Sound Symbolism May Inhibit Later Stages of Language Development: An Object Naming Experiment with Children Aged 3 to 7

Sound symbolism refers to sensory phenomena that associate certain speech sounds with specific impressions and is regarded as a cognitive basis for language learning in infants. However, how sound symbolism serves in later stages of language development, after ca. 5 years of age, remains largely unclear. This study examined the development of sensitivity to sound symbolism in early childhood and its role in language acquisition. Object naming experiments using classic “Bouba-Kiki” paradigm, were conducted with participants aged 3, 5, and 7, as well as adults, to investigate their recognition of sound symbolism and its use in language development. Results revealed that sound symbolism develops later than early language skills and remains incomplete even at age 7, when early stage of language development is nearly completed. Furthermore, an analysis of individual differences in language development, quantified through pronunciation clarity and caregiver evaluations, reveals that infants with heightened sensitivity to sound symbolism may experience delays in language development. These findings suggest that sound symbolism does not unilaterally drive language development in its later stages but instead develops through dynamic interactions, potentially inhibiting progress during this phase.