Yoga Nidra, or yogic sleep, is a technique used to edge between states of wakefulness and sleep. It is induced by a guided meditation that typically includes breathwork, body scanning, visualization, guided Imagery, and intention (sankulpa) setting. This practice is mentioned in the Upanishads  and the Mahabharata. 

Modern uses of the technique are for managing blood pressure, potentially improving immune functioning, inducing deeper sleep, and reducing anxiety and stress. Yoga nidra can also be used for psychedelic preparation and integration. 

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