Developmental Transformational Capacity of Children with Down's Syndrome

This study examined the generative-transformational capacities of two groups of children with Down's Syndrome with mean mental ages of 3,6 yr. and 4,6 yr. respectively. A sentence repetition task was used to assess their knowledge of selected transformational sentence types (simple-active-affirmative-declarative, question, negative, passive and negative-passive). There were significant effects of groups and sentence types but a nonsignificant interaction of groups × sentence types. These results were taken as support for Lenneberg's “slow motion” hypothesis of language development in mentally retarded children. Children with Down's Syndrome appear to follow the same patterns of grammatical acquisition as normal children but at a reduced rate associated with the severity of their retardation.