When You Die You Have 7 Minutes of Brain Activity Left, Which Is Your Brain Playing Back Memories In A Dream Sequence
“My life flashed before my eyes” is a common expression used to describe the widely reported phenomenon of the life review, an event in which a person experiences a rapid and greatly detailed flashback of their life in chronological order. A life review is almost always triggered by a near-death experience, although at which stage during the experience the phenomenon occurs differs with each individual. Many are extremely affected by their near-death experiences as they often offer a new perspective on life; but as romantic and sentimental the thought, is there any actual authenticity to the rumour of the life review?
The cause of near-death experiences is unknown and opinions differ from person to person. Some have a more spiritualistic view and believe that the life review occurs when a person’s soul leaves their physical body and goes on to the afterlife. Scientists and psychologists, however, have searched for a more logical explanation, although even their ideas vary.
Many scientists believe that the life review is actually a hallucination caused by the process of the dying brain shutting down. Some think that the life review could be caused by euphoric endorphins being released or electrical discharges in the hippocampus (the brain area involved with memory); others say this brain activity is due to the brain being deprived of oxygen or glucose. One opinion is that the experience of seeing your life flash before your eyes might be caused by the stress hormone noradrenaline, which is released by the region of the brain that’s connected to the regions involved in mediating memory and emotion (such as the amygdala and hypothalamus).However, so far, science has yet to discover an irrefutable explanation.
It is true that the brain is capable of activity for some time after we die, as found by University of Michigan researchers. They performed a study into the after-effects of cardiac arrest on rats (due to the fact that approximately 20% of cardiac arrest survivors report experiences of some form of life review) and discovered high levels of activity. Many of the known electrical signatures of consciousness exceeded the levels found in the waking state, which supports the theory of the life review as it suggests that the brain is capable of organized activity during a near-death experience. However, this study was performed only on animals so as well as being unethical, it also can’t be definitively applied to human beings.
A 2010 study that looked at concentration of CO2 in the blood shortly after cardiac arrest offers another explanation into life reviews. Many studies have linked high levels of CO2 in the bloodstream with hallucinations and in this study, published in the journal Clinical Care, 11 patients who reported experiencing near-death experiences tended to have significantly higher levels of CO2 in their bloodstreams. But again, this study’s findings cannot be taken as fact as not every patient in the study who had high CO2 levels experienced a life review.
So instead near-death experiences could be caused by a person’s mind, and not the physiological processes they go through in death. Deeply religious people are more likely to report life reviews when dying, especially compared to those who were afraid of dying. This shows that the life review may be all psychological and based on your attitudes to death at the time, but what do you think?
Are you on the side of biology or psychology? Have you ever had a near-death experience and, if so, what’s your personal view on them?