Does our life really flash before our eyes when we die? Neuroscience may finally have clues to an answer.
Near-death experiences are a curious phenomenon shared by millions of people throughout history who nearly died but ultimately survived. Though the specifics differ, most of these folks recall experiencing a sense of serenity sweep over them when death was near. Frequently, they describe floating free of their bodies, or seeing their entire lives flash before their eyes, before returning to life. Imagine suddenly being outside your body, watching memorable events from your whole life flash by in a matter of seconds! That so many people report similar experiences suggests that our brains may all react in similar ways just before death.
However, investigating near-death experiences is extremely difficult because it’s nearly impossible to anticipate when someone will have one. For generations, neuroscientists have puzzled over what happens within the brain during these experiences, and after death. Yet, an accidental finding may have inadvertently shed some light in this area.
A new study published in the journal Frontiers in Aging Neuroscience suggests that the brain may remain active and coordinated during and even after death, and may even be wired to choreograph the entire process of dying. After an 87-year-old patient developed epilepsy, Dr. Raul Vicente of the University of Tartu in Estonia, and colleagues, employed continuous electroencephalography (EEG) to detect and treat seizures. Unexpectedly, the patient suffered a heart attack and died as these recordings were being made. This unforeseen incident enabled scientists for the first time ever to record the brain activity of a dying human being.
Dr. Ajmal Zemmar, a neurosurgeon at the University of Louisville, USA, who organized the study said: “We measured 900 seconds of brain activity around the time of death and set a specific focus to investigate what happened in the 30 seconds before and after the heart stopped beating.” “Just before and after the heart stopped working, we saw changes in a specific band of neural oscillations, so-called gamma oscillations, but also in others such as delta, theta, alpha, and beta oscillations.”
Brain oscillations (also known as ‘brain waves’) are rhythmic patterns of brain activity that occur naturally in living human brains. Various oscillations, including gamma waves, are connected with high-cognitive processes such as concentration, dreaming, meditation, memory retrieval, information processing, and conscious perception, just like those associated with memory flashbacks. “Through generating oscillations involved in memory retrieval, the brain may be playing a last recall of important life events just before we die, similar to the ones reported in near-death experiences,” Zemmar speculated. “These findings challenge our understanding of when exactly life ends and generate important subsequent questions, such as those related to the timing of organ donation.”
While this is the first study of its sort to monitor live brain activity in humans as they die, similar alterations in gamma oscillations have been seen in rats housed in controlled conditions. This implies that the brain may organize and execute a biological response that is conserved across species following death. These observations, on the other hand, are based on a single case and come from the brain of a patient who had suffered damage, convulsions, and edema, making the results more difficult to interpret.
Nonetheless, Zemmar intends to explore further cases and sees these findings as a source of hope. “As a neurosurgeon, I deal with loss at times. It is indescribably difficult to deliver the news of death to distraught family members,” he said. “Something we may learn from this research is: Although our loved ones have their eyes closed and are ready to leave us to rest, their brains may be replaying some of the nicest moments they experienced in their lives.”