Semiology and Mechanisms of Near-Death Experiences

Chinese translation and validation of the Near-Death Experience Content scale

Introduction

In recent years, a growing number of near-death experience (NDE) testimonies have been collected worldwide due to an increasing interest in research on this phenomenon. China has many patients who survive life-threatening situations, leaving over much data on NDEs to be collected for research. In the historical context of Eastern civilization, many mentally controlled practices in China can also lead to "NDEs-like" (e.g., meditation). This study aimed (1) to translate and validate the recently developed Near-Death Experience Content (NDE-C) scale into Chinese and (2) to quantify and identify NDEs and NDEs-like in China with this new Chinese version of the NDE-C scale.

Methods

Here, we presented the work that had been performed to translate the NDE-C scale into Chinese and validated this version on 79 NDE testimonies.

Results

Brislin's back-translation model was performed to translate a Chinese version of the NDE-C scale and internal consistency (the Cronbach's α value for the total group = 0.846) as well as the confirmatory factor analysis was conducted.

Discussion

Currently, the Chinese version of the NDE-C scale is ready for use in research practice in the context of Eastern culture, to screen people who have experienced an NDEs(-like) and to quantify their subjective experience, promoting further NDEs-related research in China.

Near-death experiences are associated with rapid eye movement (REM) sleep intrusions in migraine patients, independent of migraine aura

BACKGROUND AND PURPOSE

Migraine aura, near-death experiences (NDEs), and rapid eye movement (REM) sleep intrusions might share common mechanisms. Here, we investigated the prevalence of NDEs and REM sleep intrusions in people with migraine. We hypothesized that NDEs and REM sleep intrusions are more prevalent in migraine patients with aura than in those without.

METHODS

We conducted a prospective cross-sectional cohort study at a tertiary headache center, based on a prespecified sample size (n = 808). Migraine patients completed a series of questionnaires, including questions about demographic and headache characteristics, the 16-item Greyson NDE scale, four questions about REM sleep intrusions, and the Depression, Anxiety, and Stress Scale 21 (DASS-21).

RESULTS

Of 808 migraine patients (mean age 44.4 ± 13.3 years, 87.0% women), 353 (43.7%) had a current or previous history of migraine aura. Prevalence of NDE was 2.7% and not different in patients with and without aura (2.8% vs. 2.6%; p > 0.999). REM sleep intrusions were reported by 5.4% of participants and in a similar proportion of patients with and without aura (6.3% vs. 4.9%; p = 0.43). However, participants with REM sleep intrusions had had an NDE more often than participants without REM sleep intrusions (n = 5/44, 11.4% vs. n = 17/754, 2.2%; p = 0.005). Higher DASS-21 scores were associated with REM sleep intrusions (p < 0.001).

CONCLUSIONS

In this tertiary center cohort study, the prevalence of NDE and REM sleep intrusions was not influenced by migraine aura status. However, we identified an association between NDE and REM sleep intrusions, which corroborates the notion that they might share pathophysiological mechanisms.

Effects of Knowledge of Near-Death Experiences (NDEs) on Life Changes in People without NDEs

Background and Objective: Near-death experiences (NDEs) greatly change the lives of Near-death experiencers (NDErs); however, the influence of the knowledge of these experiences on other people is unclear. Therefore, the present study aimed to investigate the effects of knowledge of NDEs on various aspects of life and the sleep quality of those without NDEs. Methods: The research population consisted of people aged 12-60 years living in a number of different cities in Iran during 2021. A total of 766 out of 800 individuals who met the inclusion criteria completed the self-report questionnaires. Also, 466 respondents (60.8%) were women. Results: The findings of the study indicated that 57.6%, 58.1%, 72.1%, 79.6%, and 70.9% of the respondents acquired knowledge about NDEs through reading books and articles, watching movies and clips, using social media and networks, listening to lectures, and chatting with friends, respectively. Data analysis showed that 40% of the respondents reported a drastic change in their views or feelings and 57% experienced positive effects in their lives after learning about NDEs. Overall, the data in this study confirmed that most individuals were profoundly affected after exposure to NDEs. Conclusion: Knowledge of NDEs improves the quality of life, mental health, sleep quality, and the understanding of the life and death of most individuals without NDEs. Although there are some changes that are not necessarily positive and in some cases changes have been associated with negative consequences, later in this paper, the relevant associations and cautions are discussed.

