Olivier Messiaen (1908-1992) was a French composer, organist, and ornithologist. Messiaen entered the Paris Conservatoire at the age of 11 and was taught by Paul Dukas, Maurice Emmanuel, Charles-Marie Widor and Marcel Dupré, among others. He was appointed organist at the Église de la Sainte-Trinité, Paris, in 1931, a post held for 61 years until his death. He taught at the Schola Cantorum de Paris during the 1930s. Messiaen perceived colours when he heard certain musical chords (a phenomenon known as synaesthesia); according to him, combinations of these colours were important in his compositional process. His innovative use of colour, his conception of the relationship between time and music, and his use of birdsong are among the features that make Messiaen's music distinctive.