Near-Death Experiences

I can see many ways to aproach this question. on the physical sense, as if its a halucination, many say that when we die our brain produces a bunch of dMT and what we experience is basically one of the strongest halucinogens that exist and if its anything like recreational use of DMT, which I've done a few times, it can induce what I call "eureka experience" which is the illusion of thinking you suddenly understand the meaning of life. but if you write it down and read it the next day it can sometimes be mostly non-sense. the eurika experience is a sensation that feels like information. that "now I understand" sensation but without rationality. just like how non-sense in dreams seem like just normal when you're in it.
another way to look at it, lets say " spiritual" way, is that some say we are eternal beings and we come to earth to experience new things but to make the experience really intense and meaningful we intentionally leave our knowledge behind in the same way as to trully experience a movie you have to forget that its a movie, if you watch the movie and see actors and special effects you will not experience it the way it was meant to be experienced.
on a more personal note I almost drowned once and just when I gave up and accepted I was going to die I had the sensation of a window of light apearing and telling that if I die its going to be ok because they will take care of me.
to come back to the DMT experience, its a very common effect that people meet "teachers" that tell them about important life lessons or big theories about the meaning of life. during such an experience a teacher, wheather a halucination or not, told me some important stuff about life and ended with " but now the lesson is over and you have to go " and just like that I was back and completely lucid and normal but feeling happy and at peace.
note: I am in no way suggesting that someone should try this, it could warp your mind forever.