Sign up for The Post’s Top News newsletter and get the Post’s most important and interesting stories.
Miasha Gilliam-El, a 37-year-old nurse and mother of six, fell to her knees and suffocated outside her home in Midlothian, Virginia. She was loaded into an ambulance and told “I can’t die like this,” passing out after hospital emergency personnel cut off her clothes to assess her breathing.
What happened next happened to thousands of people who came back from the brink of death, their stories filled with strange visions and journeys that challenged science as we know it. Last year, a team of researchers from Belgium, the United States, and Denmark launched an ambitious effort to try to explain these experiences at a neurobiological level—work that is now being questioned by two researchers in Virginia.
The questions at stake are almost as old as humanity, involving the possibility of an afterlife and the nature of scientific evidence – questions that are likely to take center stage at a conference of brain experts in Porto, Portugal, in April.
Gilliam-El recalled February 27, 2012, the day she developed a rare disease called peripartum cardiomyopathy. For reasons that are not entirely understood, a woman’s heart muscle weakens and enlarges between the last month of pregnancy and five months postpartum, putting her at risk for heart failure.
Gilliam-El, who had given birth three days earlier, recalled watching a doctor try to insert a tube down her throat to open her airway. She remembers staring into a machine that displayed the electrical activity of her heart and noticing that her body was flattened. Her breathing stopped.
“Then it was like I was transported to another place. I was kind of sucked back into the tunnel,” she said. “It was so peaceful in this tunnel. I was just walking, holding someone’s hand. All I heard was the scripture, ‘Yea, though I walk through the valley of the shadow of death…'”
Although neuroscientists have learned more and more about the inner workings of the brain in recent decades, near-death experiences like Gilliam-El’s remain a profound mystery.
Writing in Nature Reviews Neurology last year, a team of researchers led by Charlotte Martial, a neuroscientist at the University of Liège in Belgium, synthesized some 300 scientific papers and focused on the commonalities of the experience of looking at one’s body from the outside, walking through a tunnel into brilliant light, and experiencing a profound sense of calm. The authors linked these experiences to specific changes in the brain, creating a groundbreaking model called NEPTUNE (Neurophysiological Evolutionary Psychology Theory for Understanding Near-Death Experiences).
Researchers Bruce Greyson and Marieta Pehlivanova of the University of Virginia School of Medicine present a comprehensive critique of the Neptune model in the journal Psychology of Consciousness: Theory, Research, and Practice.
While calling the model an “admirable strategy,” they wrote that aspects of such experiences cannot be explained by brain physiology alone, and they criticized the Neptune authors for omitting evidence that did not support their ideas.
Although this debate is taking place in the rarefied atmosphere of scientific journals and conferences, it is almost certainly something that most people have thought about.
“This is not the digestive function of some lower life form that we are talking about here. These effects affect all of humanity,” said Jeffrey Long, a radiation oncologist and co-author of the 2011 book “Evidence of the Afterlife: The Science of Near-Death Experiences.”
“Do we have evidence?” he asked. “How strong is the evidence that there is life after death, that our consciousness survives physical death?” Long, who was not involved in the Neptune paper or criticism, said he has studied more than 4,000 near-death experiences.
Several studies cited by the Neptune researchers suggest that approximately 10 to 23 percent of near-death experiences occur after a heart attack, 15 percent after a long-term stay in intensive care, and 3 percent after a traumatic brain injury. Others occurred after electrocution, near-drowning and complications during childbirth.
“For most of them, it’s a life-changing experience,” Martial said. “Generally speaking, they are not too afraid of death [afterward].” They often develop a greater interest in spirituality and are able to become more compassionate toward others, she said.
To create the Neptune model, the scientists examined changes in gas concentrations in the brain’s blood vessels: a decrease in oxygen and an increase in carbon dioxide that occurs before and during cardiac arrest.
They cite research that suggests out-of-body-like sensations may occur at the temporoparietal junction, a higher-order hub that processes sensory information and helps differentiate between self and others. Research suggests that electrical stimulation of this area, located behind and above the ear, may trigger out-of-body experiences, they write.
Their analysis incorporated observations of brain chemicals, including nerve cells and chemical messengers that regulate mood, sleep and learning. Martial said the model is intended to be a living document that can be modified as scientists learn more.
But Grayson and Pelivanova dispute key aspects of the model. The hallucinations induced by the electrical stimulation were “completely different from the visions of deceased people reported in the literature,” they wrote. [near-death experiences]”. For example, one study reported that patients would hallucinate that there was a person behind them, but they could not see or hear it.
“This is simply not comparable to the vision reported in many reports. [near-death experiences] Grayson and Pelivanova, professor emeritus of psychiatry and neurobehavioral sciences and assistant professor of psychiatry and neurobehavioral sciences, respectively, wrote:
The pair acknowledged that near-death experiences are “often triggered by physiological events” but stressed that such events do not fully explain the experiences people describe. They accuse the authors of Neptune of dismissing evidence from patients’ near-death narratives, as well as evidence from hospital staff that supported certain aspects of those narratives – for example, the number of people in the room during resuscitation.
Scientists are divided over whether the stories patients tell constitute reliable scientific data.
Grayson said there have been descriptions of near-death experiences since ancient times. Researchers have been collecting and discussing accounts since at least 1892, when Swiss mountaineer and geologist Albert Heim discussed the stories he had collected since his brush with death while climbing the Alps.
By their nature, these reports can be difficult to define and even more difficult to analyze with scientific rigor. In a 1983 paper, Grayson described a 16-item scale he developed to measure descriptions of near-death experiences and to standardize research on them.
But efforts to impose rigor on the study of near-death experiences have forced researchers into troubling territory that straddles the boundaries of science and spirituality.
“These stories are seductively powerful narratives that give hope to our deepest longings for consciousness after death,” Kevin Nelson, professor emeritus of neurology and retired medical staff affairs director at the University of Kentucky Health Care, wrote in an email. “I share that hope, but with wax in my ears and science strapping me to the mast, I will not succumb to the siren’s song.” (Nelson is one of the authors of the Neptune paper.)
Neptune researchers may dismiss the testimony of patients who were near death, Grayson said, “because it’s not evidence, but the fact is that every scientific discovery begins with subjective observation and may ultimately be corroborated by controlled experiments.”
In addition to testing aspects of the Neptune model, Grayson and Pelivanova write, “it is also important to remain open to other potential causes, whether currently unknown or not fully understood.”
Out of necessity, most previous studies have involved researchers returning to patients after near-death experiences to collect their narratives and medical records. But such retrospective studies are biased in how people remember these events and share their experiences with others.
However, Neptune researcher Martial said she and three colleagues at the University Hospital of Liège are conducting a prospective study that involves following patients from the moment they are taken to the hospital’s resuscitation room. It will involve video footage recorded in the hospital and electroencephalography, which measures the brain’s electrical activity.
“When we die, it’s a process – not just an event,” Martial said. “For example, during a cardiac arrest, we have less oxygen, which causes less brain activity. But actually, at some point, we see an increase in electrical activity in the brain, and then we can observe a kind of flat line.”
Nurse Gilliam-El remembers her near-death experience ending when a powerful voice told her “not yet,” and she felt like she was back in her body. In the bright ward, everything seemed blurry.
She worried that if she told anyone what happened, they wouldn’t believe her.
Related content
