Influence of Language Load on Speech Motor Skill in Children With Specific Language Impairment

Abstract

Children with specific language impairment (SLI) show particular deficits in the generation of sequenced action - the quintessential procedural task. Practiced imitation of a sequence may become rote and require reduced procedural memory. This study explored whether speech motor deficits in children with SLI occur generally or only in conditions of high linguistic load, whether speech motor deficits diminish with practice, and whether it is beneficial to incorporate conditions of high load to understand speech production. Children with SLI and typical development participated in a syntactic priming task during which they generated sentences (high linguistic load) and, then, practiced repeating a sentence (low load) across 3 sessions. We assessed phonetic accuracy, speech movement variability, and duration. Children with SLI produced more variable articulatory movements than peers with typical development in the high load condition. The groups converged in the low load condition. Children with SLI continued to show increased articulatory stability over 3 practice sessions. Both groups produced generated sentences with increased duration and variability compared with repeated sentences. Linguistic demands influence speech motor production. Children with SLI show reduced speech motor performance in tasks that require language generation but not when task demands are reduced in rote practice.