You are here:

• Macquarie Home »
• Faculty of Human Sciences »
• Department of Linguistics » Child Language Lab

Home	Research	Publications	Corpora	People	Get Involved	Contact us

Ongoing Research Projects

Prosodic and Articulatory Constraints on Phonological Development

One of the issues we have been investigating is the nature of the constraints on the shape of childrens early Prosodic Words. This appears to depend on the distribution of word and foot structures found in the target language. Recent research has also examined the development of syllable structures. Some of this work finds that coda consonants are more likely to be produced in stressed and final syllables, both of which exhibit increased duration, suggesting that this facilitates the articulation of more segments. Other research has focused on the acquisition of word-final clusters, raising questions about the competing contributions of frequency, morphology, and structural/sonority/articulatory factors in predicting the course of cluster acquisition across languages. These issues are currently being explored acoustically and gesturally using ultrasound, examining childrens early representation of feature cues to segmental contrasts and how this develops articulatorily.

Interactions at the Phonology/Morphology Interface

One of the classic problems in language acquisition is variability in the production of grammatical morphemes. We have been investigating the possibility that much of the within-speaker variability in morphological production can be understood in terms of prosodic (contextual) constraints. Some of our research has shown that English learners are more likely to produced grammatical morphemes like the 3rd person singular s in phonotatically simpler contexts, especially at the ends of phrases. Other research shows that French, English, and Sesotho learners are more likely to first produce determiners and noun class prefixes with monosyllabic nouns, and only later with nouns containing 2 or more syllables. These findings suggest that grammatical morphemes may be acquired earlier in contexts where they are prosodically licensed, pointing to a closer link between the acquisition of phonology and morphology than syntacticians typically assume. The various contributions of lexical effects are currently being explored with other morphemes and other populations (SLI, bilinguals and L2 speakers).

Syntactic Generalization

We have long been interested in how and when children begin to make syntactic generalizations. Some of this research has been carried out in Sesotho, where the high frequency of passives appears to facilitate earlier acquisition of this construction than in English. On the other hand, Sesotho-speakers also exhibit generalization to low-frequency double-object applicatives, where word order is influenced by animacy rather than thematic role. Recent work on English dative shift and transitive/intransitive alternations also shows early generalization of new syntactic frames with novel verbs.

Downloads

• Download the video [5.30MB] (might take awhile to download)

The Nature of the Input and Implications for Learnability

The starting point for much of our research is determining the nature of the input children actually hear. This involves detailed study of child-directed speech corpora. Armed with this information we can better address the nature of the learnability problem. Much of this research examines the nature of the input at different levels of structure (i.e., syntactic, lexical, morphological, segmental, acoustic/phonetic) and makes predictions about the course of development of certain structures crosslinguistically. This is complemented with probabilistic modeling of the learning process (see joint work with Mark Johnson), in an attempt to discover what types of procedures learners may use in solving the problem of language learning problem.

Research Opportunities

PhD students and postdocs interested in pursuing any of these areas of research should contact Katherine Demuth. Undergraduates interested in gaining research experience, or doing Honours should enquire by October 1.