Profiles and trajectories of executive functioning in young children with Down syndrome.

Abstract

Language acquisition strongly predicts executive functioning (EF) in early childhood in typical development and in children with Down syndrome (DS). Both language and EF are critical contributors to later positive social and academic outcomes yet are often areas of concern in children with DS. Despite the wider availability of interventions targeting language development in DS, no efforts have been made to understand how these interventions may influence the development of EF in this population. This study examined secondary data from 76 preschoolers with DS collected as part of a randomised waitlist control trial of an early social communication intervention (JASPER-EMT). Children's EF skills were measured using the BRIEF-P, at three timepoints over 6months. Linear regression was used to examine the baseline relationship between child characteristics and the three indices of the BRIEF-P: Emergent Metacognition, Flexibility and Inhibitory Self-Control. Linear mixed effects models were used to estimate change across the three indices of the BRIEF-P and whether that change was moderated by treatment. Children in this sample exhibited an uneven profile of EF at baseline, with relative strengths in the Flexibility Index and the Inhibitory Self-Control Index, and relative weaknesses in the Emerging Metacognition Index. Chronological age was associated with all indices at baseline (all P<0.05). Children in the intervention group exhibited improvements in the Flexibility Index from entry to exit (3months later) compared with the control, although this treatment effect did not maintain at the follow up at 6months. Baseline EF profiles of children were consistent with findings of other studies with children with DS. Longitudinal findings suggest that behavioural interventions targeting language may have positive collateral effects on certain EF skills, however these effects may be transitory without ongoing support. These findings illustrate both the need for further exploration of the impact of early language interventions on EF abilities and the malleability of certain EF domains in young children with DS.