【脳の不思議】自分は死んでいるかもしれないという奇妙な症状

The strange, rare medical condition that leads people to insist they don’t actually exist

　Cotard’s Syndrome—in which a person can believe that they’re dead, that their organs are rotting, or that they don’t exist—was first identified by the French neurologist Jules Cotard more than a century ago, in 1882. But the condition is so rare that it’s still far from fully understood.

　Though it’s undeniably horrific for those experiencing it, Cotard’s Syndrome presents a fascinating conundrum for those studying the disorder. The condition’s central contradiction—how can someone articulate the thought that they don’t exist?—raises questions and potential answers about how human self-awareness works.

　A 2013 case study of a Cotard’s sufferer showed low activity in the brain network associated with awareness of the body. It’s only one example (as with much of Cotard’s Syndrome research, because the condition is so rare), but unpacking how the brains of those with the syndrome offers hints as to how normally-functioning brains develop a sense of existence.

　But Cotard’s Syndrome isn’t simply interesting from a neuroscience or psychological perspective. In the world of artificial intelligence, roboticists are working to build ever-more complex machines that replicate human behavior. One of the central questions is whether machines can truly become self-aware. Could understanding Cotard’s Syndrome provide the answer?

QUARTZ

Cotard delusion

　Cotard delusion is a rare mental illness in which the affected person holds the delusional belief that he or she is already dead, does not exist, is putrefying, or has lost his or her blood or internal organs.

Wikipedia