An academic neurosurgeon has opened up about the "life-changing" near-death experience he claims to have had while in a deep coma following a rare bacterial infection in his brain.
In 2008, De Eben Alexander, 68, told The Sun he had been skeptical that an afterlife could exist believing that when we die out consciousness dies with us.
But after his near-death experience, he has since experienced a "180-degree flip" claiming he saw heaven with his own eyes, describing it more real than the realm we currently inhabit.
"I basically used to have a very conventional, scientific and reductive materialist view that consciousness was created by the brain, and that only the physical world exists," Alexander said.
"And what my coma journey showed me … is that consciousness is something that is fundamental in the universe and does not originate in the brain.
"What I experienced was the most extraordinary, memorable, detailed, and ultra-real experience of my entire life.
"In fact, the world we live in, this material world, is more kind of cloudy and dreamlike than what I saw on the other side.
"That world is sharp, crisp and alive – and very real."
How did Alexander get to a deep coma state? In November 2008, he suffered severe pains in his back and the "worst headache of his life".
He thought it was the flu but a few hours later his wife found him convulsing in his bed with his eyes rolling to the back of his head.
He was taken to hospital and it was discovered he contracted an incredibly rare and aggressive kind of E. coli meningoencephalitis – a type of bacterial meningitis – and within hours the virus began gnawing away at his brain.
Alexander was put into an induced coma and placed on a ventilator with his chances of survival dropped by the hour.
According to Alexander, his medical records showed that his brain was "very badly damaged" with not only the neocortex ravaged by the virus, but his brain stem – which controls core bodily functions such as breathing and heart rate – was also in "deep trouble".
At best, doctors gave Alexander a 10 per cent chance of survival. That number would shrink to just 2 per cent over the next few days.
Doctors warned his family if he did survive he'd likely need care for the rest of his life.
Looking back, he says his spirit had traveled to another realm where he was experiencing a "rebirth".
Speaking about the new realm he claims to have found, he says he believed he was somewhere underground and found himself inside a primitive mucky Jell-o-like substance.
He had no sense of self, nor any memories from his life before this point, but found himself surrounded by black roots. Nothing was in focus and he couldn't speak.
"People think going through this experience, in this state of almost amnesia, must've been very horrific," he told The Sun, "and yet, I knew nothing else as a possibility, and therefore, to me, it all just seemed natural.
"This was existence. There was nothing foreboding about it, at least in that first passage.
"Then I went up through a gate, towards a great bright orb."
The light opened up absorbing him and played heavenly music, saying he felt like he was being transported to a lush land where "waterfalls flowed into crystal pools".
In his book, Proof Of Heaven, he said there were plush marshmallow-like clouds of pink and white, and the land was populated with tall trees, sweeping valleys, and groups of joyous people dancing in harmony wearing peasant clothing.
He also said he saw other people there, including women with blue eyes who didn't communicate with him physically but telepathically said: "You are loved. You are cherished. There is nothing you can do wrong."
But within an instant, he exited the afterlife and was transported back to darkness. All he could see was a bright, pulsating light that he says he understood to be the "all-loving creator" at the centre of existence.
He described being at one with the divine presence. Then he became aware of another realm, the realm he had left behind.
Alexander claims to have seen five faces emerge from the darkness and present themselves to him, and, although he didn't recognise them, he said he could sense their concern for him.
Then he woke up, defying the odds of almost certain death.
He woke up with no memory of who he was or who those around him were. He suffered ICU psychosis including nightmares and hallucinations.
"Those memories of that kind of psychotic nightmare disappeared within a week or two, compared to memories of the deep coma experience, which was sharp, crisp, vivid, alive and detailed today, as if the whole thing just happened.
"As more than half of people who've had an NDE will tell you, it's a much more real existence than this existence in the material world."
More than two weeks later he regained full function of his brain.
The four people around his bedside, he'd realise, were his family members – and four of those faces he'd seen in his NDE (near-death experience) before reawaking.
"Those first days and week or two were very frightening because my brain was still horribly affected by this illness, which makes it all the more remarkable that I ended up having such a complete recovery," he said.
"But in truth, I would say this experience was the greatest blessing of my entire life.
"It's been a tremendous gift to me to go through this experience, and then go through the 13 years since then, working with other scientists and experts around the world, to make better sense of the way this universe works.
"I look at it all as just extremely positive."
Can life after death be proven? One of the issues is because near-death experiences happen with limited warning it's nearly impossible to test.
Statistics show they're most common in patients who survive severe head trauma or cardiac arrest.
In the US, an estimated 9 million people have reported having an NDE, a 2011 study in Annals of the New York Academy of Sciences found.
Alexander believes NDEs may help to unlock the mysteries of human consciousness – and the possibility that it may continue to live on even after our bodies die.
He says he believes his own NDE is proof that consciousness exists separately from the human brain.
He said after studying his own medical charts, he came to the conclusion he was in such a deep coma during his NDE, and his brain was so completely shut down, that the only way to explain what he experienced was that his soul had detached from his body and ventured to another world – a world he believes to be Heaven, The Sun reported.
"In the 13 years since my coma, other scientists have shown me that consciousness is something that is fundamental in the universe and is not created solely by the brain, as materialist scientists believe," he said.
"The brain is still very important. I believe it serves as a filter that allows certain states of primordial consciousness, but to believe that our conscious awareness is fully derived from the brain is erroneous."
Alexander added: "This experience changed me completely.
"For most NDErs, they come back and they have absolutely no fear of death. And it's actually such a liberation, to be freed from the shackles of the prison of the physical body and brain that dominates so much of the living in this world.
"It's completely shifted my world view … when I first woke up back in this world I said, 'All is well, all is well.'
"What I've come to realise is that as long as we're aware, and paying attention to the universe and our role in it, and we're taking charge of directing that in a favourable direction that reflects love and compassion, and kindness and mercy, and kind of this beautiful connection, we share it with one mind, then all is truly well and that is something that is within all of our power – no matter what kind of travesties of the universe is going through."