Near- Death Experiences:
The Organic and Psychological Origins of NDE Phenomena.
Discussion: Stephanie Lynne Thorburn.
In ‘Near- Death Experiences’ Chris Roe reflects that no theory provides a comprehensive explanation for features typical of NDEs. He suggests that psychological and physiological hypotheses succeed in explaining elements of NDE and provide us with a rich source of speculative predictions for future investigations. Greyson also views theoretical models as inconclusive observing, “No one physiological or psychological model explains all the common features of NDE.. A clear sensorium and complex perceptual processes during a period of apparent clinical death challenge the concept that consciousness is localized exclusively in the brain ”. (1)
For the sake of brevity, I will overview the most predominant contemporary organic and psychological theories of NDEs after a brief précis on key features and correlates to inform my discussion. In the interests of connecting NDE to the field of parapsychology, I have slightly elaborated Roe’s concepts. The effects of NDE can indeed be fundamental in changing outlooks and perceptions. Matthew Dovel (2), author of ‘My Last Breath’ has discussed the diverse spiritual aspects of near-death experiences in connection to greater perceived efficacy in empathy, telepathy, clairaudience, clairvoyance, precognition & remote viewing. Theoretical categories of explanation for NDE therefore comprise spiritual and religious, psychological and organic components.
Context of NDE- Brief Definition/ Features.
In Chris Roe’s chapter, he does justice to the complexity of NDEs, explaining the parameters of the subject, having traced the phenomena to the work of Raymond Moody in ‘Life After Life’, (1975). Key features of near-death experiences have been documented by Moody (1975) as including: - inability to put into words one’s experience, feelings of peace and quiet or occasional euphoria, a sense of being outside one’s body looking down, a dim light becoming intense and a panoramic review of one’s major life events; a sense is often reached of making the decision to return with a new sense of value for life. Kenneth Ring (1980) has extended these definitions to five core experiences utilising a structured interview and measurement scale. NDE can occur in either perceived or real near death states, Greyson (1983).
Correlates of NDE.
Roe suggests theories of near-death experience are illuminated by first considering what type of person and circumstances relate to NDE. The incidence of NDE does not seem related the demographics of age, gender, socio-economic status or ethnicity, Roberts and Owen (1988). Greyson and Stevenson (1980) found that NDE experients reported more prior mystical type experiences than comparison groups and Ring and Rosing (1990), noted incidence of childhood trauma and potential dissociative tendencies are higher in NDE experients. Finally, NDE are consistent throughout history and it is suggested that the process of NDE may be universal, but the specific imagery and interpretations ascribed to NDE are determined by the expectations and beliefs of individuals.
The Core Theories of NDE.
Spiritual Perspectives.
Roe rejects premature claims of the validity of spiritualistic perspectives, preferring the rationale of psychological and organic theories. He does however begin by elaborating the concept of mind and spirit separation in NDE favoured by the general public, Kellehear et al, (1990). The notion here is that NDE represents the afterlife, with popular subscribers to this view being Ring (1980) and Sabom, (1982). Theorists such as Sabom (1982) have claimed patients who have been resuscitated have seen things during NDE that could not have reconstructed from available sensory information or knowledge. The existence of ESP would explain the phenomenon of NDE and is supported by Bem and Honorton, (1994), although spiritualist theories do not explain cases of perceived rather than actual threat to life. It is however difficult to attain evidence for NDE being a literal experience of the afterlife as it is challenging to operationalise an immaterial interpretation using materialist scientific methods.
In ‘How Near-Death Experiences Work’, Ed Grabianowski explores supernatural and spiritual theories further and explains that acceptance of supernatural explanations is based on faith, spiritual and cultural background. NDE can be viewed as disembodied consciousness of the soul leaving the body to the afterlife, with a glimpse of another realm of being. Belief in astral projection connects NDE with other forms of out- of- body experience, offering potential proof of experience from a different perspective. For those of Judeo-Christian theology, NDE represent proof of souls, Heaven and Hell, whilst other theories are more esoteric implying a psychic connection to higher-level intelligent beings. It is suggested such entities may be humans with souls evolved beyond the birth-death reincarnation cycle, offering a glimpse of humanity’s future as high-order spiritual beings.