Between life and death: the brain twilight zones

Clinically, and legally, death is considered a well-defined state of the organism characterized, at least, by a complete and irreversible cessation of brain activities and functions. According to this pragmatic approach, the moment of death is implicitly represented by a discrete event from which all cerebral processes abruptly cease. However, a growing body of experimental and clinical evidence has demonstrated that cardiorespiratory failure, the leading cause of death, causes complex time-dependent changes in neuronal activity that can lead to death but also be reversed with successful resuscitation. This review synthesizes our current knowledge of the succeeding alterations in brain activities that accompany the dying and resuscitation processes. The anoxia-dependent brain defects that usher in a process of potential death successively include: (1) a set of changes in electroencephalographic (EEG) and neuronal activities, (2) a cessation of brain spontaneous electrical activity (isoelectric state), (3) a loss of consciousness whose timing in relation to EEG changes remains unclear, (4) an increase in brain resistivity, caused by neuronal swelling, concomitant with the occurrence of an EEG deviation reflecting the neuronal anoxic insult (the so-called "wave of death," or "terminal spreading depolarization"), followed by, (5) a terminal isoelectric brain state leading to death. However, a timely restoration of brain oxygen supply-or cerebral blood flow-can initiate a mirrored sequence of events: a repolarization of neurons followed by a re-emergence of neuronal, synaptic, and EEG activities from the electrocerebral silence. Accordingly, a recent study has revealed a new death-related brain wave: the "wave of resuscitation," which is a marker of the collective recovery of electrical properties of neurons at the beginning of the brain's reoxygenation phase. The slow process of dying still represents a terra incognita, during which neurons and neural networks evolve in uncertain states that remain to be fully understood. As current event-based models of death have become neurophysiologically inadequate, I propose a new mixed (event-process) model of death and resuscitation. It is based on a detailed description of the different phases that succeed each other in a dying brain, which are generally described separately and without mechanistic linkage, in order to integrate them into a continuum of declining brain activity. The model incorporates cerebral twilight zones (with still unknown neuronal and synaptic processes) punctuated by two characteristic cortical waves providing real-time biomarkers of death- and resuscitation.

Incidence of near-death experiences in patients surviving a prolonged critical illness and their long-term impact: a prospective observational study

BACKGROUND

So far, the few prospective studies on near-death experience (NDE) were carried out only in intensive care unit (ICU) patients with homogeneous aetiologies, such as cardiac arrest or trauma survivors. The aims of this 1-year prospective and monocentric study were to investigate the incidence of NDE in ICU survivors (all aetiologies) as well as factors that may affect its frequency, and to assess quality of life up to 1 year after enrolment.

METHODS

We enrolled adults with a prolonged ICU stay (> 7 days). During the first 7 days after discharge, all eligible patients were assessed in a face-to-face interview for NDE using the Greyson NDE scale, dissociative experiences using the Dissociative Experience Scale, and spirituality beliefs using the WHOQOL-SRPB. Medical parameters were prospectively collected. At 1-year after inclusion, patients were contacted by phone to measure quality of life using the EuroQol five-dimensional questionnaire.

RESULTS

Out of the 126 included patients, 19 patients (15%) reported having experienced a NDE as identified by the Greyson NDE scale (i.e. cut-off score ≥ 7/32). In univariate analyses, mechanical ventilation, sedation, analgesia, reason for admission, primary organ dysfunction, dissociative and spiritual propensities were associated with the emergence of NDE. In multivariate logistic regression analysis, only the dissociative and spiritual propensity strongly predicted the emergence of NDE. One year later (n = 61), the NDE was not significantly associated with quality of life.

CONCLUSIONS

The recall of NDE is not so rare in the ICU. In our cohort, cognitive and spiritual factors outweighed medical parameters as predictors of the emergence of NDE. Trial registration This trial was registered in Clinicaltrials.gov in February 2020 ( NCT04279171 ).

Women's Experiences of a Close Brush With Death and Posttraumatic Growth

OBJECTIVE

To describe the experiences of women who have had a close brush with death and the elements of posttraumatic growth as a result of their experiences.

DESIGN

Using a theoretical framework of posttraumatic growth, we conducted a qualitative descriptive study with interviews of women who have had a close brush with death.

