A light appeared at the end of Raymond's tunnel. He, too, was at first afraid and resisted. The light was female, and she "communicated" with him.
He surrendered to her. "I realized that I shouldn't struggle, and I let myself go. It was at that moment that the experience took place."
Scientific research on people having NDEs is tough, because the exact instant that they occur is unknown, making them nearly impossible to observe, Laureys said.
It would also be cruel to run brain scans on someone who was possibly facing the moment of death.
So, Laureys and his team studied the near-death memories of people who survived -- in particular those of coma patients -- with the help of a psychological examination.
The Memory Characteristics Questionnaire tests for sensory and emotional details of recollections and how people relive them in space and time. In other words, it gauges how present, intense and real a memory is.
They compared NDEs with other memories of intense real-life events like marriages and births, but also with memories of dreams and thoughts -- things that did not occur in physical reality.
The researchers paralleled new memories with old ones. And they compared the patients who had NDEs with groups of others who didn't.
Memories of important real-life events are more intense than those of dreams or thoughts, Laureys said.
"If you use this questionnaire ... if the memory is real, it's richer, and if the memory is recent, it's richer," he said.
The coma scientists weren't expecting what the tests revealed.
"To our surprise, NDEs were much richer than any imagined event or any real event of these coma survivors," Laureys reported.
The memories of these experiences beat all other memories, hands down, for their vivid sense of reality. "The difference was so vast," he said with a sense of astonishment.
Even if the patient had the experience a long time ago, its memory was as rich "as though it was yesterday," Laureys said.
"Sometimes, it is hard for them (the patients) to find words to explain it."
The questionnaire asks people about their level of certainty that a remembered experience was a real event and not imagined or dreamed. "They (the patients) are very convinced that it is real," Laureys said.
A simple Internet search reveals hundreds of accounts of near-death experiences -- some real, some perhaps invented. Many people are convinced they are proof positive that an afterlife exists outside of the physical realm -- and that it is wondrous.
There are reports of religious images appearing at times in NDEs, but they are not limited to one single religion, and they don't always appear. Sometimes Buddha, Jesus or Mohammed appear, but usually they don't, Laureys said.
Nevertheless, an NDE can make a convert of a skeptic. Dr. Eben Alexander is a well-known case of an agnostic scientist who became convinced of the existence of the spiritual.
He has often shared his story in television interviews with journalists and expressed his views in lectures and in books and video presentations, which he sells on his website.
Alexander, a neurosurgeon, according to his autobiography, has described his experience in the same terms as the Belgian researchers: "hyper-reality," "too real to be real."
In the beginning, he tried to interpret his experience as a brain function, he wrote on his website, but he became increasingly spiritual. He has come to the conclusion that people are reincarnated.
Alexander says his experience could not have been a hallucination, because the parts of the brain necessary to produce his experiences were basically dead when he had them.