Aural and Written Comprehension by Persons with Down Syndrome

Abstract

We report the results of tests of comprehension in persons with Down Syndrome (DS) of the 10 syntactic structures reviewed in Chap. 2 : simple active sentences; simple passive sentences; active tell sentences with an infinitival complement; passive tell sentences with an infinitival complement; active promise sentences with an infinitival complement; sentences with the predicate eager and an infinitival complement; sentences with the predicate easy with an infinitival complement; gerundial temporal clauses with an active main clause; gerundial temporal clauses with a passive main clause; and active sentences with the main verb choose and an infinitival complement with a missing prepositional object. The tests used were an act-out test with a doll family and a written test in which the participant had to choose between two answers. The participants were persons with DS who could read (25 participants for the act-out and 24 for the written test). A comparison between typically developing children aged 4 to 12 shows an overall similarity between when the structures are acquired by children and persons with DS. However, a comparable leap in performance of typically developing children between ages 4–5 and 7–8 for promise is not found for persons with DS. Despite this, the results of the act-out test for persons with DS show a significant difference in the direction of knowledge of English grammar between tell active and promise. There are also significant differences consistent with English grammar between tell active and tell passive and eager vs. easy sentences. No significant differences between these sentence types were found for the written test, although the difference between eager and easy for some participants is stronger for the written test than for the act-out test. Also in the written test, there were more patterned responses to gerundial temporal clauses. A preference for reference of the embedded null subject of active tell sentences to the linearly nearest NP can account for a higher performance on the written test than the act-out.