Some scientists argue NDEs are constructed by the brain, not actually experienced

There's a new (contested) physiological explanation for near-death experiences based on analysis of the brains of resuscitated coma and cardiac arrest patients.

A leading expert on near-death experiences, psychiatrist Dr. Bruce Greyson, says that during his decades of research on this topic, this area of research has become far more mainstream and accepted as a rigorous area of inquiry.

The main criticism of a recent neurophysiological explanation for near-death experiences is that these events are too complex to be explained as a neurochemical response to an oxygen-deprived brain.

A radiation oncologist has studied near-death experience reports for over 25 years and compiled around 4,000 accounts in the hopes of finding more patterns that would reveal insights about consciousness and humans' final moments before or around death.

NDEs typically change people's outlooks drastically and can prompt depression

The phenomena are regularly categorized as hallucinations, but some specialists are interested in their psychological nuances. Many survivors report feeling less anxiety about death, though some surveys show the experiences can increase physiological sensitivities.

What happens in a dying brain?

Near-death experiences usually happen during death or on the border of life and death when a person isn't understood to be conscious. This article details the science of what's going on with the brain during NDEs.

A near-death experience is a phenomenon experienced by roughly 5% to 23% of the population, and typically occurs after a traumatic physical event or a brief clinical death.

The body's response to cardiac arrest has been linked to near-death experiences.

Brain activity sometimes goes into overdrive around the point of death according to researchers' recent analysis of patients' brains before and after they were taken off their ventilators.

Accounts of near-death experiences share similarities with hallucinogens, with reports of mystical-like states of consciousness across both contexts.

Meet the Dutch cardiologist who believes consciousness can exist outside the body

Dutch cardiologist Dr. Pim van Lommel conducted one of the largest studies of near-death experiences following cardiac arrest, publishing the results in the prestigous journel The Lancet. He later went on to argue (to significant criticism from peers) that his findings suggest consciousness can exist outside the body.

Psychiatrist Bruce Greyson created a scale to identify and rate NDEs

Researcher Bruce Greyson is one of the world’s leading experts on near-death experiences. This article explores what the field of NDE research has learned over the last five decades, discusses the difficulties of studying such a controversial topic, and outlines what we’ve ruled out as the cause of these events.

Near-death experiences can be reminiscent of religious visions, yet people across different faiths as well as those with no declared religion have reported them.

Near-death experiences have been reported across cultures for millennia.

Studies of psychedelic use may help shed light on the nature of consciousness

The nature of consciousness—what it is, where it comes from, and how it manifests as moment-to-moment experience—remains under debate by scientists. Recent studies show psychedelics were found to boost low-frequency brain signals known as delta waves, a behavior also seen during dream states.

A 'paranormal activity' unit at the University of Virginia studies challenges to mainstream scientific ideas about human consciousness.

Scientists are studying dying patients' brain activity in the final moments of life

In the final moments of life there are distinctive bursts of coordinated neural activity. Researchers are interested in parsing that data to better understand the dying process and also exploring how this data relates to our understanding of consciousness.

The dreaming brain, as understood by scientists

Technology has advanced to where the seemingly separate fields of psychology and neuroscience are asking the same questions about dreams, such as whether they're more closely related to perception or visualization. Some field-intersecting findings include research that shows people with impaired face perception don't dream of faces, those with brain legion-related cognition difficulties deal with similar issues in dreams, and children's dreams change in parallel to their cognitive development.

The oldest medical report of a near-death experience dates to around 1740.

Can physics explain where consciousness comes from?

Consciousness is a complex emergent phenomenon of the brain, which is primarily composed of neurons and glial cells. Since all matter is composed of atoms that follow the laws of physics, there may be quantum processes beyond classical electrochemical interactions that can explain where consciousness comes from.

Four in 10 CPR patients report consciousness not captured by standard measures.

The debate on why humans are conscious—and what that means

Understanding what consciousness is, and why and how it evolved, is perhaps the greatest mystery known to science. Watch interviews with the world's leading experts on what it is and whether we'll ever know.

How science explains déjà vu

Take a fun look at the science explaining the odd experience of déjà vu, which some theories suggest is actually a sign of a healthy brain.

Research advances suggest death takes much longer than we realized

Recent research indicates that organs, including the brain, are better at handling a lack of oxygen after the heart stops beating than previously known. Such findings may open up possibilities that include someday reversing certain death processes and expanding the availability of organs available for organ donations. (Some users may experience a paywall.)

Listen to an avowed rationalist discuss his frightening near-death experience visions from 2020 and how it changed his life outlook.

The neurobiology of meaningfulness: the benefits of psychedelics

Psychedelics produce powerful emotions in its users, including a profound sense of meaningfulness. The philosopher William James called this sense "noetic" in the late 19th century, but for decades researchers avoided studying the effects of such drugs on the brain. However, the recent resurgence in psychedelic research has heightened interest in the relationship between this noetic sense resulting from the therapeutic use of drugs. Learn what researchers have found out here.

