A cross-sectional analysis of executive function in Down syndrome from 2 to 35 years

Background Previous research has indicated a unique profile of executive function (EF) in children and adolescents with Down syndrome (DS). However, there is a paucity of research on EF in adults with DS. This study aimed to gain a broader understanding of strengths and weaknesses in EF in DS from 2 to 35 years. Method Parents of 112 individuals with DS between 2 and 35 years participated in this study. Parents either completed the Behaviour Rating Inventory of Executive Function - for individuals 6+ years -or the Behaviour Rating Inventory of Executive Function Preschool Version - for children 2-5 years. Results Results suggest not only overall difficulties but also patterns of strength and weakness within EF for individuals with DS. For the 2 to 5-year-old group, emotional control and shift were relative strengths, planning/organisation and inhibit were intermediate skills, and working memory was a relative weakness. For the 6 to 18-year-old group, emotional control and organisation of materials were relative strengths, inhibit and initiate were intermediate skills, and working memory, monitor, planning/organisation, and shift were relative weaknesses. Most abilities were consistent from 2 to 18 years, except shift, which decreased in preadolescence before beginning to recover in adolescence. Across the full age range (2-35 years), composite scores indicated quadratic trends in inhibit, working memory, and planning/organisation, and a cubic trend in shift, with EF abilities generally declining in middle childhood before recovering in adulthood. Conclusions This study extends previous research on EF in DS by providing an initial description of EF profiles across the lifespan. More longitudinal and behavioural research is needed to further characterise the development of EF in DS.