"Kriya Yoga is Self-Realization Fellowship's flagship meditation technique, which is claimed to speed up the evolution of man's consciousness. One has to p*** through a series of other lesser meditation techniques before they can receive initiation into Kriya. These meditations incorporate thought reform techniques.

One of the early practices that the student is taught is the Hong-Sau meditation technique (in which oxygen deprivation is used), where the student repeats a mind-numbing mantra and is encouraged to decrease their oxygen intake with the ideal state to be obtained being breathlessness. Yogananda dispels the fears of the prac***ioner by claiming that the prana (life force energy) will directly feed the cells of the body, forgoing the need for oxygen.

The Aum Meditation technique is then taught after Hong Sau in which sensory deprivation is used. The eyelids and ears are held tightly sealed with the fingers while chanting a mantra and trying to listen to a mystical vibratory sound.

With all the meditation techniques, the symbol of the cult is visualized constantly and is taught to be considered as the prac***ioner's "Third Eye". This symbol represents the teachings of the cult and keeps the ideology on the prac***ioners' mind while they practice sensory and oxygen derivation techniques that break down one's critical thinking abilities.
(rick ross.com)

Ummm, let's see. Decrease oxygen to the brain and get in touch with God - yeah, that will work.