Autism is a common and often highly debilitating neurodevelopmental condition, whose core behavioral features are believed to be rooted in disrupted neurocognitive processes, including especially “executive function.” Researchers have predominantly focused upon understanding the putative causal relationship between difficulties in EF and autistic symptomatology. This paper suggests, however, that the effects of individual differences in EF should be more far-reaching, playing a significant part in the real-life outcomes of individuals with autism, including their social competence, everyday adaptive behavior, and academic achievement. It further considers the nature of the EF-outcome relationship, including the possible determinants of individual differences in EF, and makes several recommendations for future research. 1. Introduction Autism spectrum conditions (hereafter, “autism”) are a set of common, lifelong neurodevelopmental conditions that involve substantial heterogeneity at numerous levels, including etiology, neurobiology, cognition, and especially behavior. Long-term follow-up studies show that the developmental outcomes of autistic individuals are highly variable, even for individuals at the more intellectually able end of the autism spectrum. While some individuals go on to live independently and obtain qualifications, the majority fail to achieve independence, to attain full-time employment, or to enjoy friendships [1–5] (though see [6]). Explaining this variability is of critical import: to discover why developments take place in some areas and not in others, and especially in some individuals and not in others. Researchers have little understanding of the factors underpinning this heterogeneity, due in part to a dearth of longitudinal studies tracing the development of autism and to the preponderance of studies using a case-control design, focusing on group rather than on individual differences. This paper aims to address this limitation. It identifies one potential source of this variability, namely, autistic children’s emerging “executive function” (EF), those higher-order processes, closely associated with the prefrontal cortex, which are necessary for regulating and controlling behavior (see Table 1). Specifically, it suggests that individual differences in the growth trajectories of autistic children’s EF skills could explain some of the variability in children’s functional outcomes, including their social awareness, real-life adaptive behavior, and readiness to learn in school, both in the shorter term and in the longer term. Table
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