Brains
Recently, I was reading some of Timothy Leary's writings, in which he looks at aspects of brain in relation to 'bardo' states. Many people are drawn to experiment with hallucinogens as a form of recreation. It was the ideas of Aldous Huxley and of shamanism which led me to experiment with cannabis, magic mushrooms and acid as a quest as I had already had some intense borderline sleep experiences.
So, the idea of psychedelic experimentation and experience may be for some a pursuit of understanding of the brain, mind and the nature of reality. When I took acid I definitely had some strange experiences in that respect. During the first trip I had the sense of there being no God, which I had not thought previously. Also, for some time afterwards I noticed I was having coordination problems and felt as if I had been out of my body and had not got back into it in an aligned way. This was the reason why I tried it again and during the second trip, in a warehouse dance event, I had a definite experience which felt like it involved a certain dualism. I felt able to walk through people and when I looked in a mirror I saw a reflection of the walls and environment but not myself. That was unnerving and I thought that I had lost my body..
It may be that the psychedelic experiences cannot be taken at face value, like with NDEs. However, for some people, such experiences may lead to a sense of there being other levels of reality beyond the physical perceived in day to day consciousness.