Psychological Theories.
Depersonalization.
Returning to Roe’s summary of more concrete explanations of NDE theories, depersonalisation is often proposed as a potential explanation. Pfister first cited this concept, (1930), attempting to account for the experiences of mountaineers when falling to what they thought was their deaths. A positive fantasy experience was thought to be a response to escape this experience in form of depersonalisation, Noyes (1972). When death seems inevitable it is proposed that fear is replaced by a sense of peace and resignation with a ‘panoramic life review’, reflecting premature grieving of one’s own death. This accounts for aspects of detachment, but not higher levels of alertness in near death phenomena, Irwin (1999).
NDE as a remembrance of birth experience.
The shock of being close to death has been suggested as evoking memories of the stress of birth, Grof and Halifax, (1977). In this account the dark tunnel represents the birth canal, with presence of others being connected to a parent or medics. This is however not considered a strong theory as the birth canal is not like a tunnel, with birth comprising a succession of ‘pushes’ and is far more stressful to the serenity of NDE. Becker (1982) has shown that infants do not have the visual-spatial or cognitive capacity to recall the birth experience.
Organic Theories.
Endorphins.
Stress can result in the release of endorphins. These are naturally produced opiates to reduce pain perception. Endorphins are also released near death and might be responsible for the positive emotions and calm reported, and it is interesting to note drugs that negate such neurochemicals might result in NDE that are more negative, Judson and Wiltshaw, (1983). Jansen (1997) argued that naturally occurring anaesthetic ketamine might trigger sensations of NDE. These compounds have a number of negative effects not characteristic of NDE and the effects also last much longer, Sabom, (1982).
Cerebral Anoxia.
It is often suggested that the common pathway to death is cerebral anoxia or a lack of oxygen supply to the brain, Rodin, (1980). The effects produced are that of well-being and power; it is therefore illuminating to consider the work of Whinnery, (1990, 1997). Whinnery examined the experiences of pilots unconscious during periods of rapid acceleration during the course of manoeuvres. Loss of consciousness at accelerating forces can reduce blood flow inducing anoxia. Whinnery found features similar to NDE involving floating sensations, out- of- body experiences and euphoria and fictional visions of meetings with family members, Blackmore (1993). However, it may not be the case that this is applicable to NDE as there is some evidence that anoxia is not necessarily a precursor to the phenomena. Sabom, (1982) for example, measured blood levels of oxygen and carbon dioxide during NDEs and found no significant differences in the experiences of individuals with and without anoxia. Better measures are needed, but anoxia is unlikely to be the sole cause of NDE.
Temporal Lobe Seizures.
It was theorised by Sabom and Kreutziger (1982), that hypoxia or impaired oxygen to the brain can give rise to temporal lobe epilepsy, with features similar to NDE. However, the researchers also noted qualitative differences in reports of the two experiences; seizure- induced perceptions tend to feature auditory imagery rather than visual for example, Irwin (1999). In NDE there is often no sound and in seizures memories are more random, unlike the ‘life review’ of NDE, Noyes and Kletti, (1977).
Hallucination.
Hallucinations can arise from some medications and physiological malfunctions. It is superficially possible that this could be an explanation of NDE although we can be sure some cases of NDE do not involve drugs, injury or malfunction and these NDE cases are essentially the same, Greyson, (2000). There is evidence that metabolically induced delirium may actually be an inhibitor of NDE, Osis and Haraldson, (1977). Hallucinations typically include confused thinking, disorientation and fear in contrast to the calm lucidity found in NDE.
The ‘Dying Brain’ Hypothesis.
Blackmore (1993) has offered perhaps the best-known and most popular theory of the NDE and suggests that different aspects of the NDE may be explained by a combination of psychological or physiological mechanisms. She differentiates between the features of the tunnel, light and noises probably caused by hypoxia and affective features of peace and well- being, due to the action of endorphins.
