Can children learn abstract syntactic principles by using general cognitive capacities?

One of the most hotly debated issues in the study of language acquisition is whether the abstract syntactic principles of a language can be learned by children

1. by using domain-general capacities (such as pattern finding, analogy, statistical learning, categorization and generalization, etc.)

or whether they need

2. innately specified knowledge of language that enables them to form the right abstract syntactic categories that cannot be infered from the surface level of linguistic utterances (Chomsky's Poverty of Stimulus Argument)

In a new paper in the journal Cognition, Perfors et al. (2011) argue that domain-general capacities are sufficient for children to be able to learn abstract syntactic principles inherent in the linguistic input.

Here's the abstract:

Children acquiring language infer the correct form of syntactic constructions for which they appear to have little or no direct evidence, avoiding simple but incorrect generalizations that would be consistent with the data they receive. These generalizations must be guided by some inductive bias – some abstract knowledge – that leads them to prefer the correct hypotheses even in the absence of directly supporting evidence. What form do these inductive constraints take? It is often argued or assumed that they reflect innately specified knowledge of language. A classic example of such an argument moves from the phenomenon of auxiliary fronting in English interrogatives to the conclusion that children must innately know that syntactic rules are defined over hierarchical phrase structures rather than linear sequences of words (e.g., [Chomsky, 1965], [Chomsky, 1971],[Chomsky, 1980] and [Crain and Nakayama, 1987]). Here we use a Bayesian framework for grammar induction to address a version of this argument and show that, given typical child-directed speech and certain innate domain-general capacities, an ideal learner could recognize the hierarchical phrase structure of language without having this knowledge innately specified as part of the language faculty. We discuss the implications of this analysis for accounts of human language acquisition.