Do you believe in
life after death?
Many people believe
in ghosts and heaven, and about three in 100 Americans report actually having
near-death experiences. These typically include an awareness of being dead,
out-of-body experiences, meeting dead people, entering tunnels of light, and so
on.
But these are
stories and anecdotes; what does science have to say?
A new article
published in Trends in Cognitive Sciences
by neuroscientist Dean Mobbs, of the University of Cambridge's Medical Research
Council Cognition and Brain Sciences Unit, and Caroline Watt, of the University
of Edinburgh, finds that "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."
Mobbs and Watt noted
that many classic NDE symptoms are actually reported by people who were never
in danger of dying in the first place. This suggests that the perception that
one is near death is traumatic and disturbing enough to cause some of the experiences.
Researcher Susan
Blackmore, author of Dying to Live: Near-Death
Experiences (Prometheus Books, 1993), notes that many NDEs (such as
euphoria and the feeling of moving toward a tunnel of white light) are common
symptoms of oxygen deprivation in the brain.
The new paper also
discussed something called "walking corpse" syndrome, named after
French neurologist Jules Cotard. Co-author Watt told Discovery News, "The
sufferer feels that he or she is dead, even though not actually near death. It
can be associated with trauma and some illnesses. It's not fully understood why
individuals suffer from Cotard syndrome, but one possibility is that it's the
brain's attempt to make sense of the strange experiences that the patient is
having.
"This is
relevant to NDEs because the near-death experience may also arise out of an
attempt to interpret unusual physiological and psychological experiences, and
the NDE includes the perception that one is not alive in the normal sense of
the word."
Watt's research also
busts another myth: that people have "returned from the dead" -- if
by dead you mean clinical brain death.
No one has survived
true clinical death (which is why the experiences are called near-death). Many people have been revived
after their heart stopped for short periods of time -- around 20 minutes or
more -- but anyone revived from brain death would be permanently and
irreparably brain damaged and certainly unable to report their experiences.
"The idea of
surviving clinical brain death is mythical," Watt said. "NDEs are
sometimes reported after a person experiences some of the preliminary 'stages'
of death -- for instance, when the heart stops beating for a while and the
person is then revived. I think it's curious, however, that a survey has shown
that 82 percent of individuals who have survived being actually near death do
not report a near-death experience. That would seem to undermine the idea that
these experiences give a glimpse into life after death."
Watt believes that
near-death experiences hold an enduring fascination for people because they
like the idea that humans survive bodily death.
"Some people
find this a comforting idea," Watt said, "because it suggests we are
not simply like other biological organisms on our planet."
The fact that
near-death experiences can be chemically induced and explained by neurological
mechanisms suggests a natural -- instead of supernatural -- cause.
CREDIT: DISCOVERY SCIENCE
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