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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.”

In Step with the UN on Science for Sustainable Development

For a United Nations discussion of the role of science in solving the world’s most urgent problems, the International Science Reserve (ISR) convened a panel of experts from the ISR network, across academic, private and public sectors. The recording is now available on-demand (viewing instructions below). 

The panel was moderated by Mila Rosenthal, Executive Director of the International Science Reserve, and included:  

  • Nicholas Dirks, President & CEO, New York Academy of Sciences, ISR Executive Board Co-chair 
  • Erwin Gianchandani, Assistant Director for Technology, Innovation and Partnerships National Science Foundation, Federal Liaison to the ISR 
  • Tracy Marshall, University of the West Indies St. Augustine Campus. Trinidad and Tobago, ISR Science Community Member 
  • Philip Nelson, Director, AI for Social Good, Google AI, ISR Executive Board Member 

The webinar was part of the United Nations General Assembly’s Science Summit, where we discussed how the ISR can help in fast-moving climate and health-related crises to protect progress on the UN Sustainable Development Goals – the Global Goals – and limit the damage to communities and habitats.

Mila Rosenthal (ISR) introduces the Sustainable Development Goals (SDGs) and their relationship to crises.

When a crisis hits, the International Science Reserve will help scientists in our network get additional access to specialized human and technical resources, like remote sensing, geospatial mapping and high-performance computing, so that they can apply their research for crisis response.

Here are two big takeaways from the discussion:

1. Human networks are key, and they need to include everyone to make sure that science and technology is aimed at helping the most vulnerable people and most fragile environments.

Erwin Gianchandani (NSF) on how the ISR democratizes access to resources.
Philip Nelson (Google AI) on the power of coming together.
Tracy Marshall (University of the West Indies – St. Augustine Campus) on how the ISR will support her work as a scientist. 

2. You can’t just throw money at a crisis and expect rapid response solutions.  You have to learn from previous experiences and prepare in advance. 

For example, the ISR is keeping the life-saving public-private connections made during COVID-19 alive in order to prepare for the next crisis. 

Erwin Gianchandani (NSF) on why networks are just as important as money in times of crisis research.
Nicholas Dirks (NYAS) on collaboration between the public and private sector during crisis.
Tracy Marshall (University of the West Indies – St. Augustine) on valuing local contexts in disaster management research. 
Philip Nelson (Google AI) on solving crisis-related problems in an open environment. 


Do you want to watch the whole webinar? Here are three steps to rewatch the panel through the ISR Science Unusual series on-demand:   

  • Register for the webinar using this link  
  • Then, click “Join Event”  
  • After logging in, select the “Schedule” menu, or the grid menu (small squares) on mobile, located at the top of your screen, then click “On Demand” 

Scientists Hunt for Clues to Post-Wildfire Recovery in Argentina  

In August, wildfires ripped through the Córdoba Province in central Argentina, leaving economic damage and a scorched forests and pasture land in its wake. Argentina is no stranger to wildfires, but climate change is making the fires more frequent, widespread and complex – and the impacts of drought and fires are stretching across borders.  

After thousands of acres in northern Argentina burned in February of 2022, ash clouds flew into Argentina’s neighbor, Paraguay, harming local residents’ health with smog-filled air. The country made international headlines just two years prior when another set of fires in Córdoba burned 60,000 hectares of flora, fauna, grassland, forests, and homes.  

Healthy farmland and soil are critical to the region, given that it relies heavily on its agricultural industry, like cattle farming. Crisis after crisis has forced the region’s leading scientists to rethink how fire-driven changes to soil properties implicates vegetation, plant regeneration and ecosystem services. And it has pushed them to work together across borders and scientific disciplines.  

“In late September 2020, it was easy to see from the Córdoba City the thick black plumes of smoke rising from the ranges, while hellish images were shown on TV and social media,” said Dr. Maria Gabriela Garcia, International Science Reserve community member and a geologist based in Córdoba. “This situation led me to wonder to what extent the fires have altered the chemical and physical properties of the soils, and ultimately, impacted their fertility and runoff control capacity.” 
After the 2020 fires, Argentina’s National Council of Science and Technology (CONICET) called researchers together from different disciplines to propose actions and lines of research that deal with different aspects of this crisis. Today, geologists, mineralogists, chemists, microbiologists and ecologists, are all working all together to rapidly characterize the dynamics of post-fire recovery.  

One unique collective of Argentinian scientists are on the hunt for stronger data about the soil in the aftermath of extreme wildfires. Through the NCST, Dr. Estela Cecilia Mlewski, a microbiologist, met Dr. Garcia, a professor at the National University of Córdoba. 

