Dave Hogan / MTV via Getty Images

Redfoo of LMFAO knows exactly what it takes to get a song permanently stuck in your head. Now, researchers are getting a clue, too.

When I take my early morning spinning classes, my weary brain is in a vulnerable state. Maybe that's one reason why the chorus of a particular tune, like LMFAO's "Party Rock Anthem" or Katy Perry's "Firework," played during the workout gets trapped inside my head for the rest of the day -- and night -- and the next day. 

Known as earworms, these random snippets of songs or melodies pop into our minds repeating themselves again and again like a broken record. For me, another one was that silly jingle from the McDonald's filet-of-fish commercial, which undoubtedly would delight advertisers but I found both amusing and mildly annoying.

So it helps to know that earworms are an incredibly common experience: Studies suggest that 90 percent of people get them at least once a week. Over the last decade, researchers have spent time collecting data to learn who gets earworms, how often they occur, how long they last and which songs won't budge from our brains.

Now, a new British study in the journal Psychology of Music has tried to understand their origins. They looked at how earworms, which psychologists call involuntary musical imagery, get started in the first place.

Researchers collected data from 604 people who completed an online survey. After analyzing the responses, they identified four main triggers for earworms. The most common one was music exposure, either recently hearing a tune or repeatedly hearing it. A second reason was memory triggers, meaning that seeing a particular person or word, hearing a specific beat, or being in a certain situation reminds you of a song.

The third reason for earworms your emotional frame of mind, or "affective states."  Feeling stressed, surprised or happy when you hear a song may make it stick in your head. And a fourth cause was "low attention states."  A wandering mind, whether from daydreaming or dreams at night, can set off this involuntary musical imagery. 

"I was initially surprised by the sheer number of idiosyncrasies within the earworm surveys -- the number of different tunes people heard and the number of unique circumstances where earworms popped up," says study author, Victoria Williamson, a music psychologist at Goldsmiths, University of London.

But it makes sense, she says, since "these spontaneous mental tunes appear to be a typical everyday consequence of the way that our brains process music."

And these "sticky songs" can be a tune you hear often or a brand new one. "Earworms are likely to be as individual as we are in both our musical tastes and music listening habits," explains Williamson.

Asked what to do when you get one, Williamson says she'll be trying to find out how people control them in her next research project." But in the meantime, she offers up this advice: "I find that occupying my mind with a task helps -- reading a book, doing a puzzle or talking to a friend."

What about you? Tell us what song has stuck in your head recently and what may have triggered it. 

Related:

• Song stuck in your head? You've got an earworm
• 'Come on, Irene'? Why we mishear song lyrics
• Blinded by the lyric? Study reveals why we get the words wrong

Want more weird health news? Find The Body Odd on Facebook.

Daniel Boczarski / Getty Images

We get it, Kanye West. You think you're the bee's knees. (In the photo, West is performing in Austin, Texas, during VEVO Presents: G.O.O.D. Music.)

On iPods everywhere, Rihanna is demanding, "Want you to make me feel like I'm the only girl in the world!" Taylor Swift is whining, "Why can't you see? You belong with me!" And Kanye West is bragging, "Excuse me? Was you saying something? Uh uh. You can't tell me nothing."

It would seem that the popular music we listen to today has become more "me"-centric, less "we"-centric, when compared to hits from decades past -- at least, that's what a team of finger-wagging psychologists are saying in a new study analyzing the lyrics pop hits from 1980 to 2007. What's more, they argue that the increase in "me me me" lyrics reflect a nationwide increase in that 21st century affliction: narcissism.

"Music and culture share a powerful relationship with each other that ... has been left unexplored," write the researchers, led by C. Nathan DeWall of the University of Kentucky. (The study was published in the March issue of the journal Psychology of Aesthetics, Creativity, and the Arts.) The researchers add that "music serves as a cultural product that documents change in U.S. culture across time."

Researchers used a text analysis program to examine song lyrics for the 10 most popular songs (according to the Billboard Hot 100 year-end chart) for every year from 1980 to 2007. They found that the decades-old songs were more likely to use more first-person plural pronouns (we, our, us), while the newer lyrics contained more first-person singular pronouns (me, my, mine).

But modern songs aren't just more "me"-focused -- they're also meaner, the study shows. Researchers saw an increase in angry, antisocial words in pop songs as the years went on -- words like kill, hate, annoyed, damn, and f---. (Incidentally, two hit songs in recent months drop the f-bomb in their titles: Pink's "F---in' Perfect" and Cee-Lo's "F--- You.")

Of course, it's not entirely fair to say that pop songs reflect nationwide narcissism -- after all, what about the kids who only listen to indie or punk bands, or grown-ups who stick to oldies? Another shortcoming: The report acknowledges that the program used to analyze the lyrics isn't able to detect sarcasm or hidden meaning. Still, the researchers point out a past study that showed self-reported feelings of loneliness jumped 250 percent from 1985 and 2004 -- plus, more of us than ever are living alone, according to U.S. Census data. But it's an interesting examination of how pop culture is intertwined with our emotional lives.

Bottom line: We're not sure how, but we're pretty sure this is the fault of Facebook and Twitter.

What are some recent pop songs that are very "me me me"? And can you think of any lyrics from songs in the past few decades that defy this finding?

You can find The Body Odd on Facebook, and follow Melissa Dahl @melissadahl.

Want more weird health news? Find The Body Odd on Facebook.