Executive Function and the Severity of Autism Symptoms and Associated Behaviors in Young Children with Autism Spectrum Disorder

Background: Although research has shown that individuals with autism spectrum disorder (ASD) evidence impairments in executive functioning (EF) (Demetriou et al., 2018), less is known about the association with other aspects of functioning in children, including language, adaptive behavior, and challenging behaviors. Furthermore, little is known about the relationship between EF and attentional skills in ASD. However, previous eye tracking (ET) studies have demonstrated that, when shown a dynamic video containing social and nonsocial stimuli, children with ASD spend less time attending to stimuli compared to typically developing children (Chawarska, Macari, & Shic, 2012).

Objectives: We examined the relationship between EF and core autism symptoms, language, adaptive behavior, challenging behaviors, and attention assessed via ET in young children with ASD.

Methods: 176 children with ASD (140 males; ages 2-8) participated in a clinical trial; ADOS-2 and ADI-R confirmed diagnosis. At baseline, participants completed the Expressive One-Word Picture Vocabulary Test, Fourth Edition (EOWPVT-4) and watched a 3-minute video including social and toy stimuli; gaze was monitored via ET. Sixteen participants were excluded for non-compliance and calibration failures, n = 160. Caregivers completed the Behavior Rating Inventory of Executive Function (BRIEF) or BRIEF-Preschool (BRIEF-P; participants under age 5), PDD Behavior Inventory (PDDBI), and Aberrant Behavior Checklist – Community (ABC-C) questionnaires, and Vineland Adaptive Behavior Scales, Third Edition (VABS-3) interview. BRIEF/BRIEF-P analyses included comparison of overlapping scales: Inhibit, Shift, Emotional Control, Working Memory, and Plan/Organize.

Results: Greater EF impairment, across all BRIEF scales, was associated with more severe autism symptoms, as reflected in the PDDBI Autism Composite score. Furthermore, greater EF impairments on all five BRIEF scales were associated with more severe symptoms on PDDBI Approach-Withdrawal subscales (Sensory/Perceptual Approach Behaviors, Ritualisms/Resistance to Change, Social Pragmatic Problems, Semantic/Pragmatic Problems, Arousal Regulation Problems, Specific Fears, and Aggressiveness; correlations ranging from r=.21 to r=.64, all p<.01). Greater EF impairments were also associated with increased challenging behaviors (ABC-C composite and all subscales: Irritability, Lethargy, Stereotypy, Hyperactivity, and Inappropriate Speech; correlations ranging from r=.42 to r=.54, all p<.03). Examining language, only the BRIEF scales measuring Inhibition and Working Memory were associated with less expressive vocabulary (EOWPVT-4 raw score). Greater EF impairments were associated with less developed adaptive skills on the VABS-3 Adaptive Behavior Composite, Communication Domain, and Daily Living Skills Domain. Finally, ET data revealed that greater proportion of time looking at media was positively associated with better EF in the areas of Emotional Control, Working Memory, and Plan/Organize.

Conclusions: Results suggest executive dysfunction, including challenges with inhibiting, shifting, emotional control, working memory, and planning/organizing, is associated with increased autism severity and challenging behaviors, and decreased expressive language and adaptive skills. Further, results indicate better EF in emotional control, working memory, and planning/organization is associated with more time visually attending to a dynamic video containing both social and non-social stimuli. Taken together, these results suggest that EF skills are closely linked to a wide range of behaviors in young children with ASD. As such, interventions that address EF skills may lead to improvements in other behavioral domains.