Maybe it's because I work in mental health, but I found much of the information in here to be fairly basic and well known. I was hoping for more in depth analysis--what are the long-term effects of drug use on cognition and processing? We know that drug use modifies brain chemistry--the changes that manifest themselves in the genes, are they passed down to the drug addict's offspring? What if the addict stops using--do the genes return to normal? Some of this was addressed in the book. We see a lot of adolescents who have smoked salvia or methamphetamines where I work--do the changes in their personalities and processing last a lifetime, if the person never does the drug again? How maleable is the brain? What about alcoholics? If they sober up and stay that way, can the brain recover? And how does this manifest itself in their day to day lives? I had a lot of questions (clearly) and wasn't satisfied with the depth of the answers the book provided. The author is obviously very knowledgable--I think this book was written specifically for the lay person. Also, his use of exclamation points kind of drove me nuts, but that may just be me.