This happens if you take deliriant drugs too. You will begin to think you are in another place, in completely different circumstances, it's like being in a dream... but awake. Not like a lucid dream either, but literally just becoming delirious. This has always led me to believe that dreaming is a form of delirium. I guess by definition, it kind of has to be. You believe things that are not true, you see and hear things that are not there, and you are unable to logically reason.