A near-death experience (NDE) is a deep and meaningful experience that happens when someone is very close to dying or has died temporarily. Researchers say these experiences often share similar features. Most, but not all, NDEs are described as positive. People may feel separated from their bodies, experience floating, feel calm and safe, sense warmth, feel happiness, see a bright light, or meet deceased family members. They might also feel as though their body is dissolving or recall important events from their lives. While some parts of NDEs are common, how people explain these experiences often depends on their culture, beliefs, or religion.

NDEs usually happen during times when a person’s heartbeat or breathing stops but can be restarted. Scientists and religious groups offer different explanations for NDEs. Some studies in neuroscience suggest that NDEs may result from how the body processes senses during dangerous situations. Other beliefs, such as those about life after death, include descriptions that are similar to NDEs.

Etymology

The French term "expérience de mort imminente" (meaning "experience of imminent death") was first suggested by French psychologist Victor Egger in the 1890s. This came from talks between philosophers and psychologists about climbers' stories of seeing their lives flash before their eyes during falls. In 1892, Albert Heim reported personal accounts from workers who fell from scaffolds, injured soldiers, climbers who fell from high places, and others who nearly died, like in near-drowning incidents or accidents. This was the first time this phenomenon was called a medical condition.

In 1968, Celia Green studied 400 first-hand reports of out-of-body experiences. This was the first effort to create a classification system for these experiences, which were seen as unusual experiences of seeing or sensing things or hallucinations. In 1969, psychiatrist Elisabeth Kübler-Ross, an expert in near-death experiences, published her famous book On Death and Dying: What the Dying Have to Teach Doctors, Nurses, Clergy, and Their Own Families.

John C. Lilly used the term "near-death experience" in 1972. In 1975, psychiatrist Raymond Moody made this term widely known. He used it as a general term for experiences like out-of-body experiences (OBEs), the "panoramic life review," seeing a bright light, passing through a tunnel, or reaching a border.

Characteristics

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The original text discusses Raymond Moody's 1975 study on NDEs, the 15 elements he identified, the four post-experience elements, Kenneth Ring's five-stage model, and the 2022 guidelines that differentiate authentic NDEs from mislabeled ones. It also mentions the cultural influences on NDE interpretations, negative NDEs, and Bruce Greyson's questionnaire.

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Check for any technical terms that might be too advanced and find simpler equivalents. For instance, "corroboration of the experience" could be "others confirming the experience." Make sure that the flow is logical, moving from Moody's study, through Ring's model, to the guidelines, and then to the cultural and negative NDE aspects.

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In 1975, psychiatrist Raymond Moody studied about 150 patients who all said they had experienced a near-death experience (NDE). He found that these experiences often had 15 common elements. Moody studied 50 of these cases closely. A key similarity among all the patients was that they had been very sick, faced life-threatening situations, or had died. Of the 15 elements, 11 describe the experience itself:

• Feeling it is hard to explain the experience in words.
• Learning from others that they were dead.
• Feeling pain replaced by comfort or peace.
• Hearing strange sounds or music.
• Moving through a dark tunnel.
• Feeling separated from their body.
• Seeing other people.
• Meeting a bright being.
• Reviewing their life in detail.
• Reaching a point where they could not return.
• Returning to their body and life.

Moody also noted four elements that happened after the experience:
1. Talking about the experience with others.
2. Changes in how they lived their life.
3. Seeing death differently.
4. Others confirming the experience was real.

Moody explained that not all NDEs include every element, and each experience might be different.

Kenneth Ring (1980) simplified Moody’s findings into five stages:
1. Feeling calm.
2. Feeling separated from the body.
3. Entering darkness.
4. Seeing a bright light.
5. Entering a new world through the light.

The final stage is returning to life after being resuscitated.

Over time, studies on NDEs have included patients with different medical and non-medical conditions, making it harder to compare results. Recent guidelines suggest clearly separating patients who had authentic NDEs (as Moody described) from other experiences. These guidelines emphasize focusing on patients whose experiences match Moody’s original description:
1. A connection to death.
2. Feeling beyond the physical world.
3. Difficulty describing the experience.
4. Positive changes in life tied to a deeper sense of meaning.

The guidelines also recommend focusing on patients who:
– Lost consciousness due to serious illness.
– Did not have typical coma symptoms like dreams or confusion, even if they were in the ICU or elsewhere.

These points help distinguish real death-related experiences from other conditions.

Because the term "near-death" is not clearly defined, many studies now include patients who were not close to death, such as those under anesthesia. Some researchers argue that authentic NDEs (from people facing death) and mislabeled NDEs (from people not facing death) are very different. Authentic NDEs often involve clarity, meaning, and a review of life, while experiences from drugs like ketamine or DMT include strange imagery and self-centered thoughts.

