The whole issue evolves around the the understanding of the brain. Although that might sound scientific, there is actually still room for religion and believes in this...
That the brain is extremely complex (actually way beyond what we could grasp... making it actually kind of a paradox

). We can understand how it works chemically and stuff, but we never can fully explain the ins and outs of it (yet). Like what is dreaming exactly (sure it are some chemicals things going on in the brain, and we can perfectly pinpoint where it occurs, but how does it work?).
If people report that they saw a tunnle of white light, are they liars because you don't believe there isn't something as a soul, life after dead, etc? No, those people really really really saw that. But it is a question of how they saw it. What were the chemical balances in their brain which produced such an image, and where does that image comes from? Culture and surroundings is only part of the explanation.
I for one, had a desease called epilepsy (the falling desease as it is sometimes unrightfully called) when I was younger (not in a severe form, so I was able to "grow out" of it). I have experienced many times very strange stuff right before I went uncounscience. And sometimes I did see myself lying on the floor and the people around me. The last time I went down I afterwads even could describe some stuff (in the room/people) which would be almost impossible to know without actually being consience and standing in the back. I even could recall some stuff people were saying which standed way back while I couldn't describe what other were saying who stood right beside me.
Does that mean there is something as a "floating soul" or whatever? I dunno. It sure means there are things going on which we still don't fully understand and the brain is way more powerfull and capable of doing things then we actually think or have prooven by now. Does it mean I believe in supernatural things like life after dead? not really. The question is also, is all this even "supernatural", it is quite possible that the brain records stuff in a very particular and maybe distored way when you are unconscience, so it could pick out sounds further away, while it couldn't 'focus' on stuff right behind it. The images could come from a very very deep memory, etc... The brain works totally different (inrational some might say) when your unconsience, and the most trouble here is, since the person is unconscience it is extremely hard to do research about this as you can't have scientific feedback.
Does that exclude religion and other stuff like that? Nope, since we don't understand the brain fully, we also still can't say something is scientific true or false or that there is something else out there.
In most cases, we say it is "supernatural" or "something out there" (or even "god" if you wish), for stuff we still connot explain fully in a scientific way or for things we don't know yet (eg: earth is flat issue). It doesn't mean it actually is "supernatural" and stuff (eg: mindreaders; are they truely "mindreaders" or are they people who can pick up and interpret body signals better than an average person.)...