Mark Gagnon

some type of tunnel, seeing a bright light, feeling overwhelmed by peace, meeting deceased relatives, sometimes observing their own resuscitation from above.

The cross-cultural consistency is also striking.

A Buddhist in Thailand and a Christian in Ohio and a secular or atheist person in Sweden all describe structurally similar experiences.

And the scientific explanations include many things.

oxygen deprivation triggering hallucinations, the release of endorphins, and the random firing of neurons as the brain shuts down.

DMT release during death is often cited, but hasn't been conclusively demonstrated in humans.

But a lot of people believe that when you die, you actually release some type of psychedelic drug like DMT that you actually hallucinate.

Now, these explanations account for some of the features, right?

The tunnel, the light, the euphoria.

But researchers point to cases where patients claim to describe events that occurred while they were clinically dead.

So this would include, like, conversations in other rooms, details about their resuscitation, things like that.

And these reports are compelling, but very hard to verify rigorously.

Memory is reconstructive, and it's difficult to confirm what a patient perceived versus what they pieced together afterward.

So, in 2014...

Researchers did the AWARE study, and they tried to test this by placing hidden images on shelves that could only be seen from above.

The results were inconclusive.

Too few cardiac arrest survivors could be interviewed, and the study did not find reproducible evidence of perception during cardiac arrests.

Most neuroscientists think brain physiology can explain the core features of a near-death experience, but a small minority argue that there are enough reports to challenge a purely brain-based account.

Either way, as of now, the evidence for perception during clinical death is not strong enough to overturn the mainstream view.

It's really intriguing, but it's not perfectly conclusive.