Day the fifthth

Never Fear!  I have a cunning plan which can not possibly fail

Is for Ear worm.

 This is the technical term for a tune that is stuck in your head. It comes from the German, Ohrwurm, which means that if I can't think of a subject for O then I'll repeat this one in German.
I suffered from it the other day and got to thinking about it. For the record the song was the theme from True Blood. (Bad Things - Jace Everitt)
From what I've been able to deduce it is the first few seconds and the last few seconds of the song which are the important ones, because if they end the same or close ie: C D C A ...(rest of the song)... C D C A then the chances of getting the tune stuck in your head is increased by quite a large margin.

 This is because while you are consciously aware that the song has finished your brain is registers the C D C A and says to itself "Ah, the last time I heard this combination of notes that song was starting so I must be listening to it again" so the brain goes through the motions of listening to the non existent song until it comes to the end of the song again whereupon it begins the whole process again unto infinity.
 The good news is that there is a way to counter the brain skip [1]. All you need to keep another song in the back of your mind and bring it to the front when you catch yourself repeating the song in your head. I always like to listen to The Time Warp because it's a catchy tune that everybody knows and if you accidentally start singing it out loud then there's a better than average chance that anyone who hears it will start singing along[2]

 This is purely my own research but I won't be surprised if the boffins that are looking into this thing prove me right.
Ever get a tune in your head? how long did it last?

[1] It's called a mind enema
[2] Not when you're been interviewed for a job they wont.