Repetitive behaviors are observed in autism spectrum disorder and obsessive-compulsive disorder. Clinically, obsessive-compulsive disorder obsessions are thought to drive repetitive or ritualistic behavior designed to neutralize subjective distress, while restricted and repetitive behaviors are theorized to be reward- or sensory-driven. Both…

Neurofibromatosis Type 1 (NF1) is a common autosomal dominant single-gene disorder, in which the co-occurrence of autism spectrum disorder (ASD) has attracted considerable research interest recently with prevalence estimates of 21-40%. However, detailed characterization of the ASD behavioral phenotype in NF1 is still lacking. This study…

Background: There is a need for a more accurate characterisation of higher level restricted and repetitive behaviour (RRB) in autism spectrum disorder (ASD), including why it might be considered problematic and events associated with its occurrence. Method: We selected one form of higher level RRB--arranging and ordering--that was rated as severe…

Objective: To use confirmatory factor analysis to test the construct validity of the proposed "DSM-5" symptom model of autism spectrum disorder (ASD), in comparison to alternative models, including that described in "DSM-IV-TR." Method: Participants were 708 verbal children and young persons (mean age, 9.5 years) with mild to severe autistic…