Blackmore explains the tunnel out- of- body experience as a result of neuronal disinhibition in the visual cortex. In this area the natural state for cells is to fire and they have to be suppressed from firing via inhibition - the first consequence of anoxia may be an increase in cell firing. Light receptors in the retina are more densely packed in the middle of the visual field, the more their impulses survive to the represented in the cortex, this increasing activity may be experienced as a light at the centre of the visual field, becoming increasingly bright and large as cells begin to fire, Blackmore and Troscianko, (1988). This process may be interpreted as movement toward the circle of light and the impression given of brilliant light would not be painful, as the eyes are not utilised in this perception. This explanation does not however explain cases where experients are not anoxic.
The out-of-body experience can be understood via Blackmore’s theory through our ordinary sense of self, as located behind the eyes, being in fact a construction. As our vision is the dominant sense, it seems natural for our ‘selves’ to be orientated at a point most tangible visually. Sense date is however in disarray in near- death experience or with hallucionogenic drugs, so this may break down as a model and be replaced by another that makes use of the remaining information. If the reconstruction relies on memory Blackmore suggests, we might expect the model to be in the third- person, i.e. viewing the scene from the outside. However there are elements of NDEs that cannot simply be accounted for as “vestigial hearing and guesswork”, Roe (2001).
Further systematic work needs to be undertaken to establish greater understanding of NDE, given the intriguing and powerful human experiences being addressed. In September 2008, it was announced that 25 UK and US hospitals will examine near-death studies of 1,500 heart attack patient-survivors and the 3 year study will be co-ordinated by Southampton university to determine if people without heartbeat or brain activity can have OBEs with veridical visual perceptions. (Jane Dreaper, BBC News, Sept. 2008). The results will be illuminating as some theorists contest cynicism regarding the nature of NDE on the basis of existing evidence. In ‘Scientific Theorists of the Near-Death Experience’, Kenneth Ring is quoted as describing the ‘burden of proof’ as falling on those who wish to explain NDE as purely neurological given the manifold consistent features of the phenomenon.
In conclusion I have evaluated near- death experiences in some degree of detail in regard to current comparative organic, psychological and spiritually orientated throries. Due to personal interest and respect of the depth and sensitivity attributable to this subject, I overviewed key theories, with a précis on the correlates, features and future implications for the study of NDE. A fruitful final quote to consider might be that of Nancy Evans Bush of the International Association of Near- Death Studies, who reflects on the illusive nature of NDE,
“There is no human experience of any description that can’t simply be reduced to a biological process, but that in no way offsets the meaning those experiences have for us, whether it’s falling in love, grieving or having a baby- or come close to death and having a transcendental experience.”
References and acknowledgements: -
‘Scientific Theories of Near-Death Experience’, from:
http://www.near-death.com/experiences/experts.01.html
Ed Grabianowski, ‘How Near-Death Experiences Work’, from: http://science.howstuffworkds.com/near-death-experience.3.htm
Roe, Chris. 'Near-Death Experiences', Chapter 11, from Roberts R. and Groome, D. (2001) Parapsychology: The Science of Unusual Experience.Hodder Arnold.
Footnotes Question 11, further online sources: -
1. Greyson, B. (2001). ‘Posttraumatic stress symptoms following near-death experiences’. American Journal of Orthopsychiatry, 71, 368-373.
2. Matthew Dovel’s website, re, the subjective parapsychological effects of NDE: - http://www.mylastbreath.com/side_effects_nde.htm
Further reading on the NDE debate: -
Journal of Near-Death Studies: http://www.kluweronline/issn/0891-4494
Roll, Michael. Head of Campaign For Philosophical Freedom. (Alternative perspective to that theorised by Dr. Susan Blackmore.) ‘The Scientific Proof Of Life After Death’.
http://www.cfpf.org.uk/articles/background/scientificproof/scientificproof1.html
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