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What Near-Death and Psychedelic Experiences Reveal about Human Consciousness

A colorful illustration meant to depict something psychedelic.

A recent Academy event explored near-death experiences and the medical application of psychedelic remedies, combining elements of science and philosophy.

By David Freeman

What is the nature of consciousness? What happens to it at the brink of death—and beyond? In what ways can the scientific study of near-death experiences and the medicinal use of psychedelic compounds boost our understanding of the human condition and our ability to ease emotional suffering?

These and related questions were the focus of an Academy conference held on June 8, 2023, in New York City. The one-day event included presentations by psychologists, neurologists, biomedical researchers and a religious scholar as well as a gripping first-person account of a near-death experience from renowned journalist and author Sebastian Junger.

What are Near-Death Experiences?

Near-death experiences, or NDE’s, are deeply affecting, often mystical episodes—experts call them periods of “disconnected consciousness”—that affect some people who are close to death or in situations of grave physical or emotional danger. They are commonly marked by feelings of floating outside one’s body and the sensation of moving toward a bright light, as well with as encounters with dead relatives.

NDE’s have been documented across many different cultures and have been known since ancient times. “We’re talking about something that could be hundreds of thousands of years old,” said Brian C. Muraresku, author of a 2020 book, “The Immortality Key,” that described scientific evidence for the ritual use of psychedelics in classical antiquity and one of the speakers at the conference.

There’s something about that kind of experience—near-death, psychedelic, mystical, whatever it is—that holds the entire human race together.

Brian C. Muraresku, author “The Immortality Key”

NDE’s are now known to be remarkably common. In recent research, 15 percent of intensive care unit patients and up to 23 percent of survivors of cardiac arrest reported having had one, according to neuropsychologist Helena Cassol, Ph.D., scientific coordinator of Neurological Rehabilitation Center of the University Hospital of Liege in Belgium and another conference speaker.

“More people have survived cardiac arrest and other situations and could recall those experiences” as a result of improved resuscitation techniques that have become available in recent years, she explained, adding that NDE’s now represent an emerging field of scientific research.

NDE’s can be personally transformative. Some people report a reduced fear of death in the wake of an NDE. Others report enhanced feelings of compassion or purpose. But some are saddled with a pattern of persistent intrusive thoughts or dreams or other negative after-effects. Given these possibilities, “I think it is important for people to be able to talk about these experiences and be heard in a nonjudgmental way,” Dr. Cassol said.

The Evolution of Near-Death Experiences

There may be an evolutionary basis for NDE’s. Conference speaker Daniel Kondziella, M.D., Ph.D., a neurologist at Copenhagen University Hospital and an associate professor at the University of Copenhagen in Denmark, described research linking the episodes to thanatosis. That’s the well-documented and remarkably consistent phenomenon in which animals—even insects—feign death in order to avoid being killed by predators.

The research suggests that the evolution of language in humans gave us the unique ability to transform this stereotyped behavior into the rich narratives used to describe the mysterious sensations and perceptions commonly seen in near-death experiences, Dr. Kondziella said. Not everyone is convinced by such research.

“Evolutionary explanations are just-so stories,” said Christof Koch, Ph.D., chief scientist and president of the Allen Institute for Brain Science, and another conference speaker. “They may be true. They made be false. It just doesn’t matter. But the fact that we do have experiences—that is the remarkable thing.”

Studies of the neurological underpinnings of NDE’s suggest that the phenomenon arises amid a sort of blending of conscious states: waking, rapid-eye movement (REM) sleep and non-REM sleep.

“The physiological balance between conscious states is disrupted during the conditions of near-death, leading the brainstem arousal system controlling conscious states to blend waking and rapid eye movement consciousness into a hybrid state” known as REM intrusion,” said Kevin R. Nelson, M.D., a University of Kentucky neurologist and another speaker at the conference. “REM intrusion leads to many key features of near-death, including lying still, visual activation, out-of-body, and the experience’s narrative qualities.”

Most individuals who experience near-death are physiologically predisposed to REM intrusion, according to Dr. Nelson.

