Joint engagement and the emergence of language in children with autism and Down syndrome

Abstract

Systematic longitudinal observations were made as typically developing toddlers and young children with autism and with Down syndrome interacted with their caregivers in order to document how joint engagement developed over a year-long period and how variations in joint engagement experiences predicted language outcome. Children with autism displayed a persistent deficit in coordinated joint attention; children with Down syndrome were significantly less able to infuse symbols into joint engagement. For all groups, variations in amount of symbol-infused supported joint engagement, a state in which the child attended to a shared object and to language but not actively to the partner, contributed to differences in expressive and receptive language outcome, over and above initial language capacity.

Figure 1

Mean engagement state percentages by diagnostic group. SJnt = non-symbol-infused supported, SJSI = symbol-infused supported, CJSI = symbol-infused coordinated, CJnt = non-symbol-infused coordinated, Obj = solitary object engagement, and Uneng = unengaged. Right-upward strips represent supported and right-downward stripes represent coordinated joint engagement; gray shaded stripes in the middle represent their overlap with symbol-infused joint engagement.

Figure 2

Engagement state trajectories for supported, symbol-infused, and coordinated joint engagement by diagnostic group. TD = typically developing, DS = Down syndrome, AU = autistic, N = 56, 28, and 20, respectively.