Dr Peter Fenwick & Dr Pier-Francesco Moretti, Dr Vasileios Basios, and Martin Redfern write: "There can be no evidence clearer than the personal testament of someone who has died. Thanks to the success of medical interventions following cardiac arrest, many people do return from something that would have been classified as dead 50 years ago – a state in which the brain has ceased to function, the heart has stopped and the person is to all intents and purposes actually dead. And some report experiences which suggest the existence of another state of consciousness, unavailable in our normal everyday world.
"The international definition of death is: no respiration, no cardiac output and absent brain stem reflexes. This is the exact clinical state after a cardiac arrest. Simultaneous recording of heart rate and brain electrical activity show that within 11 seconds of the heart stopping, the brainwaves go flat. You are clinically dead.
"Consciousness is lost in a matter of seconds when the heart stops and may not be regained until hours to days after it restarts.
"Even if cardiopulmonary resuscitation (CPR) begins straight away, blood pressure will not rise high enough to establish an adequate blood flow through the brain. Doine Stub and Graham Nichol found that only 7% of cardiac arrest patients survived and most had some evidence of brain damage; and the mental state during recovery is confusional.
"The flat EEG indicating no brain activity during cardiac arrest and the high incidence of brain damage afterwards both indicate that unconsciousness is total. The brain can’t create images, so it should be impossible to have clearly structured and lucid narrative experiences and because memory is not functioning, if experiences did occur they should not be remembered. The brain does not begin to function again until the heart restarts. So in theory it is impossible for anyone in this state to a) experience or b) remember anything that occurred during it. And if an experience occurred during the gradual return to consciousness it would be confusional, and not the clear, lucid story which is characteristic of actual death experiences.
"However, to muddy the waters some studies have found that in patients who are being monitored and have begun the actual death process, there is a sudden recurrence of brain activity, containing faster frequencies which may last up to five minutes. Materialists have jumped on this as the explanation for the ADE. But this is random cortical activity which does not integrate different areas of the brain, and certainly could not restore consciousness.
"Conventional science cannot explain how an ADE could occur at any point during the death process, and there are special difficulties in accepting that it happens when the ADErs say it happens — during unconsciousness. However, about 10% of those who survive a cardiac arrest report an ADE .
"It is very difficult to judge the exact timing of an ADE during a cardiac arrest. But two prospective studies were of people who had had cardiac arrests and were resuscitated in coronary care units, where their medical records show exactly what had happened; the patients had the same medication and resuscitation procedures and could be questioned as soon as they were well enough.
"Of the 63 cardiac arrest survivors interviewed, 89% had no memories and about 10% reported ADEs, which they said had occurred while they were unconscious. These ADEs were, as was expected, very similar to those NDEs already reported in the literature. The authors also found that the ADEs were not due to medication, electrolytes, blood gases, religious belief or any other cultural factors.
"Other research groups have found similar results. In a Dutch study of 344 cardiac arrest survivors, 41 (about 12%) reported ADEs (van Lommel, 2011). Their occurrence was not influenced by the duration of unconsciousness or cardiac arrest, or by medication but more ADEs were reported in the group of survivors who died shortly after their experience. In another study a higher rate of 23% was reported (Schwaninger et al., 2002) about 10% were found by Greyson, (2003) , while others (Sartori et al., 2006) report about 25%. What is clear is that actual death experiences do occur in association with cardiac arrest, and their contents are similar to those reported in the NDE literature.
"No studies have so far been able to provide definitive scientific proof of when an ADE occurs. Parnia, with Fenwick and others (Parnia et al., 2001) found that the patients themselves felt that the experiences occurred during unconsciousness - important because, as discussed above, we have no idea how clear consciousness can be experienced during a period of clinical death with a flat EEG. This question is absolutely crucial to one of the biggest problems facing neuroscience: is consciousness entirely a product of brain function and is it confined to the brain? ADE research is perhaps the most promising way of filling the ‘consciousness gap’ in neuroscience. From the point of view of science, the ADE cannot occur during unconsciousness, and yet there is tantalizing evidence that that is just when they do occur.
"About a third of ADEs are preceded by an out of body experience in which the experiencer says they leave the body and rise to the ceiling and can see the resuscitation taking place. Anecdotal evidence points to the OBE and therefore the ADE occurring during unconsciousness. Certain subjects even described their own resuscitation procedures accurately, suggesting that their ADE had occurred when the brain was ‘down’ (Sabom, 1982).
"Dr. Penny Sartori studied a group of cardiac arrest survivors in a coronary care unit, several of whom said they had left their bodies and witnessed the resuscitation process. She compared their accounts of their resuscitation with those of another group of patients who had had no ADE during their resuscitation but were asked to describe what they thought had happened. It is usually argued that everyone sees so much resuscitation on TV that they know the procedure. Dr. Sartori was able to show convincingly that the patients who claimed to have seen their resuscitation, described it much more accurately than those who could only guess what had happened and who made significant errors (Sartori et al., 2006).
"Pamela had to undergo surgery to remove a cerebral aneurysm situated deep in the central structures of her brain. The operation was carried out in a specialized neurosurgery center under close medical monitoring during the entire operation. Her brain was cooled and EEG electrodes measured her brain activity. When the anesthesia had reached sufficient depth, the brain was known to be non-functioning. Pamela was clinically dead. Her circulation was taken over by a heart lung machine, the blood was emptied from her brain and the neurosurgeons removed the aneurysm. Then the heart was restarted, and the wound was closed.
"After the operation Pamela made several observations about what she had ‘seen’ during it which were acknowledged by the medical team to be correct. The best skeptics have been able to come up with to rebut this was that it was a case of ‘anesthesia awareness’, which does indeed occur under some circumstances, but is impossible in cases such as this when the brain is emptied of blood and clinically dead. Far more significant is the following comment on the case, from the British Medical Journal.
“There is still
much scientific work to be done before we can confidently suggest mind-body
separation during the NDE. Dr Spritzer, the neurosurgeon who operated on Pam
Reynolds, stated that he could not explain her NDE in the physiological state
she was in, commenting 'I don’t want to be so arrogant to be able to say that
there is no way it can happen'. Let us hope that all those engaged in
NDE research can adopt a similar attitude.” (BMJ-editorial, 2003).
“To Be And Not To Be. This is The Answer: Consciousness Survives,” essay for the 2021 Bigelow essay contest submitted by Dr Peter Fenwick & Dr Pier-Francesco Moretti, Dr Vasileios Basios, and Martin Redfern.
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