Another researcher noted that some common traits exist across NDEs, such as:
– 50% feeling they were dead.
– 56% feeling peaceful or happy.
– 24% having an out-of-body experience (seeing their body from outside).
– 31% entering darkness or a tunnel.
– 32% seeing deceased loved ones or religious figures.

Cultural beliefs often shape how people interpret NDEs. For example, in the U.S., the "light" is often seen as angels or loved ones, while in Hinduism, it is seen as a messenger of death.

After Moody’s work, reports of unpleasant NDEs (called "hellish" NDEs) began to appear. These experiences are different from classic NDEs and are often linked to medical conditions like delirium or hallucinations, not true NDEs.

People who survive suicide attempts may describe intense emotional pain they see as self-created torment.

To better understand NDEs, Bruce Greyson created a questionnaire with 80 characteristics to study common effects and sensations.

Establishment of research framework

In 2022, guidelines were created to improve how researchers study people’s experiences when they come close to death. Instead of using the term "near-death experience" (NDE), the guidelines now use "recalled experience of death" (RED) because it is more accurate. A RED is a real near-death experience, as described in the 2022 Guidelines under "Common Elements." It is a specific mental and emotional event that happens during a time when a person loses consciousness due to a serious, life-threatening situation, such as a heart stopping. REDs share the same key features as real near-death experiences described by Moody:

• A close connection with death.
• A feeling of moving beyond the physical world.
• A sense that the experience is too complex to describe clearly.
• Positive changes in a person’s life that lead to a greater understanding of meaning and purpose.

REDs do not include signs of typical coma-related events, such as dreams, confusion, or false beliefs. The term RED is clearer than "near-death" because it includes both situations where a person is very close to death (from a medical perspective) and situations where the body is actually going through the process of dying, such as when the heart stops. The authors of the 2022 guidelines believe using RED will help researchers study these experiences more effectively. Studying REDs will help avoid mixing different types of experiences, such as hallucinations caused by drugs, dreams, or memories formed during recovery from a coma.

Historical reports

Near-death experiences (NDEs) have been written about for many years. The earliest known medical report about NDEs was written by Pierre-Jean du Monchaux, an 18th-century French doctor. He described one such experience in his book Anecdotes de Médecine. Du Monchaux believed that an increase in blood flow to the brain caused a strong feeling in the person, leading to an NDE. In the 19th century, some studies looked at more than just single cases. One was conducted privately by members of the Church of Jesus Christ of Latter-day Saints, and another took place in Switzerland. By 2005, 95% of cultures around the world had mentioned NDEs in some way.

In the United States, about nine million people have reported having an NDE, according to a 2011 study in Annals of the New York Academy of Sciences. Most of these experiences happened because of serious injuries to the body or brain. More recent reports show that:
• 17% of critically ill patients experienced an NDE in nine studies from four countries.
• 10–20% of people who came close to death had an NDE.

Near-death studies

Bruce Greyson (a psychiatrist), Kenneth Ring (a psychologist), and Michael Sabom (a cardiologist) helped start the study of near-death experiences and introduced it to schools and research institutions. From 1975 to 2005, about 2,500 people in the United States who reported near-death experiences were studied in research that looked back at their experiences. An additional 600 people in the Western world outside the U.S. and 70 people in Asia were also studied in this way. Prospective studies, which follow groups of people (such as patients in emergency rooms) and check if they had a near-death experience during the study, identified 270 individuals. These studies are more expensive to conduct. In total, about 3,500 people were studied between 1975 and 2005. These studies were carried out by about 55 researchers or teams of researchers.

Melvin L. Morse, who leads the Institute for the Scientific Study of Consciousness, and his colleagues studied near-death experiences in children. Researchers from the University of Michigan, led by Jimo Borjigin, found that parts of the brain involved in seeing things were more active during cardiac arrest. After a specific type of brain activity occurred in the posterior TPO areas, other brain regions connected to the front of the brain showed increased activity as the heart rate slowed. These connections were especially strong in people whose brain activity crossed the middle of the brain. Studies suggest that these brain connections are important for remembering things and learning.

American radiation oncologist Jeffrey Long collected information about near-death experiences through the Near Death Experience Research Foundation (NDERF). Out of 1,122 people who had near-death experiences, 835 reported feeling more alert and conscious, even though studies found no electrical activity in their brains. His second piece of evidence shows that people who had near-death experiences could describe their resuscitation process with 97.6% accuracy. Long also found seven other pieces of evidence that support the idea that near-death experiences are real, even though some cannot be proven with current medical tools. He concluded that even though near-death experiences are not fully explained by science, they are likely real.

