The purpose of this study is to examine the relationship between infant's vocabulary development and mother's verbal interactional style. A total of forty mothers and their infants(13~36 month olds) participated in this study. The maternal verbal inputs during a wordless picture book reading were categorized into 5 verbal interaction styles: attention -getting, explaining, directing, questioning, and feedback-giving. The measures of infant's vocabulary ability were total number of utterances produced, numbers of words, and word types during picture book reading.
Results are as follows: First, mother's feedback were benefit to infant's vocabulary development, especially to infant's word type(R²=.748, p< .001). Second, mother's interaction style gave different impact on different ages. For 13-24 months olds, feedback and attention-getting were significant predictors (R²=.743, R²=.812, respectively, p<.001), whereas for 25-36 months olds, feedback and explaining were significant predictors (R²=.684, R²=.751, respectively, p<.001).
These results demonstrate that it is important for mothers to give verbal responses to infant's words, and that it is needed to interact differently depending on infant's age.