What is the Difference Between a Coma and Brain Death?

What do people who have near-death experiences actually see at that moment? Many see a scene like seeing a bright light at the end of a narrow tunnel; Again the faces of their loved ones floated before the eyes of many; Many feel as if they are floating in the void.

In a recent study, scientists discovered waves that create 'consciousness' in the human brain during the process of death.

"It's a neuroscientific paradox how a dead brain can emit waves similar to those of a living person during the process of death," said Jimo Borzigin of the University of Michigan, who led the study.

The study reviewed EEG reports of four patients during the dying process. All four patients died in hospital.

Besides, all four were in coma before their death, they were not showing any normal reaction. Life support was withdrawn with the consent of each patient's family, and all subsequently died of cardiac arrest.

Scientists in the study analyzed EEG data from four patients from the time they were taken off life support until they died.

The study found that two patients' heart rates increased after life support was withdrawn; As well as increased gamma wave fluctuations in their brains. Gamma wave fluctuations are analyzed to monitor the brain's fastest activity. This wave is basically related to human consciousness.

However, the study, published in the Proceedings of the National Academy of Sciences, showed no such results in heart rate or brain activity in two other patients.

According to lead researcher Borzigin, the new findings may be related to patients becoming 'intrinsically awake'.

"The increase in gamma waves during death may activate a hidden consciousness within, or resurface a memory from the past, or it may be a survival mechanism of the brain; we don't know for sure yet," he said.

Before this, another group of researchers based in Vancouver, Canada, recorded how the brain waves of people work before death.

A group of scientists measured the brain waves of an 87-year-old man with epilepsy. But he died of sudden cardiac arrest during the neurological recording, along with a strange discovery.

The recording shows that the old man's brain recalled various memories of his life 30 seconds before and after his death.

In a study published in 'Frontiers in Aging Neuroscience' last Tuesday, the researchers termed such brain activity as the 'ultimate memory' of life.

Dr. co-author of the study. Ajmal Jemar said at that time that 30 seconds before the death of the old man, the blood supply from the heart to the brain stopped. The old man's brainwaves followed the same pattern as our brains when concentrating, dreaming or reminiscing. The condition continued for 30 seconds after the patient's heart stopped beating and at one point he was pronounced dead.

The research of the scientists gives birth to another new question, that is - when does the death of people actually happen? When the heart stops beating? Or when the brain stops working?

However, at that time, the researchers did not give any final decision on this matter.

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