And why is it usually a song we don’t even like?
They’re called “earworms,” and they’re just catchy tunes that get stuck in your head. They’re easy, predictable, and usually very simple. The article cited Lady Gaga’s “Bad Romance,” and jokes that even if you haven’t heard it in a while, the “Rah Rah ah-ah-ah” is probably in your head now, likely even before reading the lyric (lyric, or sound? Whatever it is).
Kelly Jakubowski is a music psychologist in the UK, and she says that it’s just a few basic factors that make a song more likely to get stuck in someone’s head. The pace of the song (basically the song maintains a constant speed), the “shape” of the melody (pitch change – higher to lower, etc), and a few unique intervals (a break-down of the beat that happens at a different speed, like a mini-rap or rhyme that’s simple between choruses).
Some examples of songs that top the list of most common earworms:
-“Bad Romance,” Lady Gaga
-“Don’t Stop Believin’,” Journey
-“Somebody That I Used To Know,” Gotye
-“Bohemian Rhapsody,” Queen
Check out some more details on the phenomenon here, and a few more examples of other songs.