I nominate
Passage
by Connie Willis
“One of those rare, unforgettable novels that are as chilling as they are insightful, as thought-provoking as they are terrifying, award-winning author Connie Willis's Passage is an astonishing blend of relentless suspense and cutting-edge science unlike anything you've ever read before.
It is the electrifying story of a psychologist who has devoted her life to tracking death. But when she volunteers for a research project that simulates the near-death experience, she will either solve life's greatest mystery -- or fall victim to its greatest terror. “
https://smile.amazon.com/Passage-Nov.../dp/B0030P1WSQ
https://www.kobo.com/us/en/search?query=connie%20willis
Also available at some Overdrive Libraries