According to research, the study of near-death experiences involves discoveries, challenges, and debates. Scientists have noted that interest in near-death experiences has grown as medical technology and resuscitation methods have improved. This topic is widely discussed in search results, medical papers, and opinions. Some researchers believe the field includes both scientific and non-scientific views. Many scientists and doctors have been skeptical about near-death studies, and early research was often not taken seriously. However, more scientists now accept near-death experiences as a legitimate subject for study, though this change has been slow.

Research shows that psychiatrists have helped recognize and popularize near-death experiences and the research around them. Scholars have noted that interest in the topic has grown as more people talk about it. While there is no agreement on the meaning of near-death experiences, many researchers believe studying them is now a valid scientific field. Some hope recent discoveries may lead to a better understanding of what happens when people are near death.

Kovoor and others found that some studies on near-death experiences have method problems. They said that long-term results might be influenced by health conditions rather than the near-death experience itself. Skeptics say it is hard to confirm many of the stories used to describe near-death experiences. Some scientists and researchers have criticized the field, including those who study near-death experiences. In an open letter, Kenneth Ring pointed out that religious beliefs might influence near-death studies. He said that the field has attracted many religious and spiritual groups, which may affect how research is conducted and discussed.

A 2021 study of 101 patients who had a medical procedure called deep hypothermic circulatory arrest found that none of them had a near-death experience.

Clinical research in cardiac arrest patients

In 2001, Sam Parnia and other researchers shared the findings of a one-year study at Southampton General Hospital. The study included 63 people who had survived cardiac arrest. These individuals had been officially dead, with no heartbeat, no breathing, and unchanging, wide-open eyes. Parnia and his team tested claims about out-of-body experiences by placing objects on high shelves facing the ceiling, where patients could not see them from the floor. Four people reported near-death experiences (NDEs), but none described seeing the objects. Psychologist Chris French noted that none of the participants in this study experienced an out-of-body experience.

In 2001, Pim van Lommel, a doctor from the Netherlands, and his team studied 344 patients who had survived cardiac arrest in 10 Dutch hospitals. Patients who did not report NDEs were compared with those who did. Researchers examined differences in psychological factors (such as fear before the event), demographics (like age and gender), medical details (such as the number of CPR attempts), and medication use between the two groups.

The study also followed up with both groups (those who had NDEs and those who had not) at two and eight years later to track life changes. One patient described an out-of-body experience, during which he watched and remembered events during his cardiac arrest. Hospital staff confirmed his account. This experience was not likely a hallucination, as the details matched real, verifiable events.

At the University of Southampton, Parnia led the AWARE Study, which began in 2008 and ended in 2012. This research involved 33 scientists across 15 medical centers in the UK, Austria, and the US. The study tested whether patients had awareness, memories, or consciousness during cardiac arrest. Researchers used tests to check the accuracy of claims about seeing or hearing things. One test involved placing shelves with images on the ceiling in rooms where cardiac arrests were likely to occur, so hospital staff could not see them. The study’s results were published in October 2014.

A review of the study’s findings showed that out of 2,060 cardiac arrest events, 101 of 140 survivors completed questionnaires. Of these 101 patients, 9% had near-death experiences. Two patients (2% of those who completed the questionnaires) described seeing or hearing real events during their cardiac arrest. These events did not occur in rooms with ceiling shelves, so their claims could not be tested objectively. One patient was too ill for her account to be verified. The second patient’s experience was confirmed, showing awareness occurred minutes after the heart stopped, a time when the brain typically stops functioning and has no electrical activity. This experience did not match a hallucination or imaginary event because visual and auditory details could be confirmed.

As of May 2016, a plan for AWARE II was listed on the UK Clinical Trials Gateway website. This two-year study aimed to observe 900–1,500 cardiac arrest patients. Recruitment began on August 1, 2014, and the study was originally scheduled to end on May 31, 2017. It was later extended until 2020. In 2019, a summary of the study with 465 patients was shared. Only one patient remembered hearing sounds, while no one remembered seeing images. In November 2022, the full study results were published.

Explanatory models

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In a 2005 review article, psychologist Chris French grouped models that try to explain near-death experiences (NDEs) into three main categories. These categories are not completely separate from each other, but they have a lot in common: spiritual (or transcendental), psychological, and physiological.

French summarizes this by saying: "the most popular interpretation is that the NDE is exactly what it appears to be to the person having the experience." The NDE would show that the mind or soul can exist outside the body after death and that it can have knowledge about a world beyond the physical one.

