" The rejuvenating effects of sleep are due to man’s temporary unawareness of body and breathing. The sleeping man becomes a yogi; each night he unconsciously performs the yogic rite of releasing himself from bodily identification, and of merging the life force with healing currents in the main brain region and in the six subdynamos of his spinal centres. Unknowingly, the sleeper is thus recharged by the cosmic energy that sustains all life. "

― Paramahansa Yogananda , Autobiography of a Yogi