Lots of people are fascinated by accounts of near death experiences. For example, Proof of Heaven, in which neurosurgeon Eben Alexander writes of visiting the afterlife during a near death experience, was a New York Times bestseller and sold over 2 million copies.
Reports of near death experiences (NDEs) recounted by patients who have been resuscitated (usually from a heart attack) are proliferating not only n the popular literature, but in the scientific literature too. According to The Independent, a 4-year long study overseen by emergency medicine physician Sam Parnia found:
There is scientific evidence to suggest that life can continue after death, according to the largest ever medical study carried out on the subject.
Among 2060 CA [cardiac arrest] events, 140 survivors completed stage 1 interviews, while 101 of 140 patients completed stage 2 interviews. 46% had memories with 7 major cognitive themes: fear; animals/plants; bright light; violence/persecution; deja-vu; family; recalling events post-CA and 9% had NDEs, while 2% described awareness with explicit recall of 'seeing' and 'hearing' actual events related to their resuscitation. One had a verifiable period of conscious awareness during which time cerebral function was not expected.
CA survivors commonly experience a broad range of cognitive themes, with 2% exhibiting full awareness. This supports other recent studies that have indicated consciousness may be present despite clinically undetectable consciousness. This together with fearful experiences may contribute to PTSD and other cognitive deficits post CA.
Parnia has long been fascinated with NDEs and has published before on the subject. In the journal Medical Hypotheses, Parnia's 2007 article, "Do reports of consciousness during cardiac arrest hold the key to discovering the nature of consciousness?" speculated:
Should it be demonstrated that human consciousness can continue to function when there is a lack of brain activity, this would support the theory that human consciousness may be a subtle type of undiscovered matter that is similar to electromagnetic phenomena.
Mysterious, as-yet-undetected electromagnetic-like phenomena? Back in 1907 Massachusetts physician Duncan MacDougall reported that his experiments on dying people had found that a human soul weighed about 21 grams.
Naturally, researchers with more physicalist views have offered alternative hypotheses to account for NDEs. For example, a 2011 article by British researchers in Trends in Cognitive Sciences evaluated NDEs and concluded:
Contrary to popular belief, research suggests that there is nothing paranormal about these experiences. Instead, near-death experiences are the manifestation of normal brain function gone awry, during a traumatic, and sometimes harmless, event.
One prospective study of cardiac arrest NDEs found that the experiences correlated with higher levels of carbon dioxide and potassium in a patient's blood. Another study using EEGs found that electrical activity spiked in brains suffering from oxygen loss which might then induce NDEs.
As one of my philosophy professors noted: "I have never experienced a mind that was not in close proximity to a brain." That goes for me, too.
Finally, never forget that other motives might be behind selling people hope for a life after death. Several of Alexander's colleagues now call his account into question, claiming that he fabricated at least some of the medical details in Proof of Heaven.