Examined the role of exposure to speech in children's vocabulary growth. Characterized vocabulary growth rates for children from 14 to 26 months of age. Found a relation between individual differences in vocabulary acquisition and variations in the amount of a mother's speech to her children. (BC)

Examined the extent to which maternal linguistic input enabled children to use syntactic bootstrapping. Studied uses of 25 common verbs in speech of 57 mothers to their 1-year olds and 2-year olds. Found that verbs can be used to create informative syntactic frames, syntactic frames can cue appropriate verb class, and multiple syntactic framing…