The book presents a number of case studies in a variety of topics involving music and the brain, like epilepsy and music, amnesia and music, or depression and music. There are also case studies involving things like amusia and note-color synesthesia. There are people who get struck by lightning and then becomes obsessed with piano music. Or the people who are unable to speak but are still able to sing. Or the violinist for whom a single note suddenly sounds out of tune.
After each case study, Sacks offers some explanation about what might be going on in the brain to cause these abnormalities.
I found this book absolutely fascinating and devoured it whenever I had a chance until I finished it. It’s well worth the money, especially if you love music and have a nerdy bone in your body.