Near-death experiences (NDEs) have been reported for much of human history. There is evidence in early Greek and Roman literature, in medieval Western religious literature, ancient literature of Buddhism, and the oral history and folklore of aboriginal societies in Australia, North and South America, and Oceania. The parapsychological literature has discussed NDEs since the nineteenth century, however the popular discussion of these experiences only dates from the early 1970s with the publication of Raymond Moody's best-selling Life After Life (1975). Moody coined the term near-death experience but later regretted its overidentification with physical death and changed the term for these experiences to paranormal deaths.
In Life After Life Moody discussed fifty individual cases of people who, when unconscious and apparently near death and then resuscitated, reported conscious social and psychological experiences. Some people reported sensations of traveling in a dark tunnel. Others reported meetings with bright beings of light or deceased relatives and friends.
Since this early book of casual observations from an author who had been an academic philosopher retrained as a medical practitioner first appeared, other more research-based books have been published. Among these are the behavioral and clinical studies of the psychologist Kenneth Ring (Life At Death 1980), the cardiologist Michael Sabom (Recollections of Death 1982), and the psychotherapist Margot Grey (Return from Death 1985). These were soon followed by other studies from parapsychology, religious studies, sociology, philosophy medicine, and particularly psychiatry.
Among the many studies that have been published since Moody's work include several that have been conducted with children. Childhood NDEs are similar to those reported by adults with some minor differences in phenomenology. Life review, for example, is present for those with a long enough life to recall. Children seem to more often see animals in their NDEs than do adults, suggesting that perhaps animals are one of the few "dead beings" a child might expect to see in such a state. The incidence of NDEs is extremely difficult to assess and depends much on the definition one uses as much as the methodology one employs. In clinical settings, frequently employing cardiac patients, the incidence has been reported in the vicinity of between 9 percent and 18 percent.
Estimates of incidences within the general population have been attempted with surveys. Researchers estimate that approximately 5 percent of the United States population has experienced an NDE, which has led researchers in the U.S. to suggest that some 10 million Americans have had an NDE and in Germany over 3 million people have experienced NDEs.
Some twenty years after the initial observations and theories studies have uncovered and discussed negative NDEs—experiences near death that are less than pleasant for the person in this near-death state. In these accounts, people visit dark places, encounter cruel or taunting beings, and experience feelings of sadness or anxiety. As of 2001 there have been few psychological or social correlates to predict NDEs, either of the positive or negative variety. Gender, age, class, and religious affiliation do not appear to play any role in predicting these experiences. There are some circumstantial correlates, such as surgical or suicide patients who appear not to experience life review compared to those whose injuries or illnesses are of sudden onset. But most of these predictive correlates appear to predict one or more NDE features (e.g. lights, life-reviewed, tunnel sensations, etc.) rather than actual incidence.
The professional and popular profile of NDEs has exploded since the 1970s. It is not immoderate to claim the NDE has become an important and central subject of study and entertainment since the late twentieth century. Moody's book has sold some 12 million copies to date. Film and video consistently employ NDE imagery in their scenes of death—from Flatliners (1990) to What Dreams May Come (1998). Several autobiographical NDE accounts have made the New York Times best-seller list.
The International Association for Near-Death Studies was established in the early 1980s in the United States, with chapters in the United Kingdom, Europe, Canada, and Australia. The association has an academic peer-review journal— Journal of Near-Death Studies —edited from the Department of Psychiatry at the University of Virginia Medical School. Articles about the NDE have appeared in prestigious medical journals including Lancet, British Medical Journal, Journal of Nervous and Mental Disease, and the American Journal of Psychiatry, among many others.
Understandably, near-death studies have drawn major theoretical debate from several quarters, in particular New Age and skeptical writers. Church leaders and writers are divided. Some side with materialist medical theories, while others argue that such experiences are the work of darker forces. Others allow that such experiences may be revelations into some larger human and perhaps divine dimension.
New Age writers, influenced by modern spiritualism and Eastern religions, have found the afterlife imagery rich in suggestion and confirmation about the eschatological theories of these influences. Skeptics, wary of religious resurgence and supernatural explanations, have tended to scrutinize the case details and research methodologies more carefully. They have tended to favor neuroscientific theories of explanation, particularly those with behavioral and psychobiological models of consciousness.
Among the chief psycho-neuro-biological theories of NDE have been theories of sensory deprivation and cerebral anoxia. Both events have been traced to abnormal temporal lobe seizure activity or the release of ketamines or other hormonal and chemical reactions in the brain. There have been theories about the role of drugs—both medical and illicit—but these took less prominence as more NDEs were reported in situations where these drugs were not implicated. The central problem with biological theories of NDEs is that most of these assume the experience to be closely associated with unconscious states. Increasingly this appears to be less the case.
