Effects of Acquisition Rate on Emergent Structure in Phonological Development (2007)
Individual differences in child phonologies are often correlated with the rate at which language is being acquired. The correlation suggests some relationship between acquisition rate and language structure, but the nature of this relationship is not well understood. This article presents a computational model, the Vocabulary Expansion Model (VEM), designed to explore how acquisition rate might interact with other constraints on phonological development to give rise to rate-dependent differences in the structure of words in a developing vocabulary. In VEM, words from a simulated adult target vocabulary are evaluated according to well-specified articulatory and perceptual costs, and selected into child vocabularies at different rates. Comparisons of the structure in the simulated child vocabularies show that words acquired early during vocabulary development have simpler phonological structures than words acquired later, and that slow word acquisition results in vocabularies with shorter words, simpler segments, greater segment to segment similarity, and simpler syllable structures than more rapid word acquisition. These results are qualitatively similar to the intra- and interindividual differences observed in children with normal and delayed language, suggesting that at least some of the structural differences may emerge from the rate at which children acquire words.
Language:737-769, 2007.

Risto Miikkulainen Faculty risto [at] cs utexas edu
Melissa Redford Postdoctoral Alumni redford [at] cs utexas edu