Near-death experiences: clinical implications

Background: When some people come close to death, they report a profound experience of transcending the physical world that often leads to spiritual transformation. These “near-death experiences” (NDEs) are relevant to clinicians because they lead to changes in beliefs, attitudes, and values; they may be mistaken for psychopathological states, although producing different sequelae requiring different therapeutic approaches; and because they may enhance our understanding of consciousness. Objectives: This literature review examined the evidences regarding explanations proposed to explain NDEs, including expectation, birth memories, altered blood gases, toxic or metabolic hallucinations, and neurochemical and neuroanatomical models. Methods: The literature on NDEs of the past 30 years was examined comprehensively, including medical, nursing, psychological, and sociological databases. Results: NDEs typically produce positive changes in attitudes, beliefs, and values, but may also lead to interpersonal and intrapsychic problems. These problems have been compared to various mental disorders, but are distinguishable from them. Various therapeutic strategies have been proposed to help experiencers with problematic aftereffects, but have not been tested yet. Conclusions: The mystical consciousness and higher mental activity during NDEs, when the brain is severely impaired, challenge current models of brain/mind interaction and may occasionally lead to more complete models for the understanding of consciousness. Greyson, B. / Rev. Psiq. Clín. 34, supl 1; 49-57, 2007 Key-words: Near-death experience, spiritual transformation, differential diagnosis, psychotherapy, consciousness. Correspondence address: Division of Perceptual Studies, University of Virginia Health System, P.O. Box 800152, Charlottesville, VA 22908-0152, USA. E-mail: [email protected] When some people come close to death, they go through a profound experience in which they believe they leave their bodies and enter some other realm or dimension, transcending the boundaries of the ego and the ordinary confines of time and space. Such experiences had been described sporadically in the medical literature since the 19th century (Greyson, 1998a) and had been identified as a discrete syndrome more than a century ago (Heim, 1892). Moody (1975) introduced the term neardeath experiences (NDEs) for these phenomena, and outlined 15 characteristic features commonly reported by American survivors. These 15 features, which have come to define near-death experiences both among the academic community and in the popular imagination, include ineffability, hearing the news of one’s death, overwhelming feelings of peace, hearing a noise, seeing a tunnel, a sensation of being out of the body, meeting nonphysical beings, a “Being of Light,” a life review, a border or point of no return, coming back to life, telling others about the experience, effects on lives, new views of death, and corroboration of knowledge not acquired through normal perception (Moody, 1975). Recent research suggests that near-death experiences are reported by 12% to 18% of cardiac arrest survivors (Greyson, 2003a; Parnia et al., 2001; van Lommel et al., 2001). Near-death experiences are important to physicians for three reasons. First, NDE precipitate pervasive and durable changes in beliefs, attitudes, and values. Second, they may be confused with psychopathological states, yet have profoundly different sequelae requiring different therapeutic approaches (Greyson, 1997a, 2003b). Third, clarification of their mechanisms may enhance our understanding of consciousness and its relation to brain function (Greyson, 1998b; Parnia and Fenwick, 2002). One of the problems with research into NDEs is that, with a few notable exceptions, almost all NDE research has been retrospective, raising the question of the reliability of the experiencer’s memories (French, 2001). Embellishment of near-death experience accounts, if it occurred, would diminish their importance and theoretical challenge. Autobiographical memories are subject to distortion over years, and memories of unusual or traumatic events may be particularly unreliable as a 50 Greyson,B. / Rev. Psiq. Clín. 34, supl 1; 49-57, 2007 result of emotional influences. To test the reliability of NDE accounts, Greyson (2006, in press) administered the NDE Scale, a quantitative measure of near-death experiences, to the same experiencers on two occasions about 20 years apart, in the early 1980s and then again in the 2000s. Contrary to claims that NDE accounts are embellished over time, there were no statistically significant differences between the NDE Scale scores on the two administrations, and changes in the NDE Scale score were not significantly associated with the elapsed time interval. This evidence that accounts of near-death experiences are reliable over a period of two decades supports the validity of studies of such experiences that had occurred years before their investigation.