Yoga Nidra is a technique of conscious progressive relaxation of the body leading to profound meditative states. This technique can be used as a stress buster, to enhance creativity and learning, as a form of therapy and much more.This book by Swami Satyananda Saraswati from the reputed Bihar School of Yoga Publication gives a detailed description of the technique, both theory and practice. It also includes accounts of scientific investigation into the subject.
Ideally Yoga Nidra is practised as the instructions are played out from a recording, or with the help of a friend. It also includes sections on awakening of the chakras (energy centres in the astral body of an individual) and Yoga Nidra for children.
The technique of Yoga Nidra as presented in the book is an adaptation of the traditional tantric practice of Nyasa. Nyasa means ''to place''. Each part of the body is mentally felt or experienced, it''s name recited and a mantra specific to that part is ''placed'' through visualisation or touch. It is designed to invoke the deity associated with that part. In the method described in the book, the practitioner rotates his awareness rapidly through all parts of the body while simultaneously trying to visualise or recite it''s name. This is done in a specific sequence and it''s important to maintain this same sequence all the time.
This method induces complete physical and mental relaxation and can be immediately felt, although the real benefits of this practice are way down the line in the future, with continued practice. Serious long term practitioners use it for spiritual achievements.