A near-death experience (NDE) refers to personal experiences associated with impending death, encompassing multiple possible sensations including detachment from the body, feelings of levitation, total serenity, security, warmth, the experience of absolute dissolution, and the presence of a light. These phenomena are usually reported after an individual has been pronounced clinically dead or has been very close to death. With recent developments in cardiac resuscitation techniques, the number of reported NDEs has increased. The experiences have been hypothesized in medical journals as having the characteristics of hallucinations, while parapsychologists and a number of scientists have pointed to them as evidence of an afterlife and mind-body dualism. Religious believers tend to be divided on and uncertain about their interpretation of NDEs, given that while they verify some aspects of the faiths, they also explicitly falsify other aspects. According to the 2013 PLOS ONE article by Thonnard et al., "near-death experiences cannot be considered as imagined event memories. On the contrary, their physiological origins could lead them to be really perceived although not lived in the reality."
Popular interest in near-death experiences was initially sparked by Weiss's 1972 The Vestibule, followed by Raymond Moody's 1975 book Life After Life and the founding of the International Association for Near-Death Studies (IANDS) in 1981. According to a Gallup poll, approximately eight million Americans claim to have had a near-death experience. Some commentators, such as Simpson, claim that the number of near-death experiencers may be underestimated. People who have had a near-death experience may not be comfortable discussing the experience with others, potentially due in part to some seeing an NDE as a paranormal experience. NDEs are among the phenomena studied in the fields of psychology, psychiatry, and hospital medicine.
- 1 Characteristics
- 2 Research
- 3 Personal experiences (self-reported)
- 4 See also
- 5 References
- 6 External links
The earliest accounts of NDE can be traced to the Myth of Er, recorded in the 4th century BC by Plato's The Republic (10.614-10.621), wherein Plato describes a soldier telling of his near-death experiences.:115:96–99
The cognate French term expérience de mort imminente (experience of imminent death) was proposed by the French psychologist and epistemologist Victor Egger as a result of discussions in the 1890s among philosophers and psychologists concerning climbers' stories of the panoramic life review during falls. In 1968 Celia Green published an analysis of 400 first-hand accounts of out-of-body experiences. This represented the first attempt to provide a taxonomy of such experiences, viewed simply as anomalous perceptual experiences, or hallucinations. These experiences were popularized with the work of psychiatrist Raymond Moody in 1975 as the Near-Death Experience (NDE). It is uncertain if Moody was aware of the expression earlier used by Egger.
Researchers have identified the common elements that define near-death experiences. Bruce Greyson argues that the general features of the experience include impressions of being outside one's physical body, visions of deceased relatives and religious figures, and transcendence of egotic and spatiotemporal boundaries. Many different elements have been reported, though the exact elements tend to correspond with the cultural, philosophical, or religious beliefs of the person experiencing it:
The traits of a classic NDE are as follows:
- The notice of unpleasant sound or noise (claimed by R. Moody).
- A sense/awareness of being dead.
- A sense of peace, well-being and painlessness. Positive emotions. A sense of removal from the world.
- An out-of-body experience. A perception of one's body from an outside position. Sometimes observing doctors and nurses performing medical resuscitation efforts.
- A "tunnel experience". A sense of moving up, or through, a passageway or staircase.
- A rapid movement toward and/or sudden immersion in a powerful light. Communication with the light.
- An intense feeling of unconditional love and acceptance.
- Encountering "Beings of Light", "Beings dressed in white", or similar. Also, the possibility of being reunited with deceased loved ones.
- Receiving a life review, commonly referred to as seeing one's life flash before one's eyes.
- Receiving knowledge about one's life and the nature of the universe.
- Approaching a border, or a decision by oneself or others to return to one's body, often accompanied by a reluctance to return.
- Connection to the cultural beliefs held by the individual, which seem to dictate the phenomena experienced in the NDE and the later interpretation thereof (Holden, Janice Miner. Handbook of Near-Death Experiences. Library of Congress Cataloging in Publishing Data, 2009.).
- Body separation
- Entering darkness
- Seeing the light
- Entering the light
He stated that 60% experienced stage 1 (feelings of peace and contentment), but only 10% experienced stage 5 ("entering the light").
Clinical circumstances associated with near-death experiences include cardiac arrest in myocardial infarction (clinical death); shock in postpartum loss of blood or in perioperative complications; septic or anaphylactic shock; electrocution; coma resulting from traumatic brain damage; intracerebral hemorrhage or cerebral infarction; attempted suicide; near-drowning or asphyxia; apnea; and serious depression. In contrast to common belief, Kenneth Ring argues that attempted suicides do not lead more often to unpleasant NDEs than unintended near-death situations.
The distressing aspects of some NDEs are discussed more closely by Greyson and Bush.
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Karlis Osis and his colleague Erlendur Haraldsson argued that the content of near death experiences does not vary by culture, except for the identity of the figures seen during the experiences. For example, a Christian may see Jesus, while a Hindu may see Yamaraja, the Hindu king of death. However, Yoshi Hata and his team reported NDEs with substantially different contents than those described above.
Some NDEs have elements that bear little resemblance to the "typical" near-death experience. Anywhere from one percent (according to a 1982 Gallup poll) to 20 percent of subjects may have distressing experiences and feel terrified or uneasy as various parts of the NDE occur, they visit or view dark and depressing areas or are accosted by what seem to be hostile or oppositional forces or presences. Persons having bad experiences were not marked by more religiosity or suicidal background. According to one study (Greyson 2006) there is little association between NDEs and prior psychiatric treatment, prior suicidal behavior, or family history of suicidal behavior. There was also little association between NDEs and religiosity, or prior brushes with death, suggesting the occurrence of NDEs is not influenced by psycopathology, by religious denomination or religiosity, or by experiencers' prior expectations of a pleasant dying process or continued postmortem existence. Greyson (2007) also found that the long term recall of NDE incidents was stable and did not change due to embellishment over time.
Bush (2012), a counselor, and board member and former Executive Director to the International Association for Near-Death Studies, holds that not all negative NDE accounts are reported by people with a religious background. Suicide attempters, who should be expected to have a higher rate of psychopathology according to Greyson (1991) did not show much difference from non-suicides in the frequency of NDEs. Bush (2012), holds that frightening NDEs have been ignored too long, in favor of only positive reports: "In fact, because contemporary metaphysical thought has so strongly emphasized the belief (or certainly the hope) that only the light is real and has value, it has by and large denied or ignored the 'dark night' aspects of spirituality."
Negative or distressing NDEs
Lindley, Bryan and Conley (1981) in a study of 55 near-death encounters found eleven (20 percent) to be "partially negative or Hellish." They defined a "negative" near death experience as one that contains extreme fear, panic or anger. It may also contain descriptions of demonic creatures or embittered human-like voices that mock or taunt the subjects. Such negatives may only form part of the overall NDE incident. Margot Grey's study of NDEs in England (Grey 1985) reports that distressing experiences tend to follow 5 phases: fear and panic, out of body experience, entering a black void, sensing an evil force and entering a hellish environment. These 5 phases parallel the more typical "standard" NDEs of peace, out of body experience, tunnel travel, seeing the light, and entrance to the paradise environment. Distressing experiences were more likely to be reported shortly after the NDE incident than the positive experiences.
