People with synaesthesia, a condition where certain colours or sounds trigger different senses, were found to choose the same colour for a particular sound. The interactive visualisation below lets you see what colours were picked by participants when they heard certain vowel sounds. Vladimir Nabokov, the Russian writer of Lolita, was a synaesthete and saw colours when hearing certain vowels, but many forms of synaesthesia are possible. 'Our findings showed that with lighter colours (yellow, green) associated with more front vowels, or vowels that come from the front of the mouth. 'Darker colours (e.g., red, brown, blue) were associated with back vowels and redder colours were associated with low front vowels.'

Source: Daily Mail April 12, 2019 17:27 UTC