Key points are not available for this paper at this time.
In this report we ask how mother-infant interaction affects the rate of early language acquisition. Mothers and 15-month-old infants were videotaped playing at home. Coders described (a) infants' attention to people and/or objects, (b) mothers' use of literal and conventional acts to direct infants' attention and (c) functions of mothers' utterances. Taken together, these aspects of mother-infant play predicted 40% of the variance in infants' vocabulary size at 18 months. Significant unique contributions to this prediction were made by mothers' conven tional object-marking and metalingual use of language. The more mothers highlighted both (a) shared objects using conventional means, and (b) the linguistic code, the greater the variety of words their infants used at 18 months of age.
Smith et al. (Wed,) studied this question.