Grey's comparative study of British and American near-death experiencers indicates that negative features, while a small minority, definitely exist. Typical negative experiences described by subjects include feelings of panic, anguish, desperation, intense loneliness and desolation. Subjects described environments as either dark and gloomy or barren and hostile; some subjects reported being on the brink of a pit or abyss, or sensing evil or malevolent forces or creatures. Such environments were sometimes conceived of by subjects as intensely hot or cold and often included sounds of despair or mourning. Atwater (1988) also noted patterns parallel to peaceful NDEs in her study including lifeless apparitions, barren expanses, threats or silence, a seeming danger of violence, a sense of hell and coldness. Flynn (1986) notes a general pattern to distressing experiences in which evil or darkness is experienced as a distinct dimension or entity separate from the positively experienced light. Atwater (1992) reports that only adults in her sample experienced distressing NDEs, not children.
Three patterns of distressing NDEs. Greyson and Bush's (2013) analysis of 50 distressing NDEs, report the following 3 patterns:
- Level one: Experience of certain "typical" NDE features that were interpreted as terrifying. Features such as out of body travel, meeting of persons on "the other side", barriers that separated certain zones from others, etc. were experienced negatively rather than positively, usually from a sense of lack of control.
- Level two: A second pattern of distressing NDE experiences was an experience of nothingness or of existing in an eternal, featureless void. This experience sometimes included a sense of despair, that earthly life itself had been a cruel illusion or joke. Sometimes this sense is amplified by bitter, raging entities similarly suspended in the darkness of the void, who maliciously jeer and taunt the subject, suggesting that they never even existed. Subjects felt trapped, with all they had known before gone, and a sense of trying to prove existence, that now seemed meaningless in the endless gloom.
- Level three: The third pattern was explicit hellish images sometimes involving foreboding or menacing landscapes, a sense of falling down a dark abyss, which had levels filled with scenes of mourning, wailing, despair, or threat by a hostile presence similarly situated in the more intense or abysmal location. The dark or menacing entities who pursued or taunted the NDEr might be perceived as raging or embittered human souls or some other entity, and appeared real to the NDE traveler. Few explicit accounts of horned imps, devils, pitchforks, physical torture or other such elements of hell from popular culture appear however. In some cases, supposedly trapped souls endure tormenting "fire" or "flame"- the tormenting "fire" not being physical, but moral, in the form of remorse or anguish at their own choices, behaviors or attitudes, agony or regret at being separated from the Light or Light Being, or frustration at the inability to satisfy earthly obsessions brought into death.
Moral dimensions of distressing NDEs. A number of writers on Near Death Experiences identify a dark zone or "void" in association with negative or malignant spiritual beings, or a zone of despair, depression or despondency connected with the actions persons have committed in earthly life or their moral character. These negative elements may not be isolated but may blend with other standard NDE features. NDErs who have viewed a "dark" void of depressed or trapped "souls" for example, may still go on to have a Life Review, feeling of warmth and love, and other such elements. The Life Review NDE accounts detail is usually a time of searching exposure and affirmation, having moral implications that the NDE traveler had to confront, including his or her actions and the negative or positive impact they had on others. Some New Age writers like Edgar Cacye and Emmanuel Swedenborg also identify a dark or negative area brought about by the dead person's own behavior, state or obsessions in their earthly physical life. According to Swedenborg: "All who are in the Hells are in evils and in falsities therefrom derived from the loves of self and of the world" (n. 551-565).
This aspect of the Life Review is sometimes described as humbling with inward character, thoughts and outward actions laid bare, and the subject invited to examine how wrong (or right) they were through the eyes of the Divine/Light Being, and how others were affected. While the exposure was felt as distressing in some aspects, the Review is generally in a larger context of being unconditionally loved, though regret and guilt may be experienced. NDErs under the full moral exposure of the Review almost always agreed with the Divine Being as to rightness or wrongness of their actions, as seen through the Being's moral perspective, and the rightness of that perspective. The Being of Light or others may later make clear to the NDE that they are in a temporary transitional not permanent state and must choose to "go back" or "stay". Sometimes the NDEr is told that a "work" or life must be completed. The final moral destiny or fate of the "returning" NDEr is thus pushed back to some future time.
In the 1990s a literature on distressing near-death experiences emerged. One cardiologist (Maurice Rawlins) describes a patient fading in and out of consciousness screaming "I am in hell." The patient later described near-death phenomena but without recalling the hellish aspect. Both doctor and patient were transformed by the experience, each becoming religious. Medical patients appear more likely to forget such frightening experiences than pleasant ones, or may be more reluctant to share negative self-images and memories than positive ones with researchers. According to one study of NDEs- most contemporary near-death experiencers recount that they, not the Light Being perform the moral judgment, their own consciences holding them accountable. The "Figure of Light" serves to provide the standard of judgment. A recurring theme in Life Reviews is that each person is responsible for every thought, word and deed of his or her life. Bush (2012) holds that the notion of being prepared may apply if consciousness is not strictly in the human brain:
- "This concept is part of a much larger conversation involving the growing evidence that consciousness is not strictly located in the brain but has a much greater field, perhaps universe-wide. That being true, it seems likely that the better prepared we are for these kinds of experience, the happier will be the outcome."
Distressing NDE patterns and outcomes. Rommer (2001) found that NDE suicide attempters made up 55% of people in her research who reported a Type II Eternal Void experience, 18% who reported a Type III Hellish experience, and most of those who reported a Type IV Negative Judgment experience, but cautions against jumping to conclusions about suicides since some suicide NDEs are pleasurable, and the emotional turmoil surrounding the suicide event, and/or guilt or fear about the negative consequences for suicides on the other side may play a part in influencing the pattern of these experiences. NDErs who experience distressing experiences may often turn around their lives in a positive way, or attempt to do so. Rommer 2001 suggests that distressing NDErs almost always come to see their experiences as blessings in disguise. Bush (2002) holds that "returning" NDErs have a more mixed pattern of post-event edjustment- with those who interpret the experience as a warning to correct previous behaviors healing most quickly and thoroughly. Others may attempt to dismiss the experience as less valid than pleasurable NDEs, or may take a long view, sometimes lasting years, to draw lessons and conclusions from the NDE experience.
A small percentage of NDE subjects report a prophetic vision that reveals to them the fate of earth and humanity. This is generally an apocalyptic vision showing the end times, but some report visions of humanity evolving into higher beings. Although some claim to have specific forecasts such as the time of a big natural disaster, most NDErs who allege messages or prophecies do not proffer specific information on future world events, save in a general way: such as warning mankind that it is accountable on the other side, a vague coming period of war and chaos, or to turn from environmental destruction or mistreatment of one another, or the vast new realm of light and love beyond physical death. Some prophecies are of a personal nature, such as children that will be born in the future, or the pending death of a relative. Other prophecies are limited to the personal testimony of the NDE, as to the felt reality of the experience, the future of light and hope, or the ethical, moral or religious lessons to be drawn, rather than sweeping claims as to specific future historical incidents.
Messages said to be given sometimes occur during the Life Review, where the NDEr is given a detailed "playback" exposing all thoughts, actions and motives and their impact, as seen through the moral and spiritual lens of the Being of Light. The personal future or outcome of the temporary NDE sojorner is sometimes left ambiguous. A Life Review may confirm personal safety, protection or salvation upon future death, or may leave the future open until the normal termination of earthly life. Some NDE travelers may conceive of Life Reviews as a "reprieve" or a "second chance" to put things right in their lives, before they cross over the other side of death, since all actions and thoughts are to be accountable there. NDErs generally are changed by their experience, becoming less ego-centric, more empathetic, and having less interest in status symbols and material possessions.
