Group items tagged

Dr. Mitsuhiko Ota, a linguist in the University of Edinburgh Language Sciences department, was the lead researcher in a 2018 study (Ota, Davies-Jenkins, and Skarabela 2018) examining infant-directed speech, a.k.a. baby talk. Across languages, lexical items specific to infant-directed speech (i.e., 'baby-talk words') are characterized by three major features: 1. onomatopoeia incorporated into non-arbitrary, "highly iconic" words, e.g. "quack", "bow wow" 2. diminutives, e.g. "daddy", "tummy" 3. reduplication, e.g. "din din", "easy peasy" These three lexical characteristics may help infants discover the referential nature of words, identify word referents, and segment fluent speech into words. If so, the amount of lexical input containing these properties should predict infants' rate of vocabulary growth. To test this prediction, Ota's team tracked the vocabulary size in 47 English-learning infants from 9 to 21 months and examined whether vocabulary growth was related to measures of iconicity, diminutives, and reduplication in the lexical input at 9 months. The team's analyses showed that both diminutives and reduplication in the input were associated with vocabulary growth, although measures of iconicity were not. These results are consistent with the hypothesis that phonological properties typical of lexical input in infant-directed speech play a role in early vocabulary growth.