The team also brought on Edith Filippini, a lichenologist focused on ecological studies and biomonitoring of environments affected by fire; Romina Cecilia Torres – a specialist in postfire regeneration by resprouting and seedlings; and Daihana Argibay – a specialist in satellite image analysis. 

The group’s collected data will be fundamental to understanding the geochemical and microbiological disturbances that occur in soils of a semi-arid mountainous area of southern South America affected by forest fires, and help researchers design effective strategies for remediation of the affected ecosystems across the region. If their research can find the presence of microorganisms, for example, there is an opportunity for regrowth and regeneration of local flora – which could lessen the fires’ impact on farming or other ecological or economic activities. 

The group recently worked together on the International Science Reserve’s readiness exercise on wildfires. The ISR conducts readiness exercises – or scenarios – to bring scientists from across borders and disciplines together to prepare for crisis. The Argentinian scientists believe that the International Science Reserve can be useful for giving researchers the tools for fire prevention and support through much needed resources to predict fire behavior, and help in control and monitoring tasks against a crisis.  

“The ISR is an excellent opportunity to know researchers around the world working on similar aspects to us. It gives us the potential to generate collaborations between foreign groups and enrich our knowledge. The ISR’s readiness exercises can improve existing tools and more importantly, expand our ideas,” Dr. Mlewski recently told the ISR team in an interview. 

If you are interested in joining the International Science Reserve network and collaborating with scientists like the Argentinian group, please visit our sign-up page to learn more about becoming a member of the ISR community. 

How This Teacher Used STEM to Spark Interest in Social Studies

A woman poses for the camera with NYC's Brooklyn Bridge in the background.

By Roger Torda

Servena Narine outside her classroom at PS 307 in Brooklyn

Servena Narine, who teaches at a New York City public school in Brooklyn, uses science, technology, engineering, and math (STEM) skills to help her elementary school students master their social studies curriculum.

This summer, Narine used time made available because of the COVID-19 shutdown to take The New York Academy of Sciences’ online course STEM Education in the 21st Century. During the eight-week course, she designed a curriculum for fourth-grade students. One of the units called for students to use data analytics in creating an infographic to “tell a story about the effects of immigration on New York City’s industrial growth in the 1900s.”

The Seven Essential STEM Skills

“It was a course where we incorporated seven essential STEM skills into our teaching,” Narine said in a recent phone interview. “I think sometimes as teachers we do that naturally, but through the course I was able to more deeply integrate the STEM skills into my lesson plans.”

Narine was referring to seven skills Identified by the Academy’s STEM Education Framework. critical thinking, problem solving, creativity, communication, collaboration, data literacy, and digital literacy and computer science. These skills form the foundation of the course.

“The Academy developed its Framework back in 2016 as a research-based tool that can be used to ensure students receive high-quality STEM learning,” said Chris Link, the Academy’s Director of Education. “Our online course coaches teachers on strategies they can use to help their students build critical 21st-century skills.”

“Eight years ago, my school became a magnet school for STEM studies,” Narine explained, referring to PS 307, which serves pre-K through fifth grade in the Vinegar Hill neighborhood of Brooklyn. “I’m always looking to learn more about what it means to be a STEM school, and what it means to integrate the principles of STEM into the classroom. When I saw that this course was available, and that it was free, and that I had time on my hands because everyone was self-isolating because of COVID-19, I jumped right into it.”

Continuing Teacher and Leader Education

Narine was one of 100 New York City teachers enrolled in the course through the sponsorship of Medidata, which has supported several Academy STEM programs. Narine and other teachers who completed the course received 30 Continuing Teacher and Leader Education (CTLE) credits required by New York State to maintain certification.

“I loved that the course was asynchronous, so I could set a schedule for myself,” Narine said. “The participants, the other teachers, all reviewed each others’ work, and offered feedback. That was a great benefit. And I loved that for each of the seven skills there was an expert in the field who was able to share information.

Narine’s course not only incorporated STEM skills, but aligned closely with the state’s Passport to Social Studies curriculum. To develop critical thinking skills, one of her units calls on students to analyze documents from the Colonial and Revolutionary War periods. A unit on problem solving asks students to develop solutions to clashes between Native Americans and colonists.

Cross-Interdisciplinary Skills for Students

A unit on the geography of New York calls for creativity in designing maps to promote tourist destinations. Yet another unit is designed to promote collaboration skills as teams make a game to test knowledge of material covered in earlier units. These cross-disciplinary skills serve students in their social studies classes, their STEM classes, and beyond.

“The curriculum asks students to look at Native Americans as the first inhabitants of New York State,” Narine said, explaining how she started thinking about a unit that would focus on communication skills, another area of focus in the Academy’s online course.