SETTING

Women were interviewed in the environment of their choosing: in their home, at a coffee shop, or over the telephone.

PARTICIPANTS

Twelve women ages 35 to 79 years from the United States participated in the study, all of whom reported having a close brush with death.

METHOD

Interviews were conducted using a semistructured interview guide derived from the theoretical framework.

RESULTS

Five themes emerged from the data: My Trauma Experience, My Will to Live, SupportWas Important, Putting the Pieces of My Life Back Together, and Near-Death Experiences. Participants reported having experienced various elements of posttraumatic growth. Many attributed their posttraumatic growth to a myriad of factors such as having a supportive network, their belief in God as a source of strength, and the will to live. Others credited health care professionals for quality care and encouragement.

CONCLUSION

Knowledge development regarding posttraumatic growth can enhance nursing practice in the care of women as they navigate life after trauma. Nurses and other health care providers are in strategic positions to educate women about the possibility of posttraumatic growth after adversity. They can help women find their path with a strong voice after trauma. Women who have experienced posttraumatic growth can teach others about healing, coping, empathy, compassion, and the importance of human connection.

Neuro-functional modeling of near-death experiences in contexts of altered states of consciousness

Near-death experiences (NDEs) including out-of-body experiences (OBEs) have been fascinating phenomena of perception both for affected persons and for communities in science and medicine. Modern progress in the recording of changing brain functions during the time between clinical death and brain death opened the perspective to address and understand the generation of NDEs in brain states of altered consciousness. Changes of consciousness can experimentally be induced in well-controlled clinical or laboratory settings. Reports of the persons having experienced the changes can inform about the similarity of the experiences with those from original NDEs. Thus, we collected neuro-functional models of NDEs including OBEs with experimental backgrounds of drug consumption, epilepsy, brain stimulation, and ischemic stress, and included so far largely unappreciated data from fighter pilot tests under gravitational stress generating cephalic nervous system ischemia. Since we found a large overlap of NDE themes or topics from original NDE reports with those from neuro-functional NDE models, we can state that, collectively, the models offer scientifically appropriate causal explanations for the occurrence of NDEs. The generation of OBEs, one of the NDE themes, can be localized in the temporo-parietal junction (TPJ) of the brain, a multimodal association area. The evaluated literature suggests that NDEs may emerge as hallucination-like phenomena from a brain in altered states of consciousness (ASCs).

Losing the Self in Near-Death Experiences: The Experience of Ego-Dissolution

Many people who have had a near-death experience (NDE) describe, as part of it, a disturbed sense of having a “distinct self”. However, no empirical studies have been conducted to explore the frequency or intensity of these effects. We surveyed 100 NDE experiencers (Near-Death-Experience Content [NDE-C] scale total score ≥27/80). Eighty participants had their NDEs in life-threatening situations and 20 had theirs not related to life-threatening situations. Participants completed the Ego-Dissolution Inventory (EDI) and the Ego-Inflation Inventory (EII) to assess the experience of ego dissolution and inflation potentially experienced during their NDE, respectively. They also completed the Nature-Relatedness Scale (NR-6) which measures the trait-like construct of one’s self-identification with nature. Based on prior hypotheses, ratings of specific NDE-C items pertaining to out-of-body experiences and a sense of unity were used for correlational analyses. We found higher EDI total scores compared with EII total scores in our sample. Total scores of the NDE-C scale were positively correlated with EDI total scores and, although less strongly, the EII and NR-6 scores. EDI total scores were also positively correlated with the intensity of OBE and a sense of unity. This study suggests that the experience of dissolved ego-boundaries is a common feature of NDEs.

The evolutionary origin of near-death experiences: a systematic investigation

Near-death experiences are known from all parts of the world, various times and numerous cultural backgrounds. This universality suggests that near-death experiences may have a biological origin and purpose. Adhering to a preregistered protocol, we investigate the hypothesis that thanatosis, aka death-feigning, a last-resort defense mechanism in animals, is the evolutionary origin of near-death experiences. We first show that thanatosis is a highly preserved survival strategy occurring at all major nodes in a cladogram ranging from insects to humans. We then show that humans under attack by animal, human and ‘modern’ predators can experience both thanatosis and near-death experiences, and we further show that the phenomenology and the effects of the two overlap. In summary, we build a line of evidence suggesting that thanatosis is the evolutionary foundation of near-death experiences and that their shared biological purpose is the benefit of survival. We propose that the acquisition of language enabled humans to transform these events from relatively stereotyped death-feigning under predatory attacks into the rich perceptions that form near-death experiences and extend to non-predatory situations.

