The eight-circuit model of consciousness is a hypothesis by Timothy Leary, later expanded on by Robert Anton Wilson and Antero Alli, that suggests "eight periods [circuits] and twenty-four stages of neurological evolution". The eight circuits, or eight "brains" as referred by other authors, operate within the human nervous system, each corresponding to its own imprint and direct experience of reality. Leary and Alli include three stages for each circuit that details developmental points for each level of consciousness.