Like other people who experience this phenomenon, musical notes cause her to see colors; F-sharp makes her see violet, and C makes her see red.
The musician, who remains anonymous and is known simply as ES, also has a much more rare form of the phenomenon: she experiences different tastes when she hears different tones and tone intervals. A minor second is associated with sourness, a major second induces bitterness, a minor third is salty, and a major third is sweet.
Different tones also cause her to experience the tastes of water, both full-fat and low-fat cream, grass, and "disgust."
To test ES's associations, the researchers conducted a test that involved putting a certain flavor on her tongue and having her indicate the tone on a computer keyboard. According to the report, she responded with "perfect accuracy" and faster than non-synesthetic musicians.