Leads to confusion, inertia, drowsiness, blank staring, unresponsiveness, nonsensical gibberings, numbness of the senses, difficulty in forming or grasping simple thoughts and concepts and immobilisation of the body.
Commonly a result of overindulgence in intoxicants of various forms, lack of sleep and/or workaholism.
Person one: Heya, how're you today?
Person one: Whats up? Are you ok?
Sufferer: uhhh errrr brainache... meh
If you try look at the back of your neck for about 15 seconds you will experience one.
They are fucking annoying.
15 seconds later
Brain Ache! Fuck that feels annoying!