Picture this… you turn on the radio and hear a ridiculously catchy song. You know the one. An hour later, it’s still in your head – and you can’t get it out!
Certain factors can make a song an “earworm” – a memorable piece of music or sound that stays in the listener’s head well after hearing it.
Earworms tend to lodge themselves into the brain’s auditory cortex, a group of researchers from Dartmouth College found. The auditory cortex is where much of the brain’s sound processing happens, and also where musical memory is stored.
The scientists did an experiment where they conducted brain scans of people listening to familiar songs – and then interrupted the songs. The scans showed that the auditory cortex stayed active after the music stopped, imagining the rest of the song.
The same fragment of the song can get stuck in the ‘phonological loop’, which is a system of memory that constantly and temporarily stores sound information. Earworms are typically 12 to 30 seconds long, and usually well-known to the listener.
If you’re a songwriter or in a band, you might have a special interest in what makes a song an earworm – to write one of your own!
The team found that there are five components to an earworm – surprise, predictability, rhythmic repetition, melodic potency and receptiveness. They even worked out a formula to calculate the earworm potency of a song!
The formula is receptiveness + (predictability-surprise) + (melodic potency) + (rhythmic repetition x1.5) = earworm.
BONUS: Need to get rid of an earworm? Try engaging your brain in a different task like solving a puzzle or an anagram, or sing a commonly known song like “Happy Birthday” or “Twinkle, Twinkle Little Star”.