Near-death experiences have long fascinated both scientists and ordinary people. These powerful and mysterious moments often occur when someone is close to dying or has been brought back after their heart stops. Survivors describe them as vivid and emotional, filled with lights, voices, or a strange sense of leaving the body. But what truly happens to the human brain during these final moments remains one of the most intriguing questions in neuroscience.
Researchers believe that these intense events could be the brain’s natural response to extreme stress. When a person faces life-threatening danger, the mind may create visions or sensations that feel spiritual or otherworldly. Although science has made great progress in understanding the body’s process of dying, what the mind experiences in those last seconds is still largely unknown.
For many people who survive cardiac arrest, near-death experiences leave a lasting impression. They often speak about seeing a bright light, floating above their body, or feeling a presence that seems beyond this world. While each story is unique, the pattern is remarkably similar across cultures, ages, and beliefs.
One of the most striking stories that captured public attention is that of Tom Kearney, a man who had an unforgettable experience after a terrible accident.
Tom Kearney’s life changed forever just before Christmas in 2009. While walking in London, he was suddenly hit by a bus. The crash was so severe that it caused massive injuries to his head and lungs, leaving him in a deep coma. Doctors fought to keep him alive, and for two long weeks, his family and friends waited in fear.
During this time, Tom’s body was unconscious, but his mind was somewhere else entirely. What he experienced while in the coma would later shock both him and the people around him.
When Tom finally woke up, he claimed that he had seen people who had already passed away. It was as if he had entered another world, one that felt both familiar and unreal. His story became one of the most detailed personal accounts of near-death experiences ever shared with the media.
In his vision, Tom first found himself in Ireland, inside his great-grandfather’s old house. It was a place filled with memories from his childhood. There, he saw his grandparents, who had died years earlier. They looked just as he remembered them, warm and kind but serious at the same time.
They spoke to him directly and told him that he was not supposed to be there. Their words confused him. Tom felt torn between the comfort of seeing them again and the strange message they kept repeating. He realized that something was not right, that perhaps he did not belong in that place.
Before he could ask more questions, he was suddenly transported to another scene. A gate appeared, and as he passed through it, he found himself in New York City at his in-laws’ house. The experience felt real, as though he had physically traveled there.
Inside the house, his late mother-in-law was waiting for him. She looked surprised and worried when she saw him. “You’re not supposed to be here,” she told him. “You should be with your wife and your boys. Did something happen?”
Tom tried to explain that he had been hit by a bus, but she kept insisting that he needed to leave. Her final words echoed in his mind: “Please go home.”
After that, Tom said he met several other deceased relatives, and every single one of them gave him the same message. They all told him to return, that it was not his time yet.
While in the coma, Tom could also hear the voices of people who came to visit him in the hospital. His wife, his friends, and his family spoke to him every day, even though they thought he could not hear them.
“My wife talked to me every single day,” he recalled. “She brought friends and family to see me, and they all talked to me.”
He described how important this was for him during his coma. It helped him stay connected to life, even when he was deeply unconscious. He compared it to being in an underwater submarine, trying to navigate using only sound.
Inside his mind, he built what he called a “thought world.” In this world, time felt fluid. He moved between memories, places, and moments that felt like dreams but were filled with meaning. After waking up, he said those experiences stayed with him as vivid dream-like memories.
Not all near-death experiences are as peaceful as Tom’s. Many survivors describe frightening or confusing moments, while others experience feelings of calm and beauty. According to Dr. Charlotte Martial, a neuroscientist with the Coma Science Group at the University of Liege, Tom’s experience stands out because of its gentle and positive nature.
Dr. Martial explained that most people report seeing a bright light or feeling as though they are watching their life flash before their eyes. Some experience fear or a sense of being trapped, while others find peace. But in Tom’s case, the experience was comforting, even though he was in a critical state.
This difference, she says, might be explained by how the brain reacts to the lack of oxygen and other changes that occur during a near-death event.
The Science Behind Near-Death Experiences
According to Dr. Martial, the science behind near-death experiences is both complex and fascinating. She and her team study what happens in the brain when a person approaches death, trying to understand how the mind produces such vivid sensations.
One key factor, she explains, is hypoxia, which means the brain is deprived of oxygen. When this happens, it triggers a chain of chemical reactions in the brain. These reactions can lead to hallucinations, feelings of floating, or a deep sense of peace.
“So we suggest that hypoxia may be the starting point of a cascade of specific neurochemical mechanisms,” Dr. Martial explained. In other words, when the brain senses danger or oxygen loss, it releases chemicals that may create powerful and unusual experiences.
Among these chemicals are neurotransmitters like serotonin, dopamine, noradrenaline, GABA, glutamate, and endorphins. Each plays a different role in shaping what a person might see or feel.
For example, serotonin and dopamine can produce visual effects or feelings of happiness. Endorphins, the body’s natural painkillers, can make someone feel calm even in moments of danger. This chemical mixture could explain why many people describe a sense of peace or lightness as they approach death.
Dr. Martial believes these near-death experiences may be a kind of defense mechanism created by the brain. When faced with extreme pain or fear, the body naturally tries to protect itself. The flood of calming chemicals might help ease suffering, allowing the person to face death without panic.
“This may arise as a protective mechanism when people face stressful or life-threatening situations,” she said. The brain might be trying to comfort the person, reducing their fear and pain even as the body begins to shut down.
This theory aligns with what many survivors say: that despite being close to death, they did not feel pain. Instead, they felt peace, light, or love. The mind, in its final moments, may give a gift of comfort to ease the transition.
Even with years of research, scientists still do not fully understand near-death experiences. The phenomenon blends biology, psychology, and spirituality in ways that are difficult to separate. Some researchers focus on the chemical processes in the brain, while others explore the possibility that consciousness might continue beyond physical life.
What makes near-death experiences so captivating is how real they feel to those who experience them. People like Tom Kearney are not just describing dreams or confusion. They describe entire worlds, clear conversations, and emotional reunions.
These stories challenge scientists to think about the nature of consciousness itself. How can a person with no brain activity still have such vivid experiences? Is the mind capable of existing beyond the body, or is it creating one final illusion to protect itself?
For those who have gone through a near-death experience, life rarely feels the same afterward. Many survivors say they lose their fear of death. They also become more spiritual or compassionate, valuing relationships and kindness more deeply.
Tom Kearney’s story shows how such an experience can reshape a person’s view of life. After recovering, he said he no longer worried about the small things. He focused instead on family, gratitude, and the strange beauty of being alive.
Scientists may continue to study the chemical and neurological side of near-death experiences, but for those who have lived through them, the meaning goes far beyond biology. Whether seen as a medical reaction or a glimpse into something greater, these moments remind us of how mysterious and powerful the human mind can be.
The study of near-death experiences continues to bridge the gap between science and spirituality. On one side, researchers like Dr. Martial look for measurable explanations. On the other hand, people like Tom offer deeply personal accounts that defy simple logic.
Perhaps the truth lies somewhere in between. The brain, in its final moments, may release a flood of chemicals that create feelings of peace and visions of loved ones. Yet those experiences still carry emotional and spiritual meaning that science alone cannot explain.
No matter what the cause, near-death experiences remind us of one thing: life is fragile and precious. The moments we have with others matter deeply, and understanding what happens at the edge of life might help us live more fully.
