- A recording of a man’s brainwaves at the time of his death showed patterns similar to what occurs during dreaming, memory recall, and meditation.
- Around the time of death, the EEG recorded changes in gamma brainwaves (oscillations) and other types of brainwaves.
- The man was in the hospital after developing epilepsy after a fall. During an EEG scan, he had a heart attack and died.
A team of scientists inadvertently recorded the brainwaves of an 87-year-old patient as he died, providing the first glimpse at what happens in the brain during the final moments of life.
The man’s brainwave patterns in the 30 seconds before and after his heart stopped beating were similar to what occurs during dreaming, memory recall, and meditation.
The man was in the hospital after developing epilepsy after a fall. While doctors were using continuous electroencephalography (EEG) to detect his seizures and treat him, the man had a heart attack and died.
Around the time of death, the EEG recorded changes in gamma brainwaves (oscillations) and other types of brainwaves.
“Through generating oscillations involved in memory retrieval, the brain may be playing a last recall of important life events just before we die, similar to the ones reported in near-death experiences,” study author Dr. Ajmal Zemmar, a neurosurgeon at the University of Louisville in Kentucky, speculated in a news release.
However, it’s impossible to know based on the EEG what the man may have experienced in his mind at the time of death.
In addition, “These findings challenge our understanding of when exactly life ends and generate important subsequent questions, such as those related to the timing of organ donation,” said Zemmar.
The researchers caution against drawing broad conclusions based on this study, which involved only one patient.
In addition, the man had epilepsy with swelling and bleeding in the brain. “Traumatic brain injury (TBI) and white matter damage can influence rhythmic brain activity,” the authors wrote in the paper.
The study was published Feb. 22 in the journal Frontiers in Aging Neuroscience.
In a 2009 study, researchers from George Washington University made EEG recordings on seven patients who were critically ill, at their time of death.
They found an increase in electrical activity in the brain that occurred even when there was no detectable blood pressure.
“Patients who suffer ‘near death’ experiences may be recalling the aggregate memory of the synaptic activity associated with this terminal but potentially reversible hypoxemia [lack of oxygen],” they speculated in the paper.
In a 2013 study, another group of researchers saw similar changes in gamma brainwaves in rats at the time of death, as occurred in the most recent study.
Within the first 30 seconds after the heart stopped beating, all of the rats displayed a widespread surge of synchronized brain activity associated with a highly aroused brain, they reported.
“We were surprised by the high levels of activity,” study author Dr. George Mashour, assistant professor of anesthesiology and neurosurgery at the University of Michigan, said in a news release at the time.
“In fact, at near-death, many known electrical signatures of consciousness exceeded levels found in the waking state, suggesting that the brain is capable of well-organized electrical activity during the early stage of clinical death.”
The similarity between the results of the two studies suggests that there may be a common neurological response to death that occurs across species, at least among mammals.
Zemmar said in the release that he plans to investigate similar cases.
“As a neurosurgeon, I deal with loss at times,” he said. “It is indescribably difficult to deliver the news of death to distraught family members.”
“Something we may learn from this research is that although our loved ones have their eyes closed and are ready to leave us to rest, their brains may be replaying some of the nicest moments they experienced in their lives.”