First, because the brain's blood supply comes from underneath, the brain "tends to die from the top down, claiming our most human characteristics first," Dr Cameron said.
"Our sense of self, our sense of humour, our ability to think ahead - that stuff all goes within the first 10 to 20 seconds. Then, as the wave of blood-starved brain cells spread out, our memories and language centres short out, until we're left with just a core."
He said there is likely a light at the end of the tunnel, but that the "out of body experience" is not real.
CAN YOU HAVE AN OUT-OF-BODY EXPERIENCE?
No, turns out your out-of-body experience during a near-death incident is all a lie.
"I had a neuroscience instructor who had an out-of-body, near-death experience," Dr Shaw told VICE.
"They were trying to revive him and he witnessed that as a disconnected person.
"He was brought back and described that circumstance to others, this is what I saw, but basically everything he said, none of that actually happened.
"The brain can create a visual world around you that resembles something close to reality that isn't reality, because you're actually blind."
IS THERE REALLY A LIGHT AT THE END OF THE TUNNEL?
Yes. There is a light at the end of the tunnel but it may not be what you think.
Is it God? Well, Dr Shaw will leave that up to people's own interpretations, but he has quite a scientific reason why it happens.
"We know from experience tunnel vision emerges abruptly when you suddenly lose blood supply to the brain," Dr Shaw said.
"The first thing you notice in fainting is the narrowing of vision, followed by blackness.
You could argue that's the way in which death would progress as well because the same mechanisms are in place and it's an interruption of blood flow to the brain."
DOES YOUR LIFE FLASH BEFORE YOUR EYES?
Yes. We've heard our lives will flash before our eyes when we're on the brink of death and new research has found it is the last thing we think about before we die.
Researchers from Hadassah University in Jerusalem examined seven different people who had near-death experiences and discovered the flashbacks many people saw right before death were highly intense moments in their lives.
It's not like in Hollywood films, where the flashback starts at birth, then cuts to you on a swing, then your wedding day. It's not in chronological order and people who saw their lives flash before their eyes actually felt they had been taken to an alternate universe.
"There is not a linear progression, there is a lack of time limits," a person who was once on the brink of death told researchers.
"It was like being there for centuries. I was not in time or space. A moment, and a thousand years ... both and neither. It all happened at once, or some experiences within my near-death experience were going on at the same time as others, though my human mind separated them into different events."
Another person had a different experience but still saw flashbacks of friends and family.
They said they could go into each person individually and see and feel the pain they had in their lives.
"I was allowed to see that part of them and feel for myself what they felt."