Janet Pierrehumbert - Northwestern; New Zealand Institute of Language, Brain and Behavior
Regularization in Language Learning and Change
Language systems are highly structured. Yet language learners still encounter inconsistent input. Variation is found both across speakers, and within the productions of individual speakers. If learners reproduced all the variation in the input they received, language systems would not be so highly structured. Instead, all variation across speakers in a community would eventually be picked up and reproduced by every individual in the community. Explaining the empirically observed level of regularity in languages requires a theory of regularization as a cognitive process.
This talk will present experimental and computational results on regularization. The experiments are artificial language learning experiments using a novel game-like computer interface. The model introduces a novel mathematical treatment of the nonlinear decision process linking input to output in language learning. Together, the results indicate that:
The Cognition & Language Workshop is a Geballe Workshop sponsored by the Stanford Humanities Center. We gratefully acknowledge the Humanities Center's support, and additional support from the Center for the Study of Language and Information.
CHALLENGES AND SUPPORT FOR VERB LEARNING
Young children the world over appear to expect that a verb presented in a transitive frame surrounded by nouns maps onto a causative meaning and is best associated with an event involving an agent and a patient. At the same time, however, they struggle when a verb appears in an intransitive frame in which two conjoined nouns occupying the subject position. This contrast in performance between the two syntactic environments has been replicated time and again across labs, and has led some researchers to conclude that the fault lies in children’s underdeveloped syntactic representations or in the heuristics they deploy to assign semantic roles to a verb’s arguments. However, I will present the results of a set of word learning studies demonstrating that not only do adults also flounder when presented with a novel verb in an intransitive frame, but when children are provided with semantic support for the form-meaning mapping in the form of an additional informative lexical item or distributional evidence concerning the intended interpretation of the syntactic frame in the discourse, they fare much better with the intransitive frame. These findings suggest that the problem may not be an immature grammar, but rather lack of sufficient information to narrow down the hypothesis space. Verb learning calls upon children’s syntactic, semantic, and pragmatic knowledge. When these aspects of the linguistic system work in concert, mapping form to meaning is facilitated.