History is full of people who saw the world a little more colorfully than the average person. The novelist Vladimir Nabokov saw letters as objects in nature. Wassily Kandinsky’s seemingly nonsensical painting collages are heralded because of the artist’s unique ability to “hear,” “touch,” and “smell” color. Genius physicist Richard Feynman often described the colors in his equations.
All of these figures were tied together by one mysterious brain quirk: synesthesia, the neurological condition in which one sense (say, your vision) is associated with another sense (say, taste). “Taste the rainbow” might be a tagline for a Skittles ad, but for some synesthetes it’s a very real representation of their world. The condition is rare and often associated with colors and letters, but as the Science of Us detailed last year, any intersection of senses counts as synthesia, like the man who feels the sensations that other people feel.
On this week’s The Gist podcast, we not only learn that host Mike Pesca is a synesthete (his is the type that sees colors in letters), but that, per his guest, science writer Maria Konnikova, we were, perhaps, all born synesthetes.
To be sure, this isn’t a new theory. Enlightenment-era philosopher Jean-Jacques Rousseau wrote up a funky thought experiment posing as a novel, Emile, in 1762, proposing that if a person grew up to be an adult but retained the brain of a child, they would have synesthesia, where “His eye would not perceive colour, his ear sounds, his body would be unaware of contact with neighboring bodies, he would not even know he had a body. All his sensations would be united in one place, they would exist only in the common ‘sensorium.’”
Of course, testing whether an infant is a synesthete is nearly impossible, particularly because very young children don’t really understand how to separate their burgeoning senses, so Rousseau’s theory was considered just a thought experiment for years. But the idea of infant synesthesia picked up steam again in the late 1980s, when psychologist Daphne Maurer used a burgeoning technology — anatomical tracing, which followed neurons as they developed over time — to defend the idea that babies had levels of synesthesia that disappeared as time went on and they grew up.
And in 2011, Maurer’s theory got a scientific boost from Katie Wagner and Karen R. Dobkins, who published a revolutionary study in Psychological Science. The two psychologists showed infants and adults pictures featuring either repeating circles or repeating triangles on a split-color background (one side was either red or blue, the other was either yellow or green). Infants don’t understand shapes and colors as concepts, but they do like to stare at things (as Konnikova points out during the podcast, it’s a “mark of attention”), and so Wagner and Dobkins figured if the babies looked at a certain background/shape combination, they were unconsciously associating the two, or otherwise exhibiting signs of synesthesia. The results: The infants were definitely drawn to the shape-color associations, particularly if they were a few months old. But by the time the babies hit 8 months, the shape-color staring had worn off, indicating that it wasn’t something that clicked in their brains anymore.
So it might be that we’re all at least slightly synesthetic at birth and that some sort of “pruning” occurs in most of us as we develop, but that pruning doesn’t occur for synesthetes like Pesca. But we’re going to need some more scientific testing to figure out whether or not babies have synesthesia and, if so, why our ultra-sensual world disappears as we age.