Your Brain at the Moment of Death
Resuscitation expert Sam Parnia studies near death experiences—and how your brain can give you access to new dimensions of reality.
There is a fierce and political debate in this country about when human life begins. Some anti-abortion advocates say human life starts at conception, while others say it is when a heartbeat can be detected.
In contrast, there is little to no debate about when life ends. In its Uniform Declaration of Death Act (1980), the Society for Post-Acute and Long-Term Care Medicine says “death has occurred when an individual has sustained either irreversible cessation of circulatory and respiratory function or irreversible cessation of all function of the entire brain including the brain stem.”
Such a choked, clinical description makes death seem thin when compared to the narrative richness of religious poetry through the centuries—from Buddhist visions of ongoing reincarnation to the proverbial meeting with St. Peter at the pearly gates. Clinical language also falls short of the everyday experience of the millions of people who have opened that door and survived—later to recall their encounter with death through unexplained lucid episodes of heightened awareness—that mythical light at the end of the tunnel.
“These have been reported using the popular—yet scientifically ill-defined—term near-death experiences,” says Sam Parnia, the director of critical care and resuscitation research at New York University’s Grossman School of Medicine. Despite being the domain of speculation by philosophers and poets since the dawn of time, death has never been the subject of rigorous scientific study—until now. More and more clinicians are now recording near-death experiences.
Over the past two decades, Dr. Parnia has led pioneering research into the recalled experiences of death, particularly among survivors of cardiac arrest. The AWARE (AWAreness during REsuscitation) studies from his lab examined the experiences of hundreds of patients with cardiac arrest who had biologically crossed over the threshold of death before being resuscitated. Many of the survivors report seeing deceased relatives and reviewing their actions and intentions toward others throughout their lives, and afterward, many recalled details of their resuscitation.
We sat down recently with Parnia to better understand what happens as we near that inevitable moment at the end of all our lives.
proto.life: What happens in our brain as we die?
PARNIA: As the heart stops and we die, the brain is flatlined and nonfunctional. However, using brain electrical monitoring, there is growing evidence that in this state (as people pass away), there are markers of activity (beta, delta, and sometimes gamma waves) that emerge for a very short period. These are ordinarily found when people are having conscious experiences, but now they are also seen to emerge at the time of death, when the rest of the brain has a background of being flat.
What is the significance of these markers?
It is possible that these are the underlying markers of the lucid conscious experience that millions of people have reported at the time of death. This includes the experience of being able to recall every minute detail in their lives and to evaluate the quality of their actions, intentions, and thoughts towards others. This is intriguing, as people experience so much more detail in that state of death than they can ordinarily—while not in a state of death.
As people die and the parts of the brain that are ordinarily active during our day to day lives are no longer required and shut down, they enable the disinhibition of areas in the brain that are otherwise ordinarily not active and are inhibited in day-to-day life. This is what we are seeing with the emergence of those brain markers at the time of death. This disinhibition of these areas then seems to give people access to dimensions of reality that they would ordinarily not have access to in day-to-day life. This may be important from an evolutionary perspective, as they may not be needed until we reach death.
So, in short, it is not so much that the brain is creating these experiences as a hallucination or illusion but rather than the brain is enabling access to aspects of reality and a person’s own consciousness, including the totality of a person’s conscious experiences throughout the entirety of their lives, real and correct memories of their own interactions with others in life and the meaning of those actions, thoughts, and intentions.
For the first time in history, science is exploring death itself and what happens after death.
How much of religion and visions of pearly gates can be correlated or even traced to a biological process?
As regards religion and even philosophy—of course, this is complex. Clearly throughout time and in every civilization, there have been some individuals who have proclaimed that our lives, actions, thoughts, and even intentions towards others are not meaningless and that we are not annihilated with death. Now for the first time in history, science is exploring death itself and what happens after death. What these experiences do provide is support for that line of thought. However, they do not support much of what else is associated with religion. For instance, people do not experience [exactly] what their religions had taught them, and atheists and agnostics also experience the same review of their lives and lucidity with death. So, in short, this experience and what science is discovering at the time of death seems to transcend any specific religious doctrine. These experiences also do not support much of the rest of what is associated with religion—i.e., specific rituals, sociocultural aspects, and so on.
What about the tunnel of white light?
People report seeing a luminous, kind, and perfect entity that is perceived as a light because it is so luminous. It is not some random white light like we see when looking at a light. However, none of the aspects of the experience of death, whether the experience of a personified luminous entity or [a] perception of travel back home (the perception of a tunnel) are representative of the human experience of death.
Parnia is not the only researcher looking into what happens when the brain dies. In February 2022, a multi-country research team published a study in the Frontiers of Aging Neuroscience, which told the case history of a man who had a cardiac arrest while undergoing a brain scan. The brain signals recorded just before and after the heart stopped were similar to those that people experience when recalling memories and those recorded at the point of death in rats. And researchers at the University of Chicago published a study that found gene expression in some cells actually increased after death.
In May, Parnia led a multidisciplinary team of national and international leaders who published the first peer-reviewed consensus guidelines for the scientific study of recalled death experiences. The published guidelines end with this statement: “Although systematic studies have not been able to absolutely prove the reality or meaning of patients’ experiences and claims of awareness in relation to death, it has been impossible to disclaim them either.”