Executive Functioning in High-functioning Children with Autism

Abstract

Executive functioning was investigated in 34 children (24 boys and 10 girls) with developmental language disorder (DLD) and 21 children (18 boys and 3 girls) with high-functioning autistic disorder (HAD) matched on Full Scale IQ, Nonverbal IQ, age (mean age 9 year, 1 month), and SES. The DLD group had a Verbal IQ that was 10 points higher than the HAD group. These children were given the Wisconsin Card Sorting Test (WCST), the Mazes subtest from the WISC-R, the Underlining test, and the Rapid Automatized Naming test. In addition, these children were given the Vineland Scales of Adaptive Functioning and the Wing Diagnostic Symptom Checklist in order to assess severity of autistic symptomatology. Results indicated that the only significant difference between the two groups on the cognitive tasks was perseverative errors on the WCST; there was no significant difference on total number of categories achieved or total number of errors on the WCST or on the other executive function measures. There was also significant overlap in the scores between the two groups and the difference in perseverative errors was no longer significant when Verbal IQ was partialled out. Executive functioning was strongly related to all IQ variables in the DLD group and particularly related to Verbal IQ in the HAD group. Although there was a relationship in the HAD group between executive functioning and adaptive functioning, as well as between executive functioning and autistic symptomatology, these relationships were generally no longer significant in the HAD group after the variance due to Verbal IQ was accounted for. The results are interpreted to indicate that although impaired executive functioning is a commonly associated feature of autism, it is not universal in autism and is unlikely to cause autistic behaviors or deficits in adaptive function.

Cognitive Set Shifting Deficits and Their Relationship to Repetitive Behaviors in Autism Spectrum Disorder

“…For IQ testing, participants 18 years of age and younger completed the Differential Ability Scales-2nd edition (DAS-II; Elliot 2007) (ASD = 37; Control = 31) or the Wechsler Abbreviated Scale of Intelligence (WASI; Wechsler 1999) (ASD = 9; Control = 9), and participants over 18 years of age completed the WASI (ASD = 14, Control = 15). While verbal IQ (VIQ) has been previously shown to be associated with executive function impairments in ASD (Bishop and Norbury 2005; Liss et al 2001; Pellicano 2007), we matched groups on NVIQ because the PCET places limited verbal demands on participants. Further, many individuals with ASD have more severe deficits in verbal compared to nonverbal IQ, suggesting that matching individuals with ASD and typically developing controls on verbal IQ may result in an ASD sample that is less representative of the broader population (Munson et al 2008).…”

The orbitofrontal–amygdala circuit and self-regulation of social–emotional behavior in autism

“…However, there is also evidence that executive function deficits are not specific to autism (e.g. Baron-Cohen and Robertson, 1995;Griffith et al, 1999;Ozonoff, 1997;Pennington et al, 1997;Sergeant et al, 2002) and that they may be reduced or absent in the highest functioning individuals, especially those with Asperger syndrome (Liss et al, 2001;Rinehart et al, 2001). Thus, even though executive function deficits are present in persons with autism, they are, by themselves, probably insufficient to account for the behavioral manifestations of autism, apart from performance on ToM and some other cognitive tasks.…”

Brief Report: Impaired Flexible Item Selection Task (FIST) in School-Age Children with Autism Spectrum Disorders

“…Cognitive flexibility is impaired in adults and children with autism spectrum disorders (ASD) when performance is measured in the laboratory (Lopez, Lincoln, Ozonoff, & Lai, 2005; Maes, Eling, Wezenberg, Vissers, & Kan, 2010; Ozonoff et al, 2004; Schmitz et al, 2006; Solomon, Ozonoff, Cummings, & Carter, 2008; Solomon et al, 2008; South, Ozonoff, & McMahon, 2007; Yerys et al, 2009; but see Goldberg et al, 2005; Happé, Booth, Charlton, & Hughes, 2006; Liss et al, 2001; Poljac et al, 2010). Furthermore, parents' reports of cognitive flexibility in everyday settings suggest significant impairments in children with ASD (Boyd, McBee, Holtzclaw, Baranek, & Bodfish, 2009; Gioia, Isquith, Kenworthy, & Barton, 2002; Kenworthy, Black, Harrison, Della Rosa, & Wallace, 2009).…”

“…F. Pennington & Ozonoff, 1996; Sergeant, Geurts, & Oosterlaan, 2002), these findings have significant limitations. Having a computer providing feedback has yielded better inductive reasoning cognitive flexibility performance in ASD relative to controls than human feedback (Ozonoff, 1995; Pascualvaca, Fantie, Papageorgiou, & Mirsky, 1998), and co-varying verbal intelligence even when ASD and controls are matched on this variable has been shown to eliminate group differences on inductive reasoning tasks (Liss et al, 2001). The simplified format of explicit tasks may explain why there is less consistency in identifying impairments for individuals with ASD (Bíró & Russell, 2001; Schmitz et al, 2006; Solomon et al, 2008, 2009).…”