Much of life remains mysterious to even the greatest scientific minds, but what happens at the point of death is also shrouded in mystery. As you’d expect, researching the effects of termination on a person is fraught with difficulties, both practical and ethical, but a new study, published in the Annals of Neurology, provides some fascinating insights into the neurobiology of dying.
Not only do animal and human brains perish in a similar fashion, but there’s a noticeable period wherein restoring brain function is, hypothetically, possible. This reminds us that the ultimate aim of such work isn’t merely to peer into the final moments of a person’s life, but to understand how to save them from death at the very last moment.
This pioneering, first-of-its-kind study, by scientists working at Charité – Berlin University of Medicine and the University of Cincinnati, assessed patients who had suffered from “devastating brain injury” through various means, including horrific traffic accidents, strokes, and cardiac arrests. This resulted in the activation of a Do Not Resuscitate-Comfort Care order, followed by the withdrawal of any mechanical breathing apparatus.
Much of what we know about brain death in this regard comes from earlier studies conducted on animals throughout the 20th century.
The brain is deprived of oxygen as the body’s cardiovascular system grinds to a halt. A condition known as cerebral ischemia kicks in, wherein the lack of necessary chemical components leads to “complete electrical inactivity” in the brain.
This so-called cerebral silencing is thought to occur in order for the starving neurons to conserve their energy – in vain, if death is knocking. All-important ions leak from brain cells, as supplies of adenosine triphosphate – the compound that stores and transports energy around the body – run low.
Tissue recovery becomes impossible. “Massive, irreversible injury of these cells develops within <10 minutes when circulation completely ceases,” the team explain in their paper.