Yoga nidra
Yoga nidra or yogic sleep in modern usage is a state of consciousness between waking and sleeping, typically induced by a guided meditation.
A state called yoga nidra is mentioned in the Upanishads and the Mahabharata, while a goddess named Yoganidrā appears in the Devīmāhātmya. Yoga nidra is linked to meditation in Shaiva and Buddhist tantras, while some medieval hatha yoga texts use "yoganidra" as a synonym for the deep meditative state of samadhi. These texts however offer no precedent for the modern technique of guided meditation. That derives from 19th and 20th century Western "proprioceptive relaxation" as described by practitioners such as Annie Payson Call and Edmund Jacobson.
The modern form of the technique, pioneered by Dennis Boyes in 1973, made widely known by Satyananda Saraswati in 1976, and then by Swami Rama, Richard Miller, and others has spread worldwide. It is applied by the U.S. Army to assist soldiers' recovery from post-traumatic stress disorder. There is some scientific evidence to support yoga nidra across clinical and academic disciplines, including the neurosciences and psychology.
Historical usage
Ancient times
The Hindu epic Mahabharata, completed by the 3rd century CE, mentions a state called "yoganidra", and associates it with Lord Vishnu:The Devīmāhātmya, written around the 6th century CE, mentions a goddess whose name is Yoganidrā. The God Brahma asks Yoganidrā to wake up Vishnu to go and fight the Asuras or demigods named Madhu and Kaitabha. These early mentions do not define any yoga technique or practice, but describe the God Vishnu's transcendental sleep in between the Yugas, the cycles of the universe, and the manifestation of the goddess as sleep itself.
Medieval practices
Yoganidra is first linked to meditation in Shaiva and Buddhist tantras. In the Shaiva text Ciñcinīmatasārasamuccaya, yoganidra is called "peace beyond words"; in the Mahāmāyātantra it is named as a state in which perfected Buddhas may access secret knowledge. In the 11th or 12th century, yoganidra is first used in Hatha yoga and Raja yoga texts as a synonym for samadhi, a deep state of meditative consciousness where the yogi no longer thinks, moves, or breathes. The Amanaska asserts that "Just as someone who has suddenly arisen from sleep becomes aware of sense objects, so the yogi wakes up from that at the end of his yogic sleep."By the 14th century, the Yogatārāvalī gives a more detailed description, stating that yoganidra "removes all thought of the world of multiplicity" in the advanced yogi who has completely uprooted his "network of Karma". He then enters the "fourth state", namely turiya or samadhi, beyond the usual states of waking, dreaming, and deep sleep, "that special thoughtless sleep, which consists of consciousness." The 15th century Haṭha Yoga Pradīpikā goes further, stating that "One should practice Khecarī Mudrā until one is asleep in yoga. For one who has achieved Yoganidrā, death never occurs." Khecarī Mudrā is the Hatha yoga practice of folding the tongue back so that it reaches inside the nasal cavity, where it can enable the yogi to reach samadhi. In the 17th century Haṭha Ratnāvalī, Yoganidrasana is first described. It is an asana or yoga pose where the legs are wrapped around the back of the neck. The text says that the yogi should sleep in this position, which "bestows bliss". These texts view yoganidra as a state, not a practice in itself.
Modern usage
Western "relaxationism"
The yoga scholar Mark Singleton states that while relaxation is a primary feature of modern Western yoga, its relaxation techniques "have no precedent in the pre-modern yoga tradition", but derive mostly from 19th and 20th century Western "proprioceptive relaxation". This prescriptive approach was described by authors such as the "relaxationist" Annie Payson Call in her 1891 book Power through Repose, and the Chicago psychiatrist Edmund Jacobson, the creator of progressive muscle relaxation and biofeedback, in his 1934 book You Must Relax!.Dennis Boyes
In 1973, French yoga advocate Dennis Boyes published his book Le Yoga du sommeil éveillé; méthode de relaxation, yoga nidra. This is the first known usage of "yoga nidra" in a modern sense. In the book, Boyes makes use of relaxation techniques including the direction of attention to each part of the body:The French journal Revue 3e Millénaire, reviewing Boyes's approach in 1984, wrote that Boyes proposes relaxation in order to "reach the state of emptiness". The person thus imperceptibly moves to a stage where relaxation becomes meditation and can remain there once the mind's obsession with external objects or thoughts is removed.
Satyananda
In modern times, Satyananda Saraswati claimed to have experienced yoga nidra when he was living with his guru Sivananda Saraswati in Rishikesh. In 1976, he constructed a system of relaxation through guided meditation, which he 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. The form of practice taught by Satyananda includes eight stages, rotation of consciousness, breath awareness, manifestation of opposites, creative visualization, repeated resolve. Satyananda used this technique, along with the suggestion, on the child who was to become his successor, Niranjanananda Saraswati, from age four. He claimed to have been taught 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.
| Order | Satyananda | Earlier practices | Notes |
| 1. | Preparation | Savasana, lying down, was used in Laya yoga in Dattātreyayogaśāstra. | It was a meditation technique, not a preparatory stage. |
| 2. | Resolve / Sankalpa | Sankalpa was intentional thinking. | Medieval texts like Amanaska sought to rid the mind of Sankalpa, not to use it. Satyananda was probably following Western relaxation therapies. |
| 3. | Rotation of consciousness | Nyāsa is described in Mahānirvānatantra and other tantras. | Sir John Woodroffe's translation says one should say mantras in turn over six parts of the body. Satyananda could have built up his practice starting from this. The 14th century Yogayājñavalkya describes an 18-point body scan for pratyāhāra but there is no evidence Satyananda knew of this. |
| 4. | Awareness of breath | ——— | The 13th century Vivekamārtaṇḍa names the sounds of inbreath and outbreath, implying awareness of breath. |
| 5. | Feelings and sensations | The 14th century Yogabīja calls yoga "the union of the multitude of opposites". | It is unclear whether Satyananda made use of medieval texts for this activity. The texts speak of transcending opposites, whereas he uses them in meditation. |
| 6. | Creative visualisation | Visualisations were the characteristic feature of tantric yoga, with dhyāna using complex images of a deity. | Satyananda uses other images, such as the cross or golden egg, but his process of concentration, meditation and absorption is like that in yoga texts. |
| 7. | Repeated resolve / Sankalpa, ending | Intentional thinking, as in item | Satyananda repeats the Resolve stage and then gradually brings the mind back to wakefulness. |
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 with four senses internalised, that is, withdrawn, and only hearing still connects to any instructions given.