Critical Care
January 1, 2010
Bruce Greyson
15 citations
A commentary on a study linking hypercapnia and hypokalemia to near-death experiences (NDEs) urges caution. The original study found a correlation, but the commentary notes that hypercapnia may simply indicate better cardiac output and perfusion pressure, which reduces amnesia during cardiac arrest, making patients more likely to remember events and report NDEs. Contradictory evidence from other studies, including one finding lower carbon dioxide levels during NDEs and a prospective study of 63 cardiac arrest survivors finding no association, along with the small sample size and unclear link between blood and brain carbon dioxide levels, suggest the findings require further research.
The Journal of near-death studies
January 1, 2014
Bruce Greyson
14 citations
Spiritually transformative experiences are distinct from psychotic experiences in their context, content, how they are remembered, and their lasting effect on the individual. The article examines these differences without presenting new empirical data.
The Journal of near-death studies
January 1, 2006
Bruce Greyson, Janice Holden, J. Paul Mounsey
13 citations
During the surgical implantation of automatic implantable cardioverters/defibrillators (ICDs), cardiac arrest was induced under closely monitored conditions to test the device. A computer displayed unusual visual targets visible only from above eye level, looking down on the unconscious patient, to test the accuracy of out-of-body perceptions reported in near-death experiences. In a series of 52 induced cardiac arrests, no patient reported having had a near-death experience, and none reported a sense of leaving the physical body or observing from an out-of-body visual perspective. This failure to find a single NDE may have been due to preoperative reassurances.
Obstetrics and Gynecology
November 1, 2005
Alan T. Marty, Frank L. Hilton, Robert K. Spear et al.
12 citations
Survival after surgical removal of a massive blood clot from the lungs (embolectomy) following a cesarean delivery that causes sustained cardiac arrest is rare. In this case, a woman went into cardiac arrest and stopped breathing one day after an uncomplicated cesarean due to a pulmonary embolism. While continuous cardiopulmonary resuscitation was performed, doctors used a heart-lung machine connected to the leg vessels to allow successful removal of the clot. After waking, the patient reported a near-death experience. Pulmonary embolism causes about 2 deaths per 100,000 live births per year in the United States, and it is probably more common after cesarean than vaginal delivery. Massive pulmonary embolism after cesarean delivery can be treated even if continuous CPR is needed until embolectomy.
The Journal of near-death studies
January 1, 1981
Bruce Greyson
12 citations
Near-death experiences (NDEs) cannot be fully explained by reductionistic hypotheses. A case is made for psychological and psychodynamic interpretations of NDEs, arguing that these approaches should not be prematurely rejected. The paper restates the value of considering psychological frameworks alongside other explanations.
Psychology of Consciousness Theory Research and Practice
June 12, 2025
Etzel Cardeña, Aviva Berkovich‐ohana, Katja Valli et al.
11 citations
A multidisciplinary, international group used taxonomic principles and a modified Delphi method to create a taxonomy of altered states of consciousness based on central phenomenological features. They identified eight distinct states, some with subcategories: proto and transitional, delirium, minimal to no awareness, experiential detachment, enhanced physicality, altered identity, imaginary/fantasy/visionary, and unity/mystical. The authors hope this taxonomy will foster conceptual clarity and stimulate research across specializations, helping reveal what is common and different across triggers and antecedents of altered states, and encouraging phenomenological, psychological, cultural, and neuroscientific understanding.
The Journal of Nervous and Mental Disease
August 20, 2018
Surbhi Khanna, Lauren E. Moore, Bruce Greyson
11 citations
A 54-year-old man with bacterial meningitis experienced a complete recovery without neurological deficits despite a fluctuating Glasgow Coma Scale score between 6 and 11 during an 8-day hospitalization. He recalled an elaborate near-death experience that occurred while he was comatose. The case underscores the value of studying near-death experiences during compromised brain function to better understand consciousness.
Death Studies
February 23, 2005
Bruce Greyson
11 citations
Some people who say they have had a near-death experience (NDE) do not actually meet research criteria for one (false positives), while others who deny having had an NDE do meet those criteria (false negatives). The author assessed these false claims and denials in a group that promotes near-death research and among psychiatric outpatients. The rate of false positives and negatives differed depending on how common NDEs were in each sample and how much participants knew about them. Because participants' knowledge about NDEs can affect study results, using standardized criteria to identify NDEs is critically important.
