Main Article Content
Executive functioning, FASD, meta-analysis
Background / Objectives:
Extant research consistently identifies executive functions (EF) as a central impairment associated with Fetal Alcohol Spectrum Disorders (FASD). Despite this, heterogeneity exists regard ing the strength of the association between FASD and EF, and findings have not yet been quantitatively synthesized. Further, it remains unclear whether EF deficits differ between FASD and other clinical populations.
This meta -analysis included 4 6 studies examining the relation between FASD and EF. All studies compared children and adolescents with a diagnosis of FASD to healthy control participants. A subset of 13 studies compared FASD to ADHD participants. Following Miyake Emerson, Witzki, and Howerter’s (2000) model of EF, working memory, inhibition, and set shifting were the EF examined.
When compared to healthy controls, children with FASD demonstrated significant deficits across these EF ( d = 0.67 [0.56, 0.77]). Magnitude of the effe ct differed by type of EF, with working memory ( d = 0.67 [0.50, 0.85]) and inhibition ( d = 0.65 [0.50, 0.80]) yielding medium effects and set shifting yielding a large effect ( d = 0.84 [0.70, 0.99]). Several characteristics of the sample, nature of prenatal exposure, and EF methodology significantly moderated these results. A secondary meta -analysis of studies examining FASD and ADHD suggested that the relation between weaknesses in EF and FASD is stronger than that found for children with ADHD only ( d = 0. 25 [0.17, 0.34]). Interestingly, only IQ emerged as a significant moderator, such that FASD samples with lower IQ had greater EF deficits compared to ADHD samples.
Conclusions / Discussion:
These findings support the notion that FASD is broadly related with EF deficits, though important nuances exist within these associations. These deficits are greater than those with ADHD, particularly for children who present with low IQ. Research and clinical implications will be discussed with regards to the neurodeve lopmental considerations within FASD populations.