“The hook brings you back,” sang Blues Traveler.
“I can’t get it out of my head,” complained Electric Light Orchestra.
If either of these songs have wormed their way into your consciousness, you’re experiencing involuntary musical imagery (INMI), otherwise known as an “earworm.” Earworms are so common that some of the best-known have become Internet memes — and once you’ve caught one, they’re notoriously hard to kill.
But what makes an earworm? And can you learn to write a hook or chorus that other people can’t get out of their heads?
Here’s the science behind musical infestation.
Never Gonna Give You Up, Never Gonna Let You Down
Getting a song stuck in one’s head is a surprisingly common human experience. Researcher James Kellaris, Ph.D. estimates that 99 percent of people experience earworms, and about 50 percent say that earworms happen to them “frequently.”
And a lot of us find ourselves habitually hooked by a melody: About 25 percent of people say they experience the earworm phenomenon “several times a day,” according to Dr. Mikel Delgado.
Some types of songs are more likely to reach earworm status than others, too. Kellaris’ study found that 73.7 percent of “catchy” songs had lyrics, 18.6 percent were ad jingles and 7.7 percent were instrumental pieces. About 7.5 percent of Kellaris’ study group were plagued by a particular sensitivity to their least favorite song (and they overwhelmingly voted Billy Ray Cyrus’ “Achy Breaky Heart” into this category).
Why do earworms strike? Research indicates that exposure to a song is the No. 1 cause of its stickiness, according to Jeanette Bicknell, Ph.D. Memory triggers, like returning to a certain place or seeing a word or phrase associated with a song, can push the earworm’s play button. The brain may be more likely to mull over a tune when it’s bored or worried, as well.
While research into the earworm phenomenon is relatively recent, the phenomenon itself is well known. In the 1980s, Chicago parking garage mogul Myron Warshauer patented a system that used earworms to help people remember where they parked, says Cecil Adams, longtime columnist at The Straight Dope.
Warshauer’s system played a different popular, catchy tune on every floor. If visitors were lost, they simply had to check which song had been stuck in their heads.
Hooked on a Feelin’, I’m High On Believin’
What turns a tune into an earworm? Kellaris identifies three main features:
- Repetition. A repetitive musical phrase can get stuck more easily because once the phrase begins it’s easy for the brain to finish — just play it again. And again. And again.
- Simplicity. Anyone who remembers the intensive 1990s aggravation of having Barney the dinosaur’s “I love you, you love me” tune stuck in their head understands how simplicity makes for sinister earworms.
- Rhythmic interest. Songs like Dave Brubeck’s “Take Five” or Leonard Bernstein’s “America” (from West Side Story) may get stuck in people’s heads because the unusual rhythms cause a cognitive “itch” the brain tries to scratch by playing out the rest of the song, Kellaris says.
Further research has begun to uncover more of the secrets of catchy tunes. A 2016 study published in Psychology of Aesthetics, Creativity, and the Arts gathered 1,000 songs survey respondents had accused of being earworms then matched them with 1,000 songs that were never mentioned, but that were similar in style.
The researchers then asked the respondents what the earworm songs had that their counterparts didn’t. The answers paralleled Kellaris’ in some respects. Unusual rhythms and repetition, for instance, tended to make a song stick more effectively.
But the researchers also found that earworm-itude was also enhanced by:
- Unusual intervals. Songs like Deep Purple’s “Smoke on the Water” and Glenn Miller’s “In the Mood” tended to stick because they made uncommon interval leaps.
- Familiar shape. Songs with a rising and then falling pitch shape, like the hook to Maroon 5’s “Moves Like Jagger,” fit a pattern common in Western music (see also: “Twinkle Twinkle Little Star”).
Popularity and recency — the chances of encountering a tune frequently in your present life — also had a significant impact on what got labeled an earworm. Typically, listeners had to have heard the tune at least twice, and tunes heard more than six times were far more likely to get stuck, according to the study.
“It is also generally uncommon to experience completely novel music as INMI, although a handful of reports of self-composed music have been found in previous work,” the researchers noted.
