Yoga Nidra was developed by Swami Satyananda Saraswati round about 1940 and was developed from a tantric practice of Nyasa (meaning, 'to place' or 'to take the mind to that point'). It can be practised by people of any religion or culture.
Yoga Nidra can be done alone with a tape or in a class. Generally speaking, it's more enjoyable done in a class, however this is not always available.
What is Yoga Nidra and How Does it Work?
Yoga Nidra (the term 'nidra' translates as sleep) has been called 'yogic sleep', however this is not strictly accurate. It's a state between waking and sleep, practised in a totally relaxed state - a sort of psychic or dynamic sleep. In this threshold state (this state has also been called the hypnogogic state) contact with the subconscious and unconscious dimensions can occur spontaneously. In this state, the mind is extraordinarily suggestive. The aim of the practice is to release muscular tensions, emotional tensions and mental tensions. It is said that an hour of Yoga Nidra equates to four hours of conventional sleep1.
Yoga Nidra, allows the mind to be 'impressed' because when relaxation is complete, receptivity is greater. It can not only relax, but restructure and reform the whole personality from within. The means of doing this is through the 'sankalpa', described below.
Yoga Nidra is not hypnosis. Although the sensory channels are disconnected, awareness is maintained. The brain is completely awake. Yoga Nidra stimulates the brain by heightening awareness of the body. The progressive movement of awareness through the parts of the body (described below) clears all the nerve pathways to the brain, as well as inducing physical relaxation. It relaxes the brain by relaxing the body.
The characteristic feature of Yoga Nidra is the systematic rotation of consciousness in the body, following preparation.
Yoga Nidra should be practised in a darkened (but not totally dark2) room, free from distractions and interruptions.
The body rests prone on the ground or on a thin mat, spine straight, facing upwards with palms uppermost, at a comfortable temperature. Once the practice has begun, it is important not to move the body, so it is important to prepare properly, by stretching and shifting body parts until a state of relative comfort is reached.
Usually before the practice begins, a student will choose a 'sankalpa', which is a resolve or resolution. The resolve should be short and positively phrased and is intended to reshape your personality and direction in life along positive lines. The student repeats it three times and it acts as an autosuggestion. It should not be changed until it is achieved and the exact wording should be used on each occasion.
It is not necessary to make yourself peaceful when beginning Yoga Nidra, simply to expose yourself to the instructions of the teacher and to allow yourself to view any experiences which may arise with total awareness and detachment.
Withdrawing the Mind
In Yoga Nidra, awareness is progressively withdrawn from the external world, the body, the process of breathing, the conscious mind, and finally the unconscious mind. In order to prevent consciousness from being completely withdrawn, which would result in sleep, awareness is maintained by concentrating on the auditory channel. Anyone listening to a Yoga Nidra class will undoubtedly hear snores, as this is easier said than done! A good class teacher or instructor on a tape will always give the instruction 'Do not sleep!'.
Rotation of Consciousness
Once the student is in position and has made the sankalpa, the instructor will begin by directing the consciousness to various areas of the body in strict rotation. By heightening awareness of the body, the practitioner is stimulating the brain. In this way, yoga nidra relaxes the mind by relaxing the body.
The instructor will then call out the parts of the body, 'Right hand thumb, second finger, third finger, fourth finger, fifth finger, palm of the hand, back of the hand, wrist, elbow, shoulder, armpit, right side, right waist, right thigh, kneecap, calf muscle, ankle, heel, sole, big toe, second toe, third toe, fourth toe, fifth toe', etc.
During this practice, consciousness should be light. There should be no concentration, just awareness. The instructions should be given at a speed that keeps the mind moving fast, but allows it to understand and carry out instruction as it is being given.
Teachers may take their students through other practices including counted breath, image visualisations and other practices at this stage. At the end of the practice, the mind should be brought out of its state gradually practising awareness of breath. This can include counting breaths with navel, chest, throat and nostril awareness, before asking the student to repeat the resolve. The practice finishes, with gentle movements of fingers and toes and then other stretches, before sitting up and opening the eyes.
Yoga Nidra for Children
Yoga Nidra can be practised by even small children. They can relax much more quickly than adults, although they find it difficult to remain still. Practice should be limited to 10 or 15 minutes. They respond very well to visualisation practices and counting breath practices.
Additional benefits claimed for Yoga Nidra include reductions in blood pressure and hypertension and relief of asthma and migraine headaches.
There are other associated practices, however these are beyond the scope of this entry. These can include body/floor awareness, awareness of feelings, eg cold/warm, heavy/light, pain/pleasure, chakra visualisation, etc. These are described in the links provided in this entry.