Long TextExercise 75 of 83

For most people, hearing a piece of music and seeing a flash of colour are entirely separate experiences. But for a small percentage of the population - estimated at between two and four percent - these senses overlap in ways that can seem extraordinary to the rest of us. The condition is known as synaesthesia, and…

• What does the writer say about how synaesthesia was regarded in the past?
• What evidence confirmed that synaesthesia is a genuine neurological experience?