What Happens In The Brain Before Death?

An American study now reveals that at the moment of death, our brains allow memories to surface. At least this is what the brain waves of a patient at the moment of his death suggest.

The fact that this brain activity was recorded is due to a coincidence. An 87-year-old patient, who had undergone head surgery after a fall and suffered from epileptic seizures, was being monitored by electroencephalography (EEG). During one of these recordings, which records the electrical activity of the brain, the patient suffered a heart attack and died.

According to the report in the journal Frontiers in Aging Neuroscience, 15 minutes of brain activity was recorded while the patient was dying. “We focused on what happened in the 30 seconds before and after the heart attack,” explained the study’s director, Ajmal Zemmar, a neurosurgeon at the University of Louisville in the United States.

“Just before and after the heart stopped beating, we observed changes in a specific range of frequencies of neuronal oscillations, also called gamma oscillations, but also in others such as delta, zeta, alpha, and beta oscillations,” the specialist said.

These brain waves trace patterns of rhythmic neural activity. Different waves are associated with different functions, and the frequency patterns described in the study are similar to those produced when meditating or remembering. This suggests, Zemmar speculates, that shortly before death the brain may be replaying through these oscillations final memories of important life events, “similar to near-death experiences.”

Frank Erbguth, medical director of the University Clinic for Neurology in Nuremberg, Germany, is not surprised by the observations: “It is nothing new that the human brain creates its image worlds in certain situations.” He continues, that this is known from people who suffer from migraines or drug users, among others. “Near-death experiences are therefore part of a very diverse series of phenomena in which the brain produces images,” says the president of the German Brain Foundation.

According to Erbguth, there is an explanation for what happens in the brain, and he points out that at the moment of death, the carbon dioxide content in the cells increases: “This causes a change in the brain’s electrical system and the brain’s metabolism; near-death experiences are located in these two keyboards.”

Erbguth adds that these experiences can also occur in people who are particularly good at meditation and that in these individuals, electroencephalograms showed an increase in gamma spectra, similar to those recorded in the study: “And we know that these gamma activities indicate a recovery of memories,” he asserts.

Gamma waves, on the other hand, are very fast, oscillating at a speed of 30 hertz per minute. “In a conventional electroencephalogram, the gamma band is not visible,” the neurologist pointed out, adding that the differentiated evaluation of the wave ranges carried out in the study is, therefore, a new aspect.

Another study showed similar results already in 2013, except that these changes in gamma waves occurred in rats. The authors of the current study interpret this as a possibility that, upon death, a biological reaction takes place in the brain that could be the same in all species.

However, Erbguth objects, that this study was based on a single patient whose brain was injured and who had also suffered epileptic seizures: “This epileptic activity means that the brain’s electricity is altered,” so, according to the academic, it is difficult to conclude the normal dying brain.

However, the neurologist admits that the study adds another facet to the already extensive knowledge about the dying brain: if blood circulation stops, nerve cells stop communicating with each other, certain rhythms of the brain’s electrical system shift and the cells send a final electrical message.

The fact that this occurs in the form of a shock wave was described by German and American neurologists in the journal “Annals of Neurology” as early as 2018. Erbguth explains the attention such studies usually receive by saying that they promise to take a look behind the curtain of death: “But everything we look at takes place in front of the curtain,” he adds, noting that even people with near-death experiences have only come close to it and not gone beyond it.

But for neurosurgeon Zemmar, the current study holds out hope for loved ones: “What we can learn from this research is that even when our loved ones have closed their eyes and are ready to rest, their brains may be replaying some of the most beautiful moments they have ever experienced,” he says.

Neurologist Erbguth is more moderate in his opinion: “Our brain is indeed capable of producing images again,” he says, adding that the accounts of people who have had near-death experiences demonstrate this and that it is legitimate to assume that the brain also has this capacity when it is dying.

However, he notes, resuscitation medicine studies have shown that while two-thirds of people with a near-death experience saw pleasant images, one-third reported very unpleasant scenes. “I would like the transition to death to be accompanied by pleasant experiences, but I am afraid that this is not in our hands,” Erbguth concludes.