Hystero-epilepsy in the Tuesday Lessons and NMDA receptor function: A hypothesis for dissociative disorder

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis patients demonstrate characteristic multistage progression and movement disorders, which are analogous to hystero-epilepsy in Jean-Martin Charcot's Tuesday Lessons. First, based on a review of the Tuesday Lessons recorded by Charcot's pupils, we hypothesized that there were patients with anti-NMDAR encephalitis among those diagnosed with hystero-epilepsy in the nineteenth century. We found acute-onset multiple neuropsychiatric manifestations resembling anti-NMDAR encephalitis among patients with hystero-epilepsy. Patients with drug withdrawal syndrome, dissociative and conversion disorders and patients under hypnosis from the modern point of view were also identified. These results suggested that hystero-epilepsy in the Tuesday Lessons could encompass dissociative and conversion disorders, hypnosis, drug withdrawal syndrome, and anti-NMDAR encephalitis-like manifestations. Based on Charcot's observations and current progress in molecular biology, such as the identification of glutamate/NMDAR system dysfunction in drug withdrawal syndrome, we then hypothesized that patients with dissociative and conversion disorders and those under hypnosis could also have hypofunction of the glutamatergic system. The NMDAR hypofunction hypothesis is emerging as a pathogenesis of schizophrenia. NMDAR antagonists are known to evoke symptoms similar to schizophrenia, anti-NMDAR encephalitis and near-death experiences. In current clinical reports, spectrum disorders such as dissociative disorder and conversion disorder have been observed in patients with anti-NMDAR encephalitis. Our hypothesis will offer an expansion of the NMDAR hypofunction hypothesis from psychosis to functional neurological disorders and normal specific situations, such as hypnosis, thanatosis, and near-death experiences.

Near-Death Experience among Iranian Muslim Cardiopulmonary Resuscitation Survivors

BACKGROUND

Near-Death Experience (NDE) refers to a broad range of subjective experiences associated with forthcoming death. The majority of Cardiopulmonary Resuscitation (CPR) survivors experience NDEs. It seems that near-death events are experienced differently by people with different cultural and religious viewpoints. Thus, this study aimed to explain NDEs in Iranian Muslim CPR survivors.

MATERIALS AND METHODS

A qualitative hermeneutic phenomenological approach influenced by Ricoeur was used to understand the meaning of CPR survivors' NDEs. Eight survivors were interviewed in private. The study was conducted in southeast Iran. In-depth, semi-structured interviews were used for data collection, and probing questions were added when necessary. The duration of the interviews was between 40 and 65 min. According to Lindseth and Norberg, in the naive understanding phase, we read the interviews several times for achieving naive understanding. In the structural analysis phase, the whole text is divided into meaningful units. Finally, the researchers formulated a comprehensive understanding of the contextualization of the text.

RESULTS

Four main themes emerged including 1) pleasing experiences along with flying and seeing light, 2) the experience of transport to the beyond, 3) out-of-body experience, and 4) reviewing life and memories in a religious context.

CONCLUSIONS

Iranian Muslim CPR survivors, reported NDEs, much similar to those reported by survivors in Western countries with different theistic religions. This means that medical professionals dealing with these patients need to be aware of such experiences in Iranian Muslims.

The Neurology of Death and the Dying Brain: A Pictorial Essay

As neurologists earn their living with the preservation and restoration of brain function, they are also well-positioned to address the science behind the transition from life to death. This essay in pictures highlights areas of neurological expertise needed for brain death determination; shows pitfalls to avoid during the clinical examination and interpretation of confirmatory laboratory tests in brain death protocols; illustrates the great variability of brain death legislations around the world; discusses arguments for the implementation of donation after circulatory death (DCD); points to unresolved questions related to DCD and the time between cardiac standstill and organ procurement (“hands-off period”); provides an overview of the epidemiology and semiology of near-death experiences, including their importance for religion, literature, and the visual arts; suggests biological mechanisms for near-death experiences such as dysfunction of temporoparietal cortex, N-methyl-D-aspartate receptor antagonism, migraine aura, and rapid eye movement sleep; hypothesizes that thanatosis (aka. death-feigning, a common behavioral trait in the animal kingdom) represents the evolutionary origin of near-death experiences; and speculates about the future implications of recent attempts of brain resuscitation in an animal model. The aim is to provide the reader with a thorough understanding that the boundaries within the neurology of death and the dying brain are being pushed just like everywhere else in the clinical neurosciences.

