Are Executive Dysfunctions Relevant for the Autism-Specific Cognitive Profile?

Abstract

Executive functions (EF) have been shown to be important for the understanding of Autism Spectrum Disorder (ASD), but dysfunctions of EF are not autism-specific. The specific role of EF in ASD, its relationship to core autism characteristics, such as mentalizing, needs to be explored. Medline- and PsychINFO databases were searched for studies published between 1990 and 2020 that included measures of EF in ASD and typically developing control persons (TD) in combination with either Theory of Mind (ToM) or Weak Central Coherence (WCC) tasks. A pre-registered meta-analysis and cross-study regression was performed including a total of 42 studies (ASD n = 1,546, TD n = 1,206). Results were reported according to PRISMA guidelines. In all cognitive domains, the ASD group showed significantly reduced performance. Importantly, EF subdomains and ToM were not significantly correlated. This finding rules out a significant association between EF subdomains and ToM and questions the relevance of EF dysfunctions for the autism-specific feature of reduced mentalizing.

Keywords: autism (ASD); cognitive profile; executive function; theory of mind; weak central coherence.

FIGURE 1

Funnel plot of studies comparing Executive Function performance between ASD and TD. SMD, standard mean difference (Effect Size); SE, standard error; EF1, inhibition; EF2, working memory; EF3, flexibility; EF4, planning. Positive effect sizes indicate superior performance in ASD. The solid vertical line indicates the estimate for the population effect size.

FIGURE 2

Funnel plot for 11 studies comparing Central Coherence performance between ASD and TD. SMD, standard mean difference (effect size); SE, standard error. Positive effect sizes indicate superior performance in ASD. The solid vertical line indicates the estimate for the population effect size.

FIGURE 3

Funnel plot–theory of mind funnel plot for 26 studies comparing theory of mind performance between ASD and TD. SMD, standard mean difference (effect size); SE, standard error. Positive effect sizes indicate superior performance in ASD. The solid vertical line indicates the estimate for the population effect size.

FIGURE 4

PRISMA flowchart.

FIGURE 5

Forest plot–executive function: subgroup analysis of EF domains. Results show medium effect size measures for all EF subtypes observed. Graphical explanations: horizontal lines present 95% confidence Interval of the effect sizes for each study; green dot: hedges‘g; diamond shape: overall effect size.