When white blood cells die, they release signals to neighboring leukocytes. But what happens to us when we die?
Animal studies conducted over 10 years ago revealed high electrical activity in the brain after their clinical death.
The study’s lead author, Jimo Borjigin, described her study to be the first dealing with what happens to the neurophysiological state of the dying brain.
“It will form the foundation for future human studies investigating mental experiences occurring in the dying brain, including seeing light during cardiac arrest,” the professor of neurology at the University of Michigan said.
It was in 2022 when a study offering better insights into the aftermath of death was published. Researchers in the US performed an electroencephalogram (EEG) on an 87-year-old man as he passed away. The elderly man suffered from epilepsy. They were able to record the patient’s brain waves 15 minutes after he died from a heart attack.
When the researchers looked at the brain waves, they noticed an increase in ‘gamma oscillations.’ These oscillations control the connectivity between various regions in the brain, making them important for perception, memory, and emotion.
“We report what is, to our knowledge, the first continuous EEG recording from the human brain in the transition phase to death. We find decreased THETA activity and an increase of absolute gamma power after bilateral suppression of neuronal activity,” the researchers wrote in the study.
Patient One
In 2014, a 24-year-old woman, pregnant with her third child, was named Patient One when she was taken off life support. According to The Guardian, Patient One would become one of the most intriguing scientific subjects in recent history.
There are many cases of near-death experiences. New technologies are helping doctors and researchers to find out more about them. “I believe what we found is only the tip of a vast iceberg,” Borjigin told The Guardian. “What’s still beneath the surface is a full account of how dying actually takes place. Because there’s something happening in there, in the brain, that makes no sense.”
Charlotte Martial, a neuroscientist at the University of Liege in Belgium, told The Guardian that we are in a crucial moment where we have to disentangle consciousness from responsiveness and maybe question every state that we consider unconscious.
Borjigin hopes that understanding the neurophysiology of death can help us to reverse it. She already has brain activity data from dozens of deceased patients that she is waiting to analyze.
The dying brain
A study published in 2023 provides early evidence of a surge of activity correlated with consciousness in the dying brain. The scientists identified four patients who passed away due to cardiac arrest in the hospital while under EEG monitoring. Two of the patients showed an increase in heart rate and a surge of gamma wave activity— recognized as the fastest brain activity and associated with consciousness.
Because of a small sample size, the authors caution against making any global statements about the implications of the findings. They also note that it’s impossible to know, in their study, what the patients experienced because they did not survive.
“We are unable to make correlations of the observed neural signatures of consciousness with a corresponding experience in the same patients in this study. However, the observed findings are definitely exciting and provide a new framework for our understanding of covert consciousness in the dying humans,” she added in a statement.
