What do we see when we die? The activity of the dying brain provides some clues.

For the first time, scientists have managed to capture the brain wave activity of a person at the moment of death, bringing us closer to an answer to the eternal question: what do we see when we die?

An 87-year-old man, after a fall, was taken to the emergency room and died of a heart attack while connected to an EEG machine that was recording his brain waves. This is not the first case of brain activity being recorded in death, but it is the first time that detailed data has been captured about this moment.

Dr. Sam Parnia of NYU Langone University explains: "For decades, people have reported episodes of strange or heightened awareness during near-death experiences. Until now, they have been viewed as mere personal anecdotes, but surveys suggest that this experience occurs in about 10% of people, over 800 million people."

The researchers captured about 900 seconds of brain activity and specifically analyzed the 30 seconds before and after the heart stopped. After cardiac arrest, a change was observed in brain waves associated with higher cognitive functions such as concentration, memory recall and conscious perception, a possible indicator of memories coming back to life.

The findings were published in Frontiers in Aging Neuroscience in February 2022. The researchers suggest that this may be an indicator of "mental clarity" at the end of life, an experience that occurs just as the brain is shutting down.

But there are also uncertainties. The patient had brain damage, including bleeding and seizures, and was taking anti-seizure medication, making it difficult to accurately interpret the data.

However, by analyzing the relationship between alpha and gamma waves, known for memory recall, the researchers suspect that the patient may have experienced what is often described as "life flashing before our eyes." Alpha waves are associated with states of calm and learning, while gamma waves, the faster ones, are associated with awareness, memory, and focus.

Another study from the University of Michigan in May 2023 found increased gamma wave activity in two comatose patients who died after cardiac arrest. The activity occurred in a "hot spot" of the brain associated with dreams and altered states of consciousness.

"While the full meaning of these findings is still lacking, they indicate that the brain remains active after death," the authors write. This supports the idea of ​​a "hidden consciousness" that could explain near-death experiences.

According to Dr. Parnias, when the brain is shutting down, some parts of it are freed from the inhibitions that normal brain function usually imposes, opening access to deeper levels of consciousness.

However, true brain imaging remains nearly impossible, as observing healthy individuals on the verge of death is unethical and practically unaffordable. These rare findings are the result of chance and emergency hospital conditions.

To better understand what happens in the brain during death, researchers say more ICU patients who survive cardiac arrest need to be included so they can report what they experienced after the increased brain activity. / Popular Mechanics