Ms Anina Rich and Dr Jason Mattingley with a tool for testing synaesthetes' cross-sensual perception. Letters can be shown singly and in any colour.
Subjects colour the letters to replicate their perception.
Sometimes I get people's names muddled up. For example I may call someone 'Debbie' when she is really 'Paula' because D and P are more or less the same colour green. Tuesday is yellow. The researchers presented letters and digits in different colours which either matched the synaesthetic colour of the character, or did not match. Synaesthetes were much slower to name the colour presented when the actual colour conflicted with the synaesthetic colour of the letter.