The Acquisition of Nominal Compounding in Japanese: A Parametric Approach

The Principles-and-Parameters approach (Chomsky 1981) postulates that UG consists of the set of universal principles that are satisfied by any language, and parameters that define the points and the range of possible human languages. Under this approach, the process of language acquisition is a process of fixing the values of such parameters, and thus the elucidation of genetically endowed parameters is one important goal of linguistic investigation. Recently, on the basis of overwhelming cross-linguistic and acquisitional data, Snyder (1995, 2001) claims that the availability of novel nominal compounding in a given language is constrained by the Compounding Parameter, which also restricts the possibility of various complex predicate constructions. Many other studies have provided arguments for the existence of this parameter, demonstrating that children who speak languages such as English and Japanese acquire these two properties at the same time, around three years of age at the latest (e.g., Isobe & Sugisaki 2000, Snyder & Stromswold 1997, Sugisaki & Isobe 2000). In contrast, an intriguing experimental result is reported by Choi & Mazuka (2003) and Choi (2003) that 6-year-olds who speak Korean, which permits both nominal compounding and complex predicates, did not reliably disambiguate structurally ambiguous sentences containing either Subject-Object sequence or a novel nominal compound. The key to resolving such ambiguous sentences is the prosody, the role of which has attracted more attention in the fields of both syntax and acquisition these days (e.g., Kitagawa 2005, Gualmini et al. 2002). In light of this situation, this paper investigates experimentally whether young Japanese-speaking children can resolve the structural ambiguity between a Topic-Object sequence and a nominal compound, by using prosodic information. I argue that this finding not only provides a new piece of evidence that they have adult-like knowledge with respect to nominal compounding, but lends further support to the theory of the Compounding Parameter.