Neural implants blur the line between personal intention and machine execution

A key ethical dilemma—the contemplation conundrum—explores whether implants might misinterpret mere imagination as intent to act. Neuroscientists have found no brain signal that clearly marks when someone decides to act, making intent hard to detect in neurotechnological systems.

Humans experience the world subjectively. What does that mean for scientific research?

When you close your eyes, do you see static or colorful patterns or an "intrinsic grey" known as Eigengrau in German? This variation of our internal experiences is just the tip of the iceberg, one that scientists are increasingly studying and...

Research suggests the brain maintains connections to lost limbs

Decades-old research suggested brain reorganization after amputations, but brain scans show unchanged limb representations. Phantom limb pain may result from such unchanged brain maps, which may enhance prosthetic limb control in brain-computer interface technology.

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

See the 16-question Greyson questionnaire on near-death experiences and how they're scored.

The University of Virginia has the nation's most established near-death studies division, but institutions including the University of Southampton, the University of Connecticut, and the University of North Texas have also explored the field.

Two scientists argue consciousness evolved through 'unlimited associative learning,' the ability to learn almost any new pattern during a lifetime.

Brain death is a uniquely modern problem stemming from modern ventilators.

Researchers use the brain's ability to edit memories to explore memory deletion

Scientists have successfully implanted false memories in mice after studying how the editing process works in the brain. Beyond potentially deleting memories in those with PTSD, upcoming research may allow clinicians to forecast the onset of neurodegenerative diseases.

Déjà vu is a memory illusion involving brain regions correcting inaccurate memories

Neuroscientists suggest the phenomenon is your brain recognizing that this feeling of familiarity is incorrect, showing off the brain's internal fact-checking system. Younger people experience déjà vu more often because their brains have higher excitatory activity and stronger memory monitoring systems.

Some founders of quantum mechanics thought consciousness could influence phenomena

Since quantum systems exist as a superposition of states before producing a definitive outcome, some quantum pioneers wondered if the act of conscious observation was what collapsed the wave function of possibilities into one state.

Dream interpretation has evolved from ancient mystical explanations, to dream reports, to tracking electrical activity in the brain and more.

Neural interfaces offer major medical potential but raise serious ethical concerns

Although brain-computer interfaces can help people recover lost functions and allow direct brain-to-computer communication in the future, surveys have shown little public support for using them to boost abilities like memory or focus in healthy people.

Watch this 2021 video demonstrating a full brain death examination

This video and accompanying article in the peer-reviewed New England Journal of Medicine show the then-standard steps of a full brain death examination—demonstrating the process on a medical dummy to search for pain, blinking, eye movement, cough, gagging, or other forms of responsiveness. (May need to sign up for a free account to view.)

Why the nature of consciousness is such a difficult problem

David Chalmers is one of the leading philosophers of consciousness. In this video, he outlines some of the major questions in this field, including the "hard problem of consciousness," which seeks to find neural correlate for every conscious experience.

How can octopuses and MDMA help scientists understand the human brain?

Research shows that psychedelics may induce something called "critical periods" in the adult brain, which can make our brains more open to learning and changing, like they once were back in early childhood. Psychedelics similarly change how social creatures like octopuses behave, which demonstrates that these animals could help us better understand our own neurobiology.

The study of dreams, formally called oneirology, has evolved over the centuries, from anecdotal interpretations to advanced brain imaging.

Sleep is no longer considered a binary state—scientists are seeking to map a variety of liminal states between sleep and waking, including the hypnagogic state associated with boosts of creativity.

Dreams largely occur during REM sleep (but not entirely).

Panpsychism suggests that all matter possesses consciousness

The theory describes consciousness as a fundamental, ubiquitous property, rather than separate or emerging from matter. Cosmopsychism posits that the universe is conscious, while some critics argue that consciousness itself may be an illusion.

Nonamputees can be tricked into thinking they have phantom limbs with rubber arm experiments.

In 1968, a Harvard Medical School committee issued the first neurological definition of death

The definition set a legal and medical precedent for how we define death, important for issues including organ donation. This 2020 video podcast discusses the history of brain death controversies and the variability in how death has been determined, including discussions in the late 1960s about when patients are considered dead in the context of organ donations.

Psychedelics set off a flurry of brain activity that may permanently alter it

The brain seems to experience a sharp increase in communication between areas that generally don't interact. New research suggests a thin, sheet-like gray matter structure tucked deep within the brain, between the insular cortex and striatum, may be the key to this change. The area is centrally located and home to many of the receptors that psychedelics target, potentially rewiring the brain and rewriting thought patterns.

Is life all about pleasure? Debating the Experience Machine

If you could plug into an Experience Machine that gave you total pleasure all the time, would you do it? Philosopher Robert Nozick thinks you wouldn't, using this as evidence against hedonism, the view that life is all about pleasure. Explore the nuances of the argument and counterarguments with this accessible article.