A near-death experience was a sensation of detachment from one's body, the presence of a tunnel of light, the apparent viewing of one's own body from on high, and similar manifestations, experienced by people whose heart and brain would temporarily have ceased to function.
In 2373, Captain Kathryn Janeway started to wonder whether each of the near-death experiences they had heard about might be the result of an alien inhabitation. (VOY: "Coda")