I'd like to know your opinion when you read it. It's in my list too, I have read and enjoyed a lot several books by Dr. Sacks and his might be a refreshing take on the subject.
I mean, there's not many books discussing this from a non-necessarily activist/counter-culture point of view. And Sacks, besides being a walking encyclopedia about brain happenings, had personal insights that admittedly helped him to reach and understand many people who, in the eyes of most classic, cold-blooded neurologists, would have been shunned and misunderstood.
When I read "The Man Who Mistook His Wife For A Hat", one of the chapters that struck me the most was "The dog beneath the skin". You might know it. It describes the case of Stephen D., who after drugs consumption (stimulants, PCP) had an extremely vivid dream of being a dog in a world full of intense smells, and woke up to find himself precisely in a world like that, being able to perceive incredible subtleties in scents of people, places and materials for a period of three weeks. It was an amazing account of "hyper-function" that talked about dormant senses and abilities in our species.
The best bit was finding out that, years after the book was published, Oliver Sacks eventually admitted that he was Stephen D.
"The Menu is Not The Meal." - Alan Watts