Abstract
Parker calls for rigorous sleep-science collaboration on yoga nidra — distinguishing preparatory relaxation from verified deep-rest brain states.
Stephen Parker (2017). Sleep and Vigilance, 1(2), 57–63. DOI
Key findings
- State vs technique — Yoga-nidra is a brain state (delta-rich, awareness maintained), not any single script guarantee.
- Evidence gap — Many studies measure subjective calm without polysomnography or EEG confirmation.
- Sleep parallel — Benefits plausibly overlap ordinary sleep physiology — parasympathetic restoration, not magic hour replacement.
- Collaboration agenda — Sleep medicine and contemplative research need shared protocols before dose claims harden.
Limits
Narrative review — not a meta-analysis; quality varies sharply across cited yoga-nidra trials.
Application
When you try NSDR — log calm and next-hour focus; treat sleep-hour replacement claims as unverified. See Non-Sleep Deep Rest (NSDR).