A Transdiagnostic Profile of Executive Function in Children with Neurodevelopmental Conditions

Abstract

Executive functioning (EF) encompasses a diverse range of higher-order cognitive processes critical for goal-oriented behaviour, including but not limited to planning, working memory, attention and inhibition. EF impairments are prevalent across various neurodevelopmental conditions (NDCs), such as Autism (ASD), Attention-deficit/hyperactivity disorder (ADHD), and Specific Learning Disorder (SLD), contributing to social, behavioural, and mental health challenges. This thesis aims to advance the transdiagnostic understanding of EF development in children with NDCs, specifically ASD, ADHD and SLD. The first study presents a systematic review and metaanalysis of EF across NDCs, comparing EF delays between these conditions and neurotypical children. The second study evaluates informant-reported EF in children with ASD, ADHD, and SLD, examining how EF profiles shift with increasing comorbidities. The third study explores the relationship between parental evaluations of children’s developmental functioning and EF outcomes, focusing on how these evaluations relate to reported EF delays and strengths. The meta-analysis revealed significant EF delays across NDCs, with a moderate delay compared to controls. Specific conditions, such as ADHD, showed more pronounced delays in certain EF domains, including working memory, response inhibition, and attention. The second study demonstrated that EF delays intensify with additional comorbidities, particularly when ASD is present. The third study found that EF delays were linked to common concerns like behaviour and social/play issues, as reported by caregivers, with interesting findings for reported childhood strengths. This research highlights the transdiagnostic nature of EF delays in NDCs and suggests that EF could inform support strategies for children with NDCs. The thesis concludes with discussions on future research directions and theoretical implications.