I like this discussion on the dark side of meditation and the issues that can occur. I view them of course not necessarily from a scientific or even scholastic perspective. I come to this discussion from personal experience ( which is king in my book) and a shamanic eye. It is necessary to have this discussion because these are real consequences of awakening a possible shaman without the lore/ guiding hand/ shamanic ethos and spirit contact. Meditation is not a practice of scientifically silencing the mind and it's voice, it is a conscious effort to connect yourself with the divine part of yourself and divinity as we are able to perceive and understand. This requires understanding of uncommon sense to be applied in a common sense world. Yes this is indeed a paradox, but if you are in the mirror's reflection, everything is backward, yet we still understand it.
I agree with the Dalai Lama: you cannot have a Temple without a large library to support it. ( Library guides are also very much desired.) Libraries and library guides teach us that there are answers out there and if they are not direct answers, we are able to take the facts or read a pattern and bring it into focus to understand or at least come to terms with the strangenesses currently in play. Between libraries and meditation, shamans thrive; remove the libraries and the whole kit and caboodle is insanity in a crazy burlap bag of angry wet cats.
I have had some very negative experiences in both meditation and trance. That does not make me unstable. It makes me pretty "normal."
Thus the witch proverb:
Faithfully serve your imp, and S/He shall faithfully serve you.