Systematic review of cognitive biases in autism spectrum disorders: A neuropsychological framework towards an understanding of the high prevalence of co-occurring depression

•The first systematic review examining cognitive biases in individuals with ASD.•Results show no differences between groups, or less negative bias in individuals with ASD.•Theory of Mind and developmental age may partially have influenced the results.•Only a few studies consider the role of depressive and/or anxiety symptoms.•Cognitive biases may not explain the high prevalence of depression in ASD, more research specifically designed for ASD symptomatology is needed. Cognitive theories of major depressive disorder (MDD) assume that cognitive biases engender and maintain depressive symptoms. Given the higher prevalence of MDD in autism spectrum disorders (ASD) than in the general population, we performed a structured review of the empirical literature on cognitive biases in ASD to examine the possible role of biases in the increased cognitive vulnerability for MDD. We reviewed the recent literature on cognitive biases in individuals with ASD. Literature searches were conducted by using the databases PubMed and PsycInfo consistent with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. The 31 identified studies meeting our inclusion criteria were evaluated for quality using a modified version of the Systematic Assessment of Quality in Observational Research (SAQOR) rating system. The results show that half of the studies included did not find differences in cognitive biases in individuals with ASD compared to controls. In the studies that did establish differences in cognitive bias, individuals with ASD were reported to show less pronounced negative biases. A closer inspection reveals that Theory of Mind demands of the task and developmental age might partially have influenced these results. Importantly, most of the studies included did not control for symptoms of depression and/or anxiety. Although, based on the current literature, differential cognitive biases may not be a marker for MDD in ASD, more research is needed taking specific potential confounders, and distorting influences into account.