Psychedelics as Medical Treatment

As some scientists work to gain a better understanding of NDE’s, others are pursuing clinical trials of psychedelic compounds, which have been shown to trigger an altered state of awareness similar to that seen in people experiencing an NDE. A growing body of evidence suggests that these compounds—given under expert supervision and in carefully controlled settings—can ease emotional distress in terminally ill people quite profoundly.

One landmark 2016 study by researchers including Anthony P. Bossis, Ph.D., clinical assistant professor of psychiatry at NYU Grossman School of Medicine and another speaker at the conference, showed that a single treatment with psilocybin—a psychoactive compound found in some mushroom species that humans have consumed for thousands of years—brought rapid reductions in depression, anxiety, and hopelessness in people with terminal cancer.

The benefits of psilocybin treatment were greatest among individuals who reported strong mystical experiences during the sessions, according to Dr. Bossis. “The more robust that mystical experience, the greater the outcome in terms of reduction of depression,” he said. “These aren’t NDE’s,” he added, “but they’re deathlike experiences with a similar phenomenology.”

Recent research shows that psilocybin is just one of many drugs that can induce NDE-like such experiences and suggests that those induced by ketamine, an anesthetic with hallucinogenic effects, show greater similarity to NDE’s than those induced by psilocybin. But “we only studied the phenomenological similarity between subjective experiences” and didn’t assess the extent to which any of the drugs might be effective treatments for depression, said Charlotte Martial, Ph.D., a neuropsychologist at the University of Liege in Belgium and another conference speaker.

Junger’s Brush with Death

Sebastian Junger’s brush with death came three years ago, following the rupture of an aneurysm in his pancreatic artery. As doctors rushed to stanch the bleeding that threatened his survival, he recalled, he encountered an “infinitely dark” pit that threatened to pull him in but also the welcoming “essence” of his beloved, long-dead father. “It wasn’t quite a vision. It was halfway between a vision and a feeling,” he said.

A self-described atheist whose father was a physicist, Junger said the experience nonetheless led him to reconsider his ideas not only about life and death but about the nature of the universe.

“I wish I could say I believe in an afterlife. I don’t. But I definitely have lost the certitude of my rationality,” he said, adding that he now believes it was possible that “some kind of energy or quantum phenomena” interacts with reality in ways we don’t understand.

If some see NDE’s as possible evidence of the supernatural or a phenomenon beyond the scope of scientific knowledge, others are convinced that they are simply the result of physiological processes—such as the oxygen starvation to the brain that can result from cardiac arrest.

There is a “perfectly natural explanation for NDE’s,” said Dr. Kondziella. “No need to postulate any supernatural events.”

But Raymond A. Moody, Jr., M.D., Ph.D., the keynote speaker whose remarks set the stage for the conference, expressed uncertainty over what near-death experiences actually represent.

Science? Or philosophy?

“I really just don’t know,” he said. “I think the questions that we are dealing with—a lot of them are not yet scientific questions,” he added. “I think they are philosophical questions.”

Dr. Moody is the author of the 1975 book “Life after Life” that sparked interest in near-death experiences. He has been documenting NDE’s for many years and is credited with coining the term near-death experience.

Uncertainty about life’s transcendent questions is inevitable, according to Karen Armstrong, a London-based author of numerous books on religious affairs and the other keynote speaker at the conference.

“Neither religion nor science can really respond. Ultimately, we are all in a ‘Cloud of Unknowing,’” she said in a reference to an anonymous 14th Century text on spirituality and Christian mysticism. “We are all just trying to find some meaning in it all,” she added, “without which we humans fall very easily into despair.”

For Brian C. Muraresku, the strange perceptions and complex emotions seen in near-death and similar visionary experiences are central to the human experience. “There’s something about that kind of experience—near-death, psychedelic, mystical, whatever it is—that holds the entire human race together.”

The New Wave of AI in Healthcare

In the healthcare field, artificial intelligence has the potential to improve everything from workflow efficiency to patient outcomes.

By Stephen Treffinger

Image Credit: Agne Sopyte
Members of the Organizing Committee. (From left to right) Affiliated with the Mount Sinai Health System: Christina Virgo, Esq., Sara Roncero-Menendez, Silke Muehlstedt, PhD, Thomas Fuchs, Dr. sc., Marc Kaplan; Affiliated with The New York Academy of Sciences: Melanie Brickman Borchard, PhD, MSc, Barbara Knappmeyer, PhD

Appearing on the front page of news outlets nearly every day, artificial intelligence (AI) is already transforming the world — and doing so at a staggering pace. In the healthcare field, it has the potential to improve everything from workflow efficiency to patient outcomes. But sifting through the hype can be a tremendous challenge.

