Attention and Executive Function As Predictors of Functional Impairments in Adolescents with Autism Spectrum Disorder

Background: Executive function (EF) and attention are two cognitive abilities that consist of the fundamental skills necessary for directing and maintaining focus, as well as goal- directed behaviour and problem solving.  Such abilities have been found to be critical for the development of functional outcomes such as social skills, academic achievement, and adaptive behaviour. The relationship of attention and EF with functional outcomes is relevant to clinical populations that show deficits in these abilities, such as individuals diagnosed with an autism spectrum disorder (ASD).  EF deficits are likely related to many of the commonly reported social, academic, and daily living impairments experienced by individuals with ASD. Clarification is needed regarding the link between these deficits and functional outcomes, especially with respect to adolescents.

Objectives: The current study aims to extend our understanding of these cognitive and functional deficits among adolescents with ASD. Firstly, this study investigates the nature of EF and attention deficits in adolescents with ASD as compared to typically developing (TD) controls.  Secondly, this study examines the association of EF and attention with functional outcomes in adolescents with ASD, as well as in TD controls.  Findings will help clarify the nature of the relationship between cognitive and functional deficits in adolescents with ASD.

Methods: We anticipate a sample of 60 adolescents (30 ASD and 30 TD), 12-18 years of age.  EF is assessed using five subtests from the Delis-Kaplan Executive Function System (DKEFS).  Attention is assessed using four custom attention tasks administered on the computer.  Academic ability is assessed using five subtests from the Woodcock-Johnson III Tests of Academic Achievement (WJ-III).  Social skills are assessed with the Social Skills Rating System (SSRS) parent report. Adaptive behaviour is assessed with the Vineland Adaptive Behaviour Scale-II (VABS-II) parent survey interview form.  Such a battery of assessments allows for cross-informant reports on cognitive and functional abilities.

Results: Preliminary results are based on a sample of 27 participants (6 ASD and 21 TD).  Independent samples Mann-Whitney U tests show that the ASD group scores lower than the TD group on a number of cognitive shifting EF tasks at trend level significance (ps < .07).  However the ASD group only scores lower on one measure of attention (p = .05).  Additionally, Pearson correlations reveal trend level correlations between cognitive shifting EF tasks and functional outcomes (ps < .06), as well as trend level correlations between many measures of attention and functional outcomes (ps < .07).  Marginally significant results suggest a trend towards significance once a larger sample is collected.

Conclusions: Preliminary findings indicate deficits in EF, academic ability, social skills, and daily living skills in adolescents with ASD. Additionally, lower EF and attention are correlated with higher levels of functional impairment for both ASD and TD groups. Findings will help clarify the nature of the relationship between cognitive and functional deficits in ASD. Insight into these issues may be beneficial for planning intervention and support for these individuals as they mature.