The word “bouba” sounds curvier than the word “kiki” no matter what language you’re used to hearing, New Scientist explains. That odd phenomenon unravels the assumption that words are arbitrary labels and points toward the idea that the sounds we make are directly linked to our experiences:
The turning point came in 2001, when Vilayanur S. Ramachandran and Edward Hubbard, both then at the University of California, San Diego, published their investigations into a condition known as synaesthesia, in which people seem to blend sensory experiences, including certain sounds and certain images (Journal of Consciousness Studies, vol 8, p 3). As many as 1 in 20 people have this condition, but Ramachandran suspected that cross-sensory connections are in fact a feature of the human brain, so that in practice we all experience synaesthesia at least to a limited extent.
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Using similar shapes to those in the original experiment, but changing the names of the invented terms slightly, they found that an astonishing 95 per cent of people labelled the spiky object as “kiki” and the curvy one as “bouba”. One possible explanation is that this might be down to the shapes of the lips as we form the vowels in these words; in “bouba” they are more curved than in “kiki”.
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Benjamin Bergen at the University of California, San Diego…found that the brain processes meanings of pairs of phonaesthemes such as “snore” and “sniff” more quickly than other pairs related simply by their meaning (such as “cord” and “rope”) or their sounds (such as “druid” and “drip”). That is exactly what you would expect if olfaction and the “sn” sound are somehow linked in the brain, says Bergen.
That’s not all. At a recent workshop on sound symbolism in Atlanta, Georgia, he reported that “wh” words associated with words that describe the production of noises such as “whisper”, “whine” or “whirr”, and those beginning with “fl” that tend to signal movement in the air, such as “fly” or “flail”, also enjoyed this fast track in the brain’s processing. Bergen concludes that these may all be forms of sound symbolism.