The Journal of near-death studies
January 1, 2004
Bruce Greyson, Kenneth Ring
11 citations
The article presents the Life Changes Inventory-Revised, a standardized version of the scale that incorporates knowledge from previous drafts administered to diverse samples and from qualitative research on attitudinal changes reported by near-death experiencers.
Neuroscience and biobehavioral reviews
August 1, 2024
Marina Weiler, David J Acunzo, Philip J Cozzolino et al.
10 citations
Out-of-body experiences (OBEs), where individuals feel detached from their physical bodies, often lead to lasting increases in pro-social behaviors such as tolerance and empathy. This article proposes that these changes occur through ego dissolution—a sense of unity and interconnectedness similar to that induced by psychedelics. The authors examine potential brain mechanisms, focusing on the temporoparietal junction and the Default Mode Network, to explain how OBEs might enhance empathy. The work synthesizes existing ideas to illuminate the relationship between altered states of consciousness and empathic improvement.
The Journal of near-death studies
January 1, 2014
Masayuki Ohkado, Bruce Greyson
8 citations
Near-death experiences (NDEs) share some features across cultures but also show culture-specific elements. Japanese NDEs differ from Western ones in three main ways: the interpretation of and interaction with a light, the image of heaven, and the absence of a life review. These differences are explained by cultural factors rather than universal physiological or biological mechanisms.
The Journal of near-death studies
January 1, 2021
Bruce Greyson
7 citations
Near-death experiences (NDEs) can involve a variety of factors, and while psychedelic molecules may play a role in some cases, they are not relevant to all NDEs. The author responds to criticism of their book, clarifying that psychedelic substances are only one possible factor among many, and that the research on NDEs should not be reduced to a single explanation.
Journal of Scientific Exploration
December 28, 2023
Bruce Greyson
5 citations
Near-death experiences (NDEs) are usually profoundly positive, but distressing NDEs—involving fear, hellish imagery, or evil beings—occur in an estimated 11% to 22% of all NDEs. Their prevalence is hard to measure because experiencers often hide them due to shame or fear of judgment. Distressing NDEs take several distinct forms, and researchers attribute them to personal traits, biological factors during the crisis, or surrounding circumstances. Compared with pleasant NDEs, distressing NDEs produce fewer lasting aftereffects overall, possibly because experiencers avoid dwelling on them, though some do cause long-term emotional trauma. Experiencers use various strategies to cope and find meaning. More research is needed on causes, aftereffects, and links to other dark spiritual experiences.
The Journal of near-death studies
January 1, 2022
Bruce Greyson, Pim van Lommel, Peter Fenwick
4 citations
An invited commentary discusses how to interpret brainwave recordings from an elderly patient who suffered a cardiac arrest, and what those recordings might reveal about near-death experiences. The authors argue that certain patterns of electrical activity in the brain after cardiac arrest could correspond to the subjective phenomena reported by people who have had near-death experiences, though they caution that the relationship remains speculative and requires further investigation.
Psico-USF
April 1, 2010
Fernanda Barcellos Serralta, Fernanda Genro Cony, Zelia Cembranel et al.
4 citations
A Near-Death Experience Scale originally developed in English was translated into Brazilian Portuguese and tested for semantic equivalence. Two psychologists and two psychiatrists evaluated the translated version and confirmed that it matched the original in general and referential meaning. The scale was then pre-tested with six patients discharged from an intensive care unit at a university hospital, who demonstrated good comprehension of the items. The scale is therefore considered culturally appropriate for use in research on near-death experiences in Brazil.
Frontiers in Psychology
October 16, 2025
Bruce Greyson, Jeffrey D. Long, Janice Miner Holden et al.
3 citations
A new scale, the veridical Near-Death Experience Scale (vNDE Scale), was developed to assess how strong the evidence is for perceptions reported during near-death experiences. Thirteen experts used a Delphi method to agree on eight criteria, including timing of investigation, medical conditions, third-party verification, and the number and quality of perceptions, scored on a four-level Likert scale. The scale was then tested on 17 cases of potentially veridical NDEs by 11 human raters and three artificial raters using large language models. In 14 of the 17 cases (82.3%), human and artificial raters agreed at over 75% when considering two adjacent evidence levels, such as moderate plus strong or low plus very low. The scale offers a practical way to evaluate the evidential strength of reported NDE perceptions.
