Anil Seth: A new study suggests such phenomena are caused by a surge of brain activity – and shows death is a process, not an event.
We have all wondered what it will be like to die, and what – if anything – might happen afterwards. The prospect of no longer existing seems so difficult to accept that cultures throughout history have developed spiritual and religious beliefs about the persistence of consciousness after the body's physical demise. Back in the 17th century, René Descartes famously proposed that "mind stuff" (res cogitans) has a separate form of existence from "material stuff" (res extensa), thus introducing the thorny problem of how they might interact, and whether one might exist without the other.
Beliefs about persisting consciousness have been reinforced by reports of unusual "near-death experiences", which often involve the feeling that the soul has left the body and is approaching another reality characterised by bright light and blissful feelings. Now neuroscience has got in on the act, with a remarkable study by Jimo Borjigin and colleagues from the University of Michigan showing a transient surge in brain activity after the heart stops.