There has been less effort in surveying the cross-cultural evidence around these experiences, yet it is here where the diversity of NDEs becomes increasingly apparent. What examination there has been in this area seems to indicate that the stereotypical profile of NDEs as an unconscious experience enjoys significant variation. Experients (people who experience NDEs) from hunter-gatherer societies, for example, tend not to report tunnel sensation or life review—an important observation that could undermine the credibility of attempts to create particular neurophysiological theories based up on these two details.
However, taking the stereotypical NDE profile of sensations of euphoria, out-of-body experience, tunnel sensation, life review, and meetings with beings of light or deceased people has also opened up another model of near-death experiences as experiences not near death and not unconscious. Here, similar phenomenology has been reported in connection with shamanic initiation rites, castaway experiences, experiences of trapped miners, mountaineering accidents, and bereavement experiences.
Further complicating the question of causation is the finding that near-deathlike experiences may be induced in therapeutic settings through use of eye-movement desensitization and reprocessing (EMDR) techniques in psychotherapy. During grief therapy using EMDR techniques, patients may experience reunion with deceased relatives and friends, tunnel sensation, experiences of light and peace, and the observation of supernatural vistas. Near-death experiences are no longer phenomena simply associated with unconscious experiences of cardiac arrest and resultant resuscitation.
The examination of these kinds of conscious experiences has lead to the recognition of two important points. First, NDE phenomenology is not always associated with real, physical experiences of death but merely the expectation of dying and loss. Second, NDE phenomenology is associated with conscious as well as unconscious experience. These observations immediately call into question theories of NDE that rely on unconscious cases and that employ cerebral anoxia (oxygen deprivation of the brain) as their primary mechanism of causation. Any physiological theories of NDE must take into account that the phenomenology spans conscious and unconscious experiences and enjoys significant cultural variation.
Notwithstanding these qualifications, it is important to note that physiological theories have no more power in undermining supernatural explanations than New Age theories have of establishing them. The issue of whether consciousness is merely a function of physical processes or is mediated by them is not settled by biological debate, least of all one with obvious materialist assumptions.
The issue of the nature of consciousness and death, specifically the fate of consciousness beyond death, is a philosophical question. It is not settled by empirical claims if only because all scientific conclusions are subject to revision. And because they are ipso facto empiricist models of explanation, such models are biased against theories of experience not subject to these types of tests and proofs.
The nature of death or of consciousness is also not settled by logical argument if only because there are always better arguments to be made, and will need to be made, by the changeable requirements of a diverse and evolving professional and academic culture. The arguments about human survival are made in the service of persuasion and are rarely definitive except to those with faith—in religious or scientific, materialist ideas. Evidence and argument must have a context to be persuasive within. They are most effective among a community of believers. This remains true of twenty-first-century skeptics and religious adherents.
Even away from the ideological posturing of the more extreme opinions from religion and science, NDEs are not readily explained by current neurophysiology. Some researchers have argued that drugs may be implicated, but often they are not. Other researchers have argued that tunnel sensation is due to the side effects of oxygen deprivation to the brain, but NDEs occur to people who are fully conscious as well.
Personality changes linked to disturbances to temporal lobe, such as religiosity, philosophical pursuits, widening affect and so on, have been associated with obsessiveness, humorlessness, anger, and sadness—qualities not normally associated with NDEs. There have been claims that NDEs have occurred when patients were connected with electroencephalograph (EEG) machines, but these claims were subsequently proven false. There are now documented cases, but the reliability and validity issues behind measurement of brain activity are far from certain and so such cases are intriguing at best and irrelevant at worse.
What scientists are able to say is that the research to date has provided fruitful indicators of the type of brain/consciousness models that are needed to further explore and understand the physiological basis of these experiences. Advances in this scientific area will undoubtedly supply researchers with a basic benchmark for understanding the broad biological context of NDEs but they do not solve, and probably will never solve, the diverse incidents and experiences that are regularly reported near death. In this context, the best answer researchers will ever have when it comes to the question of whether or not NDEs represent evidence of human survival of death is that perhaps they might, but rarely conclusively.
