How early religious beliefs about the afterlife may have been formed

I was listening to a Skeptiko podcast where Alex Tsakiris talks to Dr. Eben Alexander, a neurosurgeon who had a near-death experience (NDE), and I began to wonder what the first person to have a NDE may have experienced.  Could that be how people first learned of an afterlife?  Could this be how the earliest religions began?

Each person who has a NDE has a unique experience.  But many commonalities have been noted.  People often report being aware of being outside of their body and may be able to remember hearing doctors or nurses saying specific things or just floating around and being able to see things that they wouldn't be able to see from the position of their physical body.  They also often report seeing loved ones that have already passed on and possibly religious figures such as Jesus or some other divine beings like angels.  Traveling through a tunnel towards light is common factor as well as having a life review.  But despite commonalities, each experience is unique.  Sometimes cultural differences may even be a factor.

But differences shouldn't be surprising.  In life, we all have unique experiences everyday.  Our consciousness may be confined to our physical self, but we still have free will and make our own decisions.    We also have our own opinions and interpretations.  Our day to day lives may have their similarities, such as brushing teeth, going to work, having lunch, watching TV, etc.  But despite similarities, there are still differences.  We don't all use the same toothpaste.  We don't all have the same job or drive the same kind of car to work.  We don't necessarily like exactly the same foods or TV shows.  If you lived in a third world tribal society, you probably wouldn't being using toothpaste or watching any TV at all...but you'd still get up in the morning and you'd still want something to eat.  So if our day to day lives are unique with some similarities, why should it be surprising that the afterlife would be unique with some similarities?

But anyways, the question here is, could a NDE have been the origin of any number of ancient and possibly prehistoric religions?  Although many of the reports of NDEs come from people who have been revived on an operating table, there are instances where people have been mistakenly thought to be dead when they really weren't, and, in times past, there are even reports of people being mistakenly buried alive (you can see a Snopes article on that subject here).  So if people have been mistakenly thought to be dead in time's past, then it may also be possible that they may have experienced a NDE.  If so, then the story they may have told about their experience may have formed an ancient religion...especially if the stories were being told by someone everyone else had thought to be dead.

Of course, it's also entirely possible that some religious beliefs were formed by drug induced hallucinations or outright fabrications, but what if there is something more to it?  What if some beliefs began from a real experience?  What if religious beliefs that mirror common events that occur during a NDE are not the result of a person's preconceived notion of the afterlife, but because that is just the way it really is?