You know when you can’t get a song out of your head? James Kellaris, a professor at the University of Cincinnati, recently studied the problem in 559 students. At the latest meeting of the Society for Consumer Psychology, he reported his findings, which are totally fascinating.

Apparently, “earworms” — songs you can’t stop humming in your brain — most often plague women and musicians. To try and dislodge the song, two-thirds of the time people will try humming a different song; 14% of the time, they try humming the song to its end. Kellaris has no idea why earworms occur. When he asked his students — whose average age was 23 — to describe the worst earworms, their top-10 list was:

1. Other. Everyone has his or her own worst earworm.
2. Chili’s “Baby Back Ribs” jingle.
3. “Who Let the Dogs Out”
4. “We Will Rock You”
5. Kit-Kat candy-bar jingle (“Gimme a Break …”)
6. “Mission Impossible” theme
7. “YMCA”
8. “Whoomp, There It Is”
9. “The Lion Sleeps Tonight”
10. “It’s a Small World After All”

I did some digging into Kellaris’ work, and it turns out he’s done some interesting research into music and psychology. Specifically, he’s studied the ways that music affects shopping:

“We’ve found that lively music can shrink shoppers’ perception of time passage, so that they think they’ve been in a store for less time than they actually have,” he says. “And the more time they spend there, of course, the more likely they are to make unplanned or impulse purchases.”

Even people put “on hold” on the telephone have thought they were waiting for a shorter time when they listened to faster tempo music, according to the marketer’s research. If relaxing (i.e., boring) music was played, clients believed their time on hold was longer than it really was. …

Human crowding is one circumstance where adjusting ambient music seems to make a difference, according to the researcher. Combine a lot of shoppers with very loud music — think “Jingle Bell Rock” during the Christmas shopping crunch — and the store will seem even more crowded than it is. But playing slow music when just a few customers are in a store also makes shoppers uncomfortable.

“We found that people evaluate a store most positively — and this is a little bit different than their perceptions of crowding — when there is either fast tempo music and not a lot of people shopping, or where there are a lot of people and slower tempo music,” the professor points out.

In The Republic, Socrates bans “music without lyrics”, because he felt that it was immoral. Music without words, he argued, could be used to subtly stir men’s passions. When you read his ideas, they sound oddly naive — until you think about muzak and its role in urging us on.