- NEW YORK (Reuters
Health) - While no one is sure exactly what they are or why they occur,
``near-death'' experiences may not be explainable by science alone, according
to researchers.
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- Their study of 62 patients who said they had a near-death
experience after going into cardiac arrest found that factors such as medication
and the duration of unconsciousness did not explain the phenomenon.
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- ``Our results show that medical factors cannot account
for occurrence of near-death experiences,'' Dr. Pim van Lommel and colleagues
from the Netherlands report in the December 15th issue of The Lancet.
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- A small number of people who survive life-threatening
circumstances like cardiac arrest report having had ``an extraordinary
experience,'' note van Lommel, of Hospital Rijnstate in Arnhem, and his
colleagues. These so-called near-death experiences often involve visions
of a light or a deceased relative, flashbacks of life events or an ''out-of-body''
sensation.
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- Researchers have come up with a number of explanations
for these experiences. Some believe that brain cells dying from a lack
of oxygen help trigger the episodes, while others point to psychological
factors such as fear of death, or to the changing state of consciousness
people may go through in a life-threatening condition.
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- But research on near-death experiences has typically
asked survivors to recount the events long after they occurred, according
to van Lommel's team. The investigators tried to overcome this problem
by interviewing cardiac-arrest survivors within days of being resuscitated
and again 2 and 8 years later.
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- In the initial interviews, 62 of 344 survivors (18%)
reported near-death experiences. All 344 had been clinically dead, meaning
they were unconscious due to a lack of blood and oxygen to the brain.
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- The patients' near-death experiences varied, with 41
having a deeper, or ``core,'' experience. The rest reported more ''superficial''
events, van Lommel's team notes. Two years later, 6 of these individuals
were deemed to not have had a near-death experience.
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- But those patients who did have one were able to recall
the experience ``almost exactly'' 8 years later, the researchers found.
And in contrast with cardiac arrest survivors who did not have such an
experience, these patients showed less fear of death and a stronger belief
in an after-life.
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- What the researchers could not find was any clear explanation
for why a small percentage of patients had a near-death experience while
most did not. If ``purely physiological factors'' like a cutoff of oxygen
to the brain were at play, they note, most of the study patients should
have had such an experience.
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- ``We did not show that psychological, neurophysiological,
or physiological factors caused these experiences after cardiac arrest,''
the researchers write.
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- But these findings are hard to interpret, according to
an editorial published with the report. For one, writes Dr. Christopher
C. French of the University of London, UK, ``it seems that at least some
near-death experiences may be the result of false memories.''
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- In addition, he points out, it is unclear when--during
what state of consciousness--the patients had their experiences.
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- French calls for more research to overcome the limitations
of most studies into near-death experiences, while calling the current
one a ``major advance'' over past studies.
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- SOURCE: The Lancet 2001;358:2010-2011, 2039-2045.
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