Parent Report of Executive Functioning in Individuals with a History of ASDs Who Have Achieved Optimal Outcomes

Background: A study is currently following children and adolescents who have a history of autism spectrum disorders (ASDs), but who no longer meet diagnostic criteria for such a disorder. These individuals have achieved social and language skills within the average range for their ages and receive little or no school support. Several recent studies suggest that this small subset of individuals, once diagnosed with ASDs, achieve "optimal outcomes" (OO, Sutera et al., 2007; Kelley, Naigles & Fein, 2010; Helt et al., 2008).

Objectives: This study examines parent report of executive functioning (EF) among children and adolescents who achieved OO. 

Methods:  Parents of 28 individuals who achieved OO completed the Behavior Rating Inventory of Executive Function (BRIEF) and their responses were compared to parent responses of 25 high-functioning individuals with a current ASD diagnosis (HFA), and 31 typically developing peers (TD). The BRIEF provides a Global Executive Composite score and measures eight domains of EF:  Inhibit, Shift, Emotional Control, Initiate, Working Memory, Organization of Materials, Monitor, and Planning and Organizing. Higher scores indicate greater degree of impairment and scores at or above 65 indicate potentially clinically significant executive dysfunction. The groups were matched on age (M=13.28), gender and nonverbal IQ; however the groups differed significantly on verbal IQ (M(HFA)=106.81, M(OO)=115.36, M(TD)=112.04, F=7.50, p<0.01).

Results:  Parent responses on the BRIEF indicated that the mean scores of the OO and TD groups did not fall in the clinically significant range on any of the subscales.  Although the Global Executive Composite score of the OO group was significantly higher than the TD group, it was still well within the average range (M(OO)=49.52, M(TD)=43.03).  The OO groups’ scores on the Inhibit, Emotional Control, and Working Memory subscales were also significantly higher than those of the TD group, but still fell in the average range.  Additionally, the OO group received significantly lower scores than the HFA group on the Global Executive Composite (M(OO)=49.52, M(HFA)=65.29) and on all of the subscales of the BRIEF.  Mean scores of the HFA group fell in the clinically significant range on the Shift and Monitor subscales.

Conclusions: Results of this study suggest that according to parent report the executive functioning in individuals who achieved OO is intact.  IQ-matched individuals in the TD group appeared to exhibit well developed EF, commensurate with their above-average IQs.  While the OO group scored solidly in the average range, their scores were lower than in the TD group, suggesting that the OO group does not have the above-average EF scores despite their high-average IQs. Performance in the HFA group suggested clinically significant deficits in their ability to switch from one activity to another and in their ability to monitor their performance.