Executive function profiles of preschool children with autism spectrum disorder and attention‐deficit/hyperactivity disorder: A systematic review

Abstract

Background Autism Spectrum Disorder (ASD) and Attention‐Deficit/Hyperactivity Disorder (ADHD) are both associated with differences in Executive Functioning (EF). There is lack of clarity around the specificity or overlap of EF differences in early childhood when both disorders are first emerging. Method This systematic review aims to delineate preschool EF profiles by examining studies comparing the EF profiles of children with and without ASD or ADHD. Five electronic databases were systematically searched (last search in May 2022) to identify published, quantitative studies of global and specific EF (Inhibition, Shifting, Working Memory (WM), Planning and Attentional Control), comparing children aged 2‐6 with a diagnosis of ASD or ADHD to peers without ASD or ADHD. Results Thirty‐one empirical studies (10 ADHD and 21 ASD studies) met criteria for inclusion. EF profiles in preschool ASD were characterised by consistent Shifting, and, in most cases, Inhibition impairments. ADHD studies consistently reported impairments in Inhibition and Planning, and in most cases WM. Findings with regards to sustained Attention and Shifting in ADHD and WM and Planning in ASD were mixed. Conclusions Overall, current evidence indicates overlap but also some specificity in EF impairments in preschool ASD and ADHD. There were differences in the degree to which individual domains were impaired, with Shifting more consistently impaired in ASD, and Inhibition, WM and Planning in ADHD. Methodological issues and differences in methods of outcome measurement could potentially underlie mixed findings, as informant‐based measures revealed more robust EF impairments than laboratory‐based tasks.

Variation in problem-solving success amongst children with and without a family history of ADHD

“…Cognitive flexibility difficulties are not evident in all contexts for all autistic people (Leung & Zakzanis, 2014), and may be moderated by general intelligence and co-occurring conditions (Kalbfleisch & Loughan, 2012;Kenworthy, Yerys, Anthony, & Wallace, 2008). Nevertheless, difficulties with cognitive flexibility are widely apparent amongst autistic pre-schoolers (Christoforou, Jones, White, & Charman, 2023). Regarding problem-solving specifically, autistic children show lower generativity (Lai et al, 2017), and higher perseveration: in a parent-report study the item "Tries the same approach to a problem over and over even when it does not work," was endorsed by more than two-thirds of parents of autistic children (Granader et al, 2014).…”

Slower pace in early walking onset is related to communication, motor skills, and adaptive function in autistic toddlers

“…It is possible that differences in executive function (EF) may be associated with the gait differences observed in the autism group. There are known to be EF deficits in individuals with autism and gait is dependent on both motor and EF processes (Christoforou et al, 2023; Yogev‐Seligmann et al, 2008). Motor studies in adults and older children have found altered spatiotemporal variables of gait, such as slowing of gait speed, when measured while participants conduct concurrent EF tasks (Möhring et al, 2020; Rabaglietti et al, 2019).…”

How to advance the understanding of multimorbidity in neurodevelopmental disorders using longitudinal research?

“…The publication by Christoforou et al. ( 2023 ) presents results of a carefully conducted systematic review of studies examining preschool executive functioning in children with and without autism or ADHD. The identified studies suggest that pre‐schoolers with autism or ADHD demonstrate robust impairments in global executive functioning.…”