Understanding Individual Differences in Autism Spectrum Disorder Through a Trait-Based Approach: A Literature Review

Abstract

Autism Spectrum Disorder (ASD) shows substantial heterogeneity in social communication, sensory processing, and cognitive functioning that categorical diagnostic systems struggle to capture. This review examines the extent to which a trait-based approach, conceptualising autistic characteristics as continuously distributed dimensions, accounts for individual differences in ASD. It traces the historical and psychometric basis of the trait perspective and integrates behavioural-genetic and neuroimaging evidence across three domains: social communication, sensory processing, and cognitive flexibility. It then considers domain-targeted interventions addressing these dimensions, before critically examining limitations concerning social camouflaging, environmental influences on trait expression, and developmental change. The review concludes that the trait approach offers considerable explanatory and clinical value, but functions best as a complement to, rather than a replacement for, categorical diagnosis, with future research needing to test trait-informed intervention models directly.