Psychiatrist Bruce Greyson has spent decades talking to people about near-death experiences. His work raises questions about what happens when we die, and how we ought to choose to live

When Gregg Nome was 24 years old, he slipped into the churn beneath a waterfall and began to drown, his body pummelled against the sandy riverbed. What he saw there surprised him. Suddenly, his vision filled with crystal-clear scenes from his childhood, events he had mostly forgotten, and then moments from early adulthood. The memories, if that’s what they were, were vivid and crisp. Was he reliving them? Not quite. They came at high speed, almost all at once, in a wave. And yet he could process each one individually. In fact, he was able to perceive everything around him: the rush of the water, the sandy bed, all of it brilliantly distinct. He could “hear and see as never before,” he recalled later. And, despite being trapped underwater, he felt calm and at ease. He remembered thinking that prior to this moment his senses must have been dulled somehow, because only now could he fully understand the world, perhaps even the true meaning of the universe. Eventually, the imagery faded. Next, “There was only darkness,” he said, “and a feeling of a short pause, like something was about to happen.”

Nome recounted this story at a support group in Connecticut, in 1985, four years after the experience. He had survived, but now he hoped to understand why, during a moment of extreme mortal crisis, his mind had behaved the way it did. The meeting had been organised by Bruce Greyson, now a professor emeritus in psychiatry at the University of Virginia. (Some of the group’s members had responded to an ad Greyson placed in a local newspaper.) As Nome spoke, Greyson sat in a circle of 30 or so others, as if at an AA meeting, listening intently, nodding along.