The conscious sleep practice known as ‘Yoga Nidra’ has long fascinated people with its promise of improving mental and physical health. Now, Indian researchers have explored these effects by scanning brains with functional magnetic resonance imaging (fMRI) technology to understand its value better. Researchers from IIT Delhi, AIIMS Delhi, and Mahajan Imaging Delhi have conducted this study, which was published in the international journal Scientific Reports, exploring the neural mechanisms underlying ‘Yoga Nidra’. The study shows how ‘Yoga Nidra’ practice brings deep relaxation and increased awareness. It also shows that more significant brain changes occur during ‘Yoga Nidra’ practice in individuals with greater experience in yoga/meditation.

According to a release by the Indian Institute of Technology Delhi, the study, titled “Functional connectivity changes in meditators and novices during ‘Yoga Nidra’ practice,” included two groups: 30 meditators (householders with an average of 3000 hours of experience in meditation and/or yogic practices) and 31 matched novice controls. The study found that the Default Mode Network behaves differently (less connected) in experienced meditators compared to novices. This difference in brain communication patterns helps us understand how ‘Yoga Nidra’ modulates our brain functions, promoting a state of deep relaxation while staying aware.

The study found a strong link between the amount of meditation and yoga practice participants had and the reduction in DMN connectivity during ‘Yoga Nidra’. In other words, the more hours participants spent practicing meditation and yoga, the more noticeable the changes in their brain activity during ‘Yoga Nidra’. These results could potentially indicate that experienced meditators have reduced mind-wandering as compared to novices, leading to changes in the DMN connectivity.

The researchers behind this study say ‘Yoga Nidra’ (YN) practice, a meditative technique originating from the ancient Indian tradition, has garnered global attention for its potential to improve psychological well-being and health. Despite the growing interest in its clinical applications, a comprehensive understanding of the underlying neural correlates of YN remains largely unexplored.

“Literally translated as “Yogic Sleep Practice,” ‘Yoga Nidra’ practice is typically attempted in Shavasana, a supine position resembling the stillness of a corpse, which contrasts it from other conventional meditation practices that require a seated, upright posture, thus making it suitable for MRI-based scanning approaches,” the study authors said.

As the researchers involved in this project have found, “Yoga Nidra practice employs audio-guided instructions that systematically guide the awareness of the participant to different parts of the body, breathing, or mantras that aim to induce a deeply relaxed state, mirroring the serenity experienced during deep sleep but with conscious awareness in contrast to the self-regulated focus typically associated with focused attention styles of meditations.”

The practitioner remains in a state of light withdrawal of the five senses (pratyahara) with four of their senses internalised and only the hearing still connects to the instructions. The exceptional allure of this technique stems not merely from the deep relaxation and mindful awareness it provides but also as a method to progressively master entering the most profound states of meditation (samadhi).