Millions of people around the world claim to have inhabited a 'grey zone' between living and dying. Photo / Getty Images
Millions of people around the world claim to have inhabited a 'grey zone' between living and dying. Photo / Getty Images
Near-death experiences, in which people see a tunnel of light, or experience the strange sensation of floating above their bodies, have long been relegated to the realm of fringe science.
Now, according to an international team of researchers, it is time for the phenomenon to be taken seriously, not least because medicine is bringing more people back from the dead than ever before.
Experts from universities including New York, King's College London, Harvard, California and Southampton have published the first-ever consensus statement, setting out a standard definition for near-death experiences, and guidelines for how to study such episodes.
They estimate that millions of people around the world have inhabited a "grey zone" between living and dying in which they have experienced "a specific narrative arc" involving separation from the body, a sense of travel to a place that feels like home, and a meaningful review of their life.
"People from all over the world who have come close to death report unique transcendent experiences, but these accounts are often poo-pooed as weird anecdotes or something triggered by the brain shutting down," said lead author Dr Sam Parnia, director of critical care and resuscitation research at NYU Grossman School of Medicine.
"There hasn't been a single common definition for what people experience, and the term 'near-death experience' has been used interchangeably to refer to dreams or drug-induced hallucinations when it is something entirely different.
"We took hundreds of people's experiences and merged them together so that we could pull out clusters of experiences and come up with a common definition."
The team has proposed changing the terminology for near-death experiences to "Recalled Experience of Death"- or RED - and has set out six components to judge whether a claim is authentic.
To qualify, the experience must be; linked to death, involve a loss of consciousness, bring a sense of transcendence, be somewhat indescribable, bring a positive transformation, and be free of other coma-related experiences, such as dreams and delirium.
The new guidelines aim to separate REDs from other phenomena, such as post-intensive care syndrome (PICS), where people in a coma report dreams or wake briefly without realising and misrecall events happening around them.
Dr Parnia said soon-to-be published research will show that around 15 per cent of people who have been resuscitated from a coma after cardiac arrest have a Recalled Experience of Death.
Many people remember leaving their body but still being aware of "self". Some report being able to see in all directions, or hovering in space, sometimes connected to their own body by a cord.
Others recall being drawn through a tunnel or seeing their entire life in review, including how their actions impacted others.
Near death experiences are now being taken seriously by scientists. Photo / Getty Images
The researchers argue that such experiences share common, universal themes and are entirely different from haphazard dreams, hallucinations, or illusions. People often wake up profoundly changed, no longer fearing death and determined to live a better life.
Dr Parnia added: "These are life-changing experiences for people, but currently both doctors and patients are embarrassed to talk about them. One of my patients found that neither his doctor nor his priest wanted to discuss the experience.
"As we learn to bring more people back from the brink of death, the numbers having these experiences are likely to increase, and they are so profound for people that we need to start talking about them and studying them properly.
"Death is so fundamental to everything we do that it's important to take an objective look in an unbiased and fully scientific way about what it means."
Until the 1960s, when doctors learned that hearts could be restarted, it was considered impossible to explore death. Now, advances in science are not only finding new ways to bring people back from the dead, but are able to monitor what is happening in the body and brain during clinical death.
Studies are increasingly showing that neither physical nor mental processes stop immediately with clinical death, but instead, can carry on for hours or even longer, potentially providing a window for life-changing altered states of awareness.
In 2019, Yale University used a cocktail of chemicals to revive the brains of pigs which had been slaughtered nearly four hours earlier.
Spikes of electrical activity and gamma waves associated with heightened states of consciousness have also been recorded at the point of death.
Although the authors of the new consensus statement and guidelines say it has not been possible to prove the reality of patients' claims, they argue it has been impossible to disprove them either.
Writing in the new paper, which was published in the Annals of the New York Academy of Sciences, the authors state: "While understanding death and what happens when we die remains a mystery, this may now be a mystery that is amenable to unbiased and objective scientific scrutiny."
