Yoga-nidra

Yoga nidra (Sanskrit: योग निद्रा) or yogic sleep is a state of consciousness between waking and sleeping, like the "going-to-sleep" stage. It 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 (yoga nidra) is the essence of meditation. When the body relaxes, the mind relaxes, and meditation happens naturally. The yogic goal is to bring this state of heightened brain wave activity into everyday life, in essence, creating a meditation of each present moment.

Yoga nidra is among the deepest possible states of relaxation while still maintaining full consciousness. In lucid dreaming, one is only, or mainly, cognizant of the dream environment, and has little or no awareness of one's actual environment.

The practice of yoga relaxation has been found to reduce tension and anxiety. The autonomic symptoms of high anxiety such as headache, giddiness, chest pain, palpitations, sweating and abdominal pain respond well. It has been used to help soldiers from war cope with posttraumatic stress disorder (PTSD).

Yoga nidra refers to the conscious awareness of the deep sleep state, referred to as prajna in Mandukya Upanishad.

The concept of yoga nidra is very ancient in Indian traditions such as Hinduism and Buddhism. Krishna is often associated with yoga nidra in the epic Mahabharata. Similarly, many yogis and rishis are supposed to have experienced yoga nidra throughout their life.

In modern times, yoga nidra was experienced by Satyananda Saraswati when he was living with his guru Sivananda Saraswati in Rishikesh. He began studying the tantric scriptures and, after practice, constructed a system of relaxation, which he began popularizing 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, sankalpa, rotation of consciousness, breath awareness, manifestation of opposites, creative visualization, sankalpa and externalisation).

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