The shape of boubas: sound–shape correspondences in toddlers and adults

TLDR

Sound–shape correspondences, such as adults linking rounded vowels to rounded shapes and unrounded vowels to angular shapes, are well documented and may influence language development. The study aimed to examine the bouba/kiki effect in 2.5‑year‑old children compared with adults. Researchers presented 20 children and 20 adults with four pairs of rounded versus pointed shapes and four contrasting nonsense word pairs differing in vowel sound. Both age groups matched rounded vowels to round shapes and unrounded vowels to pointed shapes with high significance (p < .0005), and no age difference was observed (p > .10).

Abstract

Abstract A striking demonstration that sound–object correspondences are not completely arbitrary is that adults map nonsense words with rounded vowels (e.g. bouba) to rounded shapes and nonsense words with unrounded vowels (e.g. kiki) to angular shapes ( Köhler, 1947 ; Ramachandran &amp; Hubbard, 2001 ). Here we tested the bouba/kiki phenomenon in 2.5‐year‐old children and a control group of adults ( n = 20 per age), using four pairs of rounded versus pointed shapes and four contrasting pairs of nonsense words differing in vowel sound. Overall, participants at both ages matched words with rounded vowels to the rounder shapes and words with unrounded vowels to the pointed shapes (both p s &lt; .0005), with no significant difference between the two ages ( p &gt; .10). Such naturally biased correspondences between sound and shape may influence the development of language.