I can't believe physical exhaustion is not at least as important a part in this. Personally, I skip a night's sleep every now and then to readjust my sleeping patterns, and I've never experienced anything strange after something like 32-36 hours without sleep (but note: no significant physical exertion involved).
It doesn't even feel that bad once you get past the slump in the 20-24 h region.
It doesn't even feel that bad once you get past the slump in the 20-24 h region.