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Updated: May 4, 2026

Investigating the Effect of Visual Imagery and Learning Shape-Audio Regularities on Bouba and Kiki
Published on: September 13, 2019
Early sound symbolism for vowel sounds
Ferrinne Spector1, Daphne Maurer2
1Department of Psychology, Neuroscience & Behavior, McMaster University, Hamilton, Ontario, Canada, and Psychology Department, Edgewood College, Madison, WI, USA;
Abstract:
Children and adults consistently match some words (e.g., kiki) to jagged shapes and other words (e.g., bouba) to rounded shapes, providing evidence for non-arbitrary sound-shape mapping. In this study, we investigated the influence of vowels on sound-shape matching in toddlers, using four contrasting pairs of nonsense words differing in vowel sound (/i/ as in feet vs. /o/ as in boat) and four rounded-jagged shape pairs. Crucially, we used reduplicated syllables (e.g., kiki vs. koko) rather than confounding vowel sound with consonant context and syllable variability (e.g., kiki vs. bouba). Toddlers consistently matched words with /o/ to rounded shapes and words with /i/ to jagged shapes (p < 0.01). The results suggest that there may be naturally biased correspondences between vowel sound and shape.
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