Evan Kidd & Edith L. Bavin
La Trobe University
The paper reports on an off-line study investigating ambiguity resolution in children aged 5 to 9 years. The study tested predictions of structural and constraint-based approaches to adult sentence processing. It specifically investigated whether proposed constraints override structural attachment preferences for prepositional phrases (PP), predicted by structurally-oriented processing theories. Children (N = 90) aged 5-, 7-, and 9-years were tested on fully ambiguous VP-NP-PP structures. There was manipulation of verb semantics (action verbs versus psychological predicates --- strong constraint), the definiteness of the object NP (weak constraint), and the kind of preposition used ('with' or locative 'on'). A picture-pointing task was used. Two pictures were included for each test item; both could be illustrative of the sentence. Results showed that verb semantics affected children's attachment preferences, with PPs in structures containing psychological predicates more likely to be interpreted as NP-attached than PPs in structures containing action verbs. PPs in structures containing indefinite object NPs were more likely to be interpreted as NP-attached for 5- and 7-year-olds, but not for 9-year-olds, suggesting that children's understanding of the function of the definite article in discourse develops gradually, so supporting research on the development of anaphora. Attachment preferences also differed according to the preposition used. The comprehension data are supplemented by data from an elicited production task using the same test materials. Children were asked to describe each of the two pictures for each test item. The results suggest that the relative strength of constraints on ambiguity resolution, as outlined in the literature on adult sentence processing, may predict the development of interpretation strategies in the 5-9 year age range. Thus developmental data can be used to inform sentence processing theory.