It is often assumed that when humans die their brains cease to function. Near death experiences, on the other hand, are widespread around the world. Some cardiac arrest survivors from various cultural and religious backgrounds have experienced near-death experiences, which may involve a sense of leaving the body, a light at the end of a tunnel, or recollections of previous occurrences.
Scientists are now making progress towards a scientific explanation of these brain activity or these occurrences.
Few Facts from the Research
In a study published in the Proceedings of the National Academy of Sciences, researchers report that two of four comatose dying patients experienced a surge in brain activity that resembles consciousness after they were taken off ventilators and their hearts had stopped.
The findings suggest that scientists still have a lot to learn about how the brain operates when we die. The finding “suggests we are identifying a marker of lucid consciousness,” says Sam Parnia, a pulmonologist at New York University who did not participate in the study.
Scientists don’t know why people have near-death experiences. According to the report, these inexplicable behaviours “represent a biological paradox that challenges our fundamental understanding of the dying brain, which is widely believed to be non functioning under such conditions.”
Previous research, however, has demonstrated higher brain activity near the end of life. Jimo Borjigin, a co-researcher of the current study and a neuroscientist at the University of Michigan, discovered in a 2013 study of rats that their brains produced surges of gamma waves for 30 seconds after their hearts stopped.
Gamma waves are rapid brain waves related with attention, working memory, and long-term memory, thus they suggest, but do not prove, that the rats were conscious, explains Stephanie Pappas of Live Science. Furthermore, a 2022 study discovered that a person who died of a heart attack while having their brain activity recorded exhibited gamma wave activity after cardiac arrest.
The new study looked at four individuals who died while having their brain activity recorded using electroencephalography (EEG). According to Hannah Devlin of the Guardian, all were unconscious and regarded beyond medical help. Their families authorised physicians to remove the patients from life support.
However, after being taken off life support and experiencing cardiac arrest, two of the patients’ brain activity assessments revealed increases in gamma waves. The surges lasted a few minutes and were occasionally quite powerful.
“It was crazy high,” Borjigin says Clare Wilson of New Scientist.
Notably, researchers saw high signals in a region of the brain that can be active during out-of-body experiences or dreams. “If this part of the brain lights up, it means the patient is seeing something, hearing something, and possibly feeling sensations outside of the body,” Borjigin told Agence France-Presse (AFP)’s Issam Ahmed.
According to the scientists, the findings might lead to more research into the dying brain and awareness after cardiac arrest.
“This paper is really important for the field and the consciousness field more generally,” Charlotte Martial, a biomedical scientist at the University of Liège in Belgium who studies near-death experiences but did not participate in the study, tells Science.
Plans for Future Investigations
According to Vice’s Becky Ferreira, Borjigin plans to collect more data about dying brains in the future. The activation of gamma waves “needs to be confirmed in more patients,” she tells the journal.
“The more consistent findings we have, the more evidence there is that this is likely a mechanism happening at the time of death,” Ajmal Zemmar, a neurosurgeon at the University of Louisville Health and co-author of the 2022 research, told Live Science. “It would be even better if we could narrow this down to a single location.”