We show that accounts of NDEs, including the experiences of blind people, and NDE research methods used by popular researchers in the USA lack scientific credibility, at least with regard to their explanations of the possible origin of the extraordinary experiences. In order to be scientifically valuable, NDE research has to follow verification and validation of the data. While the verification of the content of NDE reports – the personal truth of the NDE themes – has been established, validation via objective scientific methods is largely missing.

Modern experimental techniques in exploring and understanding our brain and mind have shown that brain processes are intimately connected with the generation of states of consciousness. Against this background, near-death experiences (NDEs), including out-of-body experiences (OBEs), can be validated as phenomena generated in altered states of consciousness of the mind. In the history of research on NDE phenomena, paranormal or metaphysical explanations often included personal views and belief in a “life after life” or purely speculative quantum physical approaches to consciousness. The assurance that extraordinary experiences such as NDEs have their origin in physiology-dependent psychological processes of the brain of the experiencer, and not in an unknown, paranormal, or mystical entity, points to therapies usable by medical and psychological professionals to help all those who may suffer from confusion, disorientation, or fear as aftereffects of their experiences.

NDE-like phenomena have been reported in human societies all over the world. NDE narratives are often embedded in people’s cultural and religious backgrounds. In Europe, the earliest NDE reports were published in the eighteenth century. With the publication of Moody’s book (1975), NDEs became part of a popular esoteric culture in the USA. Even professionals in the medical field such as physicians, psychiatrists, and psychologists adopted Moody’s view about NDEs as evidence of a temporary separation of non-material consciousness/mind/soul from the material body/brain. This belief in paranormal explanations of NDEs then spread to other Western countries.

Near-death experiences, including out-of-body experiences, are introduced as personally perceived phenomena which are now open to informed scientific explanations. Recent progress in monitoring brain activity in altered states of consciousness and during the process of dying provide the bases for the explanations. Consciousness is introduced as a key factor for the understanding of NDEs. Also discussed are the history, phenomenology, incidences, scientific models, and examples of personal near-death experiences. These aspects will be combined in the book to show how personal truth against the background of belief and credo can change to the understanding of NDEs as a window on the amazing complexity of our brain and mind.

Reports about NDEs of children, from teenagers down to fetuses in the mother’s womb, have shown content and themes of the experiences very similar if not identical to the NDE themes of adults. The science-based explanation for this consistency of NDE themes, across virtually all ages, considers the known development of the nervous system, of memory functions, of language acquisition, and of social communication in childhood. Since episodic memory – the content of NDEs – can be recalled only for short periods (days, weeks) in children of 2 years and younger with no or little language competence, the narratives of their NDEs may not reflect their genuine experiences. Instead, their NDE knowledge can be assumed to be learned from communicative interactions with adults. Esoteric approaches to childrens’ NDEs, often published together with fanciful NDE stories in popular books, represent belief or credo while lacking scientific credibility.

Paranormal explanations of NDEs generally refer to the dualistic view of the world. These explanations are built upon the belief or derived from the credo that NDEs can be explained through paranormal concepts.

Near-death experiences often happen in a situation of high physiological and/or psychological stress. Sustained cardiac arrest, which is the important criterion for clinical death, is a situation in which the oxygenation level of the brain drops drastically. Without resuscitation and depending on physical and physiological conditions, the lack of oxygen causes a cascade of changes in neural activity of the brain continuing over about 10 minutes until neurons become irreversibly damaged and die. Levels of brain damage with prospective chances of recovery to normal are classified in scales of awareness and wakefulness. Neural activity measured as brain waves in EEG recordings after cardiac arrest shows phases of well-organized patterns comparable with EEG patterns during aware stimulus perception and/or action planning. Clinically dead patients, who are observed as unconscious, may subjectively perceive visual/auditory images and may report on their perceptions of near-death experiences after successful resuscitation.

It is reasonable and scientifically appropriate to search for neural correlates of near-death experiences (including out-of-body experiences, OBEs) in the context of altered states of consciousness (ASCs). Our survey of the literature showed direct connections from NDEs via ASCs to brain mechanisms. Dualistic and paranormal approaches, subjective belief, and approaches via quantum physics appear either scientifically inadequate or premature to provide explanations for the NDE/OBE phenomena.

Historically, clinical death was taken as “death” and people wondered about how a dead person with a dead brain could experience something. The assumption emerged that the mind, spirit, or consciousness can survive in the period of death independently of material support: that is, independently of the brain. Modern methods of measuring brain activity have shown that coordinated neuronal activity in networks of the brain can survive clinical death for a while and may produce extraordinary experiences such as NDEs. Themes of NDEs (NDE content) can be reproduced in a variety of experimental models, all leading to altered states of consciousness of the affected persons. The personal truth of NDE stories, verified in the analysis of numerous NDE reports, and the experimental validation of NDE themes in several models under well-controlled conditions, lead to the scientifically adequate conclusion that NDE phenomena are brain-based expressions of neuronal activity in conditions of altered states of consciousness.

Results from studies on brain activity in situations of hypoxia, application of anesthetics and other psychoactive drugs, epileptic seizures, electrical stimulation of brain areas, lucid dreams, and dream-like hallucinations of several geneses have shown that the reports of people who had perceptions and experiences related to these situations showed strong accordance with NDE reports. NDE themes can be reproduced experimentally, often in a predictable way. Such contexts and situations can be used as scientifically appropriate models for NDE release. Knowledge about and control of brain activation during the occurrence of NDE-like phenomena can be essential for understanding their generation.

Near-death experiences often have pervasive and long-lasting aftereffects in the lives of the affected persons. These aftereffects may concern personal attitudes to their own death, beliefs and spiritual life, social relationships, and other important aspects of life such as health care and work. Despite hundreds of collected and analyzed NDE reports, in the publications of many NDE researchers there is no discussion of such aftereffects that take a scientific perspective on NDE phenomena. From a scientific point of view, we can attest stagnation in the field of most NDE research. This stagnation will continue as long as researchers remain in the mental tradition of Moody, misinterpreting or ignoring studies on brain activity in metabolic stress, on brain physiology in the progression to brain death, and on the relationship between levels of consciousness and signatures in electroencephalograms.

By grounding the stories of near-death experiences (NDEs) in modern scientific evidence, the authors aim to demystify them and place them within the broader context of human cognition and perception. This book is an invitation to understand the near-death experience not as an enigmatic anomaly but as a natural part of the human condition, informed by our biology and the remarkable capacities of the brain. It is our hope that readers will gain not only a deeper appreciation for the scientific explanations behind NDEs but also a greater respect for the resilience and complexity of the human mind.

Experimental research about reliability, emotional expression, and possible fantasy and illusion in memories of NDEs is a new field of study. NDEs are stored as episodic memory and constitute an important part of the self-defining memory. NDE memories appear as real as memories of real events, and may contain even more detail and vividness than memories of real events. NED memories also seem to include illusions that may help a person to interpret their extraordinary experience. EEG data suggest that NDE memories reproduce illusions that were encoded as if they were real events. Studies on the encoding, storage, and retrieval of memories built in altered states of consciousness, such as states of dreaming or generation of hallucinations, can be used to model the encoding, storage, and retrieval of NDE memories.