The list of things scientists still don’t know about synesthesia — the blurring of the boundaries between the senses, the condition that allows people to taste sounds or hear colors — may outweigh the list of things they do. For one thing, no one knows for sure how many people have it, in part because there are so many different forms and in part because some people may not realize their experience is outside the norm. Its causes are still somewhat mysterious, too.
Scientists do have a few ideas, though. As a recent New Scientist article explained, some believe that genetics plays a role, while others think it may have something to do with levels of the neurotransmitter. And one of the most common theories is that synesthesia is “hardwired,” the result of certain connections in the brain that are typically pruned away.
That last one may have just gotten a boost in the form of a paper recently published in the European Journal of Neuroscience. The study describes the case of a woman, identified only as AB, who has a form of synesthesia in which certain elements of music — the notes, the volume, even the instrument being played — cause her to see different colors.
While this particular form of synesthesia isn’t the rarest, AB’s bad luck puts her in a category all her own: Over a small handful of years, she contracted viral meningitis, suffered multiple concussions and migraines, and was even was struck by lightning. (“To say she had a series of unfortunate events would be an understatement,” author Kevin Mitchell, a neuroscientist at Trinity College Dublin, told New Scientist.) And with each successive trauma, the magazine explained, her synesthesia changed, sometimes shifting slighting and sometimes temporarily disappearing altogether: “For a month after meningitis, the colours she associated with musical notes changed. One concussion moved her colours from the centre of her vision to the periphery. Migraine medication and the lightning strike both stopped her synaesthesia.”
The remarkable thing about all this (besides the fact that she was struck by lightning) is that no matter what chased it away, AB’s synesthesia always reappeared. A similar thing happened with another patient described in the paper, a man nicknamed CD, who found that Ritalin altered the colors of his synesthesia and antidepressants halted it altogether; when he stopped taking his medication, though, his music–color link returned to its usual state.
Together, the researchers argued, these two cases lend more weight to the idea that the condition is anatomical, something built right into the structure of the brain: “The underlying neural substrates mediating specific synaesthetic pairings appear remarkably ‘hard-wired’ and can persist over very long periods even under conditions that alter or completely suppress the conscious synaesthetic experience itself,” they wrote. Or, to put it more plainly: You can mask the symptoms of synesthesia for a time, but the underlying cause seems pretty much impossible to shake. Something to consider before you teach yourself a new, sense-blurring skill.