What is "sonochromatism"

Sonochromatism or sonochromatopsia ( Latin: Greek: Greek: -opsia (seeing)) is a neurological phenomenon in which colours are perceived as sounds. The phenomenon is created by the union between a brain and a colour-to-sound software or chip. People who report such experiences are known as sonochromats. The term was coined by Neil Harbisson to differentiate his experience of colour from people with chromesthesia or colour-to-sound synesthesia.