The first stage of combinatorial speech is better described as variable than uniform. Talk of variants obscures two different aspects of language (knowledge and use) and two different aspects of language development -- acquisition of the grammar (competence) and deployment of the grammar in speaking and listening (performance). Null subjects and…

In successful communication, it is critical to have the ability to identify what a speaker is referring to from previously mentioned information. This ability requires the identification of the topic initially introduced by lexical forms and its continuity in discourse expressed by anaphora such as null and pronominal forms in the subsequent…

When linguistic input contains inconsistent use of grammatical forms, children produce these forms more consistently, a process called "regularization." Deaf children learning American Sign Language from parents who are non-native users of the language regularize their parents' inconsistent usages. In studies of artificial languages…

How does linguistic structure affect children's developing cardinal number knowledge? The bootstrapping theory proposes that children might use syntactic information provided by known words such as quantifiers to bootstrap the meanings of unfamiliar words such as number words. Prior studies of numeral and quantifier development have indicated that…

Research in language development has only recently begun to focus on the inherent variability of language. Previous studies have explored at what age children begin to produce variable linguistic forms and how these forms progress through development. While children produce adult-like variation early on, some variable forms take longer to acquire…

This study investigated age differences in the utilization of visually contrastive information (i.e., differently colored identical objects) for temporary referential ambiguity resolution during spoken sentence comprehension. Five- and 6-year-old Japanese children and adults listened to sentences that contained a color adjective-noun combination…

We tested 12- and 18-month-old English-learning infants on a preferential-looking task which contrasted grammatically correct sentences using the determiner "the" vs. three ungrammatical conditions in which "the" was substituted by another English function word, a nonsense word, or omitted. Our design involved strict controls…

Children and adults follow cues such as case marking and word order in their assignment of semantic roles in simple transitives (e.g., "the dog chased the cat"). It has been suggested that the same cues are used for the interpretation of complex sentences, such as transitive relative clauses (RCs) (e.g., "that's the dog that chased…