Nothing at all about 'spirits' has been 'demonstrated' by 'near death studies'. People who are near death have an uncontrolled release of neurotransmitters, resulting in 'experiences' not unlike a vivid dream or a drug-induced hallucination. There is zero evidence that people 'have' 'spirits'.
I hope you have something better to do this fine Saturday evening than sit around answering this thread, Jeffro. We just went for a walk, had a nice dinner, filled the car for less than two bucks a gallon and returned to find three responses from you on this topic.
Now, regarding the above, I reckon it all depends on what one means by "demonstrated" and "evidence." I recall the words of Thomas Jefferson who, after hearing an account of meteorites falling over Connecticut on December 14, 1807, was reported to have said: "I would more easily believe that two Yankee professors would lie than that stones would fall from heaven."
At that time, even the most learned of scholars would have laughed their heads off at the notion that rocks could fall out of the sky, even though there were credible witnesses who claimed otherwise. In like manner, there are numerous witnesses from all religions and walks of life who claim to have left their bodies, seen and conversed with God, angels; seen visions, and we use various criteria to judge the veracity of what they say. The more skeptical someone is in any given area, whether it be the existence of God, the reality of revelation, life after death, Bigfoot, the Big Bang or the theory of evolution, the more resistance will be exerted as part of the cognitive process. And the more invested someone is to a certain way of thinking, the less resistance will be exerted. I've had personal friends that I've known for years and whom I trust. And though none has ever had a near death experience, they have had experiences that fall into the paranormal range.
The question of the paranormal is one, the question of the theological is another. It seems to me that if one is true, so is the other. If there are evil spirits roaming the earth, it stands to reason that it is balanced by good.
You attempt to explain away near death experiences by saying they're the result of the uncontrolled release of neurotransmitters in the brain. This has never been proven to be the cause of near death experiences, especially when brain activity is flat. Also, this theory cannot explain the exchange of intelligence that takes place -- such as learning things one didn't know, but which are true. Some people can recite conversations that were taking place in other rooms between hospital staff or family members, or scenes they had witnessed many miles away that they were later able to recall in detail.
Atheists shut out things they can't understand, or don't want to understand. Then they resort to ad hominem attacks and ridicule in an attempt to discredit it.