired that way. Or maybe, as a paper argues today in Nature, it’s a product of human culture.
Yes, this is a nature versus nurture debate. And it’s been raging for centuries, if not millennia. Scientists trace it back to Pythagoras, who theorized about musical intervals in the first place. Over the years, the heavyweights of science and philosophy have chimed in—Galileo, Kepler, Descartes.
Today’s scientists have their own explanations. Maybe it’s the structure of the inner ear, or the neat ratios of frequencies in harmonious chords. Or maybe dissonant chords sound dissonant because of something called roughness: If you were to simultaneously play two notes right next to each other on a piano—a C and a C-sharp, say—their sound waves would clash in a jarring, unpleasant way.
Composers and ethnomusicologists have pushed back on those physical explanations, though. Maybe people prefer those consonant thirds and fifths because so much of Western music is built on them. They’re just used to it.
The thing is, most researchers haven’t studied people without experience listening to Western music. It’s much easier to come by undergrads who grew up on Pitbull and Taylor Swift. But Josh McDermott, a cognitive scientist at MIT, managed to get access to the Tsimane, an Amazonian society with minimal exposure to Western culture. “If you ask Westerners, they’ll tell you they like consonance, and dislike dissonance,” he says. But only testing Westerners makes it hard to distinguish whether the preference is innate or cultural.
To get to the villages, McDermott had to fly to La Paz, Bolivia, take a small plane into a town at the foot of the Andes, truck down dirt roads, and finally canoe for several days. Then he played the Tsimane recordings of various chords (minor seconds, major thirds, tritones) and presented a rating scale. They found consonant chords just as enjoyable as dissonant ones. He also tested them to see how they felt about roughness, and found that they disliked it. For good measure, he asked them whether they preferred recordings of laughter over gasps to see if they understood the instructions. (They did.)
Other neuroscientists, though, think that all this talk of nature or nurture props up a false dichotomy. “Music tastes vary even within a culture, and part of the reason for that is difference in experience,” says Tecumseh Fitch, a cognitive biologist at the University of Vienna. “No one would ever doubt that.” You could find a collection of death metalheads or Jimi Hendrix fans or Schoenberg enthusiasts, he says, and they might all say they love tritones.
So culture plays a role, yes. But Fitch and other scientists point to a raft of evidence that show that a preference for consonance is innate. Babies, for example, stare longer at speakers playing consonant music than dissonant. (McDermott, for his part, doesn’t find that evidence convincing—those babies could’ve been exposed to Western music, he says, even in the few months they’d been alive.)
Or, even more fundamentally, animal studies! Fitch points to experiments that show certain species of bird prefer to sing at consonant intervals, or that baby chicks were more likely to imprint on objects making consonant sounds. And Robert Zatorre, a researcher at the Montreal Neurological Institute, notes that the neurons of macaques responded differently to dissonant chords in a column responding to the paper. “It would be hard to argue that this effect is mediated by the monkeys’ musical culture,” he writes.
This debate isn’t getting resolved anytime soon---most of the scientists said they weren’t swayed by McDermott’s study. But many of them also agreed that you can have it both ways. Maybe an innate bias for consonance exists, but that doesn’t mean every culture develops it. Instead, learning and experience ultimately determine what preferences actually play out. Which means no matter what, you can still blame your inexplicable love for '70s dad-rock on your parents---their genes and their playlists.
