The role of child-directed speech in language acquisition: a case study

This paper presents the results of a case study which specifically examines the utterances or input which family members direct at a Japanese infant during the early part of his language development. The data generated by the subject and his parents provide an interesting glimpse into one of the ways in which infants absorb language. The results of the data analysis show that while the parents of the subject were seen to use roughly equal amounts of language with the child, the distribution of language functions used by the mother was importantly different from that used by the father; therefore, it is suggested that this difference in CDS aids the language development of the infant by providing more interactive negotiation, which is argued to be the crucial factor in language development.