For years, I have referred to songs that got stuck in my head as "earworms." It's graphic, it's disturbing, and yes, it reminds me of that scary worm critter than Khan uses to control Chekov in The Wrath of Khan:
Called "Ceti Eels", this image gave me nightmares. Actually, it still might. At any rate.
I have a memory that seems to retain nearly everything it hears effortlessly. If by "everything" you mean "useless information, the term for forgetting nouns (nominal aphasia), and the most annoying songs on the planet." So the term "Earworm" is one I end up using quite a bit.
la, la, lalala, lala, lala, lala, lalala
If you've never searched the internet for "lyrics 'la la la la la'" before, I'm here to tell you it's not a very fruitful search. There are very many songs with refrains or long stretches of lyrics consisting only of that repeating monosyllable.
Of course, when you have an earworm, and you only remember a tiny portion of the refrain, it's almost imperative that you find the rest. So I was in a bit of a quandary. What's easier to find -- on Wikipedia at least, though the OED doesn't recognize it -- is the etymological origins of the term "earworm". The Wikipedia article helpfully provided a real source in the form of a Guardian article, so I can bring you someone else's interpretation of the term's origins.
The term "earworm" is a translation of the German word Ohrwurm, used to describe the "musical itch" of the brain. It is a confusing term, since the phenomenon has nothing to do with small maggot-like creatures crawling into your ear and laying eggs in your brain. The musical earworm actually works more like a virus, attaching itself to a host and keeping itself alive by feeding off the host's memory. Nor does the earworm occur in the ear, as researchers at Dartmouth College, New Hampshire, demonstrated in their study, Musical Imagery: Sound of Silence Activates Auditory Cortex.
What's fascinating here -- besides the fact that it's from German and has nothing to do with actual critters -- is the fact that the phenomenon is actually described similarly to what Richard Dawkins termed a "meme." Earworms are self-replicating bits of cultural information, which invade the human brain and are perfectly designed to drive you nuts.
To keep a medieval focus: I often sing with a compline group at Columbia, on Sunday nights. I'm pretty sure that monks must have gotten this little tune stuck in their heads:
Ah yes. The Psalm recitations. (composed, rather poorly and from memory, by yours truly, using Noteworthy Composer*)
So how does my earworm story end? Well, after searching fruitlessly for a few weeks, running countless Google and GoodSearch searches for endless variations on "la la la la la" lyrics, I found it. Earworm etymological origins -- check! Song from months and months ago that was rampaging, virus-like, through my dissertation-addled brain -- check!
I give you: Blur, "For Tomorrow".
It's not as happy as you'd think.