Children With Specific Language Impairments Perceive Speech Most Categorically When Tokens Are Natural and Meaningful

Abstract

Purpose To examine perceptual deficits as a potential underlying cause of specific language impairments (SLI). Method Twenty-one children with SLI (8;7–11;11 [years;months]) and 21 age-matched controls participated in categorical perception tasks using four series of syllables for which perceived syllable-initial voicing varied. Series were either words or abstract nonword syllables and either synthesized or high-quality edited natural utterances. Children identified and discriminated (a) digitally edited tokens of naturally spoken “bowl”–“pole”, (b) synthesized renditions of “bowl”–“pole”, (c) natural “ba”–“pa”, and (d) synthetic “ba”–“pa”. Results Identification crossover locations were the same for both groups of children, but there was modestly less accuracy on unambiguous endpoints for children with SLI. Planned comparisons revealed these effects to be limited to synthesized speech. Children with SLI showed overall reduced discrimination, but these effects were limited to abstract nonword syllables. Conclusion Overall, children with SLI perceived naturally spoken real words comparably to age-matched peers but showed impaired identification and discrimination of synthetic speech and of abstract syllables. Poor performance on speech perception tasks may result from task demands and stimulus properties, not perceptual deficits.