Objective: Although several studies have investigated developmental trajectories of executive functioning (EF) in individuals with autism spectrum disorders (ASD) using lab-based tasks, no study to date has directly measured how EF skills in everyday settings vary at different ages. The current study seeks to extend prior work by evaluating age-related differences in parent-reported EF problems during childhood and adolescence in a large cross-sectional cohort of children with ASD.
Method: Children (N = 185) with an ASD without intellectual disability participated in the study. Participants were divided into four groups based on age (5-7, 8-10, 11-13, and 14-18-year-olds). The four age groups did not differ in IQ, sex ratio, or autism symptoms.
Results: There were significant age effects (i.e., worsening scores with increasing age) in three of G. A. Gioia, P. K. Isquith, S. Guy, and L. Kenworthy's (2000) BRIEF: Behavior Rating Inventory of Executive Function, Odessa, FL, Psychological Assessment Resources scale scores: Initiate (p = .007), working memory (p = .003), and organization of materials (p = .023). In addition, analysis of the BRIEF scale profile revealed that, although multiple scales were elevated, the shift scale showed the greatest problems in both the youngest and oldest age cohorts.
Conclusions: Older children with ASD show greater EF problems compared with the normative sample than younger children with ASD. Specifically, there is a widening divergence from the normative sample in metacognitive executive abilities in children with ASD as they age. This, in combination with significant, albeit more stable, impairments in flexibility, has implications for the challenges faced by high-functioning individuals with ASD as they attempt to enter mainstream work and social environments.