In the process of clinical death, the heart stops working and pumping blood to the brain, thereby cutting the brain's essential supply of oxygen and of other less urgent nutrients. Some studies in humans and animals have shown that after a very short time (10 - 20 seconds) brain function as measured by EEG ceases. And during brain death, all brain function permanently ceases. As characteristic of all biological cells, brain cells die once deprived of oxygenated blood, destroying the brain. According to the current mainstream neuroscientific view, the mind fails to survive brain death and ceases to exist.
Because the study of NDEs is a topic that addressed multiple possible feelings, sensations and their origins, research on NDE should be conducted primarily by researchers with credentials in cognitive neuroscience. Cognitive neuroscience addresses the questions of how psychological functions (for example, human feelings and sensations) are produced by neural circuitry (including the human brain). Modern contributions to the research on near-death experiences, however, have come from several academic disciplines that generally do not include neuroscience. There are multiple reasons for this trend. For example, brain activity scans are not typically performed when a patient is undergoing attempts at emergency resuscitation. Claiming that there is no measurable brain activity without having a variety of different EEG, catSCAN, FMRI, etc. is not considered a good scientific practice. Existing research is mainly in the disciplines of medicine, psychology and psychiatry. Heightened brain activity has been recorded in experimental rats directly following cardiac arrest though there has been no similar research in humans.
Individual cases of NDEs in literature have been identified into ancient times. In the 19th century a few efforts moved beyond studying individual cases - one privately done by Mormons and one in Switzerland. Up to 2005, 95% of world cultures have been documented making some mention of NDEs.
Contemporary interest in this field of study was originally spurred by the writings of Jess Weiss (popular literature author), Elisabeth Kübler-Ross (psychiatrist), George Ritchie (psychiatrist), and Raymond Moody Jr. (psychologist and M.D.). Moody's book Life After Life, which was released in 1975, brought public attention to the topic of NDEs. This was soon to be followed by the establishment of the International Association for Near-death Studies (IANDS) in 1981. IANDS is an international organization that encourages scientific research and education on the physical, psychological, social, and spiritual nature and ramifications of near-death experiences. Among its publications are the peer-reviewed Journal of Near-Death Studies and the quarterly newsletter Vital Signs.
Bruce Greyson (psychiatrist), Kenneth Ring (psychologist), and Michael Sabom (cardiologist), helped to launch the field of Near-Death Studies and introduced the study of near-death experiences to the academic setting. From 1975 to 2005, some 2500 self reported individuals in the US had been reviewed in retrospective studies of the phenomena with an additional 600 outside the US in the West, and 70 in Asia. Prospective studies, reviewing groups of individuals and then finding who had an NDE after some time and costing more to do, had identified 270 individuals. In all close to 3500 individual cases between 1975 and 2005 had been reviewed in one or another study. And all these studies were carried out by some 55 researchers or teams of researchers. The medical community has been reluctant to address the phenomenon of NDEs, and grant money for research has been scarce. Nevertheless, both Greyson and Ring developed tools usable in a clinical setting. Major contributions to the field include Ring's construction of a "Weighted Core Experience Index" to measure the depth of the near-death experience, and Greyson's construction of the "Near-death experience scale" to differentiate between subjects that are more or less likely to have experienced an NDE. The latter scale is also, according to its author, clinically useful in differentiating NDEs from organic brain syndromes and nonspecific stress responses. The NDE-scale was later found to fit the Rasch rating scale model. Greyson has also brought attention to the near-death experience as a focus of clinical attention, while Melvin Morse, head of the Institute for the Scientific Study of Consciousness, and colleagues have investigated near-death experiences in a pediatric population.
Neurobiological factors in the experience have been investigated by researchers in the field of medical science and psychiatry. Among the researchers and commentators who tend to emphasize a naturalistic and neurological base for the experience are the British psychologist Susan Blackmore (1993), with her "dying brain hypothesis", and the founding publisher of Skeptic magazine, Michael Shermer (1998). More recently, cognitive neuroscientists Jason Braithwaite (2008) from the University of Birmingham and Sebastian Dieguez (2008) and Olaf Blanke (2009) from the Ecole Polytechnique Fédérale de Lausanne, Switzerland have published accounts presenting evidence for the brain-based nature of near death experiences.
In September 2008, it was announced that 25 U.K. and U.S. hospitals would examine near-death studies in 1,500 heart attack patient-survivors. The three-year study, coordinated by Sam Parnia at Southampton University, hopes to determine if people without heartbeat or brain activity can have an out-of-body experience with veridical visual perceptions. This study follows on from an earlier 18-month pilot project. On a July 28, 2010 interview about a recent lecture at Goldsmiths, Parnia (internal medicine physician by training with specialty in pulmonology, critical care, and sleep medicine) asserts that "evidence is now suggesting that mental and cognitive processes may continue for a period of time after a death has started" and describes the process of death as "essentially a global stroke of the brain. Therefore like any stroke process one would not expect the entity of mind / consciousness to be lost immediately". He also expresses his disagreement with the term 'near death experiences' because "the patients that we study are not near death, they have actually died and moreover it conjures up a lot of imprecise scientific notions, due to the fact that [death] itself is a very imprecise term".
Researcher Lakhmir Chawla, an Associate Professor of Anesthesiology and Critical Care Medicine and Medicine at George Washington University medical centre in Washington D.C. argues that near-death experiences are caused by a surge of electrical activity as the brain runs out of oxygen before death. Levels were similar to those seen in fully conscious people, even though blood pressure was so low as to be undetectable, and could generate vivid images and feelings. The gradual loss of brain activity had occurred in the approximate hour before death, and was interrupted by a brief spurt of action, lasting from 30 seconds to three minutes. Sam Parnia disputed this explanation, claiming that Lakhmir Chawla had not provided proof that the electrical surges he recorded were linked to near-death experiences, saying: "Since all the patients died, we cannot tell what they were experiencing".
The top peer-reviewed journals in neuroscience, such as Nature Reviews Neuroscience, Brain Research Reviews, Biological Psychiatry, Journal of Cognitive Neuroscience are generally not publishing research on NDEs. Among the scientific and academic journals that have published, or are regularly publishing, new research on the subject of NDEs are Journal of Near-Death Studies, Journal of Nervous and Mental Disease, British Journal of Psychology, American Journal of Disease of Children, Resuscitation, The Lancet, Death Studies, and the Journal of Advanced Nursing.
Variance in NDE studies
The prevalence of NDEs has been variable in the studies that have been performed. According to the Gallup and Proctor survey in 1980-1981, of a representative sample of the American population, data showed that 15% had an NDE. Knoblauch in 2001 performed a more selective study in Germany and found that 4% of the sample population had an NDE. The information gathered from these studies may nevertheless be subject to the broad timeframe and location of the investigation.
Perera et al., in 2005, conducted a telephone survey of a representative sample of the Australian population, as part of the Roy Morgan Catibus Survey, and concluded that 8.9% of the population had an NDE. In a more clinical setting, van Lommel et al. (2001), a cardiologist from Netherlands, studied a group of patients who had suffered cardiac arrests and who were successfully revived. They found that 62 patients (18%) had an NDE, of whom 41 (12%, or 66% of those who had an NDE) described a core experience.