Implications of Near-Death Experiences
Aside from the professional debates about the causes of NDEs there lies a major discussion about their consequences. Those whose NDEs are clinically derived from close physical encounters with death often report changed values and lifestyles. Those whose NDEs are derived from initiation rites, castaway experiences, or mining accidents also report life changes. These changes to values or lifestyles are associated with both positive and negative NDEs, although such changes may be dissimilar from each other. For people whose NDE is a positive experience, many report a lessening or disappearance of any personal fear of death. These people also report a greater "love of humanity," often expressed as a desire to change career or work aspirations so as to work for the good of others.
There is a greater expressed desire to be more tolerant or patient of human foibles and a greater appreciation for the interconnectedness of all living things. Those who encounter near-death experiences report an increase in their interest in spirituality but often expressly distinguish this from a church-going religiosity. Many other people have reported an increased interest in education or higher learning. This is often associated with a simple post-NDE desire for learning, but also for retraining into some kind of helping profession to meet their newly found ambition to "help others." People who have experienced a negative NDE will often, understandably, report a greater fear of death, and are more likely than those with positive experiences to return to church attendance.
There has been some suggestion that those who experience near-death experiences encounter a new type of consciousness. NDEs create human beings that have higher spiritual values and such people are important to an evolution of improved social and political values within humanity. But it is not at all clear that the research on post–NDE changes in individuals reflects genuine changes or simply new attitudes and hopes in these people. People often report stigma and rejection of their new attitudes and values, while many others are even skeptical of the actual NDE itself. Many near-death participants have reported being withdrawn or depressed about such responses and more than one book has recorded that the diverse reactions of people and their networks have lead to job loss and marital breakdown.
It appears that experiences of light and love near death no more makes a better person than any other experience of crisis. Experiences that are testing and challenging to one's personal values and character can transform one for the better or may destroy that person. But it is not the experience that holds the key, but one's capacity to learn and be changed by that experience. In this way, NDEs occupy similar psychiatric and social space as bereavement, job loss, poverty, personal failure, and social rejection. They may be sufficient but not guaranteed grounds for personal growth and change.
As mentioned previously, the NDE is not confined to people near death or loss. It may also take "passengers." In his book The Last Laugh (1999), Moody calls these experiences "empathic," "conjoint," or "mutual" NDEs. People caring for dying people may report some actual NDE phenomenology—experiences of light, out-of-body experiences, meeting supernatural or deceased beings, and enjoying sensations of peace and joy. These are part of a discreet subset of near-death phenomenology such as shared near-death visions, shared near-death experiences, and shared illness experiences. They have been reported in early-nineteenth-century parapsychology literature and in late-twentieth-century near-death studies and literature.
The social and psychological pattern for their appearance seems to be a personal journey that takes the dying or ill person through similar stages of social isolation and reintegration. The number of reported cases of shared NDE are small and their documentation inconsistent in thoroughness. Yet, such cases continue to strengthen the importance of the social and psychological nature and complexity of NDEs. There can be no doubt that biological factors play a role but it may yet turn out to be a diverse mediating one, subject to equally complex social factors. Just as the physiology of smiling is no key to the secret of happiness, the physiology of NDEs may not unlock the secret of the fate of the soul nor even of its whereabouts.
The problem of NDEs appears to tread similar territory to other problems of social and psychological marginalization. In that space, NDEs are areas of contested social meanings between modern-day "experts" of one persuasion or another, and individuals trying to make sense of experiences for which science and religion have poorly prepared them. Without a settled, agreed-upon set of meanings, the status of NDEs, their passengers, and their public relationships with the outside world will always be ambiguous and problematic.
See also: Communication with the Dead; Communication with the Dying; Immortality; Moment of Death; Reincarnation
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After a near-death experience many people report that their whole attitude to life is changed. They are less concerned with material things and more interested in helping others. Research confirms these changes but it is not clear whether they are a consequence of the experience itself or just of having been so close to death.
Not all near-death experiences are blissful, and recent research has discovered an increasing number of hellish experiences — although just how many is hard to estimate, since people may be less likely to report them, and more anxious to forget. In many religions suicide is treated as a sin, so believers might expect those who attempt suicide to be especially likely to have hellish experiences. In fact they mostly report blissful or peaceful feelings, and the effect, far from encouraging another suicide attempt, seems to be a renewed enthusiasm for life.
