Production of Actives, Passives, and Causatives in Children with Intellectual Disabilities and with Typical Development

This study examined the following aspects of sentence production in children with intellectual disabilities (IDs) and in children with typical development (TD): the production of active, passive, and causative sentences; the effect of focusing on noun phrases; differences in accuracy using case markers and verb morphemes; and the effect of phonological memory on each the voice. In all, 18 children with IDs (mean chronological age [CA] of 13;0 and mean mental age [MA] of 5;9) and 30 children with TD (mean CA of 5;3) participated. The results indicate that the production of passive and causative sentences was more difficult than that of active sentences for both groups. The participants’ production accuracy improved when they focused on noun phrases in active and causative sentences. The children with IDs made more verb morpheme errors than the children with TD, and phonological memory correlated with more accurate production of the passive and causative sentences. We concluded that active sentences are the easiest to produce. In addition, focusing on the noun phrases that represent actor and acted-upon was effective for active and causative senesces. The results also suggest that phonological memory is involved in the production of syntactically complex sentences.