popularized in the mid-20th century. He explained yoga nidra as a state of mind between wakefulness and sleep that opened deep phases of the mind, suggesting a connection with the ancient tantric practice called nyasa, whereby Sanskrit mantras are mentally placed within specific body parts, while meditating on each part (of the bodymind). The form of practice taught by Satyananda includes eight stages (internalisation, resolve (sankalpa), rotation of consciousness, breath awareness, manifestation of opposites, creative visualization, repeated resolve (sankalpa) and externalisation). Satyananda used this technique, along with suggestion, on the child who was to become his successor, Niranjanananda Saraswati, from the age of four. He claimed to have taught him several languages by this method. Satyananda's multi-stage yoga nidra technique is not found in ancient or medieval texts. However, the yoga scholars Jason Birch and Jacqueline Hargreaves note that there are analogues for several of his yoga nidra activities. Yoga nidra in this modern sense is a state in which the body is completely relaxed, and the practitioner becomes systematically and increasingly aware of the inner world by following a set of verbal instructions. This state of consciousness is different from meditation, in which concentration on a single focus is required. In yoga nidra the practitioner remains in a state of light withdrawal of the 5 senses (pratyahara) with four senses internalised, that is, withdrawn, and only hearing still connects to any instructions given. Swami Rama Swami Rama taught a form of yoga nidra (in a broad sense) which involves an exercise called shavayatra, "inner pilgrimage [through the body]", which directs the attention around "61 sacred points of the body" during relaxation in shavasana, corpse pose. A second exercise, shithali karana, is said to induce "a very deep state of relaxation", and is described as a preliminary for yoga nidra (in a narrow sense). It too is performed in shavasana, involving exhalations imagined as directed from the crown of the head to different points around the body, each repeated 5 or 10 times. The yoga nidra exercise itself involves directed breathing lying on the left side, then the right side, then in shavasana. When in shavasana, the attention is directed in turn to the eyebrow, throat, and heart centres or chakras. Richard Miller The western pioneer of yoga as therapy, Richard Miller, has developed the use of yoga nidra for rehabilitating soldiers in pain, using the Integrative Restoration (iRest) methodology.