Smithsonian.com

The brains of roughly one in 2000 people, more woman than men,  have a curious tendency to blend their senses: sounds have colors, words have tastes. A new study, lead by Olympia Colizoli and described by neuroscientist Neuroskeptic, suggests that people may be able to teach themselves to have these types of experiences, know as synesthetia.

Colizoli et al recruited 17 non-synaesthetes and got them to read books specially printed such that 4 common letters, “a“, “e“, “s” and “t“, were always printed in a certain colour: red, orange, green or blue. The idea was that constant exposure to the coloured letters might trigger grapheme-color synaesthesia, which is a relatively common ‘naturally occurring’ form of the condition.

According to Neuroskeptic, the study wasn’t set up in the best possible way to prove the connection, and the findings of the study were right down the middle: subjects’ agreement with the phrase “I am experiencing color when thinking about certain letters” came in an average 2.5 on a 1 to 5 scale. But the idea is tantalizing enough to be worth pursuing.

Scientists aren’t entirely sure what causes synesthesia, but as neuroscientist David Eagleman says in the above video,

Somehow in a synesthetic brain, these areas [dealing with color] are connecting to these areas [for language], such that words and letters will trigger a color experience.

In essence, this hypothesis suggests that the synesthetic brain is leaky, where signals in one part of the brain cause effects in another.

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