Kay Jamison discusses the experience of mania.
Well mania, is just like depression - it is different in different people. And it can range from very mild periods of just feeling elated and full of energy and not needing much sleep, to a full blown psychosis where people hallucinate, see things that aren't there, hear things that aren't there, are paranoid and delusional and are as mad as you will ever see or hear anyone. I mean, it is an incredibly psychotic state in its most extreme forms, and obviously the term "raving maniac" comes from mania, I mean, it is, in its worst forms, as disturbed as you get. But in the milder forms there's a kind of a period of time on the way up where people can feel quite extraordinary, they can feel highly productive, feel wonderful, you feel full of life and vital, everything seems and feels and you hear everything different. You see things differently, you experience things differently, everything is much more intense and marvelous.