So, I sometimes 'proctor' tests while I"m at work.
Basically for certain things, a student will sit in a nice quiet room to take the test--I can see through the window and I make sure they don't do anything weird.
This guy has the OK from his prof to wear headphones.
So this 60ish year old guy is rocking out while doing math.
I just watched him play imaginary drums while headbanging (eyes closed and I don't think he realized anyone could see him) then open his eyes, have an 'ah-ha!' moment, and write down a math answer.
More power to him.