Yoga Nidra has been known for thousands of years by sages and yogis. Of the three states of consciousness of waking, dreaming and deep sleep, as expounded in the scriptures, Yoga Nidra refers to the conscious awareness of the deep sleep state.
There is evidence that yoga nidra helps relieve stress. An ancient technique from India, it has now spread worldwide and is also being applied by the US Army to assist soldiers to recover from post-traumatic stress disorder.
Yoga nidra 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.
Courtesy – Bihar school of Yoga