This study investigates the influence of semantic maturation on early lexical development by examining the impact of contextual diversity--known to influence semantic development--on word promotion from receptive to productive vocabularies (i.e., comprehension-expression gap). Study 1 compares the vocabularies of 3685 American-English-speaking…

Children often find it difficult to map verbs to specific referents within complex scenes, often believing that additional features are part of the referents. This study investigated whether 3-year-olds could use iconic gestures to map novel verbs to specific referents. One hundred and twenty children were taught verbs that could be interpreted as…

Three studies examined 2-year-olds' ability to learn novel words when overhearing these words used by others. Found that children ages 2.5 years were equally good at learning novel object labels and action verbs when they were overhearers as when they were directly addressed. For younger 2-year-olds, this was true for object labels, but results…

Compared the proportions of nouns and verbs in early vocabularies of English- and Mandarin-speaking toddlers and their mothers. Found that Mandarin-speaking children had relatively fewer nouns and more verbs than English-speaking children. When reading books, children's vocabularies were dominated by nouns but not when playing with toys. Mothers…