Signing and lexical development in children with Down syndrome.

Language development in children with Down syndrome is delayed, on average, relative to general cognitive, motor and social development, and there is also evidence for specific delays in morphology and syntax, with many adults showing persistent problems in these areas. It appears that the combined use of signed and spoken input can boost early language development significantly, this evidence coming initially from single case-studies, and more recently from larger scale controlled studies. Research with typically developing hearing and deaf children, as well as children with Down syndrome, has demonstrated the importance of establishing joint attention for vocabulary development. Furthermore, studies carried out with children with Down syndrome indicate that reducing attentional demands may be especially important in scaffolding language development in this group. The use of signing strategies which have been found to facilitate language development in deaf children when signing to children with Down syndrome is discussed, as is the need for further research on this topic and on the importance of joint attention for the use of other augmentative and alternative communication systems, such as graphic symbol and picture systems.