The association between the social and communication elements of autism, and repetitive/restrictive behaviours and activities: A review of the literature

Research continues to try and pinpoint the etiological role of particular genes and brain structure in autistic spectrum disorder (ASD), but despite a host of biological, genetic and neuropsychological research, the symptom profile of pervasive developmental disorders (PDDs) are not yet linked to etiological theory. Debate continues around whether or not there is one single dimension that incorporates the three criteria domains of social difficulties, communication deficits and repetitive or restrictive interests and behaviours as a unitary ‘ASD’ concept, or whether PDD as they are currently described represent the co-occurence of separate sub-domains of developmental difficulties. Although the three criteria need to be met for a diagnosis of PDD to be made, the association between them remains unclear. This review highlights that the majority of the literature that looks at the triad of impairments suggests the symptom structure does not match that proposed by diagnostic manuals, and that the triad may no longer fit as the best way to conceptualise ASD.

► Autistic spectrum disorders (ASD) have been conceptualised in the past as a triad of impairments.
► Most of the reviewed literature suggests the symptom structure does not match the triad of impairments.
► The review suggests social and communication deficits might best be considered together as a single domain.
► Similarly repetitive/restrictive behaviours and activities are indicated as comprising a separate symptom domain.
► The review suggests that the triad of impairments may no longer fit as the best way to conceptualise ASD.