I've never had a near-death experience so I cannot tell you, but I can tell you I have a vivid pre-life memory. I can describe in details the front of the building where my parents got married, despise the fact I've never been there (physically) not even when a baby, never heard anyone talking about it, and nobody has pictures of it. I described it to my mother when I was around 6 to 8 yo and I still remember it. I remember the street, the details on the windows, ground, door, the steps and so on. It was completely devoid of people and I remember being there with someone who's completely blurry in my memory, the visual memory is also from a higher angle, around 7' above the ground which is a bit higher than my current height.
I have some theories for that. It was a strange coincidence (which I doubt due to the amount of precise details, but I don't discard it). It could be some weird psychic event, like I captured the image from someone else. Someone described it when I was a baby and I created it in my head (my parents don't remember anyone even talking about it after I was born, specially since we moved right after that and there was no contact with anyone who had been there for years). There's perhaps a bit of genetic memory somehow (which I doubt more than the others), or there's more to being than just being alive.
Personally, I wouldn't discard any of the possibilities. But it's my memory and I lean towards it being a valid memory.