Taking a vacation day from work in order to sit in a cafe to study provided a great deal of dissonance for me.
I can't really explain the music other than that I was tired. Then again, I was a "guitar enthusiast" (but not quite a head-banger) in high school. My iPod still shows evidence of this fact.
But, just like high school, a million years ago, I'm still cramming for exams. The only difference is that the tests in high school actually held significance and meaning.