According to Greyson, some NDE events are difficult to explain with what we currently know about the body and mind. For example, when patients were unconscious, they could accurately describe events from a position outside their bodies. In two studies of patients who had survived a cardiac arrest, those who said they left their bodies could correctly describe what happened during their resuscitation or other unexpected events, while others described incorrect equipment and procedures. Sam Parnia also refers to two cardiac arrest studies and one deep hypothermic circulatory arrest study where patients reported seeing and hearing things even when their brain activity had stopped. These reports matched real events that had happened.

Five studies were done to test if people who have NDEs can accurately describe things they see from outside their bodies. These studies placed unusual objects in places where people having NDEs might see them, such as in the upper corners of rooms in emergency departments, coronary care units, or intensive care units. Twelve patients said they left their bodies, but none could describe the hidden objects. Even though this is a small number of people, the fact that they could not describe the hidden objects makes people question the accuracy of the stories about NDEs.

Neuroscientist Charlotte Martial says there is not enough strong scientific evidence to support the idea of non-local consciousness, which some people claim exists. Chris French has said that the survivalist idea, which suggests the soul continues to exist after death, does not create clear and testable ideas. Because of the lack of clear details, the survivalist idea can explain any results and is not scientific.

French summarizes the main psychological explanations, which include the depersonalization, the expectancy, and the dissociation models.

The depersonalization model was proposed in the 1970s by psychiatrist Russell Noyes and clinical psychologist Roy Kletti. They said that NDEs are a type of depersonalization, which can happen when people are in very emotional situations, like facing death. According to this model, people who are close to death may feel separated from their bodies and surroundings, lose their feelings, and experience time in a strange way.

This model has some problems in explaining NDEs for people who do not feel like they are outside their bodies. Unlike NDEs, these experiences are more like dreams and are unpleasant, with feelings of fear and emptiness. Also, during NDEs, people are very clear about who they are, and their sense of self does not change, unlike those who have depersonalization.

Another psychological theory is the expectancy model. It suggests that even though these experiences feel real, they are created in the mind, either on purpose or without thinking, as a response to the stress of facing death. These experiences are similar to wish-fulfillment, where people imagine a happy place because they are scared of dying. People use their own beliefs and culture to imagine a safe place that helps them deal with the fear of death.

People's stories often do not match what they expected about death, which challenges the idea that they imagined a scene based on their culture or beliefs. Although the term NDE was first used in 1975, the descriptions of NDEs have not changed much since then. The only difference is that more people describe seeing a tunnel. This means that the fact that more people know about NDEs after 1975 did not change the way people describe them. Another problem with this model is that children who have NDEs describe similar experiences to adults, even though children are not as influenced by religious or cultural ideas about death.

The dissociation model suggests that NDEs are a way for people to protect themselves from very stressful situations. In extreme situations, some people may avoid feeling certain emotions to prevent the pain of those feelings. They may also feel separated from their surroundings.

The birth model suggests that NDEs might be a way for the brain to relive the experience of being born. Just like a baby moves from darkness to light and is greeted by love and warmth, the brain of a dying person might imagine moving through a tunnel to light and warmth. People who are born through a cesarean section or naturally report seeing a tunnel equally often. However, newborns do not have the ability to see clearly, understand space, or remember things, so they cannot remember their birth.

Many different physical explanations for NDEs have been suggested, including brain conditions like lack of oxygen, too much carbon dioxide, and the release of certain brain chemicals. Scientists and doctors have studied these ideas. One researcher who focuses on the brain's role in NDEs is British psychologist Susan Blackmore, who proposed the "dying brain hypothesis."

According to Greyson, several brain-based models have been proposed, suggesting that NDEs may come from different parts of the brain, such as the limbic system, the hippocampus, the left and right temporal lobes, Reissner's fiber in the spinal cord, the prefrontal cortex, and the right temporal lobe. Neuroscientists Olaf Blanke and Sebastian Dieguez from the Ecole Polytechnique Fédérale de Lausanne in Switzerland suggest a brain-based model with two types of NDEs:

• "Type 1 NDEs are caused by damage to the front and back parts of the brain, especially on the right side, affecting the right temporal-parietal junction. These NDEs are characterized by out-of-body experiences, a changed sense of time, and feelings of flying or lightness."
• "Type 2 NDEs are also caused by damage to the front and back parts of the brain, especially on the left side, affecting the left temporal-parietal junction. These NDEs are characterized by feeling the presence of someone, meeting and talking to spirits, seeing glowing bodies, and hearing sounds and music without the feeling of moving."

They suggest that damage to the back part of the brain may…