Embedded Figures Test Performance in the Broader Autism Phenotype: A Meta-analysis

Abstract

People with autism show superior performance to controls on the Embedded Figures Test (EFT). However, studies examining the relationship between autistic-like traits and EFT performance in neurotypical individuals have yielded inconsistent findings. To examine the inconsistency, a meta-analysis was conducted of studies that (a) compared high and low Autism-Spectrum Quotient (AQ) groups, and (b) treated AQ as a continuous variable. Outcomes are consistent with superior visual search forming part of the broader autism phenotype, but in existing literature, this is evident only when comparing extreme groups. Reanalysis of data from previous studies suggests findings are unlikely to be driven by a small number of high scorers. Monte Carlo simulations are used to illustrate the effect of methodological differences on results.

Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias

“…As already noted, abnormal biases in local/global visual processing have been reported in individuals diagnosed with an ASD (e.g., Plaisted et al, 1999; Spencer et al, 2000; Pellicano et al, 2005; Bolte et al, 2007) and have also been established in neurotypical populations with higher autism-like characteristics (e.g., Grinter et al, 2009; Almeida et al, 2010; Crewther and Crewther, 2014; Crewther et al, 2015; Cribb et al, 2016). Nevertheless, although it is suggestive, as Gregory and Plaisted-Grant (2013) have argued, it cannot be assumed that the same underlying mechanism can explain a given perceptual abnormality in clinical and non-clinical groups.…”

Evidence for a Broad Autism Phenotype

“…Also, Figure-Ground visual skill scores are positively correlated with (not AQ-measured) self-reported autism-like social features (DiCriscio and Troiani 2017). Metaanalytic results also showed superior visual search within the broad autism phenotype (Cribb et al 2016). Furthermore, TD individuals with more self-reported autistic traits showed a Flanker task interference pattern similar to that of diagnosed individuals, having stronger interference at higher perceptual loads (Bayliss and Kritikos 2011;Remington et al 2009).…”

“…Instead of investigating whether someone with a certain AQ score has less problems in social functioning than someone with a somewhat higher AQ score, it is examined whether someone with an extremely low AQ score differs from someone with an extremely high score, which is not what the autism spectrum hypothesis encompasses. In case of visuospatial ability, it has already been demonstrated that in the existing literature, the superior visuospatial skills found in individuals with ASD are only evident across the broad spectrum when comparing extreme groups of TD individuals (Cribb et al 2016). This indicates that positive findings from studies using extremes do not necessarily replicate when examining a true broad spectrum consisting of a natural range of AQ scores.…”

“…This implies that a high-AQ group might not only quantitatively but also qualitatively differ from other individuals across the spectrum, thereby in fact disproving instead of supporting a broad autism phenotype. However, it must be acknowledged that reanalysis of the literature on visuospatial ability shows that removing individuals scoring above a clinical cut-off does not change the pattern of results, with high-AQ individuals and low-AQ individuals still significantly differing from each other (Cribb et al 2016). It is, however, not clear whether this would also be the case for e.g.…”

“…With respect to studies examining the broad phenotype for social functioning, one study used both a regression and an extreme group approach (Jobe and White 2007), and three out of the seven discussed studies exclusively selected participants from the extreme ends of the distribution (Jameel et al 2014(Jameel et al , 2015Poljac et al 2013). This was also the case for 4 of the 10 cognitive, visuospatial, executive and motor function studies mentioned (Grinter et al 2009;Kunihira et al 2006;Poljac et al 2012;Stewart et al 2009) and for 9 of the 12 studies discussed in a meta-analysis specifically focused on visuospatial ability (Cribb et al 2016). Instead of using regression or a median split to include all participants, most of these studies examining the broad autism phenotype recruited several hundred participants and used extreme cut-offs or the upper and lower percentiles of these large databases to select TD individuals with respectively very high and very low AQ scores.…”