Kiki and Bouba

The assocative power of sound goes even further than the links with our past. Kiki and Bouba – originally Takete and Baluba – refer to a particularly interesting sound experiment that shows the extent to which we link sound with vision. It suggests that the shape of a word and its meaning are not random.

The experiment was first conducted by German psychologist Wolfgang Köhler on the Spanish island of Tenerife. The experiment was later repeated many times. Two American researchers, the neuro-psychologists Ramachandran and Hubbard, showed their students the Kiki and Bouba shapes, and asked them: which one is Kiki and which one is Bouba? Over 95% of the students recognised Kiki as the pointy shape and saw Bouba as the rounded shape. But why?

Ramachandran and Hubbard speculated that this is down to the nature of the connections which exist between sensory and motor areas of the brain. That is to say that the visual shape of the object – round or spiky – is linked to the shape our lips make when we say the corresponding word – open and rounded or thin and wide. This is embedded into our DNA and thus in turn linked to the way we move our tongue when we create the word ourselves: Kiki requires you to make a ‘sharp’ movement with your tongue against your palette, while Bouba demands a more ‘rounded’ movement. These associations increase the chance that Bouba is linked to the rounded object and Kiki to the spiky one.

Research carried out in 2003 allowed Ramachandran and Hubbard to provide evidence in support of this theory. They discovered that damage to the part of the brain that is important for language leads to a person being much less likely to associate the rounded object with the word Bouba. The effect is interesting because it helps us shed light on the potential evolutionary origins of language. The fact that so many people, and even young children, consistently assign a sharp word to a spiky object suggests that the way we link sounds to objects is not necessary here done at random. Instead, there is some sort of natural limitation or system in place that helps us to make the association between image and sound. And although having this kind of framework itself is perhaps not sufficient to have brought about the development of language, it may at least be considered a stepping stone for the emergence of verbal communication.