According to Martens the only satisfying method to address the NDE-issue would be an international multicentric data collection within the framework for standardized reporting of cardiac arrest events. The use of cardiac-arrest criteria as a basis for NDE research has been a common approach among the European branch of the research field.
Biological analysis and theories
The first formal neurobiological model for NDE was presented in 1987 by Chilean scientists Juan Sebastián Gómez-Jeria (who holds a PhD in Molecular Physical Chemistry) and Juan Carlos Saavedra-Aguilar (M.D.) from the University of Chile. In the 1990s, Rick Strassman conducted research on the psychedelic drug dimethyltryptamine (DMT) at the University of New Mexico. Strassman advanced the hypothesis that a massive release of DMT from the pineal gland prior to death or near-death was the cause of the near-death experience phenomenon. Only two of his test subjects reported NDE-like aural or visual hallucinations, although many reported feeling as though they had entered a state similar to the classical NDE. His explanation for this was the possible lack of panic involved in the clinical setting and possible dosage differences between those administered and those encountered in actual NDE cases. All subjects in the study were also very experienced users of DMT and/or other psychedelic/entheogenic agents. Some speculators consider that if subjects without prior knowledge on the effects of DMT had been used during the experiment, more volunteers would have reported NDE. Critics have argued that neurobiological models often fail to explain NDEs that result from close brushes with death, where the brain does not actually suffer physical trauma, such as a near-miss automobile accident. Such events may however have neurobiological effects caused by stress.
Whether or not these experiences are hallucinatory, they have a profound impact on the observer. Many psychologists not necessarily pursuing the paranormal, such as Susan Blackmore, have recognized this, and seek its biological cause.
According to Engmann (medical doctor), near-death experiences of people who are clinically dead are psychopathological symptoms caused by a severe malfunction of the brain resulting from the cessation of cerebral blood circulation. An important question is whether it is possible to "translate" the bloomy experiences of the reanimated survivors into psychopathologically basic phenomena, e.g. acoasms, central narrowing of the visual field, autoscopia, visual hallucinations, activation of limbic and memory structures according to Moody's stages. The symptoms suppose a primary affliction of the occipital and temporal cortices under clinical death. This basis could be congruent with the thesis of pathoclisis—the inclination of special parts of the brain to be the first to be damaged in case of disease, lack of oxygen, or malnutrition—established eighty years ago by Cécile and Oskar Vogt. According to that thesis, the basic phenomena should be similar in all patients with near-death experiences. But a crucial problem is to distinguish these basic psychopathological symptoms from the secondary mental associated experiences which may result from a reprocessing of the basic symptoms under the influence of the person's cultural and religious views.
Research released in 2010 by University of Maribor, Slovenia had put near-death experiences down to high levels of carbon dioxide in the blood altering the chemical balance of the brain and tricking it into 'seeing' things. Of the 52 patients, 11 reported NDEs. Neuropsychiatrist Peter Fenwick of the Institute of Psychiatry at Kings College London responded to this study with "in cardiac arrests, everybody has high CO2 but only 10 percent have NDEs," and "What's more, in heart attack patients, Fenwick said, "there is no coherent cerebral activity which could support consciousness, let alone an experience with the clarity of an NDE."
An article by Dutch cardiologist Pim van Lommel et al., argues, "With a purely physiological explanation such as cerebral anoxia for the experience, most patients who have been clinically dead should report one." Accordingly, a lack of predictable experiences should cast doubt on wholesale explanations of NDEs. According to Southampton University researcher Sam Parnia (critical care doctor), "Death starts when the heart stops beating, but we can intervene and bring people back to life, sometimes even after three to four hours when they are kept very cold. It could be that a far higher proportion of people have near-death experiences but don't remember them."
Psychologist Christopher C. French has summarized psychological and organic theories that provide an existing scientific explanation for NDEs. Psychological include the proposal that the NDE is a dissociative defense mechanism that occurs in times of extreme danger. A wide range of organic theories of the NDE has been put forward including those based upon cerebral hypoxia, anoxia, and hypercarbia; endorphins and other neurotransmitters; and abnormal activity in the temporal lobes. NDE subjects have increased activity in the left temporal lobe. In an experiment with one patient, electrical stimulation at the left temporoparietal junction lead to an illusion of another person close to her.
It is suggested that the extreme stress caused by a life-threatening situation triggers brain states similar to REM sleep and that part of the near death experience is a state similar to dreaming while awake. People who have experienced times when their brains behaved as if they were dreaming while awake are more likely to develop the near death experience.
Some sleep researchers, such as Timothy J. Green, Lynne Levitan and Stephen LaBerge, have noted that NDE experiences are similar to many reports of lucid dreaming, in which the individual realizes he is in a dream. Often these states are so realistic as to be barely distinguishable from reality.
In a study of fourteen lucid dreamers performed in 1991, people who perform wake-initiated lucid dreams (WILD) reported experiences consistent with aspects of out-of-body experiences such as floating above their beds and the feeling of leaving their bodies. Due to the phenomenological overlap between lucid dreams, near-death experiences, and out-of-body experiences, researchers say they believe a protocol could be developed to induce a lucid dream similar to a near-death experience in the laboratory.
Other similarities include seeing oneself from the outside (an out of body experience), floating or flying, heightened awareness, and feelings of joy or peace. Some researchers believe this is caused when the mind is deprived of the majority of its senses and relies on the expectational processing. In this regard one experiences what one would expect to happen in their current circumstance. This could explain experiences caused by mental trauma such as a near miss accident in which the mind may close itself off at least partially to the senses and ones caused by physical trauma in which again the mind closes itself off to the world. At present, there exists no clear physiological or psychological basis for any relationship between lucid dreaming and NDEs.
Modeling of NDEs by S. L. Thaler in 1993  using artificial neural networks has shown that many aspects of the core near-death experience can be achieved through simulated neuron death. In the course of such simulations, the essential features of the NDE—life review, novel scenarios (i.e., heaven or hell), and OBE—are observed through the generation of confabulations or false memories, as discussed in Confabulation (neural networks). The key feature contributing to the generation of such confabulatory states are a neural network's inability to differentiate dead from silent neurons. Memories, whether related to direct experience, or not, can be seeded upon arrays of such inactive brain cells.
Van Lommel studies
The first clinical study of near-death experiences (NDEs) in cardiac arrest patients was by Pim van Lommel, a cardiologist from the Netherlands, and his team (The Lancet, 2001). Of 344 patients who were successfully resuscitated after suffering cardiac arrest, 62 (18%) expressed an intraoperative memory and among these, 41 (12%) experienced core NDEs, which included out-of-body experiences. According to Lommel, the patients remembered details of their conditions during their cardiac arrest despite being clinically dead with flatlined brain stem activity. Van Lommel concluded that his findings supported the theory that consciousness continued despite lack of neuronal activity in the brain. Van Lommel conjectured that continuity of consciousness may be achievable if the brain acted as a receiver for the information generated by memories and consciousness, which existed independently of the brain, just as radio, television and internet information existed independently of the instruments that received it.
Van Lommel et al., reported that 62 of the 344 patients with cardiac arrest reported some recollection. Of these 62, 50% reported an awareness or sense of being dead, 24% said that they had had an out-of-body experience, 31% recalled moving through a tunnel, whilst 32% described meeting with deceased people. Moreover, while near-death experiencers commonly report feelings of peace and bliss, only 56% associated the experience with such positive emotions. No patients reported a distressing or frightening NDE.
