I took my verbal final exam in my Logic and Reasoning, and both my Eastern Philosophy and Western Philosophy classes baked out of my mind.
Although, since I had the same teacher for all three classes... and I know damn well that she smoked before class each day...
I find that I am able to get through the cloudy things that I have a hard time putting my finger on thought process wise alot easier. I also get the same feeling if I have been up for a long period of time occasionally.