Behavioural, Biopsychosocial, and Cognitive Models of Autism Spectrum Disorders

Abstract

(from the chapter) Autism spectrum disorder (ASD) comprises a range of developmental disorders including autistic disorder, Asperger's disorder, and pervasive developmental disorder not otherwise specified/atypical autism, each of which is characterized by a triad of impairments in social interaction, communication, and restricted, repetitive behaviours and interests (RRBIs). ASD is a behaviourally defined disorder with a biological basis. The behavioural definition and the (presumably forthcoming) identification of a set of genetic or neurobiological markers for ASD represent descriptive models of the disorder. Morton and Frith have argued that in order to develop a causal model of ASD, a third level of explanation-the cognitive or psychological level -is necessary to bridge the gap between the biological and behavioural levels. In other words, in order to understand the mechanisms by which genes and neurobiology influence behaviour, it is necessary to understand the cognitive processes that mediate that behaviour-there is arguably no direct link between biology and behaviour in ASD. For this reason, cognitive accounts are essential to our understanding of the disorder. This chapter reviews three of the most influential accounts (as well as some of their variants/alternatives) and their respective relationships to brain function and behaviour, in the spirit of the causal modelling approach. We will begin by describing the theory of mind hypothesis of ASD-a domain-specific, "social" account-and go on to discuss the executive dysfunction and weak central coherence hypotheses-domain-general, broadly "non-social" accounts. Evidence for and against each of the theories will be considered, as well as issues of universality, specificity, and relationships to ASD diagnostic features. The chapter concludes with a section considering future directions for cognitive explanations of ASD. (PsycINFO Database Record (c) 2015 APA, all rights reserved)