Pumpkin Princess Pat here:
I don’t believe it’s headline-making news that writers are essentially ADD-impaired thinkers. (See Mary Jo’s blog prior to this for examples!) One thought leads to another, which leads to another, which leads to looking up a reference, which leads to two dozen more books, and then to note-taking and before we know it, voila, there’s a book in there somewhere.
Ah, that I could limit my attention-deprived mind to simply reading books. Alas, it also becomes 
distracted by many, many other things, like ear worms--songs, jingles, and tunes that get stuck inside my head. (cartoon to the right courtesy of bonbell.stumbleupon.com) Do you have any idea how difficult it is to write a straight sentence with “YMCA” kicking and grinding through my poor, worm-eaten brain cells? I have written an entire book on the basis of a single ear worm that wouldn’t leave me alone. I wrote another more recent one—SMALL TOWN 
GIRL—that just spilled lines from songs across the page because I was writing about music. My subconscious is so blighted with ear worms that any phrase can generate a line from some old rock or folk song. Who hasn’t had “We Will Rock You” pounding in their head after accidentally colliding with it in radioland or elsewhere?
You will note the use of a quote from AA Milne’s James James Morrison Morrsion in a previous blog. That did not come because I have memorized Milne. I couldn’t memorize my phone number if you threatened me. But the poem has been set to music and sung by Chad Mitchell and weaves through my mind like a cold in my nose. I’m likely to sneeze it out at any irritation. I mean, who can resist a line like “King John put up a notice: LOST or STOLEN or STRAYED! JAMES JAMES MORRISON'S MOTHER SEEMS TO HAVE BEEN MISLAID.” The whole song just begs to be chanted (loudly) at the drop of a pun. Did I mention how distracting this is when I’m trying to write my own words? (King John said he was sorry…)
I know this plague of bad music sticks in my head for a reason, so—naturally—I went in search of the reason instead of working on the book in progress. The term ear worm apparently appears in a scientific study summarized at WebMD which acknowledges that these snippets get stuck in the minds of women and obsessives more than others. Everything gets blamed on estrogen, doesn’t it? Has to be hormones because I don’t have enough memory left to be remember an obsession. My memory cells are eaten out by ear worms. 
And so, of course, marketing latched onto this very lucrative penchant of ours with catchy jingles that we sing in our sleep. But not only that, they can time the type of music to the type of crowd to keep you shopping. For more, try this 2003 blog http://www.collisiondetection.net/mt/archives/000299.html . After reading the comments there, I’m thinking I need a copy of Hawaii 50’s theme song to blast these worms right out of my head.
For me, Simon and Garfunkle’s “My Little Town” is the ultimate ear worm. I have no idea why, but I had it in my head for an entire year. Even though my S&G collection is sacred ground, I was tempted to smash it into toxic dust if it would have rid my brain of that miserable little number. And just when it would start slip, sliding away, my husband would play it again. He’s too handy to have around to stomp into toxic dust, but there were times….
Any of you got ear worms? Theories on why they move in? Or how to get them out? (Don’t ever go down to the end of the town…)