You have no doubt heard of synesthesia, the slightly trippy phenomenon of one sense triggering another. It used to be considered rare, but it is now thought that one in every 25 people are synesthetes.
The way it manifests from one person to the next can vary considerably. While one person might "feel" another person being tickled (mirror-touch synesthesia), another might associate the name "Ross" with a Gregg's sausage roll. (Yes, apparently that is a thing.) Yet another might "see" explosions of blue, yellow, and bubblegum pink whenever Bowie's Life on Mars plays on the radio. Etcetera, etcetera.
Still, the most commonly recognized form of synesthesia is the association of certain letters or numbers with a particular color. And, now, it appears that this is something most of us do – at least, to some extent. According to a study published in the journal Behavior Research Methods, around 70 percent of us associate different vowel sounds with a color, even if it's not necessarily to the same consistency as someone with fully fledged synesthesia.
Researchers at Radboud University in the Netherlands and the University of Edinburgh in the UK came to this conclusion after testing for color-vowel associations in 1,164 Dutch volunteers, around 200 of whom were synesthetes.
In one test, participants were asked to select the shade they felt best represented certain vowel sounds, for example, the "aa" sound in "baa". (Definitely a dark yellow.) In another, they were asked to identify the color that "best fit" a particular digit, which could be any letter from A to Z or any number from 0 to 9. To find out how systematic these associations were, the researchers then compared each person's answers to a random sample of 10,000 random associations.
There seemed to be greater associations between vowel sounds and colors than between digit appearances and colors, with participants generally picking lighter, greener, yellower colors for "front vowels" (like the "ee" in "need", the "i" in "sit", and the "a" in "cat") and darker, redder, bluer colors for "back vowels" (like the "oo" in "boot", the "ou" in "should", and the "aw" in "paw"). However, there were noticeable differences in the colors selected by synesthetes, who tended to be more "systematic" in their choices, the researchers say.
Those with synesthesia tended to pick colors that were more extreme. They were more likely to pick dark and blue colors, generally speaking. Yet, they were also significantly more likely to pick yellow colors for the "front vowels".
These are just generalizations but it suggests there is "a logic to how we link sound and color, and the structure of language has an important role in this process," Mark Dingemanse, one of the researchers involved in the study, said in a statement.
"You could say that the vowels have to pass through the sorting machine that is our language before we can link colors to them, even in synesthetes, for whom associations like these are involuntary."
What you choose to do with this new information is up to you.
