Life flashes before our eyes when we die. We’ve seen it in the movies and we’ve read about it in the books, but until now we didn’t know for sure if it was a romanticized vision of death or if actually happens. However, a team of neuroscientists from the University of Tartu, in Estonia, confirmed that, indeed, life can flash before our eyes when we are about to die.
Our brain activates memories in the last moments
These neuroscientists were performing an electroencephalogram on an 87-year-old patient suffering from epilepsy to study his convulsions and readjust his treatment. However, during the test the patient suffered a heart attack and died, so that his last brain signals were recorded.
They measured exactly 900 seconds of brain activity around the time of death, so they could analyze what happened during the 30 seconds before and after the heart stopped beating.
They found that in the moments before and after the heart stopped working there were changes in two specific frequencies of neuronal oscillations, the so-called gamma and alpha waves. Alpha waves are known to be involved in cognitive processes as they inhibit networks that are irrelevant or disruptive, while gamma waves reflect patterns of brain activity linked to consciousness, expanded attentional focus, meditation, and recovery of memories.
Since cross-coupling between alpha and gamma activity is involved in cognitive processes and memory recall in healthy people, neuroscientists hypothesize that the brain might be replaying a last memory of major life events just before death, something similar to what has been reported by people who have lived near death experiences, who say that they have seen their life flash before their eyes.
In fact, although it is the first time that the activity of a human brain at the time of death has been recorded, these findings correspond to similar alterations in the neuronal activity of rodents, in which was observed an increase in the frequencies of low gamma band between 10 and 30 seconds after cardiac arrest.
These results, along with others, question the traditional view of the hypoactive brain during the phase close to death, since in reality it has been seen that electrical surges occur at the end of life. We don’t know why it happens, but it is one more step in understanding how we deal with those last moments of life.
Vicente, R. et. Al. (2022) Enhanced Interplay of Neuronal Coherence and Coupling in the Dying Human Brain. Front. Aging Neurosci; 10.3389.