The cognitive mechanism behind the Bouba Kiki effect : conventional or synaesthetic sound symbolism?

Abstract

The Bouba Kiki effect shows a sound symbolic association between sound and meaning where “rounded” and “angular” nonwords are matched to rounded and angular shapes (or images) respectively. This effect has been widely replicated across languages and cultures causing speculation for its categorisation as a form of synaesthetic sound symbolism, however the possibility of its classification as a form of conventional sound symbolism, or a combination of both forms of sound symbolism, has not yet been ruled out. Here we investigate sound symbolism within a Maltese adult population. A group of participants was trained to oppose the typical Bouba Kiki pattern via a five-day training programme consisting of alternative forced choice tasks. After the training, the trained experimental group sat for a post-test experiment, while a control group solely sat for the post-test experiment. We report that (i) the typical Bouba Kiki effect can be replicated with naïve participants from a Maltese population using Maltese language as a basis for nonwords, and (ii) when compared to naïve participants who were correct more often on items that followed the typical Bouba Kiki pattern, trained participants were correct more often on items that opposed the typical Bouba Kiki pattern, though that latter preference was not strong and failed to reach significance. While these results cannot completely confirm that the Bouba Kiki effect is a form of conventional sound symbolism or a combination of both synaesthetic and conventional sound symbolism, it suggests that sound symbolic associations can be learnt, warranting further research on cross modal associations via the Bouba Kiki effect.