if you think about the demons in buddhism, there is a dark, dark side to a spiritual reality. the beginning is just that, that you begin to understand that i might be entering the dark side of something that we generally suspect young humans to do. the other thing that i have thought about is that whether or not it is a spiritual experience , i suspect it may be the dark side of the same coin, i can tell you here how similar it is. if you think about any of the world religions, they had four things in common. some are always aware of their own death.