Was Maurice Ravel's illness a corticobasal degeneration?

The French composer Maurice Ravel (1875-1937) was struck down at the peak of his career by an aphasia and apraxia that destroyed his artistic realization but preserved his musical sensibility and judgment. He died after craniotomy. Multiple hypotheses have been formulated to explain the exact nature of his illness, probably corticobasal degeneration. However, in the absence of a post-mortem examination, the diagnosis must remain speculative despite the accurate descriptions of the symptoms in numerous biographies, the neuro-psychological notes of Théophile Alajouanine and the operative findings of Clovis Vincent.