Neuroscientist Christof Koch, president and chief scientist of the Allen Institute for Brain Science, wrote in an article for Scientific American: “I accept the reality of these intensely felt experiences. They are as authentic as any other subjective feeling or perception. “As a scientist, however, I operate under the hypothesis that all our thoughts, memories, precepts and experiences are an ineluctable consequence of the natural causal powers of our brain rather than of any supernatural ones.“That premise has served science and its handmaiden, technology, extremely well over the past few centuries.“Unless there is extraordinary, compelling, objective evidence to the contrary, I see no reason to abandon this assumption. “Modern death requires irreversible loss of brain function. When the brain is starved of blood flow (ischemia) and oxygen (anoxia), the patient faints in a fraction of a minute and his or her electroencephalogram, or EEG, becomes isoelectric—in other words, flat.“This implies that large-scale, spatially distributed electrical activity within the cortex, the outermost layer of the brain, has broken down. Recent books by Sam Parnia and Pim van Lommel, both physicians, describe studies published in peer-reviewed journals that attempt to pin down what happens during NDEs under controlled experimental conditions. Parnia and his colleagues published results from the latest such study, involving more than 2,000 cardiac-arrest patients, in October. And the recent books by Mary Neal and Eben Alexander recounting their own NDEs have lent the spiritual view of them a new outward respectability. Mary Neal was, a few years before her NDE, the director of spinal surgery at the University of Southern California (she is now in private practice). Eben Alexander is a neurosurgeon who taught and practiced at several prestigious hospitals and medical schools, including Brigham and Women’s and Harvard.It was Alexander who really upped the scientific stakes. He studied his own medical charts and came to the conclusion that he was in such a deep coma during his NDE, and his brain was so completely shut down, that the only way to explain what he felt and saw was that his soul had indeed detached from his body and gone on a trip to another world, and that angels, God, and the afterlife are all as real as can be.