Abstract
Do children with severe learning disabilities develop through the same stages as children without such problems, but more slowly, or do they develop along different lines? The "delay" versus "deviance" issue is a long-standing and familiar one that has surfaced in discussions of several different groups of developmentally disabled children. In this paper, Professor Rondal explores the issue in relation to linguistic development in children with Down's syndrome. He finds the traditional distinction and debates about delay versus deviance conceptually ill-founded. He explores, in the light of contemporary empirical evidence, an alternative and more "transactional" approach.