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…

Natural languages contain systematic relationships between verb meaning and verb argument structure. Artificial language learning studies typically remove those relationships and instead pair verb meanings randomly with structures. Adult participants in such studies can detect statistical regularities associated with words in these languages and…

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…

The cross-categorical use of nouns and verbs poses a challenging problem to young language learners because they are known to be less willing to accept that a single form of a word be used for more than one linguistic purpose (e.g., one-form/one-function principle). The present study investigated whether children under 3 years of age are able to…

In many languages, significant numbers of words are used in more than one grammatical category; English, in particular, has many words that can be used as both nouns and verbs. Such "ambicategoricality" potentially poses problems for children trying to learn the grammatical properties of words and has been used to argue against the logical…