NDEs are also associated with changes in personality and outlook on life. Kenneth Ring (professor of psychology) has identified a consistent set of value and belief changes associated with people who have had a near-death experience. Among these changes one finds a greater appreciation for life, higher self-esteem, greater compassion for others, a heightened sense of purpose and self-understanding, desire to learn, elevated spirituality, greater ecological sensitivity and planetary concern, and a feeling of being more intuitive. Changes may also include increased physical sensitivity; diminished tolerance of light, alcohol, and drugs; a feeling that the brain has been "altered" to encompass more; and a feeling that one is now using the "whole brain" rather than a small part. However, not all after-effects are beneficial and Greyson describes circumstances where changes in attitudes and behavior can lead to psychosocial and psychospiritual problems. Often the problems are those of the adjustment to ordinary life in the wake of the NDE.
Recent research into afterlife conceptions across cultures by religious studies scholar Gregory Shushan  analyzes the afterlife beliefs of five ancient civilizations (Old and Middle Kingdom Egypt, Sumerian and Old Babylonian Mesopotamia, Vedic India, pre-Buddhist China, and pre-Columbian Mesoamerica) in light of historical and contemporary reports of near-death experiences, and shamanic afterlife "journeys". It was found that despite numerous culture-specific differences, the nine most frequently recurring NDE elements also recur on a general structural level cross-culturally, as if to suggest that the authors of these ancient religious texts were familiar with NDE or similar. Cross-cultural similarity, however, can be used to support both religious and physiological theories, for both rely on demonstrating that the phenomenon is universal. Others dispute in favor of cultural similarities; and others suggest that the experience is essentially universal, but altered in detail by cultural bias.
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Many individuals who experience an NDE see it as a verification of the existence of life after death, and several researchers in the field of near-death studies see the NDE as evidence that strongly suggest that human consciousness may continue to exist after physical death.
Skeptics argue against the false deduction that a patients brain in clinical death is completely inactive and that the memory of the NDE experience latter reported by the experiencer was formed during that time. Most brain activity tests are not typically performed when a patient is undergoing attempts at emergency resuscitation because this takes far too much time, and patients need to be resuscitated as soon as possible. It is entirely possible, for example, that a patient showing no activity on an EEG scan could still have brain activity that would appear on an FMRI, PET, or catSCAN. This is because, unless surgically implanted into the brain directly, the EEG principally measures surface cortical activity. NDE researcher Pim van Lommel argues that this objection "misses the mark", "the issue is not whether there is any non-measurable brain activity of any kind whatsoever, but whether there is measurable brain activity of the specific form, and in different neural networks, as regarded by contemporary neuroscience as the necessary condition of conscious experience."
It's very difficult to verify the timing of memory formation relative to brain scans when the patient is not conscious. The only way is for the memories to contain specific details that could only have been obtained during that time.
Also, the experiences reported by NDE subjects have also been reported by other patients whose experiences had known triggers (mostly chemicals of a psychedelic nature.) The chemical processes that happen in a brain under oxygen deprivation are known to share some characteristics with the effects of psychoactive substances.
Personal experiences (self-reported)
- Return from Tomorrow by George G. Ritchie with Elizabeth Sherrill (1978). At the age of 20, George Ritchie died in an army hospital. Nine minutes later he returned to life. Ritchie's story was the first contact Raymond Moody (who was studying at the University of Virginia, as an undergraduate in Philosophy, at the time) had with NDEs. It inspired Moody to investigate over 150 cases of near-death experiences, in his book Life After Life, and two other books that followed.
- Embraced by the Light by Betty Eadie (1992). One of the most detailed near-death experiences on record.
- Saved by the Light by Dannion Brinkley. Brinkley's experience documents one of the most complete near death experiences, in terms of core experience and additional phenomena from the NDE scale. Brinkley claims to have been clinically dead for 28 minutes and taken to a hospital morgue, but some of his claims are disputed.
- Placebo by Howard Pittman (1980). A detailed record of Pittman's near-death experience.
- The Darkness of God by John Wren-Lewis (1985). Bulletin of the Australian Institute for Psychical Research No 5. An account of the effects of his NDE after going through the death process several times in one night.
- Two have associated their experiences with their decision to join the Bahá'í Faith: Reinee Pasarow and Ricky Bradshaw, whose story has been reviewed in several books.
- Anita Moorjani, an ethnic Indian woman from Hong Kong, experienced a NDE which has been documented on the Near Death Experience Research Foundation (NDERF) website as one of the most exceptional accounts on their archives. She had end-stage cancer and on February 2, 2006, doctors told her family that she only had a few hours to live. Following her NDE, Anita experienced a remarkable recovery of her health.
- Goldie Hawn, while giving a speech at the Buell Theater in Denver, Colorado, reflected upon her near-death experience. When she was younger, and starting out as an actress, she and a group of friends were in a severe car crash together. While she was unconscious, she remembers looking over herself while the paramedics were trying to revive her. She also mentioned seeing a bright light and being told it was not her time soon before she awoke.
- Kiki Carter, a.k.a. Kimberli Wilson, an environmental activist and singer/songwriter, reported a near-death experience in 1983. The day after the experience, her mother, Priscilla Greenwood, encouraged her to write it down. Priscilla Greenwood published the story in September 1983 in a local metaphysical journal. For 24 hours after the experience, Kimberli had an aftervision which was a catalyst for her interest in quantum physics and holograms.
- 90 Minutes in Heaven by Don Piper, is Piper's account of his own near-death experience. EMTs on the scene determined Piper had been killed instantly after a tractor-trailer had swerved into his lane, crushing his car. Piper survived, however. In the book, he wrote about seeing deceased loved ones and friends as well as magnificent light; he felt a sense of pure peace. Piper had a very difficult and painful recovery, undergoing 34 surgeries.
- Heaven Is for Real by Todd Burpo, is a father's account of his son, Colton, and Colton's trip to heaven and back. After discovering that then-four-year-old Colton's appendix has ruptured, he was rushed to the hospital. While unconscious, Colton describes having met Jesus, God, his great-grandfather whom he had never met, and his older sister lost in a miscarriage.
- Parallel Universes, a Memoir from the Edges of Space and Time by Linda Morabito Meyer is a NASA scientist's account of several near death experiences at the hands of her parents and William Franklin Mosley of the Temple of the More Abundant Life in Vancouver, British Columbia, Canada. She explained that during these experiences, she visited Heaven, saw Jesus, and was in the presence of God.
- Eben Alexander, M.D., born December, 1953, author of Proof of Heaven: A Neurosurgeon's Journey into the Afterlife, which made The New York Times Best Seller list for nonfiction. In the book, Alexander describes how he had an intense NDE while in a seven-day coma brought on by an attack of meningitis.
- The Friend From Mexico, a True Story of Surviving an Intensive Care Unit (2012) by Apostolos Mavrothalassitis is the author's near-death experience account. Following a mid-air collision while participating in the 2009 Paragliding World Championships, he suffered extensive blood loss during surgery and was put under induced coma for two weeks. During these two weeks he lived a different life, and was not aware of his predicament. The experiences during this period are described in the book.
