I wrote about this topic in my book Borderlands (1997), and since the relevant passage pretty much exactly addresses your question, I am excerpting it here. The passage appears as part of a much longer section of the book arguing that cultural factors have significantly impacted on the ways in which unusual events are experienced and reported.

Given the time that has passed since I wrote, there will no doubt be more to say, but hopefully this will serve as an introduction to the topic, at least:

The “near death experience” is one of the most widely encountered of supposedly paranormal phenomena, and has been reported from many very different societies over considerable periods of times. Nevertheless, the evidence shows that the NDE, too, is subject to significant historical and cultural influences – not what we would expect if it was a purely medical phenomenon.

One of the most obvious differences between twentieth-century accounts and their precursors of the mediaeval era is the journey undertaken by the dying soul. Modern near death experiences generally involve a journey down a lengthy tunnel towards a pinprick of bright, white light which, if reached, seems to reveal itself as a sort of ante-room to heaven. This was not the case in the earlier period. Surviving accounts of mediaeval NDEs frequently include vivid descriptions of two alternative afterlifes – one in heaven, and the other in purgatory or hell.

There are other fundamental differences between mediaeval and modern experiences: earlier accounts lay great emphasis on judgement and the tests and torments a soul must undergo before entering heaven. This accords to contemporary religious belief. Similarly, modern cases tend to involve an educational and non-judgmental ‘life review’ which the dead are encouraged to conduct themselves, a view of the afterlife perfectly in keeping with the self-obsession of the late twentieth century. Carol Zaleski, who has made a particular study of the history of the near death experience, suggests that the mediaeval NDE reflects the period’s universal faith in the reality of post-mortem reward and punishment, while its modern equivalent has been shaped both by a sharp decline in belief in the existence of hell (something that has not stopped most people from at least hoping for a heaven) and new imagery of the afterlife developed and popularised by spiritualism. Zaleski concludes with the suggestion that the near death experience is ‘a work of the narrative imagination, shaped not only by the universal laws of symbolic experience, but also by the local and transitory statutes of a given culture.’

Support for this contention comes from a study of the NDE in mediaeval China and Japan, most of which do contain the core features of guides, god-like beings, a structured afterlife and the dramatic reform of the witness’s previous lifestyle upon recovery. There are, for example, differences between Taoist near death experiences, which focus on heaven, and Buddhist NDEs, which are much more concerned with hell. Indeed it would appear that the experiences of a number of monks who returned from the dead with accounts of many-tiered hells ruled over by different gods played a significant role in shaping Buddhist concepts of what happens after death. Moreover, once a strong image of the afterlife was well established in Chinese Buddhist scripture, subsequent NDEs became substantially less concerned with the topography of hell: a number of ‘visitors’ who wished to witness souls in torment were informed that tours were no longer allowed. In consequence, Chinese NDEs came to more closely resemble modern accounts of the near death experience during the late mediaeval and early modern periods.

All of this suggests that physiology alone cannot explain every aspect of the near death experience and that NDEs do have a cultural component which can substantially shape the experience itself.

It is also well worth pointing out that events which seem remarkably like near death experiences can occur when the brain is not in fact in the process of dying through progressive oxygen starvation. One western case concerned a typical NDE reported by a man who had plunged from a cliff and imagined he was certain to die on the rocks below. Another, from mediaeval Japan, is told of the monk Honen, who is reputed to have introduced the Pure Land school of Buddhism to the country late in the twelfth century. As a gesture of devotion, Honen took to chanting the name of Amida, the king of the Pure Land – heaven – up to 70,000 times a day (about 100 times a minute). This enormously repetitive task seems to have helped to induce altered states of consciousness in which the monk experienced many visions, which he carefully recorded between the years 1198 and 1212. Among them are a number of apparent NDEs.

Another interesting variation concerns experiences which occur while the witness is in a coma, rather than undergoing a near-death experience. These suggest that the NDE need not be as limited in duration and scope as is implied by recent western cases, which generally involve the rapid resuscitation of the witness at or before the moment in which he encounters the ‘being of light’. There may even be a correlation between the degree of detail in the experience and the length of time that the witness was unconscious. Among a number of ancient Chinese records of apparent near death experiences is the case of Chao T’ai, a native of Hupeh province who spent 10 days in a coma. His NDE was particularly complex, and involved being met by two horsemen who took him along a road east to a large city. After passing through the gates, Chao was taken before an entity dressed in scarlet and told to list his sins. The entity then informed Chao that he had been chosen to make an inspection of the heavenly city’s water-works, which among other things serviced an underground inferno. Chao’s lengthy tour of inspection gave him the opportunity to witness the various punishments inflicted on souls consigned to the various levels of hell, and also the efficacy of various Buddhist rituals performed by the living for the dead. Eventually it was discovered that Chao had been called to the city prematurely owing to a bureaucratic error (a characteristically Chinese detail which it is hard to imagine could have been repeated in, say, an NDE account from Dark Age Europe) and he was instructed to return to the waking world and inform those still living about the afterlife.

Sources

Carol Zaleski, Otherworld Journeys: Accounts of Near-Death Experience in Medieval and Modern Times (Oxford: Oxford University Press 1987); James McClenon, Wondrous Events: Foundations of Religious Belief (Philadelphia: University of Pennsylvania Press 1994); Ian Stevenson, ‘Survival after death: evidence and issues’, in Ivor Grattan-Guinness (ed), Psychical Research: A Guide to its History, Principles & Practices in Celebration of 100 Years of the Society for Psychical Research (Wellingborough: Aquarian Books 1982).