What is ‘sushupti’? Inside the state of deep, dreamless sleep

Lucid dreaming is so yesterday.

Now, sleep scientists are focusing on a rare phenomenon in which people remain aware while sleeping — but experience no dreams, thoughts or even a sense of self.

Cracking this “unusual” sleep stage, researchers say, could turn everything we thought we knew about consciousness upside down.

While Western science is just now catching up to so-called “objectless sleep experiences,” Eastern cultures have been describing them for centuries.

In Hindu philosophy, it’s called “sushupti” — a deep, dreamless sleep where ego, personal identity, and the outside world fade away, leaving only a pure awareness of existence.

Often seen as a state of pure bliss, it’s free from grief, suffering, desire or worldly worries, with many reporting feelings of joy and rejuvenation upon waking.

To better understand the phenomenon, University of Edinburgh scientists turned to the internet.

 “We first surveyed 573 people online about unusual forms of sleep experiences,” Adriana Alcaraz-Sanchez, lead author of the study, wrote in The Conversation. 

Then, they dug deeper with in-depth interviews of 18 participants who said they’d had some form of an “objectless sleep experience” in the past.

All of them reported having moments during sleep with no sensory content — just a clear feeling of knowing they were aware.

Some described a faint presence in a hazy state, or an eerie awareness of “nothingness” or a “void,” where their sense of self seemed to vanish.

“Although objectless sleep experiences like conscious sleep have mainly been linked to contemplative practices, such as dream yoga, our results indicate that people without knowledge of those practices also experienced this phenomenon,” Alcaraz-Sanchez noted.

Pushing the envelope, the researchers taught four volunteers a mix of meditation, visualization and lucid dreaming tricks so that they could stay aware while drifting off.

Once asleep, the participants signaled their awareness with a pre-agreed eye movement while their brains were monitored with an EEG test.

The team found these “objectless sleep experiences” happen, at least part of the time, during deep, non-REM sleep.

“The existence of this state pushes us to reconsider what consciousness is,” Alcaraz-Sanchez wrote.

She pointed out that Western science has long pegged consciousness as awareness of an object — like your coffee cup, the color of your shoes or even your breath.

But in these rare sleep states, all those things fall away.

In the past, Alcaraz-Sanchez said sleep consciousness has mostly been studied through dreams and dream-like states — but objectless sleep experience hints at a whole new level of awareness without any content.

“The fact people can be aware of ‘nothing’ while asleep might tell us more about the mind than any dream ever could,” she wrote.