A few decades back, researchers weren’t even sure synesthesia—the mixing of senses that can strongly link words to colors or smells to sounds—was real. But in 1980, the neurologist Richard Cytowic attended a dinner party where the host, Michael Watson, apologized that the chicken didn’t have enough points. Watson explained that “With an intense flavour...I feel shape, weight, texture, and temperature as if I’m actually grasping something," Veronique Greenwood writes for BBC Future. The chicken, Watson said, had come out "all round" instead of "prickly, pointed."
Cytowic was inpsired, and his work helped researchers take the phenomenon seriously. In the past few decades, researchers have investigated what sex is like for people with synesthesia and posited that children may have synesthesia while young, but grow out of it. Genes have been linked with different forms of synesthesia, too.
But even the anecdotal stories of individual synesthetes remain fascinating. For example, Greenwood also spoke to a man who can taste words:
For [James] Wannerton, words are a constant source of distraction because the consonants give them taste. “College” tastes of sausage. “Karen” tastes of yoghurt. “Yoghurt” tastes, foully, of hairspray. “Most” tastes of “crisp, cold toast with hardly any butter on it”.
Wannerton’s ability made reading and studying for school difficult, but writing gave him an opportunity to choose words and tastes. Greenwood reports:
Once, when he was working as a reporter, he spent all night on a 900-word sports story about Northern Irish footballer George Best, choosing the words so that the introduction consisted of hors d'oeuvres tastes, the middle of main courses like roast beef, and the conclusion of dessert. “It was really good fun,” he says. “But the thing that put me off journalism was that the subeditors would swap words.”
The experiences sound unusual and interesting enough that if it really is possible to teach yourself to be synesthetic, the benefits might outweigh the potentially distracting aspects of this blending and crossing of the senses.