Session 4, Keynote Speech: Development in children with Down syndrome - significance and interventions

Carol Stoel-Gammon, Ph.D., Professor Emerita, Department of Speech and Hearing Sciences, University of Washington, Seattle, Washington, USA, csg@uw.edu

This talk presents an overview of speech-language development in children with Down syndrome and compares the nature and timeline of acquisition in this population with data from children with typical development. The focus is on the early stages of development in both groups. Although it is agreed that Down syndrome is associated with a significant delay in linguistic development, there is a lack of consensus regarding the nature of the delay; according to one view, development among children with Down syndrome follows the same time course as in children developing typically, but at a slower rate; in the other view, patterns of language acquisition in children with Down syndrome are qualitatively different from those of children with typical development. The dichotomy reflects a quantitative versus a qualitative interpretation of the differences. However, a closer look at the available data suggests that, in fact, both positions have some support and both can provide insights into the nature of language acquisition in Down syndrome. An understanding of the qualitative and quantitative differences is important for creating appropriate speech-language interventions. A confounding factor in studies and interventions of children with Down syndrome is that developmental patterns are not uniform; in particular, researchers and clinicians must be aware of effects of hearing status and motor skills.

Recent research on speech-language development from infancy through early childhood has highlighted findings from longitudinal studies that allow us to examine the relationships between prelinguistic development and the acquisition of an adult-based speech-language system. Investigations of children with both typical and atypical language development have identified a set of vocal and verbal behaviors that serve as building blocks for language acquisition. The importance of early linguistic "markers" such as the onset of canonical babble (production of CV syllables), appearance of first recognizable words, and rate of growth of a productive vocabulary will be discussed.