The Windreich Department of Artificial Intelligence and Human Health at the Icahn School of Medicine at Mount Sinai and the New York Academy of Sciences hosted the ‘New Wave of AI in Healthcare’ symposium as a “call to action” — bringing together experts and leaders across the field to tackle this challenge through innovation, exchange, and collaboration.

Over the course of two days, May 23 and 24, 2023, researchers, academics, and industry leaders presented and discussed innovative research and clinical solutions with the potential to advance the capabilities of AI and to better serve patients and clinicians from diagnostics to long-term care. In their opening remarks, Nicholas Dirks, President and CEO of The New York Academy of Sciences, and Dr. Dennis Charney, Dean of the Icahn School of Medicine and President for Academic Affairs for the Mount Sinai Health System, challenged attendees to identify ways to utilize the enormous amounts of health data available to help predict, prevent, and develop more robust treatments for disease.

“Today, patients are dying not because of AI, but because of the lack of it,” stated Thomas J. Fuchs, Dr. Sc, Dean for AI and Human Health at Mount Sinai, lead member of the scientific organizing committee in opening the symposium, Dr. Fuchs further emphasized that although machine learning has already led to significant achievements across the field of healthcare, we are only at the beginning of an AI revolution in healthcare.

The two-day symposium featured sessions on foundational models that revolutionize diagnostics processes, infrastructural challenges to facilitate large-scale models and innovative deep learning solutions to deal with the petabytes of data generated in healthcare. Also, the symposium addressed ethical considerations for AI research in healthcare to eliminate bias and ensure its application is equitable as well as impactful.

Image Credit: Monika Graff
Panel Discussion: “Governance and Ethics for the Use of Large Healthcare Datasets for AI”. (From left to right) Panelists: Eric Lium, PhD, Mount Sinai Health System, Brandon D. Gallas, PhD, U.S. Food and Drug Administration, Emma Benn, DrPH, Mount Sinai Health System, Moderator: Eric Nestler, MD, PhD, Icahn School of Medicine at Mount Sinai

AI Fundamentals – Facts, Fictions, and Possibilities

Despite the immense hype around AI (as Dr. Fuchs remarked, “If you haven’t talked about ChatGPT, you’re probably living under a rock.”) and excitement in the start-up scene (including 14,000 healthcare startups in the AI realm), the reality is not quite as dramatic. There are only a few AI applications that are currently being used in the clinical setting to benefit patients. “While the FDA cleared hundreds of systems in radiology, in pathology, for example, there’s one single system that has proven to be safe and effective.”

Dr. Fuchs stated that AI gives us the possibility to truly democratize access to healthcare for the first time in history. “The AI we’re developing here and you’re developing at your fabulous institutions can be used in community clinics throughout the U.S. and throughout the world.”

The fact that clinicians are burned out and leaving practices has, according to several of the speakers, resulted in a deep crisis in healthcare. But AI is able to help combat this trend by automating workflows. One of the keynote speakers at the symposium, David C. Rhew, MD, Global Chief Medical Officer and VP of Healthcare at Microsoft, presented developments in Ambient Clinical Intelligence, which can, among other things, capture clinician-patient conversations and bring the information into the medical record.

“We have an ability now to pull data about individuals from every aspect. We can look at the perspective of what EHR [Electronic Health Record] data we have, what genomics data we have, and real-time data collection through remote monitoring.” This creates a 360-degree view of a person and one that changes as they evolve. “Now imagine having that at a population level,” he says. “That’s where the real power comes.”