Once an earworm is stuck in your head, getting it out can be tough. Kelly Jakubowski, one of the researchers in the 2016 study, recommends either listening to the song in its entirety, distracting yourself with another song or task or actively ignoring it.
By Now, You Shoulda Somehow Realized What You’ve Got to Do
Research indicates that the amount of variation in hit songs is shrinking.
In a 2017 piece for The Pudding, Colin Morris uses a Lempel-Ziv algorithm to demonstrate that the lyrics of popular songs are getting more repetitive. By analyzing chart-toppers from 1960 to 2015, Morris found that the most popular songs get more repetitive every single year.
Why so repetitive? Listeners’ attention spans are shorter, for one thing. On average, listeners tune in for about seven seconds before switching the radio station or skipping to the next song in their streaming app, says Roc Nation CEO and co-founder Jay Brown.
To catch their attention, says Brown, “You’ve got to have a hook in the intro, a hook in the pre[chorus], a hook in the chorus, and a hook in the bridge, too.” That’s a lot of hooking.
But just as earworm songs in general have common features, so do particularly catchy hooks. Researchers Dr. Alison Pawley and Dr. Daniel Mullensiefen analyzed the hooks of several top songs on the UK charts and discovered that the catchiest songs had several elements in common:
- Longer, more detailed musical phrases. We’re more likely to sing along if the hook’s lyrical phrase fills a breath, according to Pawley and Mullensiefen.
- More pitches in the hook. A hook that changes notes frequently is more captivating. We’re more likely to sing along until we get it right — and all that practice makes it far more likely to get that hook stuck in our heads.
- Male vocalists, particularly with higher voices and more vocal effort. The increased effort leads to more energy, while singing in the tenor range makes a hook singable for many types of voices.
Add repetition, and you’ve got the makings of a perfect earworm.
With these features in mind, it’s easy to see how a hook like the chorus of Maroon 5’s “Moves Like Jagger” became one of the top songs listed in Jakubowski et al’s 2016 study. It’s lyrically repetitive: “I’ve got the moves like Jagger, I’ve got the moves like Jagger, I’ve got the mo-o-o-o-o-o-o-o-oves like Jagger.”
At the same time, however, the hook can be sung as one long phrase in a single breath. The final “moves” covers an entire fifth’s worth of steps, but the word gets stretched into a musical scale, making it relatively simple for sing-alongs.
If You Wanna Be My Lover, You Gotta Get With My Friends
While the recipe for a more engaging hook makes sense in context, what’s not required to create a virulent earworm can be even more surprising.
Consider, for example, “Wannabe” by the Spice Girls. Widely considered to be the catchiest pop song of all time, “Wannabe” became the subject of a 2014 study by Dr. John Ashley Burgoyne and Dr. Jan van Balen, who wanted to understand: What makes this song so catchy?
The answer may be helpful to modern pop songwriters, who need to slot hooks throughout their compositions.
“We found, much to our surprise, that writing a very surprising and unusual hook is not the recipe for long term memorability,” Burgoyne told the BBC. “Actually, the more conventional your melody in terms of the interval patterns that you use; in terms of the rhythms that you use, the easier the song is to remember over the long term.”
In other words, the trick may not be originality, but innovation: Using familiar pitches and patterns in a new way.
An equally surprising study found that listeners don’t even have to like the song in order to find it catchy. For a 2011 study published in PLOS One, researchers used functional MRI (fMRI) imaging to examine participants’ brain reactions as they listened to various popular songs.
The researchers found that the brain responds with increased activity and additional dopamine production when a song is familiar to the listener. These effects don’t appear when a song is unfamiliar.
However, whether or not listener likes the song seems to have little effect. Increased brain activity and dopamine production were observed even in study participants who reported strongly disliking a familiar song. While activity in areas of the brain related to thought and speech changed based on the listener’s like or dislike, activity in the emotional centers did not.
“Familiarity seems to be a crucial factor in making the listeners emotionally engaged with music,” the study reported.
So, what’s in store for the next chart-topping earworm? While we can’t know exactly what we’re in for, we can guess: It’ll be instantly familiar — and impossible to escape.