Spiritual Meaning:
Mania suggests behaviour that is without reason, and previously was thought to be a visitation by the Gods or spirits. In dreams such behaviour is a warning of spiritual overload.
Psychological / Emotional Perspective:
Manic behaviour, such as hyperactivity, in dreams suggests that the emotions are having a bad effect on us and causing us to be out of control.
Everyday Material Aspects:
In dreams, a maniac is a personalization of that destructive part of our personality that is not properly under control.

Consult the entry for Emotions for further information.