Image Credit: Monika Graff
(From left to right) Dennis S. Charney, MD, Anne and Joel Ehrenkranz Dean of the Icahn School of Medicine at Mount Sinai, President for Academic Affairs, Mount Sinai Health System
Nicholas B. Dirks, PhD, President and Chief Executive Officer, The New York Academy of Sciences
Thomas J. Fuchs,, Co-Director of the Hasso Plattner Institute for Digital Health at Mount Sinai, Dean of Artificial Intelligence and Human Health, and Professor of Computational Pathology and Computer Science at the Icahn School of Medicine at Mount Sinai

AI for Healthcare and Life Sciences – Accelerated Discovery

Will more data and data-driven models yield better patient outcomes? This was a central theme throughout the symposium, which featured speakers utilizing foundational models in research and clinical diagnostic support tools to create deep learning models across heterogenous data modalities to improve patient outcomes.

The conference’s second keynote was delivered by Jianying Hu, PhD, from IBM Research and also an adjunct professor at the Icahn School of Medicine at Mount Sinai. In addition to IBM’s use of AI to drive accelerated discovery, she discussed what it means to go beyond large language models to apply foundational models to healthcare and life sciences research.

“In our view, [it’s] really all about enabling the journey from data to impact. AI can be used to help with the development of new molecular entities through novel generative methods, as well as computational screening tools [that] can be used to also identify new indications for drugs that are already approved,” says Dr. Hu. In addition to drug repurposing, AI is critical, she says, for being able to identify multimodal biomarkers.

From the Laboratory to Practice: Clinical Applications of AI

Moving from the theoretical to the practical and harnessing the full power of AI will require a change in approach, especially as it pertains to data: how much of it is required, how it needs to be treated, and how to maximize its effects. Abundant medical data is playing an important role, as precision medicine tries to determine the right treatment for the right patient at the right time.

“When we think about precision medicine and AI in medicine, we think about the health state of a patient and how we can model that health state of a patient,” says Gunnar Rätsch, PhD, ETH Zürich, who is currently conducting research as a visiting scientist within Mount Sinai’s AI Department.

Evidence of the health state comes from heterogeneous data modalities such as EHRs, pathology images, genomic profiles, drugs, and mobile health data. All of this data will have to be integrated into the computational representation to assess the true state of health of a patient. This requires new advances in AI approaches to exploit the specifics in the medical data, which requires genuine partnership between clinicians and machine learning/AI researchers.

Image Credit: Yovanna A. Roa, LMSW
Christina Virgo, Esq., Director of Operations Hasso Plattner Institute for Digital Health at Mount Sinai

The Impact of the New Era of Large-scale Deep Learning Models

Increasing the speed by which researchers can process and analyze vast amounts of data is an ongoing challenge in AI. The exponential growth of healthcare data, genomics, electronic records, and imaging can overload systems and slow the path to progress.

But processing capacity and speed aren’t the only issues. Another challenge is to better merge clinical medicine and data science, the two being mutually beneficial. Anthony Chang, MD, from the Children’s Hospital of Orange County, thinks this is an essential—albeit largely absent—duality. There are too few people who are educated on both sides of the equation.

Dr. Chang also sees the need for a shift to a new paradigm of databases, i.e. graph databases. “These are more three-dimensional and much more accommodating of the complexities of healthcare data. […] I can’t imagine we’re going to get a lot more dividends using deep learning healthcare without a change in how we look at databases, which is relational databases.”

In the detection of breast cancer, to cite one example, having very large scan sizes is advantageous, but dealing with these enormous images efficiently can be problematic due to the amount of memory in the GPU and other factors. Krysztof J. Geras, PhD, NYU Langone Health, discussed the particulars of multiple instance learning. “We have this ability to indicate those parts of the image that are important. We can actually look at this image with greater detail with a higher capacity network, but just at a certain region of it, and then we can fuse this information. And that works amazingly well.”

AI at Mount Sinai

The Mount Sinai Health System is dedicated to leading an AI-driven transformation of healthcare through innovative research, pioneering clinical care, and personalization for each patient, aiming to have a wide-reaching impact on human health. In 2021, Mount Sinai established the Windreich Department of Artificial Intelligence and Human Health, the first department focused on AI and Human Health in any medical school in the United States.

As a leader in the AI in healthcare space, researchers at Mount Sinai are building an “intelligent fabric” of AI that will underpin all interdisciplinary efforts, combining AI, computer science, machine learning, and data science across the Health System to support every individual who comes through the hospital doors for care, as well as nurses, physicians, scientists, hospital operations and leadership,

Several Mount Sinai researchers presented their AI-integrated research during the symposium, highlighting the various ways in which this new technology can benefit researchers, clinicians, and patients from diagnosis to treatment, developing some of the most exciting advances in the field.

