By 1968, the U.S. government had outlawed the use of LSD, so Grof and his wife, Christina, sought a therapy with the same hallucinatory and healing effects that wouldn’t get them thrown in jail. They discovered heavy breathing. The Grofs’ technique was essentially Tummo cranked up to 11. It involved lying on a floor in a dark room, with loud music playing, breathing as hard and quickly as you could for up to three hours. Willingly breathing to the point of exhaustion, they found, could place patients in a state of stress where they could access subconscious and unconscious thoughts.