- Howard Storm. In 1985, Storm travelled to Europe with his wife and university students. After suffering from severe stomach pain, he ended up in a hospital in Paris, where he had a near death experience.
- Curtis "Earthquake" Kelley experienced a near death experience after a drug overdose.
- Josh Homme of Queens of the Stone Age elaborated on his near-death experience in an interview with Marc Maron in October 2013. He told Maron that he contracted a methicillin-resistant Staphylococcus aureus (MRSA) infection in 2010, which his immune system could not fight due to stress. Due to unexpected complications during knee surgery, the doctors could not oxygenate his blood, and Josh suffered a near death experience due to asphyxiation. Doctors eventually had to use a defibrillator to revive him. Following this, he was confined to bed rest for three months. The experience left him weakened and unable to produce music for almost two years.
- Beyond and Back
- Deathbed phenomena
- Form constant
- Lazarus phenomenon
- Near-death studies
- Beauregard, Mario; Denyse O'Leary (2007). "Toward a Nonmaterialist Science of Mind". The Spiritual Brain. New York: HarperOne. p. 368. ISBN 978-0-06-085883-4.
- Buzzi, Giorgio. "Correspondence: Near-Death Experiences." Lancet. Vol. 359, Issue 9323 (June 15, 2002): 2116-2117.
- Britton, Willoughby B. and Richard R. Bootzin. "Near-Death Experiences and the Temporal Lobe." Psychological Science. Vol. 15, No. 4 (April 2004): 254-258.
- Blackmore, Susan: Dying to Live: Near-Death Experiences (1993). London, Grafton.
- Grossman, Neil (Indiana University and University of Illinois), Who's Afraid of Life After Death? Why NDE Evidence is Ignored, Institute of Noetic Sciences (IONS), 2002
- Fontana, David (Cardiff University and Liverpool John Moores University), Does Mind Survive Physical Death?, 2003
- London Telegraph, 10/22/2000 article: Soul-searching doctors find life after death, about Drs. Peter Fenwick and Sam Parnia studies of heart attack survivors
- Carter, Chris: Science and the Near-Death Experience: How Consciousness Survives Death (2010). Toronto, Inner Traditions. ISBN 1-59477-356-4
- "Characteristics of Near-Death Experiences Memories as Compared to Real and Imagined Events Memories". PLOS ONE. 2013. Retrieved 14 April 2013.
- Moody, R. (1975) Life After Life: The Investigation of a Phenomenon - Survival of Bodily Death. New York: Bantam
- Duane S. Crowther (2005). Life Everlasting Cedar Fort, p. 19.
- IANDS. "Near-Death Experiences: Is this what happens when we die?" Durham: International Association for Near-Death Studies. Informational brochure available at www.iands.org
- Mauro, James "Bright lights, big mystery".Psychology Today, July 1992.
- Simpson SM. (2001) Near death experience: a concept analysis as applied to nursing. Journal of Advanced Nursing. Nov;36(4):520-6. PubMed abstract PMID 11703546
- Lange R, Greyson B, Houran J. (2004) "A Rasch scaling validation of a 'core' near-death experience". British Journal of Psychology, Volume: 95 Part: 2 Page: 161-177
- Greyson, Bruce (2003), "Near-Death Experiences in a Psychiatric Outpatient Clinic Population", Psychiatric Services, Dec., Vol. 54 No. 12. The American Psychiatric Association.
- van Lommel, Pim (Hospital Rijnstate),"A Reply to Shermer: Medical Evidence for NDEs" in Skeptical Investigations, 2003. 
- van Lommel P, van Wees R, Meyers V, Elfferich I. (2001) "Near-Death Experience in Survivors of Cardiac Arrest: A prospective Study in the Netherlands" in The Lancet, December 15; 358(9298):2039-45. PDF version of article
- Pim van Lommel (2010). Consciousness Beyond Life: The science of the near-death experience. HarperOne. p. 28. ISBN 978-0-06-177725-7.
- Evelyn Elsaesser Valarino (1997). On the Other Side of Life: Exploring the phenomenon of the near-death experience. Perseus Publishing. p. 203. ISBN 0-7382-0625-3.
- Egger, Victor (1896). « Le moi des mourants », Revue Philosophique, XLI : 26-38.
- J. Bogousslavsky, M. G. Hennerici, H Bazner, C. Bassetti (Eds.) (2010). Neurological Disorders in Famous Artists, Part 3. Karger Publishers. p. 189.
- Green, C., Out-of-the-body Experiences, London: Hamish Hamilton, 1968.
- Mauro, James. "Bright lights, big mystery", Psychology Today, July 1992.
- Greyson, Bruce (2003) "Near-Death Experiences in a Psychiatric Outpatient Clinic Population". Psychiatric Services, December, Vol. 54 No. 12. The American Psychiatric Association
- van Lommel P, van Wees R, Meyers V, Elfferich I. (2001) "Near-Death Experience in Survivors of Cardiac Arrest: A prospective Study in the Netherlands," The Lancet, December 15; 358 (9298):2039-45. Table 2.
- IANDS Near-Death Experiences: Is this what happens when we die? Durham: International Association for Near-Death Studies.
- Morse M., Conner D. and Tyler D. (1985) "Near-Death Experiences in a pediatric population. A preliminary report", American Journal of Disease of Children, n. 139 PubMed abstract PMID 4003364
- Ring, K. (1980). Life at death: A scientific investigation of the near-death experience. New York: Coward, McCann, & Geoghegan., p. 40
- Kenneth Ring, quoted in Ketamine - Near Death and Near Birth Experiences Dr Karl Jansen
- van Lommel P, van Wees R, Meyers V, Elfferich I. (2001) "Near-Death Experience in Survivors of Cardiac Arrest: A prospective Study in the Netherlands" in The Lancet, December 15; 358(9298):2039-45. Page 2039
- Ring, Kenneth. Heading toward Omega. In search of the Meaning of Near-Death Experience, 1984, p. 45. "Subsequent research on suicide-related NDEs by Stephen Franklin and myself [Ring] and by Bruce Greyson has also confirmed my earlier tentative findings the NDEs following suicide attempts, however induced, conform to the classic prototype."
- Greyson, Bruce & Bush, Nancy E. (1992) "Distressing near-death experiences". Psychiatry, Feb; 55(1):95-110.
- Culture and NDEs
- The Natural Death Handbook - Varieties of NDE
- Lindley, JH; Bryan, S & Conley, B, 'Near-death experiences in a Pacific Northwest population: The Evergreen study – Anabiosis 1. p109, 1981
- Raymond Moody, 1988. The Light Beyond, pp. 29-64; Howard Storm (2005). My Descent Into Death: A Second Chance at Life, 19-57, 131-133
- Bruce Greyson 2006. Near-Death Experiences and Spirituality. Zygon 41:2 393-414
- Greyson Bruce, 2007. Consistency of near-death experience accounts over two decades: are reports embellished over time? Resuscitation (2007) 73, 407—411.
- Nancy Bush (2012) Dancing Past the Dark; Greyson and Nancy Bush (1992) Distressing Near-Death Experiences, Psychiatry 55: 95-109
- Greyson, Bruce (1991) "Near-Death Experiences Precipitated by Suicide Attempt." Journal of Near Death Studies, 9(3)
- Nancy Bush (2012) Dancing Past the Dark. p 123
- Margot Grey. 1985. American Society for Psychical Research. Return From Death: An Exploration of the Near-Death Experience, London, England: Arkana, 1985
- Lee Bailey, Jenny Yates (1023). The Near Death Experience: A Reader, pp 210-214
- Atwater, P.M.H. (1992). Is There a Hell? Journal of Near-Death Studies, 10(3).
