The Role of Executive Function on Adaptive Behavior Skills

Background:  

Adaptive behavior abilities are the real-world everyday skills needed for independent living and social functioning, and are often impaired in individuals with ASD, even in those without co-occurring intellectual disability (ID).  Impaired adaptive behavior skills have been shown to predict adult outcome over and above intellectual level, highlighting the critical importance for intervention in this area (Klinger et al., 2015 IMFAR panel presentation).  In order to better understand the cognitive factors that impact adaptive functioning, research by Pugliese et al. (2014) has documented weaknesses in executive function (EF) skills, particularly initiation, working memory, organization of materials, and mental flexibility were associated with more impaired adaptive functioning.

Objectives:  

The aim of the current study is to support and expand the previous work showing a relationship between EF and adaptive behavior in four ways:  1) using a different adaptive behavior measure, the Adaptive Behavior Assessment System (domains = Conceptual, Social, Practical) as most previous research has used the Vineland Adaptive Behavior Scales (domains = Communication, Daily Living, Socialization); 2) extending the age range across the lifespan to include both children and older adults; 3) including a measure of comorbid psychopathology; and 4) including a clinical non-ASD comparison group.

Methods:  

This IRB-approved study is a record review of diagnostic evaluations of a clinically-referred population ages 5-66 years seen at a university-affiliated, community-based outpatient clinic.  The ADOS-2 and experienced clinical judgment were used to determine ASD diagnosis, and the SRS-2 was used to describe ASD symptom severity.  A standardized age-appropriate IQ measure was also administered.  EF skills were assessed by parent/teacher/informant report on the BRIEF.  The Achenbach scales for children and adults were used to assess co-occurring psychopathology. 

Results:  

Data collection and analyses are ongoing with a total anticipated n = 80-100.  Current n = 46; children ages 5-18 (n=25) and adults ages 19-66 (n=21) with Full Scale IQ ranging from 57-138 (8% diagnosed with ID).  60% met ASD criteria while 40% received other diagnoses instead (e.g., anxiety, depression or ADHD).  Preliminary analyses show a significant correlation between adaptive behavior composite and overall EF (r = -.71, p = .001) for those with ASD.  In contrast, in the clinical non-ASD group, this relationship was not significant despite also having low adaptive and EF scores (p’s > .29).  Hierarchical regressions will be run to examine the contributions of age, IQ, EF, and comorbid psychopathology to adaptive behavior.  Analyses for individual subgroups will be performed including stratifications across age.

Conclusions:  

Preliminary data show relationship between EF and adaptive behavior skills is particularly important in ASD as compared to other developmental and psychiatric disorders. A better understanding of the cognitive and emotional processes that contribute to adaptive behavior can inform interventions that will likely lead to a better outcome for individuals with ASD. Intervention techniques targeting EF skills look promising.  One such strategy is Structured TEACCHing, an evidence-based intervention framework that provides supports for deficits in several aspects of EF skills.