NONVERBAL-COMMUNICATION AND EARLY LANGUAGE-ACQUISITION IN CHILDREN WITH DOWN-SYNDROME AND IN NORMALLY DEVELOPING-CHILDREN

Many children with Down syndrome display asynchrony in development wit h the acquisition of language preceding at a slower pace than the acqu isition of other cognitive skills. Recent research suggests that the e xpressive language delays that are displayed by these children may be associated with an earlier disturbance in the development of nonverbal requesting skills (Mundy, Sigman, Kasari, & Yirmiya, 1988; Smith & vo n Tetzchner, 1986). To test this hypothesis, a longitudinal study of 3 7 children with Down syndrome and 25 children with normal development was conducted. The results of the study indicated that this sample of children with Down syndrome exhibited a disturbance in nonverbal reque sting. Furthermore, individual differences in nonverbal requesting wer e associated with the subsequent development of expressive language in these children. This association was observed even after taking into account initial variance in developmental level and language status. T hese data suggested that some of the processes involved in the express ive language delay of children with Down syndrome were not unique to l inguistic development. Instead, some aspects of this delay appeared to be associated with problems in an earlier nonverbal phase of communic ation development. Additionally, the results suggested that measures o f nonverbal communication skills also made a unique contribution to th e prediction of language development among children with normal develo pment. These data supported the hypothesis that the acquisition of non verbal communication skills provides an important foundation for the e mergence of language in atypical as well as typical development.