This historical review describes the brain disease which afflicted the great impressionist-classicist composer Maurice Ravel (1875-1937). The usual interpretation of the symptoms Ravel exhibited during his disease is primary progressive aphasia / Pick's disease. Some authors see this as the cause for his lost musical creativity during the last years of his life. By contrast, in our review it is presented why a car accident in 1932, with the probable consequence of a mild to moderate traumatic brain injury, could be the key event in his life, triggering the loss of his ability to compose. In addition, the influence of Ravel's disease on his musical style is evaluated. Although some authors see a link, we try to explain why there is no clear evidence for this.