Look who’s talking now: A study in Cognitive Science links increased exposure to “diminutives” and “reduplication”—words altered slightly to be baby-friendly—with faster learning of new words. University of Edinburgh researchers had the families of 47 English-learning infants record audio of verbal interactions that represent their daily routines (for instance, meal times, bath time and bedtime).
Families submitted the first recordings when their infants were 9 months old, and then again when the infants were 15 and 21 months old. Researchers analysed the language samples to classify when the parent and infant engaged in infant-directed speech, such as iconicity (choo-choo, woof, vroom), diminutives (daddy, mummy, doggy) or reduplication (night-night, din-din). Infants who heard more diminutive words saw an increase in their linear vocabulary growth by 3.17 words per month.
They found that infants who heard more diminutive words had an increase in their linear vocabulary growth by 3.17 words per month. The linear vocabulary of those exposed to more words with reduplication increased by 2.72 words per month. Overall, the mean productive vocabulary size of infants hearing baby talk was 0.7 words at 9 months, 21.6 words at 15 months and 176.5 words at 21 months. Compare these data to those who did not experience baby talk: mean size of vocabulary was 0.4 words at 9 months, 14.5 words at 15 months and 151.8 words at 21 months. “Our findings suggest that diminutives and reduplication, which are frequently found in baby talk words—across many different languages—can facilitate the early stage of vocabulary development,” says lead researcher Mitsuhiko Ota of the University of Edinburgh’s School of Philosophy, Psychology and Language Sciences