Is there such a thing as life after death?
While this was once a question pondered by philosophers and religious groups, scientists are now seriously considering the possibility that consciousness can continue after a person has been clinically diagnosed as dead.
A large-scale study involving 2,060 patients from 15 hospitals in the UK, USA and Austria has found that patients experience real events for up to a three-minute period after their heart has stopped beating.
Dr Sam Parnia, assistant professor of critical care medicine and director of resuscitation research at the State University of New York and a former research fellow at the University of Southampton, said it was previously thought only hallucinatory events were experienced in these circumstances.
These are normally described as out-of-body experiences (OBEs) or near-death experiences (NDEs).
The Awareness during Resuscitation (Aware) study, sponsored by the University of Southampton, used objective markers to establish whether the experiences were real or hallucinatory.
The results showed that 39% of patients who survived cardiac arrest described a perception of awareness but did not have explicit recall.
A total of 46% experienced a broad range of mental recollections, 9% had experiences compatible with NDEs and 2% exhibited full awareness compatible with OBEs with explicit recall of "seeing" and "hearing" events.
One man in particular, a 57-year-old social worker from Southampton, was reported to have given a “very credible” account of what was happening in the room during the three minutes that he was "clinically dead".
The man could describe the movements of the doctors and nurses in the room with uncanny accuracy. He told the researchers he felt he was standing in the corner of the room, observing the medical staff resuscitate him.
Dr Parnia said: "This is significant, since it has often been assumed that experiences in relation to death are likely hallucinations or illusions, occurring either before the heart stops or after the heart has been successfully restarted, but not an experience corresponding with 'real' events when the heart isn't beating.
"In this case, consciousness and awareness appeared to occur during a three-minute period when there was no heartbeat.
"This is paradoxical, since the brain typically ceases functioning within 20-30 seconds of the heart stopping and doesn't resume again until the heart has been restarted.
"Furthermore, the detailed recollections of visual awareness in this case were consistent with verified events.
"Thus, while it was not possible to absolutely prove the reality or meaning of patients' experiences and claims of awareness, (due to the very low incidence - 2% - of explicit recall of visual awareness or so called OBEs), it was impossible to disclaim them either and more work is needed in this area.
"Clearly, the recalled experience surrounding death now merits further genuine investigation without prejudice."
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The actress has described her near-death experience on several occasions, including during an interview with Larry King in 2005. An allergic reaction caused Seymour to go into anaphylactic shock. Though she told King she doesn't belong to a specific religion, Seymour said she saw light and believes "there is some spiritual entity that's greater than us." In another interview with BeliefNet, Seymour said she lives life to its fullest and tries her best to make a difference.
Since his own near-death experience in 2008, during which he was virtually brain dead for a week, academic neurosurgeon Eben Alexander has been studying the relationship between science and spirituality, the results of which are set to be published in a 2012 book. "I do not believe that there is a good neuro-physiologic explanation for what happened to me," said Alexander on an episode of "Through the Wormhole with Morgan Freeman."
Clinical psychologist Mary Jo Rapini appeared on "TODAY" in 2010 to talk about the near-death experience she had following a brain aneurysm. She is only one of the more than 1,000 patients studied by Dr. Long. In a YouTube video, Rapini said God -- who was more of a voice and had no real face or shape -- said to her: "Have you loved any person the way you've been loved in this short time here? ... You can do better."
In 1991, singer-songwriter Reynolds underwent hypothermic cardiac surgery. Once the surgery was complete, Reynolds woke and described the near death, out-of-body experience she had while unconscious. According to articles on the subject, including one published in Progress in Brain Research in 2005, Reynolds said she watched the surgery from outside her body, listened to music playing in the operating room and met with her deceased relatives. Medical professionals have argued over exactly what happened to Reynolds, such as on a 2009 National Public Radio segment. Cardiologist Michael Sabom, M.D., who researched near-death experiences (including Reynolds'), discusses her case in his book "Light and Death." Reynolds passed away in 2010.
Though he didn't have a near-death experience himself, Lommel spent significant time researching the topic, the results of which appeared in a 2001 paper published in The Lancet. On his website, Lommel describes some of the typical experiences of his research subjects. A 44-year-old man, for instance, described accurately everything that happened to him while he was brought to the hospital comatose. Others reported a disappearance of the fear of death, seeing their entire life in perspective and knowing "the thoughts of everyone involved in the event, as if I had their thoughts within me" and encounters with deceased relatives.
Research psychologist at Nottingham Trent University Dr David Wilde, is currently gathering data on out-of-body experiences in an attempt to discover a pattern.
Speaking to The Telegraph, he said: “Most studies look retrospectively, 10 or 20 years ago, but the researchers went out looking for examples and used a really large sample size, so this gives the work a lot of validity.
“There is some very good evidence here that these experiences are actually happening after people have medically died.
“We just don’t know what is going on. We are still very much in the dark about what happens when you die and hopefully this study will help shine a scientific lens onto that.”
The study was published in the journal Resuscitation.