Highlights that were presented include:

  • Ipek Ensari, PhD, who works with AI and machine learning combined with statistics in the field of women’s health, noted the possible link between indicators in the female reproductive system to diseases such as coronary artery disease, and stroke.
  • Hayit Greenspan, PhD, focuses on AI in the medical imaging space. “We are developing a platform that provides tools for collection of the data, support of annotation of the data, and support of modeling that can be done to extract information that is useful from the imagery data.”
  • Xiaosi Gu, PhD, focuses on the fast-growing sub-sector of mental health in health tech. “We need to both achieve a mechanistic understanding of the brain and of the mind at the algorithmic level and to use brain-related data to try to create predictive models.”
  • John F. Crary, MD-PhD, is a neuropathologist and runs a research lab in neurodegenerative diseases. “Alzheimer’s is a monumental public health crisis. It’s really important […] to get […] tissues digitized, organized, and made available to scientists and computational people.”
  • Bruce J. Darrow, MD-PhD, who leads Mount Sinai’s AI ethics committee, often works on creating spaces and treatments that are not only safe and effective, but also equitable, being tested across the right demographics and taking into account factors such as insurance coverage, income, and zip code.
  • Robert Freeman, RN, MSN, NE-BC, is working on moving from the reactive to the predictive and preventative AI. In practice, this would lead to shorter patient time in the hospital and improved overall 30-day mortality.
Image Credit: Monika Graff
(From left to right) Thomas J. Fuchs,, Mount Sinai Health System, Keynote Speakers: Jianying Hu, PhD, IBM Fellow, Director, HCLS Research, Global Science Leader, AI for Healthcare at IBM Research, David Rhew, MD, Global Chief Medical Officer, Vice-President of Healthcare, Microsoft

Governance and Ethics for the Use of Large Healthcare Datasets for AI

The use of massive amounts of patient data for AI naturally raises key governance and ethics issues, including data privacy, transparency, regulatory compliance, and bias screening to ensure fair representation. These issues and more were covered in a panel discussion moderated by Dean Eric Nestler, MD, PhD, Icahn School of Medicine at Mount Sinai.

The role of bias in large healthcare data models can take many forms, especially when it comes to populations of color and members of underrepresented communities. One of the panelists, Emma Benn, DrPH, a biostatistician at Mount Sinai who applies her training to health equity research, addressed the governance and ethics of the topic. In terms of race, she posed the question of whether the algorithms and technology are just describing racial and ethnic differences versus being able to operationalize race in a way that gets closer to identifying mutable targets for intervention.

“If we’re not operationalizing things correctly, we’re not going to be able to use AI to reduce health inequalities,” says Benn.

Another panelist, Dr. Erik Lium, PhD, discussed the importance of data privacy. Dr. Lium is the Chief Commercial Innovation Officer for the Mount Sinai Health System and the President of Mount Sinai Innovation Partners. One question posed by the audience was which processes a hospital uses to protect a patient’s personal health data. The answer depends on who is going to use said data, be it internally for research or with an external partner. Internally, an institutional review board decides acceptable usage. For use with external partners, it involves legal agreements with copious protections that bar anyone from taking, for instance, de-identified data and attempting to re-identify the data.

“You can use the data for a stated purpose that we think is ultimately beneficial to patients. If you go outside of that purpose, then you’re doing something that’s inappropriate,” says Dr. Lium.

Keynote speaker Dr. David Rhew ended his address on a key philosophical and ethics-focused note, bringing up the idea of AI taking a pause to prevent potentially harmful aspects such as the spreading of misinformation. “If the good actors pause on this, that doesn’t mean that the bad actors are going to pause.”

In Conclusion

Throughout the symposium, speakers were able to address successes, challenges, and future initiatives needed to further the development of new AI technology in the field and how it can be implemented to better patient outcomes. Some of the key takeaways from the symposium’s sessions include:

  • Increasing cooperation between institutions.
  • Figuring out how to obtain and efficiently process ever larger data sets.
  • Using AI to enhance patient experience and outcomes.

