According to our current medical concepts, it is not possible to experience consciousness during a cardiac arrest, when circulation and breathing have ceased. But during the period of unconsciousness due to a life-threatening crisis like cardiac arrest, patients may report the paradoxical occurrence of enhanced consciousness experienced in a dimension without our conventional concept of time and space, with cognitive functions, with emotions, with self-identity, with memories from early childhood and sometimes with (non-sensory) perception out and above their lifeless body. In a Dutch study on the near-death experiences (NDEs) of 344 survivors of cardiac arrest, published in The Lancet in 2001, several universal elements appeared in that groups’ NDEs.
In four prospective studies, with a total of 562 survivors of cardiac arrest, between 11% and 18% of the patients reported a near-death experience (NDE), and in these studies it could not be shown that physiological, psychological, pharmacological, or demographic factors could explain the cause and content of these experiences. Through many studies with induced cardiac arrest in both human and animal models cerebral function has been shown to be severely compromised during cardiac arrest, with complete cessation of cerebral flow, and electrical activity in both cerebral cortex and the deeper structures of the brain has been shown to be absent after a very short period of time (10-20 seconds). So we have to conclude that in cardiac arrest NDE is experienced during a transient loss of all functions of the cortex and of the brainstem. How is it possible for consciousness and memories to be experienced outside the body during a temporarily non-functioning brain? How could a clear consciousness outside one’s body be experienced at the moment that the brain no longer functions during a period of clinical death, with a flat EEG? How is consciousness related to the integrity of brain function? And is there a start or an end to consciousness? Scientific study of NDE pushes us to the limits of our medical and neurophysiologic ideas about the range of human consciousness and mind-brain relation, because we have to admit that it is not possible to reduce consciousness to neural processes as conceived by contemporary neuroscience.
Since the publication of these prospective studies on NDE in survivors of cardiac arrest, with strikingly similar results and conclusions, the phenomenon of the NDE can no longer be scientifically ignored. It is an authentic experience which cannot be simply reduced to imagination, fear of death, hallucination, psychosis, the use of drugs, or oxygen deficiency, and people appear to be permanently changed by an NDE during a cardiac arrest of only some minutes duration. According to these studies, the current materialistic view of the relationship between the brain and consciousness held by most physicians, philosophers, and psychologists is too restricted for a proper understanding of this phenomenon. There are good reasons to assume that our consciousness does not always coincide with the functioning of our brain: enhanced consciousness can sometimes be experienced separately from the body. I have come to the inevitable conclusion that most likely the brain must have a facilitating and not a producing function to experience consciousness.
By making a scientific case for consciousness as a nonlocal and thus ubiquitous phenomenon, beyond time and space, this view can contribute to new ideas about the relationship between consciousness and the brain. We can only measure the electrical, magnetic, chemical activities in the brain by EEG, MEG and PET-scan, and we can measure changes in blood flow in the brain by fMRI, but these are only neural correlates of consciousness. These measurements do not explain anything about the production nor about the content of consciousness. With our currently available scientific and objective techniques one is not able to even prove, measure, objectify nor falsify the content of the subjective experiences in our consciousness.
Recent research on NDE also seems to be a source of new insights into the possibility of a continuity of our consciousness after physical death. The findings and conclusions of recent NDE research may result in a fundamental change of one’s opinion about death, because of the almost unavoidable conclusion that at the time of physical death consciousness, with persistent self-identity, will continue to be experienced in another dimension, in which all past, present, and future is enclosed. As someone with an NDE wrote to me: “Death is only the end of our physical aspects.” But we should acknowledge that research on NDE cannot give us the irrefutable scientific proof of this conclusion, because people with an NDE did not quite die, but they all were very close to death, and without a functioning brain. However, it has now been scientifically proven that during NDE enhanced consciousness was experienced independently of a functioning brain. Without a body we still can have conscious experiences, we are still conscious beings.