- Greyson and Bush's (2013) "Distressing Near Death Experiences" in Lee Bailey, Jenny Yates (2013). The Near Death Experience: A Reader, pp 210-214
- "Swedenborg, E. Heaven and its Wonders and Hell. From Things Heard and Seen (Swedenborg Foundation, 1946)".
- Bruce Greyson 2006. Near-Death Experiences and Spirituality. Zygon 41:2 393-414; Atwater, P.M.H. (1992). Is There a Hell? Surprising Observations About the Near-Death Experience. Journal of Near-Death Studies, 10(3).
- Greyson, 2006, 393-414
- Robert Grant 1996. Edgar Cayce on Angels, Archangels and the Unseen Forces. pp 82-139
- Swedenborg, E. Heaven and its Wonders and Hell. From Things Heard and Seen (Swedenborg Foundation, 1946)". Swedenborgdigitallibrary.org. Retrieved 2013-01-13.
- Swedenborg, 576-581;551-565
- Moody 1975, Greyson, 2006, 393-414; Yates and Bailey, 2013
- Elie Kaplan Spitz. 2002 Does the Soul Survive?: A Jewish Journey to Belief in Afterlife, Past Lives. 137-142
- Spitz, 2002
- Nancy Bush (2012) Dancing Past the Dark. p 200
- Rommer, B. (2000). Blessing in Disguise: Another Side of the Near-Death Experience. St. Paul, MN: Llewellyn.
- Rommer 2001
- Bush, N. E. (2002). "Afterward: Making meaning after a frightening near-death experience". Journal of Near-Death Studies 21(2), pp. 99-133.
- Janice Holden, Bruce Greyson, Debbie James. 2009. The Handbook of Near-Death Experiences: Thirty Years of Investigation. 17-152; Bailey and Yates, pp 135-214
- Spitz 2002, Does the Soul Survive..pg 6
- Holden, Greyson and James, 17-152; Moody 1975
- Howard Storm (2005). My Descent Into Death: A Second Chance at Life, 19-57, 131-133
- "Pim van Lommel - Consciousness Beyond Life: The Science of the Near-Death Experience"
- Piccinini, Gualtiero; Bahar, Sonya. "No Mental Life after Brain Death: The Argument from the Neural Localization of Mental Functions" (2011). University of Missouri - St. Louis.
- Bernat JL (8 Apr 2006). "Chronic disorders of consciousness". Lancet 367 (9517): 1181–1192. doi:10.1016/S0140-6736(06)68508-5. PMID 16616561.
- Harris, Sam. "
- Mobbs, D. "Response to Greyson et al.: there is nothing paranormal about near-death experiences", Trends in Cognitive Sciences, Volume 16, Issue 9, September 2012, Page 446
- Near-death experiences are 'electrical surge in dying brain'Surge of neurophysiological coherence and connectivity in the dying brain
- Holden, Janice Miner; Greyson, Bruce; James, Debbie, eds. (Jun 22, 2009). "The Field of Near-Death Studies: Past, Present and Future". The Handbook of Near-Death Experiences: Thirty Years of Investigation. Greenwood Publishing Group. pp. 1–16. ISBN 978-0-313-35864-7.
- Ring, K. "Life at death. A scientific investigation of the near-death experience." 1980, New York: Coward McCann and Geoghenan.
- Greyson, Bruce (1983) "The Near-Death Experience Scale: Construction, reliability, and validity". Journal of Nervous and Mental Disease, 171, 369-375
- Greyson B. (1997)"The near-death experience as a focus of clinical attention". Journal of Nervous and Mental Disease. May;185(5):327-34. PubMed abstract PMID 9171810
- Morse M, Castillo P, Venecia D, Milstein J, Tyler DC. (1986) "Childhood near-death experiences". American Journal of Diseases of Children, Nov;140(11):1110-4.
- Mayank and Mukesh, 2004; Jansen, 1995; Thomas, 2004; Fenwick and Fenwick 2008
- Bassham, Gregory (2004). Critical Thinking: A Student's Introduction. McGraw-Hill, p. 485. ISBN 0-07-287959-9
- Near death experiences (NDEs): The dying brain:.
- NDE REdux:.
- Leaving Body And Life Behind:.
- Jane Dreaper, Study into near-death experiences, BBC News, 18 September 2008. Accessed 2008-09-20.
- Anthony Carroll, Hospital to study near-death experiences, EDP24, 19 September 2008. Accessed 2008-09-20.
- Anomalistics Psychology Research Unit - Invited Speaker Series 2009-10 Abstracts and biographies
- AWARE - Update from Dr. Parnia
- Fiona Macrae , Near-death experiences 'explained': Scientists believe it's the last gasp of a dying brain, Daily Mail, 31 May 2010. Accessed 2012-08-15.
- Gallup, G., and Proctor, W. (1982). Adventures in immortality: a look beyond the threshold of death. New York, McGraw Hill, pp. 198-200. "Have you, yourself, ever been on the verge of death or had a "close call" which involved any unusual experience at that time?". Nationally 15% responded "yes".
- Knoblauch, H., Schmied, I. and Schnettler, B. (2001). "Different kinds of Near-Death Experience: a report on a survey of near-death experiences in Germany",Journal of Near-Death Studies, 20, 15-29.
- Perera, M., Padmasekara, G. and Belanti, J. (2005), "Prevalence of Near Death Experiences in Australia". Journal of Near-Death Studies, 24(2), 109-116.
- Martens PR (1994) "Near-death-experiences in out-of-hospital cardiac arrest survivors. Meaningful phenomena or just fantasy of death?" Resuscitation. Mar; 27(2):171-5. PubMed abstract PMID 8029538
- Parnia S, Waller DG, Yeates R, Fenwick P (2001) "A qualitative and quantitative study of the incidence, features and aetiology of near death experiences in cardiac arrest survivors". Resuscitation. Feb; 48(2):149-56. PubMed abstract PMID 11426476
- J.C. Saavedra-Aguilar and Juan S. Gómez-Jeria. "A Neurobiological Model for Near-Death Experiences". Journal of Near-Death Studies, 7(4) Summer 1989. Pp. 205-222. http://188.8.131.52:8080/jspui/handle/2250/14775
- Rick Strassman (with Slawek Wojtowicz, Luis Eduardo Luna and Ede Frecska), "Inner Paths to Outer Space: Journeys to Alien Worlds through Psychedelics and Other Spiritual Technologies", 376 pages, Park Street Press, 2008, ISBN 978-1-59477-224-5
- Rick Strassman, DMT: The Spirit Molecule: A Doctor's Revolutionary Research into the Biology of Near-Death and Mystical Experiences, 320 pages, Park Street Press, 2001, ISBN 0-89281-927-8
- Rick Strassman, Hallucinogens (chapter), in Mind-Altering Drugs: The Science Of Subjective Experience, 402 pages, Oxford University Press, 2005, ISBN 0-19-516531-4
- Bruce Greyson, Kevin Nelson, Susan Blackmore, webpage:News-wdeath11-2006-04.