Finally, these developments will need to be carefully and continuously filtered through the lenses of equitability and security to ensure that every patient receives the highest level of care no matter the setting. The ‘New Wave of AI in Healthcare’ symposium was an important step towards this equitable, AI-integrated future, with more advancements and discussions to come.

How to Make Your Junior Academy Application Shine

A shot of a CV.

Each year we seek out passionate STEM-interested students from around the world to join our signature high school research program. Here are four smart tips that will give your application an edge.

Through the Junior Academy of The New York Academy of Sciences, high school students ages 13-17 develop research, innovation, and collaboration skills. They leverage these skills to compete in Innovation Challenges sponsored by industry-leading companies, where they work under the guidance of a STEM professional. In order to participate, students must have access to a computer, phone or tablet, an internet connection, and a global mindset, as Junior Academy teams are composed of a cohort of students from different countries all over the world.

It’s a very unqiue STEM learning experience, and every year, we seek out passionate high school students interested in STEM to join. If you’re a student who wants to apply, keep these tips in mind for how to make your application shine.

Tip #1: Be thoughtful about your answers to the essay questions.

The Junior Academy is looking for what makes you unique. Is there something that makes you stand out in school or extracurricular activities?

When writing your responses, be clear and concise. You only have 500 words to complete each question; but if you can get your point across in fewer words, don’t feel like you have to use all the space. Proofread your answers carefully. Ask a friend or family member to read your answers before you submit the application—they may spot an error you missed.

Tip #2: Talk about the personal challenges you’ve overcome.

When you’re part of the Junior Academy, you’ll be using creative problem-solving skills. That means overcoming obstacles in your path. We’ve all faced obstacles in our lives, so tell us about a tricky situation you faced and how you handled it. For example, did you ever have a report, a test, and a project all due in the same week? If so, how did you complete them all to the best of your ability? Or, have you ever made the team after previously having been rejected? How did you regroup and succeed the second time around? Stories of perseverance and resilience are what we want to hear.

Tip #3: Show us you’re a team player.

When you work on an innovation challenge, you will collaborate on a team of two to six people. Share a time that you’ve worked with a team towards a common goal. Did you have a particular skill that you brought to the table? Let us know what it is.

Tip #4: Explain how you’ll be able to meet the time commitment.

You’ll need work with your team three to four hours a week on your challenge solution. How will you balance this with your academics, other extracurricular activities, and personal life?

Learn more about the Junior Academy.

Read about some of our past Junior Academy winning teams here and here.

What Really Happens After Cardiac Arrest?

An illustration of a human heart.

Published December 06, 2019

Speakers from left to right: Sam Parnia, MD, PhD (Director of Critical Care & Resuscitation Research at the NYU School of Medicine), Sarah Perman, MD (University of Colorado School of Medicine), Tom Aufderheide, MD, MS, FACEP, FACC, FAHA (Medical College of Wisconsin), Sonja Lyubomirsky, PhD (University of California, Riverside), and Stephan Mayer, MD, FCCM (Wayne State School of Medicine)

We see it in television dramas all the time—a patient in cardiac arrest is rushed into the ER after a severe traumatic injury or medical emergency, with a staff of medical professionals frantically performing CPR. Tension is high and doctors have to figure out how to save the person’s life. Beyond the theatrics of primetime drama, the field of medicine has been making major strides to reverse cardiac arrest and death.

In this video you’ll hear directly from top physicians and researchers who are at the cutting edge of resuscitation science. Moderated by Sam Parnia, this discussion brought together internationally-recognized researcher in emergency cardiac care, Tom Aufderheide; distinguished happiness research psychologist, Sonja Lyubomirsky; world expert in neurological intensive care Stephan Mayer; and Sarah Perman, a leader in resuscitation science and post-cardiac arrest care.

Want to hear more cutting-edge science distilled for the public? Check out the final event in our three-part series, “The Power of Wonder: Modern Marvels in the Age of Science.”

What Can Science Tell Us About Death?

Sam Parnia smiles for the camera, wearing a suit and tie.

Sam Parnia, a leading expert in resuscitation science research, explains how death is not an absolute, but a process, and what happens when patients experience death.

