Five mechanisms of sound symbolic association.

Sound symbolism refers to an association between phonemes and stimuli containing particular perceptual and/or semantic elements (e.g., objects of a certain size or shape). Some of the best-known examples include the mil/mal effect (Sapir, Journal of Experimental Psychology, 12, 225-239, 1929) and the maluma/takete effect (Köhler, 1929). Interest in this topic has been on the rise within psychology, and studies have demonstrated that sound symbolic effects are relevant for many facets of cognition, including language, action, memory, and categorization. Sound symbolism also provides a mechanism by which words' forms can have nonarbitrary, iconic relationships with their meanings. Although various proposals have been put forth for how phonetic features (both acoustic and articulatory) come to be associated with stimuli, there is as yet no generally agreed-upon explanation. We review five proposals: statistical co-occurrence between phonetic features and associated stimuli in the environment, a shared property among phonetic features and stimuli; neural factors; species-general, evolved associations; and patterns extracted from language. We identify a number of outstanding questions that need to be addressed on this topic and suggest next steps for the field.