- Engmann, Birk: Near-death Experiences: A review on the thesis of pathoclisis, neurotransmitter abnormalities, and psychological aspects. MMW-Fortschr.Med.Nr.51-52/2008(150.Jg.)p.42-43. PMID 19156957
- Vogt C, Vogt O: Erkrankungen der Großhirnrinde im Lichte der Topistik, Pathoklise und Pathoarchitektonik. Journal für Psychologie und Neurologie; Bd. 28. Joh.- Ambr.- Barth- Verlag. Leipzig. 1922 (German)
- , Carbon Dioxide May Explain 'Near Death Experiences, Science Daily, 08 April 2010. Accessed 2011-08-25.
- James Owen , Near-Death Experiences Explained?, National Geographic, 08 April 2010. Accessed 2011-08-25.
- French, C. "Near-death experiences in cardiac arrest survivors", Chapter 25 of S. Laureys (Ed.), Progress in Brain Research, Vol. 150, ISSN 0079-6123
- Arzy S, Seeck M, Ortigue S, Spinelli L & Blanke O. Induction of an illusory shadow person. Nature 2006; 443:287.
- Hopkin, Michael (20 September 2006), "Brain Electrodes Conjure up Ghostly Visions", Nature, doi:10.1038/news060918-4
- L. Renemane, Z. Straume, B. Kupca, "Psychiatric phenomena among cardiologic patients who have survived a clinical death", European Neuropsychopharmacology, Volume 22, Supplement 2, October 2012, Pages S218-S219, ISSN 0924-977X, 10.1016/S0924-977X(12)70321-8.
- Young, Saundra (2009-10-16). "Doctor says near-death experiences are in the mind". CNN. Retrieved 2014-05-27.
- Lynne Levitan; Stephen LaBerge (1991). "Other Worlds: Out-of-Body Experiences and Lucid Dreams". Nightlight (The Lucidity Institute) 3 (2-3).
- Green, J. Timothy (1995). "Lucid dreams as one method of replicating components of the near-death experience in a laboratory setting". Journal-of-Near-Death-Studies 14: 49. "A large phenomenological overlap among lucid dreams, out-of-body experiences, and near-death experiences suggests the possibility of developing a methodology of replicating components of the near-death experience using newly developed methods of inducing lucid dreams. Reports on the literature of both spontaneous and induced near-death-experience-like episodes during lucid dreams suggest a possible protocol."
- Thaler, S. L. (1993) 4-2-4 Encoder Death, WCNN'93, Portland: World Congress on Neural Networks, July 11–15 ..., Volume 1, available at http://books.google.com/books?id=yVc5MmYWv1sC&pg=SA11-PA144&lpg=SA11-PA144&dq=4-2-4+encoder+death+thaler&source=bl&ots=UUMcwVxznJ&sig=ZmRMxn3WZZw_w6ZioxRl13SfsTs&hl=en&sa=X&ei=n6HAUfmKHoywrgGh1YF4&ved=0CCoQ6AEwAA#v=onepage&q=4-2-4%20encoder%20death%20thaler&f=false
- Yam, P., "Daisy, Daisy" Do computers have near-death experience, Scientific American, May 1993.
- Strok, D., Dying by design, IEEE Expert, Dec.1993.
- Thaler, S. L. (1995). Death of a gedanken creature, Journal of Near-Death Studies, 13(3), Spring 1995.
- Thaler, S. L., The death dream and near-death darwinism, Journal of Near-Death Studies, 15(1), Fall 1996.
- Thaler, S. L. (1995) "Virtual Input Phenomena" Within the Death of a Simple Pattern Associator, Neural Networks, 8(1), 55–65.
- Orne RM. (1995) "The meaning of survival: the early aftermath of a near-death experience". Research in Nursing & Health. 1995 Jun; 18(3):239-47. PubMed abstract PMID 7754094
- Greyson B. (1997) "The near-death experience as a focus of clinical attention". Journal of Nervous and Mental Disease. May; 185(5):327-34. PubMed abstract PMID 9171810
- The diagnostic label of "Religious or spiritual problem" is included in DSM-IV under the category of "Other conditions that may be a focus of clinical attention". See American Psychiatric Association (1994) Diagnostic and Statistical Manual of Mental Disorders, fourth edition. Washington, D.C.: American Psychiatric Association (Code V62.89, Religious or Spiritual Problem).
- Shushan, Gregory (2009) Conceptions of the Afterlife in Early Civilizations: Universalism, Constructivism and Near-Death Experience. New York & London, Continuum. ISBN 978-0-8264-4073-0
- Cultural Differences
- "Do religion and culture affect a Near Death Experience ( NDE )?" Horizon Research Foundation
- Kelly EW. (2001) . Death Stud. Apr-May;25(3):229-49
- Rivas T. (2003). "The Survivalist Interpretation of Recent Studies into the Near-Death Experience." Journal of Religion and Psychical Research, 26, 1, 27-31.
- Mahendra Perera, Karuppiah Jagadheesan, Anthony Peake. 2011. Making Sense of Near-Death Experiences: A Handbook for Clinicians. pp 62-73
- Sabom, Michael. Light & Death: One Doctor's Fascinating Account of Near-Death Experiences. 1998. Grand Rapids, Michigan: Zondervan Publishing House
- Rodrigues, Linda Andrade. Ex-atheist describes near-death experience. Standard Times, Page C4, January 31, 2004. www.southcoasttoday.com
- Is There Such a Thing as Life After Death? TIME
- Greyson, B. (2003). Incidence and correlates of near-death experiences in a cardiac care unit. General Hospital Psychiatry, 25(4), 269-276.
- Ring, Cooper, 1999
- Atwater, PMH (2001). Coming Back to Life; The After-Effects of the Near-Death Experience (2001 Revised and Updated ed.). Kensington Pub Corp. pp. 111–112. ISBN 978-0-8065-2303-3.
- Atwater, PMH (2007). The Big Book of Near-Death Experiences; The Ultimate Guide to What Happens When We Die (2nd, illustrated ed.). Hampton Roads Publishing. pp. 59–60. ISBN 978-1-57174-547-7.
- Barnes, Linda L.; Sered, Susan Starr (2005). Religion and Healing in America (illustrated ed.). Oxford University Press. pp. 399–400. ISBN 978-0-19-516796-2.
- "Anita M's NDE" NDERF
- Kimberli Wilson
- 90 Minutes in Heaven by Don Piper
- Heaven is For Real by Todd Burpo
- "Parallel Universes, a Memoir from the Edges of Space and Time" by Linda A. Morabito
- "Best Sellers". Combined Print & E-Book Nonfiction. The New York Times. April 25, 2012. Retrieved November 21, 2012.
- Mavrothalassitis, Apostolos (2012). The Friend From Mexico: A True Story of Surviving an Intensive Care Unit. Translated by David J. Horn. ASIN B00A7VSCJ8. ISBN 978-1-48103-491-3.
|Wikimedia Commons has media related to Near-death experiences.|
- International Association for Near-Death Studies (IANDS)
- "Peace of Mind: Near-Death Experiences Now Found to Have Scientific Explanations". Scientific American.
- "Why a Near-Death Experience Isn’t Proof of Heaven". Scientific American.
- "Near-Death Experiences". Susan Blackmore.
- "Hallucinatory Near-Death Experiences". Internet Infidels.
- "Near-Death Experience" (NDE). Skeptic's Dictionary.
- "Darkness, Tunnels, and Light". Skeptical Inquirer.