In 1968, social psychologist Robert Zajonc asked 100 college students to look at a list of antonym pairs (things like "high/low," "able/unable," and "optimism/pessimism") and asked them to choose the one in each pair that they thought had "the more favorable meaning." He then compared their results to each word's frequency in the English language. Overwhelmingly, the participants thought the more common word was the more favorable one. The phenomenon that makes you think more familiar things are more pleasant is known as the mere exposure effect, and it's a big reason music producers keep pumping out the same sounds you've heard before.

Even at the turn of the 20th century, people knew that music sounded better the more you listened to it. In 1903, Max Meyer published a report in Experimental Studies in the Psychology of Music showing that when people heard a song that was foreign to them (in this case, quarter-tone music, like the kind common to Chinese cultures), they reported liking it more after every repetition.

Of course, modern technology drives this point home even more. A 2011 fMRI study found that the emotion and reward centers of the brain were more active when subjects heard familiar music than when they heard unfamiliar music, and a 2013 study found that subjects' emotional arousal was higher after hearing a familiar song, even if the subjects didn't remember hearing it before. You might think you're an adventurous music fan, but your brain just loves the songs it knows.

Music producers know this all too well. According to The New Yorker, "A relatively small number of producers and top-liners [people who write the melodies and lyrics] create a disproportionately large share of contemporary hits, which may explain why so many of them sound similar." Just take songwriter Max Martin, for example. The Swedish 40-something is responsible for a jaw-dropping number of hits, ranging from those performed by the Backstreet Boys, 'NSync, and Britney Spears to more modern artists like Katy Perry and Taylor Swift.

The key is to mix the comfort of the familiar with a little bit of surprise. "Within the vein of all the other successful pop music, [it helps when] someone does something that's just a little bit different," music professor Clay Stevenson tells Pigeons & Planes. "So maybe they throw in a different instrument, maybe they throw in an extended bridge, or an extended part to their hook."

But there's a silver lining to all this. The fact that familiarity breeds favoritism means that with a little bit of extra work, you can easily expand your musical tastes. When you listen to something new, put it on repeat a few times. If you don't like it after a handful of listens, well, it wasn't meant to be. But if science has proven anything, you very well might find a new favorite.

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For more about how Max Martin and other songwriters formulate a smash hit, check out "Song Machine: Inside the Hit Factory" by John Seabrook. We recommend the audiobook, which is free with a trial of Audible. We handpick reading recommendations we think you may like. If you choose to make a purchase through that link, Curiosity will get a share of the sale.