Because you like them? But is there a deeper reason. The first time you heard Taylor Swift’s “Shake it Off,” you barely noticed. Then the song made its undercover assault, seeming to play in every grocery store, on every radio, and in every TV commercial you saw — and before you realized it, you were bobbing your head to the music. Soon, you were seeking it out, playing it over and over when no one else was around. Years later, you still can’t get enough of that Taylor Swift goodness. Never mind your questions about whether this story is autobiographical; the real question is this: What makes you want to repeat some songs over and over again while other songs go stale? The answer may lie in evolution.
Evolution favors the traits that help organisms survive to have offspring, and the best way our ancestors learned to survive was by trusting what they already knew and distrusting what they had never encountered before. If you experienced something once and it didn’t kill you, chances are it won’t kill you the second time. That may be the driver behind what psychologists call the “mere exposure effect”: basically, you like things more just by being exposed to them.
But anyone who’s had the same meal five nights in a row knows that there’s something different about repetition when it comes to music. That could be because our brains process music a lot like they process language — in other words, as if it’s information. As Bruce Richman explains in “The Origins of Music,” birds, wolves, whales, and other animals mimic each other’s calls to signal that they’re part of the group. Early humans were likely no different. At some point in our evolutionary history, those nonsense noises branched off into music and language, but the two stayed closely linked.
But even if our brains consider music to be more special than tastes or sights or even noise, why is it that some songs can send your finger toward the repeat button while others just start to get annoying? That comes back to the idea of music as information. Often, the songs we listen to over and over have a certain level of complexity — think of the decades-long popularity of Queen’s “Bohemian Rhapsody,” for example. It’s layered with so many different melodies and voices that you could listen to it five times in a row and notice something different every time. The idea is that if you can keep hearing something new with every listen, you’ll keep coming back for more.
But the opposite is also true. As parent of young children can attest, you can only listen to “The Wheels on the Bus” so many times before you want to tear your hair out. The same way your brain loves learning new things, it hates wasting time with the stuff it already knows, and simple songs get old much faster than complex ones.
But complexity is only part of it —”Shake It Off” isn’t exactly Beethoven, after all. The way the music makes you feel is also very important. In 2013, a University of Michigan study found that of the songs participants liked listening to repeatedly, more than two-thirds were happy, energetic tunes that made them “pumped up” and “ready to dance.” “Bittersweet” songs that made people feel sad and wistful were also big winners, and while not as many of those songs made the cut, the participants reported relistening to them many more times in a row than the happy songs.
It’s this emotional connection that could explain why some songs don’t get stale even after years of repeated listening. As Alex Fradera writes for BPS Research Digest, “the emotional payoff is reliable, much as is a mood-regulating drug, and that reliable payoff can be more important than the hit of something novel.” And, of course, that’s really what it all comes down to. If a song makes you feel good, you’ll want to play it again, regardless of whether it’s a complex masterpiece or fluffy pop. Haters gonna hate, hate, hate, hate, hate.
Check out my related post: Are you a Walkman?