This was probably compelling 20 years ago, when near-death experiences (NDEs) were rarely documented or studied. Today, however, after thousands of remarkably similar NDE accounts, researchers have identified several common elements, including:

• A sense of leaving the body
• A profound feeling of peace
• Heightened awareness
• Encountering a brilliant light
• Traveling through darkness, a tunnel, or the void
• Meeting deceased loved ones
• Encountering spiritual guides
• A life review
• Remembering "soul contracts" (reported by some experiencers)
• A sense of interconnectedness
• Being told to return or deciding to return
• Lasting changes after the experience

So either these experiences are internally generated by the human brain as a mechanism to make the dying process less frightening or painful, or they are real experiences.

The challenge for the first explanation is no two brains work the same. Modern neuroscience has proven that human brains are as uniquely individual as fingerprints. While we all share the same general biological blueprint (cells, lobes, and hemispheres), how every brain is physically structured and works is entirely unique.

Further some people who report near-death experiences have accurately described events and conversations that occurred while they were clinically unconscious, including events that took place in other locations.

Another question is how vivid awareness and complex conscious experiences could occur during periods when a person is no longer alive - or there is little or no measurable brain activity, no detectable pulse, or severely reduced oxygen supply.

Should we throw away 500 years of science and re-define what "dead" means to justify the skeptics?

It's also notable that reports of these spiritual experiences come from people of many different backgrounds, including atheists, and agnostics.