When dying, the brain bursts out supernormal electrical signals. Is the binary concept of life and death outdated?

This article comes from the WeChat public account:SF Chinese (ID: kexuejiaodian)Author: SF

The latest research shows that after the heartbeat stops, the brain will not die immediately, on the contrary, there will be explosive conscious activities.

By | Sara Reardon

Editor | Jiayu Liu

Many people who have been brought back from the dead have described feeling out of their bodies. Their experiences are very similar, such as a lifetime of experiences flashing before your eyes, unforgettable moments reliving in your mind, out-of-body experiences, feeling that you are watching yourself outside your body, and so on.

Recently, a small study mapped the brain activity of four volunteers at the end of their lives. It turned out that after their hearts stopped beating, there was a burst of brain activity.

The binary concept of life and death is outdated

In May 2023, a study published in the “Proceedings of the National Academy of Sciences” may explain why images of experiences in this life suddenly flash back to my mind after my heart stops beating. “This phenomenon suggests that the brain is recognizing signs of conscious awareness,” said pulmonologist Sam Parnia of New York University Langone Medical Center.

Although medical science has always defined death as the irreversible cessation of the heart,Brain activity in many animals and humans can persist for seconds or even hours after the heart stops beating, recent research shows. In 2013, for example, neuroscientist Jimo Borjigin’s team at the University of Michigan found that the brains of mice showed signs of consciousness up to 30 seconds after their hearts stopped beating. “The binary notion of life and death is outdated,” Parnia said.

abnormal EEG signal

“Despite hundreds of years of extensive research on clinical death or near-death, we know next to nothing about brain activity during the dying process,” Borzigin said. In her research, she and After the team reviewed the medical records of four volunteers who were in a coma and kept vital signs on life support, doctors put the EEG caps on the volunteers.

The EEG cap continuously monitored EEG signals in each volunteer’s brain. During the monitoring, the brains of two volunteers were suddenly illuminated by a high-frequency pattern of neuronal activity in gamma waves, and 2 seconds later their hearts stopped beating, and this high-frequency pattern continued after the heart stopped continued. At the same time, related studies have found that when a healthy person is actively recalling past events, learning or dreaming, the same EEG pattern will also appear. Neuroscientists believe that the activity of this EEG signal is closely related to consciousness.

Ajmal Zemmar, a neurosurgeon at the University of Louisville in the US, says gamma waves may indicate that different brain regions are working together to combine different senses into awareness of objects. For example, combining sight, smell, and hearing. Through the synergy of these senses, we quickly perceive and build a picture of everything around us in our brain. “How the brain does this is one of the biggest mysteries in neuroscience,” Zemora said. But monitoring the same gamma waves in dying people suggests that the brain recalls unforgettable memories during the dying moments. biological mechanism. Zemora’s lab had previously detected similar gamma waves in a patient who died of a heart attack while his brain was being monitored for seizures.

Brain bursts during near-death or a protective mechanism?

“This study is very important for the field of near-death experiences and for the field of consciousness more generally,” says Charlotte Martial, a biomedical scientist at the University of Liege in Belgium who studies near-death experiences. But not all near-death experiences. While dead survivors all had flashbacks to lifetime experiences or out-of-body experiences, only two of the four volunteers in the Borzigin study showed gamma activity. Borzikin pointed out that the two volunteers had a history of epilepsy, which she believes may have abnormal rhythms in their brains.

Borzigin’s team also found a significant increase in electrical activity in the brain’s temporal-parietal-occipital junction, an area associated with consciousness that is activated during dreams, seizures and near-death experiences. She sees the bursts of brain activity as a survival protection mechanism, a mode that goes into the brain once it’s starved of oxygen. Studies of animals that have experienced brain death have found that when dying, the brain shuts down external signs of consciousness, releasing a flood of signaling molecules and producing unusual brain wave patterns in an attempt to revive.

Borzikin hopes to test her findings by collaborating with other medical centers to study the brain activity of dying patients. Finding answers to how the dying process happens is crucial, Zemora said. Through this research, we can unravel the mysteries of death and gain a better understanding of the brain. It is a step closer to uncovering the mysteries of the human body and life, aging, sickness and death.

references:

• https://www.science.org/content/article/burst-brain-activity-during-dying-could-explain-life-passing-your-eyes