Sam Parnia MD, PhD

By Robert Birchard

Across time and cultures, people have been conditioned to view death as an endpoint to the experience of life. However, advances in resuscitation science and critical care medicine have challenged assumptions about the finality of death. Sam Parnia, Director of the Critical Care & Resuscitation Research Division of Pulmonary, Critical Care & Sleep Medicine at New York University Langone Medical Center, recently spoke to The New York Academy of Sciences about his resuscitation science research. Dr. Parnia’s work illuminates how death is not an absolute, but a process, and what happens when patients experience death — sharing insights from his research in his own words:

What is death?

Death occurs when the heart stops beating. We call this death by cardiopulmonary criteria and it is how death is defined for more than 95 percent of people. A person stops breathing and their brain shuts down, causing all life processes to cease. More recently with the birth of modern intensive care medicine and the ability to artificially keep people’s hearts beating, doctors like myself can keep a patient’s heart beating longer.

Where people may have suffered irreversible brain damage and brain death, this leads to a situation where the brain has died, but the person’s heart is still beating, so legally, they are declared dead based upon irreversible brain death, or death by brain death criteria. This happens in a small fraction of the cases where people are declared dead.

For millennia death was considered an irreversible event and nothing could restore life. During the last decade, we’ve realized it’s only after a person has died that the cells inside their body, including the brain, begin their own death process. We used to think that you had five or 10 minutes before brain cells died, from a lack of oxygen, but we now know that’s wrong.

You have hours, if not days, before the brain and other organs in the body are irreversibly damaged after death. It’s actually the restoration of oxygen and blood flow back into organs after a person’s heart stops, but is then resuscitated that paradoxically leads to accelerated cell death. So, this accelerated secondary injury process is what we need to combat in medicine now.

Why is the term “near-death” experience inaccurate?

The problem with this term is that it is inconsistent with what people actually experience. It is undefined and imprecise. If I said ‘an airplane was involved in a near-miss incident,’ what does that mean? Did you have another plane come in within an inch of another plane, or were they a mile away? The term is ill-defined, and, it doesn’t take into consideration the fact that a lot of people have biologically died and returned.

What is a death experience?

I call it an “experience of death” because that’s what it is. People report a unique cognitive experience in relation to death. They may have a perception of seeing their body and the doctors and nurses trying to revive them, yet feel very peaceful while observing. Some report a realization that they may have actually died.

Later they develop a perception or a sensation of being pulled towards a type of destination. During the experience, they review their life from birth, until death, and interestingly this review is based upon their humanity.

They don’t review their lives based on what people strive for, like a career, promotions, or an amazing vacation. Their perspective is focused on their humanity. They notice incidents where they lacked dignity, acted inappropriately towards others, or conversely, acted with humanity and kindness.

They re-experience and relive these moments, but also, what’s fascinating, which sort of blows me away because I can’t really explain it, is they also describe these experiences from the other person’s perspective.

If they caused pain, they experience the same pain that other person felt, even if they didn’t realize it at the time. They actually judge themselves. They suddenly realize why their actions were good or bad, and many claim to see the downstream consequences of their actions.

How do studies of cardiac arrest  inform the debate on the nature of consciousness?

Traditionally, researchers had proposed that mind or consciousness – our self – is produced from organized brain activity. However, nobody has ever been able to show how brain cells, which produce proteins, can generate something so different i.e. thoughts or consciousness. Interestingly, there has never been a plausible biological mechanism proposed to account for this.

Recently some researchers have started to raise the question that maybe your mind, your consciousness, your psyche, the thing that makes you, may not be produced by the brain. The brain might be acting more like an intermediary. It’s not a brand new idea. They have argued that we have no evidence to show how brain cells or connections of brain cells could produce your thoughts, mind or consciousness.

The fact that people seem to have full consciousness, with lucid well-structured thought processes and memory formation from a time when their brains are highly dysfunctional or even nonfunctional is perplexing and paradoxical.

I do agree that this raises the possibility that the entity we call the mind or consciousness may not be produced by the brain. It’s certainly possible that maybe there’s another layer of reality that we haven’t yet discovered that’s essentially beyond what we know of the brain, and which determines our reality.

So, I believe it is possible for consciousness to be an as of yet undiscovered scientific entity that may not necessarily be produced by synaptic activity in the brain.