27949
Childhood Executive Function Predicts Later Adaptive Functioning and Autistic Features: A 12-Year Longitudinal Study
Long-term follow-up studies show that the developmental outcomes of autistic individuals are highly variable, even for individuals at the more able end of the autism spectrum. While some cognitively-able individuals go on to live independently and obtain qualifications, the majority fail to achieve independence, to attain full-time employment or to enjoy friendships. Explaining this variability is of critical importance: to discover why developments take place in some areas and not in others, and especially in some individuals and not in others.
Objectives:
This study sought to test the potential sources, namely theory of mind (ToM) and executive function (EF), of the variability in developmental outcomes in a cohort of autistic children assessed at two follow-up time-points, 3 years (Time 2) and 12 years (Time 3) after initial intake (Time 1).
Methods:
Thirty-seven autistic children (4 girls) were assessed on two key components of EF (planning and cognitive flexibility) and on a battery of ToM tasks (1st- and 2nd-order false-belief understanding) at Time 1 (M age = 5 years; 7 months) and Time 2 (M = 8 years; 4 months), as well as a measure of autistic features (ADOS-G). Of these 37 participants, 28 (2 girls) were assessed again at Time 3, 12 years later (M age = 17 years; 7 months), in terms of their adaptive behaviour (Vineland Adaptive Behaviour Scales – 2nd edition) and core autistic features (ADOS-2).
Results:
At Time 2 (3-year follow-up), early EF skills were longitudinally predictive of change in children’s ToM test performance, independent of age, language, nonverbal intelligence, and early ToM skills. Predictive relations in the opposite direction were not significant. Individual differences in early EF but not ToM skills also predicted variation in children’s social communication and repetitive behaviors and interests at the 3-year follow-up. At Time 3 (12-year follow-up), early EF and ToM skills predicted significant variance in autistic adolescents’ autistic features (ADOS severity scores) but only early EF skills predicted unique variance in young people’s adaptive behaviour at the 12-year follow-up.
Conclusions:
These longitudinal findings clearly demonstrate that EF measured in early childhood has predictive power: it uniquely predicts autistic children’s developing ToM and their behavioural features 3 years later, and their behavioural outcomes (autistic features, everyday adaptive functioning) 12 years later. Together, these findings provide compelling reasons to suggest that individual differences in the developmental trajectories of autistic children’s EF skills might well explain some of the variability in children's functional outcomes, both in the shorter term and in the longer term, and underscores their importance as a key target for early intervention. -p