This is my first book by Oliver Sacks. I must admit I was expecting more science, less "novel." Dr. Sacks writes in a literary style and loves multiple complex sentences that make the argument indeed richer, but also intricate. So, if you want a simple reading, you'll be a little surprised.
The book consists of four parts:
4) The World of the Simple
Each section relates to a different set of neurological problems resulting in a mental disorder.
1) In the "Losses" the author describes nine cases.
"Neurology's favourite word is 'deficit', denoting an impariment or incapacity of neurological function: loss of vision, loss dexterity, loss of identity and myriad other lacks and losses of specific functions (or faculties)."
2) In the "Execess" find five "stories".
"What then of the opposite - an execess or superabundance of functions?"
"... we consider their excesses - not amnesia, but hypermnesia; not agnosia, but hypergnosia; and all the other 'hypers' we can imagine."
3) The chapter "Transports" describes six cases.
"...'transports' - often of poignant intensity, and shot through with personal feeling and meaning - tend to be seen, like drimes, as psychical: as a manifestation, perhaps, of unconscious or preconcious activity..."
"...to be seen as psychoses, or to be brodcast as religious revelations, rather than brought to physicians."
4) And at the end of "The World of the Simple" (four "stories"). Dr. Sacks describes cases of people whose neurological disorders outfitted with extraordinary abilities, such as "seeing the numbers," eidetic memory, an excellent sense of smell, etc. (Ie. brilliant savants).
In his book, Dr. Sacks often refers to the study of well-known Russian psychologist A. R. Luria.
Dr. Sacks style of reasoning, not everyone will like it. Besides, there are many similar books, though written from a different perspective than neurological such as "Tales from the Couch: A Clinical Psychologist's True Stories of Psychopathology" by Dr. Bob Wendorf.