Near-Death Experience as a Probe to Explore (Disconnected) Consciousness

Forty-five years ago, the first evidence of near-death experience (NDE) during comatose state was provided, setting the stage for a new paradigm for studying the neural basis of consciousness in unresponsive states. At present, the state of consciousness associated with NDEs remains an open question. In the common view, consciousness is said to disappear in a coma with the brain shutting down, but this is an oversimplification. We argue that a novel framework distinguishing awareness, wakefulness, and connectedness is needed to comprehend the phenomenon. Classical NDEs correspond to internal awareness experienced in unresponsive conditions, thereby corresponding to an episode of disconnected consciousness. Our proposal suggests new directions for NDE research, and more broadly, consciousness science.

Migraine aura, a predictor of near-death experiences in a crowdsourced study

Background

Near-death experiences (NDE) occur with imminent death and in situations of stress and danger but are poorly understood. Evidence suggests that NDE are associated with rapid eye movement (REM) sleep intrusion, a feature of narcolepsy. Previous studies further found REM abnormalities and an increased frequency of dream-enacting behavior in migraine patients, as well as an association between migraine with aura and narcolepsy. We therefore investigated if NDE are more common in people with migraine aura.

Methods

We recruited 1,037 laypeople from 35 countries and five continents, without any filters except for English language and age ≥18 years, via a crowdsourcing platform. Reports were validated using the Greyson NDE Scale.

Results

Eighty-one of 1,037 participants had NDE (7.8%; CI [6.3-9.7%]). There were no significant associations between NDE and age (p > 0.6, t-test independent samples) or gender (p > 0.9, Chi-square test). The only significant association was between NDE and migraine aura: 48 (6.1%) of 783 subjects without migraine aura and 33 (13.0%) of 254 subjects with migraine aura had NDE (p < 0.001, odds ratio (OR) = 2.29). In multiple logistic regression analysis, migraine aura remained significant after adjustment for age (p < 0.001, OR = 2.31), gender (p < 0.001, OR = 2.33), or both (p < 0.001, OR = 2.33).

Conclusions

In our sample, migraine aura was a predictor of NDE. This indirectly supports the association between NDE and REM intrusion and might have implications for the understanding of NDE, because a variant of spreading depolarization (SD), terminal SD, occurs in humans at the end of life, while a short-lasting variant of SD is considered the pathophysiological correlate of migraine aura.

Prevalence of near-death experiences in people with and without REM sleep intrusion

Background

The origin and prevalence of near-death experiences are unknown. A recent study suggested a link with REM sleep intrusion but was criticized for its selection of control participants. We therefore assessed the association of REM intrusion and near-death experiences with different methods.

Methods

Using a crowd-sourcing platform, we recruited 1,034 lay people from 35 countries to investigate the prevalence of near-death experiences and self-reported REM sleep intrusion. Reports were validated using the Greyson Near-Death Experiences Scale (GNDES) with ≥7 points as cut-off for near-death experiences.

Results

Near-death experiences were reported by 106 of 1,034 participants (10%; 95% CI [8.5–12%]). Evidence of REM intrusion was more common in people with near-death experiences (n = 50∕106; 47%) than in people with experiences with 6 points or less on the GNDES (n = 47∕183; 26%) or in those without such experiences (n = 107∕744; 14%; p =  < 0.0001). Following multivariate regression analysis to adjust for age, gender, place of residence, employment and perceived danger, this association remained highly significant; people with REM intrusion were more likely to exhibit near-death experiences than those without (OR 2.85; 95% CI [1.68–4.88]; p = 0.0001).

Discussion

Using a crowd-sourcing approach, we found a prevalence of near-death experiences of 10%. While age, gender, place of residence, employment status and perceived threat do not seem to influence the prevalence of near-death experiences, we confirmed a possible association with REM sleep intrusion.