Death is not so absolute, according to near-death experiences, because the brain continues to function after the heart stops. People who have experienced near-death experiences and come back to life frequently speak of an unexplainable condition of heightened awareness and consciousness that includes similar mental flashbacks and out-of-body experiences. The brain can continue to function after the heart stops for a longer period of time than was previously believed, proving that death is not as irreversible as was traditionally believed, even though science cannot yet explain how or why this happens.
The term “near-death experience” (or “NDE”) lacks a generally accepted scientific definition. As you might expect, it is fairly challenging to study them clinically, so most of what is known or assumed is dependent on people’s memories of their NDEs—the stories they tell later. People frequently talk about feeling at ease when they witness flashing lights or tunnels. They do, however, occasionally recall feeling afraid. Although it does not significantly enhance knowledge, a recent thorough assessment of studies on the subject by 18 doctors, neuroscientists, psychologists, and other experts presents a consensus view of what is known about what happens when we die and when someone is truly dead.
Sam Parnia, MD, director of critical care and resuscitation research at NYU Grossman School of Medicine and study team member, believes that death is not an absolute state. Instead, it’s a process that, in some people, may be able to be stopped after it has begun. Within minutes of oxygen deprivation, brain cells are not irrevocably destroyed when the heart stops. Instead, they ‘die’ slowly over many hours.
Separately, a recent case study with an 87-year-old man who was terminally ill is touted as the first time an electroencephalography (EEG) monitor was used to observe a dying brain. The researchers saw oscillations, or patterns of brain waves, in the 30 seconds before and after the man’s heart stopped. These oscillations are commonly associated with conscious perception, attention, memory retrieval, and dreaming.
The results are described in the journal Frontiers in Aging Neuroscience, where it should be noted that they are just suggestive because they concern a single person.
According to study team member Ajmal Zemmar, MD, a neurosurgeon at the University of Louisville, “Through creating oscillations involved in memory retrieval, the brain may be performing a last recall of crucial life events shortly before we die, similar to the ones recorded in near-death experiences.” These discoveries raise significant new problems, such as when to donate organs, and they put into doubt our conception of the precise point at which life ends.
According to Zemmar, a dying person’s brain may recall “some of the nicest experiences they experienced in their lives.”
However, 14% of the cases that were confirmed when yet another research team asked persons who said they had experienced near-death experiences about their encounters were unpleasant.
For individuals who are fortunate enough to come close to passing away, there does appear to be a silver lining to the whole experience: Whether life is wonderful or horrible, avoiding its end tends to make it better. According to Parnia and colleagues’ evaluation of the literature, those who have had near-death experiences frequently undergo “positive long-term psychological development and progress.”