Neuroscientist Mario Beauregard writes: "Near-death experiences (NDEs) are vivid, realistic, and
often deeply life-changing experiences occurring to individuals who have been
psychologically or physiologically close to death. A
clear memory of the experience, enhanced mental activity, and a conviction that
the experience is more real than ordinary waking consciousness are core
features of NDEs (Greyson, 2011).
"NDEs are frequently evoked by cardiac
arrest. When the heart stops, breathing stops as well, and blood flow and
oxygen uptake in the brain are rapidly interrupted; the EEG becomes isoelectric
(flat-line) within 10-20 seconds, and brainstem reflexes vanish (Clute &
Levy, 1990); the individual having the cardiac arrest is then considered to be
clinically dead. Because the brain structures supporting conscious experience
and higher mental functions (e.g. perception, memory, and awareness) are
dramatically impaired, cardiac arrest survivors are not expected to have clear
and lucid
mental experiences during the cardiac arrest period that will be remembered.
"Nonetheless, studies carried out in the United Kingdom (Parnia et al., 2001),
the Netherlands (van Lommel et al., 2001), Belgium (Lallier et al., 2015), and
the United States (Schwaninger et al., 2002; Greyson, 2003) have revealed that
about 15 percent of cardiac arrest survivors do report some recollection from
the time when they were clinically dead. In these studies, more than 100 cases
of full-blown NDEs were reported. It is noteworthy that while they are
clinically dead, NDErs sometimes report perceptions that coincide with reality.
"Advocates of materialist theories of the
mind object that even if the EEG is isoelectric, there may be some residual
brain activity that goes undetected because of the limitations of scalp-EEG
technology. This is possible, given that scalp-EEG technology measures mostly
the activity of large populations of cortical neurons. However, the brain
activity agreed upon by contemporary neuroscientists as the necessary condition
of conscious experience is well detected via current EEG technology, and is
clearly abolished by cardiac arrest (Greyson, 2011).
"Proponents of materialist
theories of the mind also argue that NDEs do not occur during the actual
episodes of brain insult, but just before or just after the insult, when the
brain is more or less functional (Saavedra-Aguilar & Gómez-Jeria, 1989;
Blackmore, 1993; Woerlee, 2004). The problem with this interpretation is that
unconsciousness generated by cardiac arrest leaves patients amnesic and
confused for events occurring immediately before and after such episodes
(Aminoff et al., 1988; Parnia & Fenwick, 2002; van Lommel et al., 2001)."
Mario Beauregard, “The Next Great Scientific Revolution,”
in Beauregard, Mario; Dyer, Natalie; Woollacott, Marjorie. Expanding Science:
Visions of a Postmaterialist Paradigm, Vol. 2, Postmaterialist Sciences
Series (pp. 21-23). The Academy for the Advancement of Postmaterialist Sciences
(AAPS), 2020. Kindle Edition.
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syncope associated with malignant ventricular arrhythmias. Annals of Internal
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Blackmore, S.J. (1993). Dying to Live:
Science and the Near- Death Experience. London: Grafton.
Clute, H. L. & Levy, W. J. (1990).
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Greyson, B. (2003). Incidence and
correlates of near-death experiences in a cardiac care unit. General Hospital
Psychiatry, 25 (4), 269-276.
Greyson, B. (2011). Implications of
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and Spirituality, 2 (1), 37-45.
Lallier, F., Velly, G., & Leon, A.
(2015). Near-death experiences in survivors of cardiac arrest: a study about
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Parnia, S., & Fenwick, P. (2002).
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Saavedra-Aguilar, J. C. &
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van Lommel, P., van Wees, R., Meyers, V. & Elfferich,
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