I am prone to earworms.
No "call the vet" jokes, please. I tried already. The receptionist asked, "Is the patient a large animal?" "Many say yes," I replied over the phone.
My earworms are snippets of music. They get stuck in a loop in your head and there is no dislodging them until they choose to decamp of their own free will.
Mark Twain wrote of them in an 1876 story called A Literary Nightmare. It concerned a jingle streetcar conductors sang. It got stuck in his head for days and the only thing for it was to tell it to someone else and pass the curse.
Suffice it to say I read the story in 1962, in the collection Tom Sawyer, Detective and I have never forgotten the jingle. I am just glad I don't know the tune.
How powerful is that Twain jingle? I was separated from my copy some years ago. For Christmas, a dear Facebook friend Lynnsy Logue, said she was going to send me a holiday gift.
And when it came in the mail, it was a copy of the self-same edition of Tom Sawyer, Detective. That earworm ran me to ground.
For me, rhythmic activities summon the earworm spirits.
This was a good thing when I rowed. I sat 6 behind stroke (the middle of the VIII, the coxswain explained to me, "is where we put the big dumb ones"), and used his stroke as my metronome while running one Bach piece or another through my head. It kept me right on pace.
Now it's hiking that mostly messes with my head. Today I was out on a four-mile ramble (it was 70F out, in February you don't waste days like that), at the usual 2.5 mph, and, to keep time with my big feet, up came a tune.
Not Bach, though. A bit of doggerel I saw in an ad for tumblers bearing commonly-misheard pop song lyrics. For four long miles, over and over, my walking companion was this: