In addition, Sacks' previous books are all over the footnotes, creating the sense that he's recycling his former work. He repeats anecdotes, inserts irrelevant stories, lapses into the babble of medical jargon.
Sacks is most famous for Awakenings (1973), which recounts how he used L-dopa to awaken victims of "sleeping sickness" from their 40-year torpor. But that book raised important questions: How much of the self is tied to familiar faces, places and cultural markers? What happens when memories get stuck -- and then revived, and then cut off again? In Musicophilia, though, Sacks gets so involved in parading one unusual neurological case after another that significance gets shunted into chapters' final paragraphs -- or nowhere at all.
Sacks uncovers some fascinating insights, however, into the extremes of musical talent and malfunction. Neurologically speaking, for example, those annoying tunes that get stuck in your head ("earworms") are like small, benign epileptic seizures. The neural pathways between the brain and sense organs run in two directions, not just one -- so that after the onset of deafness, for example, the brain sometimes compensates for silence by generating musical hallucinations. Musical training alters brain structure -- particularly if you start at a young age and speak a tonal language like Chinese. Tourette's patients' tics disappear when they join in drum circles. As newborns, we may all be synesthetic (that is, able to see musical tones as colors, for example) until language development crowds out our psychedelic mind-movies.
Discerning memorable conclusions from among Sacks' piled-high case histories, though, can be like disentangling a Bach fugue -- rewarding but onerous work.