The term ‘near-death experience’ became popular only after Raymond Moody's best-selling collection of accounts in 1975. However, similar reports had previously been collected from people who subsequently did die (i.e. deathbed experiences). In fact, reports of such experiences are widespread in many ages and cultures, and in literature, art, and film. Plato describes one in the Republic, Tibetan Buddhist literature includes the ‘returned from the dead’ writings, and there are myths from as far apart as ancient Greece, nineteenth-century native Americans, and Lithuanian folklore. In contemporary research, similar reports have been collected from Iceland, Britain, America, and India. In these accounts the basic features tend to be similar (including tunnels, lights, out-of-body excursions, and visions) but the details vary. For example, religious figures are often seen, but usually of the person's own religion. No Hindu is known to have seen Jesus, nor any Christian to have seen Hindu gods.
A few sceptics attribute the experiences either to wishful thinking or to taking drugs. This seems most unlikely, given the cross-cultural findings, and research showing that most drugs tend to reduce the clarity and complexity of near-death experiences. The important question is therefore why these experiences occur in a similar form all across the world.
The main contenders are either that near-death experiences are a glimpse of life after death, or that they are the effect of changes in an almost dying brain. The after-death hypothesis cannot be proven. If there is life after death, these experiences may tell us what it is like, but since none of the people concerned actually died we can never be sure. The closest we come to evidence is the claim that, during the experience, some people were able to see events at a distance that they could not possibly have known about or guessed. These claims are few, and none is substantiated by independent witnesses or physical evidence, although the best examples are probably those in which patients were able to describe complex medical procedures that occurred while they were comatose or even clinically dead.
There are several theories to explain how coming close to death can give rise to near-death experiences. Lack of oxygen is often implicated, although many near-death experiences occur when people are not deprived of oxygen, as in falls from mountains, during suicide attempts by jumping from heights, or after accidents. In such situations, however, the production and actions of various hormones and neurotransmitters may be affected. There are theories based on stimulation of receptors in nerve cell membranes called NMDA receptors, on the effects of the neurotransmitter serotonin, and on the level of endorphins (the brain's own morphine-like chemicals). Endorphins are known to produce positive emotions and reduction of pain, and may be responsible for the blissful feelings in the midst of pain and fear. Disruption of the brain's neurotransmitters can produce random or excessive firing of neurons and this, depending on where it occurs, may produce the other experiences. For example, electrical stimulation of the temporal lobe of the cerebral hemispheres can produce life reviews and sensations of floating or flying, while random firing in the parts of the visual cortex (which also occurs with drugs such as LSD) causes the perception of lights, tunnels, and spirals.
These physiological explanations can account for much of near-death experiences, and may in time provide a complete account. Even so, they can never disprove the possibility of life after death. Some people may still prefer to believe that the experience is a glimpse of the next world rather than the product of the dying brain.
Bailey, L. W. and Yates, J. (ed.) (1996). The near-death experience: a reader. Routledge, New York and London.
Blackmore, S. J. (1993). Dying to live: science and the near death experience. Prometheus, Buffalo, NY.
Moody, R. A. (1975). Life after life. Mockingbird, Atlanta, GA.
Individuals who have shown many of the characteristics of death (stopped heart, flat brain scan, etc.) but have survived and been brought back to consciousness often report experiences that seem to have a bearing on the questions of individual survival of death and the possible existence of a human soul or surviving individual consciousness. Such experiences have been studied in modern times under the category of "near-death experiences."
Common to many such experiences is the powerful sensation of rushing through a long dark tunnel with a bright light at the end. This light brings an ecstatic feeling of joy, peace, and freedom from the body. Often the tunnel experience is preceded by a detached awareness in which some higher reality is interfused with perception of the physical environment surrounding the body, which may be perceived from a detached viewpoint, in which the self can look down on its own body, as in out-of-the-body travel. [Crucial to understanding the accounts of such experiences is separating the elements of the experience from the interpretation placed upon it by the person who has had the experience.]
Psychologists and doctors who have studied near-death experiences have also examined reports of out-of-the-body experiences, and have found enough commonalities to suggest that they are varieties of the same experience, the near-death experience often being distinguished by its intensity, its vividness, and its impact upon the person having the experience. For example, tunnel experiences are common to both, and as is the experience of viewing the physical body from a perspective outside of it. Many individuals find that such experiences are a powerful vindication of religious beliefs such as the existence of a soul as a separate entity from the body and the possibility of the continuation of the soul beyond the experience of bodily death. Clergy who undergo the experience are likely to change their views and teachings.
Various mundane theories have been offered to account for near-death and out-of-the-body experiences in terms of hallucination. For example, the tunnel sensations might be a reliving of the powerful experience of passing through the birth canal, since the baby usually emerges head first. Another psychological explanation centers upon the behavior of cells in the visual cortex when the brain is hyperactive through lack of oxygen. For a thoughtful examination of psychological theories, see the 1989 article, "Down the Tunnel" by Susan Blackmore. Blackmore has studied out-of-body experiences as a psychological phenomenon, but unlike most psychologists who theorize about such experiences, she has actually had such an experience herself. She rightly draws attention to the fact that skeptical explanations ignore the intense insightful and spiritual aspects of such experiences.
