Why we can’t get a song out of our head

Washington: You must have at some point been "infected" with a song, which you just can’t shake off. Scientists have now revealed how earworms can linger on for days at a stretch in some people.

Andreane McNally-Gagnon, a PhD student at the University of Montreal Department of Psychology, said that mostly earworms would disappear after a few minutes. But, in some cases, earworms can last hours or even days.

McNally-Gagnon is also a musician, who is often infected, which is why she wanted to better understand how and why it occurs.

For starters, she asked French-speaking Internet users to rank 100 pop songs according to their ability to be compulsively repeated within one``s mind.

The top five were—Singing in the Rain (Gene Kelly), Live Is Life (Opus), Don``t Worry, Be Happy (Bobby McFerrin), I Will Survive (Gloria Gaynor) and, in first place, Ca fait rire les oiseaux by Caribbean sensation La Compagnie Creole.

In the laboratory, the researchers asked 18 musicians and 18 non-musicians to hum and record their obsessive songs and note their emotional state before and after.

The researchers found earworm infections last longer with musicians than with non-musicians.

The phenomenon occurs when subjects are usually in a positive emotional state and keeping busy with non-intellectual activities such as walking, which requires little concentration.

"Perhaps the phenomenon occurs to prevent brooding or to change moods," said Sylvie Hebert, the thesis director.

The study also revealed that auditive memory in people is can accurately replicate songs.

Humming among musicians was only one key off original recordings, while non-musicians were off by two keys.

Now, the researchers are planning to study earworms using MRI or Transcranial Magnetic Stimulation technology.

"The only such studies that have been conducted were on test subjects who mentally imagined a song. We believe the neurological process is different with earworms, because the phenomenon is involuntary," said Hebert.