Thanks very much Mark, this is the kind of discussion about a sensitive topic like consciousness that I really enjoy and appreciate. As a neuroscientist I am sure you are familiar with Christof Koch and his work, likely far more familiar than I am. As he is at the forefront of the study of how matter produces mind, beginning with his work with Crick, I've been interested to see what he says about it. As you likely know, he is or has been an advocate of Tononi's IIT, even saying that the liver is likely conscious to some degree. What I found most fascinating is that he had a self-induced mystical experience in a sensory deprivation tank. It was profound and he commented that the studies of mystics showed drastically decreased brain activity while having the most vivid experiences. He admitted that this may undermine the whole premise of his work in attempting to find not just the neural correlates of consciousness, but how the brain produces it. Personally, I have found hard-nosed accounts of Near Death Experiences hard to account for with a materialist view. So my own inclination is to consider more the filter model, but who knows, and I am just glad the search goes on.