I have to say I was quite disappointed in this book. The first half read as if the editor said, "your book isn't long enough I need more". So while there's some interesting brain science and biology in there it really didn't add much at all to the discussion of consciousness. In fact one of my major complaints with this book is that it's not until somewhere in the middle that the author even tackles the sticky question of how to define consciousness at all. I had hoped to learn much more from this book and sadly most of the information I'd already come across in other articles that were more interesting and better written.