Here is another link: https://www.statnews.com/2016/09/23/end-of-life-dying-willpower/ that is more (anecdotal) evidence. Biologically, there is nothing magical about consciously pushing your body to stay alive for a little while longer if the situation is not acute, but chronic. Same with consciously letting go. Release of adrenaline or other hormones triggered by intense emotions happens all the time, and I don’t see why end-of-life would be an exception.
Here is another link: https://www.statnews.com/2016/09/23/end-of-life-dying-willpower/ that is more (anecdotal) evidence. Biologically, there is nothing magical about consciously pushing your body to stay alive for a little while longer if the situation is not acute, but chronic. Same with consciously letting go. Release of adrenaline or other hormones triggered by intense emotions happens all the time, and I don’t see why end-of-life would be an exception.