Biological Aspects of Near-Death Experiences

BIOLOGICAL ASPECTS OF NEAR-DEATH EXPERIENCES BRUCE GREYSON* Near-death experiences (NDEs) are profound psychological events with transcendental or mystical elements typically occurring to individuals close to death or in situations of intense physical or emotional danger. Such experiences, once regarded as meaningless hallucinations, have become the subject of serious study by medical and other researchers in recent years. Near-death experiences are important to physicians not only because they may occur to patients while under our care, but because they often lead to profound aftereffects that may affect health and response to medical treatments, and because they may help us understand the interaction between mind and body, particularly as that interface is affected by the dying process. Once thought to be rare, the NDE is estimated to occur to a third of people who come close to death, or about 5 percent of the American population [1-3]. Although the term "near-death experience" and its acronym were not coined until 1975, accounts of similar events can be found in the folklore and writings of European, Middle Eastern, African, Indian, East Asian, Pacific, and Native American cultures. The phenomenon was first described as a clinical syndrome in 1892, when Heim published a collection of cases of mountain climbers who had fallen in the Alps (as he himself had done) , soldiers wounded in war, workers who had fallen from scaffolds, and individuals who had nearly died in accidents and near-drownings; this article was translated into English 80 years later [4, 5] . The term "near-death experience" was coined by Moody to denote "any conscious perceptual experience which takes place during ... an event in which a person could very easily die or be killed (and may even be so close as to be believed or pronounced clinically dead) but nonetheless survives, and continues physical life" [6] . More recently, Moody has redefined neardeath experiences as "profound spiritual events that happen, uninvited, to *Box 152, Health Sciences Center, University ofVirginia, Charlottesville, VA 22908; email: cbg4d@virginia.edu.© 1998 by The University of Chicago. All rights reserved. 0031-5982/98/4201-1079$01.00 14 Bruce Greyson ¦ Biological Aspects of Near-Death Experiences some individuals at the point ofdeath' ' [7] . TheDictionary ofModern Medicine has offered a more specific definition ofthe near-death experience: A phenomenon of unclear nature that may occur in patients who have been clinically dead and then resuscitated; the patients report a continuity ofsubjective experience , remembering visitors and other hospital events despite virtually complete suppression of cortical activity; near-death experiences are considered curiosities with no valid explanation in the context of an acceptable biomedical paradigm; the trivial synonym, Lazarus complex, refers to the biblical Lazarus who was raised from the dead by Jesus of Nazareth [8]. Predisposing Factors Near-death experiences are reported by individuals who had been pronounced clinically dead but then resuscitated, by individuals who actually died but were able to describe their experiences in their final moments ("deathbed visions"), and by individuals who, in the course of accidents or illnesses, feared that they were near death. Researchers have identified very few personal traits or variables that can predict who will have an NDE, or what kind of NDE a person may have. Retrospective studies of near-death experiencers have shown them collectively to be psychologically healthy individuals, who do not differ from control groups in age, gender, race, religion, religiosity, or mental health [2, 912 ]. Locke and Shontz found NDErs to be indistinguishable from control subjects in intelligence, neuroticism, extroversion, trait and state anxiety, and relevant Rorschach measures [13]. However, some studies have suggested that NDErs tend to be good hypnotic subjects, remember their dreams more often, and are adept at using mental imagery, and tend to acknowledge significant childhood trauma and resultant dissociative tendencies [11, 14, 15]. It is not clear, however, whether these personal traits and recall of prior experiences are the results of having had an NDE, or whether people who already have those characteristics are more prone to have NDEs when they come close to death. Children's NDEs are similar to those of adults, except that they tend not to include a life review or meetings with deceased friends and relatives...