The effect of probabilistic phonotactics on lexical acquisition

The effect of probabilistic phonotactics on lexical acquisition in typically developing children was examined to determine whether a lexical or sublexical level of language processing dominates lexical acquisition. Sixty-one normally achieving 7, 10, and 13 year-old children participated in a word learning task, involving non-words of varying probabilistic phonotactics. Non-words were presented in a lecture format and recognition memory was tested following a 7 minute filled delay. Results showed that 10 and 13 year-old children recognized more high probability non-words than low probability non-words. In contrast, 7 year-old children showed no consistent effect of probabilistic phonotactics on lexical acquisition. These findings suggest that the sublexical level of processing dominates word learning during the initial phases in older children. This, in turn, raises questions about the mental representations of words and the effect of phonological knowledge on lexical acquisition in young children. Implications of these findings for children with specific language impairment (SLI) are discussed.