“I remember thinking that we’d be learning about Native Americans in the region around the time we’d be celebrating Thanksgiving,” she continued. “And I thought it would be nice to have the children create a public service announcement to give thanks to Native Americans for the contributions they have made to New York State and to our society, rather than the other way around, where we pretty much look at the European influence and teach that it is because of the Europeans that we have Thanksgiving. I said, ‘Let’s turn it around and say thank you to the first inhabitants of New York for their contributions.’”

Brightest International Young Scientists Reach for the Stars

By Hallie Kapner

When Japanese physicist Kumiko Hayashi of Tohoku University and neuroscientist Ephraim Trakhtenberg of the University of Connecticut met at the New York Academy of Sciences this year, the synergies between their work weren’t immediately obvious. The two scientists were paired together as part of the Interstellar Initiative, a joint project of the Academy and the Japan Agency for Medical Research and Development (AMED), which grouped 50 early-career scientists from around the world for interdisciplinary research projects.

“The biggest global challenges, whether in health, the environment, or energy, require scientists with different expertise to work together,” said Academy President & CEO Ellis Rubinstein. “The Interstellar Initiative brings together brilliant young scientists who would likely never cross paths, and supports them as they develop solutions to major health issues.”

Devising New Therapies

Hayashi and Trakhtenberg are devising new therapies to restore neuronal function following injury. As human cells mature, their ability to replicate is severely reduced. This phenomenon is especially prevalent in the brain, where the creation of new neurons exists only at very low levels in adulthood, and Trakhtenberg’s work suggests that motor proteins may be involved in this loss.

“If we can understand the dynamics of these proteins, we may be able to reverse the process,” he said. Over the past several years, Hayashi developed novel algorithms that can be applied to motor protein measurement and analysis. “I don’t know much about neuroscience,” she said, “but it turns out that my algorithms can illuminate some mechanisms of the brain.”

From left to right: President Suematsu, Japan Agency for Medical Research and Development (AMED), recognizes the collaborative work of Japanese physicist Kumiko Hayashi, Tohoku University and neuroscientist Ephraim Trakhtenberg, University of Connecticut, along with Ellis Rubinstein, President and CEO, New York Academy of Sciences at the recent Interstellar Initiative workshop presented by AMED and the Academy.

International Collaboration

This teamwork is precisely what AMED president Makoto Suematsu envisioned creating through the Interstellar Initiative, part of a broader strategy to bring international partnerships and new funding streams to Japan’s R & D pipeline. As technological advances that enable data sharing and ease remote collaboration have become ubiquitous, Suematsu believes it is crucial for Japanese researchers to join global research efforts.

“International collaboration is critical in many fields,” Suematsu said. “From infectious disease outbreaks to cancer treatment and drug development, we can accomplish much more when we reach out, shake hands and collaborate.”

Cancer Research

Another Interstellar Initiative team, comprised of NYU biologist Carlos Carmona-Fontaine, oncologist Valerie Chew of Singapore Health Services and physicist Shuichi Shimma of Osaka University, is juggling large time differences and global transport of perishable patient samples as they pursue their project. Blending Chew’s expertise in oncology with Carmona-Fontaine’s efforts to understand the role of metabolites in cancer cells and Shimma’s imaging techniques, the group is uncovering the interplay of metabolite activity and immune changes in tumor cells.

Noting that the Interstellar Initiative breaks down barriers that inhibit cross-disciplinary partnerships, Carmona-Fontaine commented that scientists “usually stick to our own communities, and there’s often a disconnect between scientists from different parts of the world — yet there are many advantages to learning different ways to look at a similar problem.” Chew was thrilled to be paired with teammates who brought both new expertise and new technologies. “If you’re working in your own zone, you’ll do what’s familiar,” she said. “But bringing together different disciplines and technologies creates a novel, creative environment for solving problems.”

Realizing Applications For Their Research

Proposals devised by Interstellar Initiative teams will be submitted to international funding agencies. For physician and biologist Deepak Lamba and biologist Akira Satoh, such funding may help them realize applications for their research. Lamba, who is developing methods for using stem cells to repair retinal tissue, is working with Satoh, whose research is illuminating the regenerative pathways of amphibians. They are probing the factors that influence regenerative capabilities in mammalian and amphibious cells, with the hope of developing methods of repairing and regenerating damaged tissue.

“[Stem cell research is] moving so quickly that I think we’ll start seeing applications in the not-so-distant future,” Lamba said. Satoh noted that stem cell research is less popular among Japanese scientists, while Lamba added that few labs in the US are using amphibians to study regenerative pathways. “We would never have done this on our own — it’s a unique challenge for us to do together.”

Rubinstein is quick to highlight that this is just the beginning for the Interstellar Initiative. “This is only our first cohort, and there’s so much exciting research in the works already,” he said.