Abstract: | The behavior of eight infants with Down syndrome was observed biweekly from 8 to 24 weeks and monthly up to 48 weeks. At each visit the infants were presented with their mother, a female stranger, and a rattle puppet that were alternately active and passive. Each condition lasted 60 s. The results showed that by 4 months of age the infants began to differentiate, in the proportion of time they looked, smiled, and vocalized, between people and the toy. They did not discriminate, however, between mother and female stranger and between the active and passive adults until the second half of the first year. In particular, whereas normal infants usually show distress toward passive or “still-face” adults, the infants in this study continued to vocalize, at times even with smiling faces. The implications of these atypical aspects of the social development of infants with Down syndrome for their subsequent nonverbal communicative development are discussed. |