Investigators from different disciplines will emphasize their own bias. Allan Kellehear, who comes from a sociological perspective, compares the experience to crisis situations that happen to those lost at sea or trapped in a mine. Melvin Morse is a pioneer working with children who have NDEs and he finds that experiencers in this group to be contaminated by the life experiences that adults have accumulated.
Since 1981, research on the near-death experience has been focused by the International Association for Near-Death Studies founded in 1981 and headed by Kenneth Ring. It published a monumental study of the phenomenon in 1980 and has an active presence on the web. Whether the phenomenon is completely understood or not it has become increasingly important because half the recipients of medical procedures are likely to have a near-death experience.
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Gallup, George, Jr., with William Proctor. Adventures in Immortality. New York: McGraw-Hill, 1982. London: Souvenir Press, 1983.
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International Association for Near-Death Studies. http://www.iands.org. April 10, 2000.
Kellehear, Allan. Experiences Near Death: Beyond Medicine and Religion. New York: Oxford Univ Press, 1996.
Kübler-Ross, Elisabeth. On Death and Dying. New York: MacMillan, 1969.
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——, and Evelyn E. Valarino. Lessons from the Light: What We Can Learn from the Near-Death Experience. New York: Insight Books/Plenum Press, 1998.
SpiritWeb: NDE, Near Death Experiences. http://www.spiritweb.org/Spirit/nde.html. April 10, 2000.
Wilson, Ian. The After Death Experience. London: Sidgwick & Jackson, 1987.
Zaleski, Carol G. Otherworld Journeys: Accounts of Near-Death Experiences in Medieval and Modern Times. New York: Oxford University Press, 1987.
Intense, pleasant, and sometimes profound experiences that people report when they have "come back" from states close to death.
Tales of near-death experiences (NDEs) are not unusual. Out-of-body experiences, the sensation of moving through a tunnel toward a light, the review of the events of one's life, and pleasurable glimpses of other worlds are relatively consistent features of people's "near death" reports. In fact, research suggests that almost one fifth of Americans report having almost died, and a large proportion of them have recounted experiences like the ones mentioned above. The reported events are very vivid, seem completely real, and can sometimes transform people's lives. How to explain these experiences is the subject of debate. Throughout history people have interpreted them as journeys toward the divine. The out-of-body experience was the soul or spirit leaving the body, the tunnel was the passageway, the life review was the time of judgement, and the light at the end of the tunnel was heaven (or the equivalent).
It appears that, rather than any spiritual journey or other world phenomenon, NDEs may be best understood by examining human physiology, neurochemistry, and psychology. At this time, there is strong research evidence to indicate that many of the symptoms of NDEs may be caused by anoxia, or a lack of oxygen to the brain . In the human visual system, for example, neurons (brain cells) deprived of oxygen will start to fire out of control. Since the majority of the cells in our visual cortex (the portion of the brain where visual information is processed) respond to stimulation in the central visual field, the result is a white spot in the center with fewer cells firing out of control in the periphery. As oxygen deprivation continues, the white spot grows and the sensation of moving through a tunnel toward a white light is produced. Similarly, it is possible that the life review process is a result of depriving the temporal lobes of oxygen. When the temporal lobes of the brain, an area largely involved in memory production, are deprived of oxygen, neurotransmitters are released and massive electrical activity ensues. In laboratory research, when people's temporal lobes are stimulated with electrodes, many subjects experience the reliving of memories, out of body experiences, and even the sensation of moving through a tunnel toward a light. Oxygen deprivation can also affect the limbic system, which contains the seat of emotions in the brain. The intensely pleasurable feelings of love and well-being that accompany moving toward the light may therefore be a consequence of increased activity in the limbic system.
According to some people, the similarities among people's accounts of NDEs provide powerful evidence for the existence of an afterlife. These similarities however, can also be interpreted as evidence in support of the involvement of human physiology, neurochemistry, and psychology. The visual cortex, temporal lobes, and limbic system are structurally and functionally common to everyone. Consequently neurological activity associated with stress or oxygen deprivation may be similar across many different individuals.
Blackmore, S. "Near-death experiences: In or out of the body?" Skeptical Inquirer, 16, (1991): 34-45.