International review of psychiatry (Abingdon, England)
January 1, 2025
Bruno Angeli-Faez, Bruce Greyson, Pim van Lommel
3 citations
Near-death experiences (NDEs) during cardiac arrest likely occur when the patient is unresponsive and the brain is severely compromised, not in early arrest or after resuscitation. There is no evidence that cortical electrical activity recorded during dying or CPR is linked to NDEs; such recordings may be artifacts. Cardiac arrest halts blood flow to the brain, causing loss of cortical electrical activity within 10–30 seconds. During CPR, brain activity may remain absent or severely disturbed. Because NDEs appear at the moment the brain is severely compromised, this may support the idea that consciousness can persist beyond the brain.
Journal of Near-Death Studies
January 1, 2023
Bruce Greyson
3 citations
Consciousness in humans and animals is explored, with a focus on near-death experiences (NDEs) and how both species may psychologically and spiritually interact during moments close to death. The article suggests that animals, like humans, can have NDEs and that these experiences can create a shared, transcendent connection between them. This interaction is described as a mutual awareness or communication that occurs at the threshold of death, challenging purely materialist views of consciousness. The work argues for a broader understanding of consciousness that includes non-human animals and highlights the spiritual dimensions of dying.
University of North Texas Digital Library (University of North Texas)
January 1, 2007
Bruce Greyson
3 citations
Keith Augustine's critique of a transcendental interpretation of near-death experiences (NDEs) identifies weaknesses in research methodology, limited data, and gaps in arguments. He cites psychophysiological and cultural correlates favoring a hallucinatory view. However, his analysis relies on idiosyncratic definitions of psychological concepts, assumes unidirectional causality from bivariate correlations, and underestimates empirical predictions of the separation hypothesis. Although evidence for the transcendental hypothesis is not compelling, it accounts for NDE phenomenology better than the materialist model.
The Journal of near-death studies
January 1, 1991
Bruce Greyson
3 citations
Sixty-one consecutive suicide attempters were interviewed about near-death experiences. The article reports on the rate and characteristics of such experiences in a population expected to have high rates of both psychopathology and proximity to death.
Frontiers in Psychology
June 13, 2024
Marieta Pehlivanova, Marina Weiler, Bruce Greyson
2 citations
Belief in psychic phenomena is widespread but controversial. A leading hypothesis is that high belief is explained by differences in cognitive styles, but most research has been conducted with lay individuals. This study measured actively open-minded thinking (AOT) and need for closure (NFC) in four groups: academic psi researchers (N=44), lay psi believers (N=32), academic skeptics (N=35), and lay skeptics (N=33). Group differences appeared in AOT but not NFC. Academic psi researchers scored similarly to both skeptic groups on AOT (4.5 out of a possible range), while lay psi believers scored significantly lower (4.2), indicating less willingness to consider evidence that challenges their beliefs.
University of North Texas Digital Library (University of North Texas)
January 1, 2007
Bruce Greyson
2 citations
A critique of Keith Augustine's argument against veridical perception in near-death experiences shows that his claims rely on unsubstantiated speculation from popular media rather than on supportive data or peer-reviewed literature. Addressing the issues he raises could improve the methodology of near-death research and strengthen the evidential database for such perceptions.
Journal of Near-Death Studies
January 1, 2023
Bruce Greyson
1 citation
Near-death experiences (NDEs) have been studied for 50 years, yet no simple, widely accepted definition existed. This study surveyed 100 near-death researchers and 100 near-death experiencers to identify a brief, consensual description. Both groups agreed on the most common physical circumstances, features, and aftereffects of NDEs, leading to a proposed model conceptual description.
University of North Texas Digital Library (University of North Texas)
January 1, 2007
Bruce Greyson
1 citation
A letter to the editor responds to Augustine's article questioning whether paranormal perception occurs in near-death experiences. The author challenges the arguments presented in Augustine's work, offering a counterpoint to the skeptical view of paranormal elements in NDEs. The response engages with the philosophical and empirical debate surrounding the validity of paranormal perception during near-death states, suggesting that the evidence may support such phenomena more than Augustine allows.
The Journal of near-death studies
January 1, 2007
Bruce Greyson
1 citation
A response to Keith Augustine's critique argues that his objections to studies of veridical perception in near-death experiences rely on speculation from popular media rather than on data or peer-reviewed research. However, addressing the methodological issues he raises could improve near-death research and strengthen the evidence for veridical perception.