Electronic Thesis and Dissertation Repository


Master of Science




Stevenson, Ryan A.


The heterogenous expression of Autism Spectrum Disorder (ASD) complicates our etiological understanding of the disorder. By focusing on the most commonly-reported symptom of ASD, namely sensory processing dysfunction, this project attempts to determine the underlying factors of autism-related restricted interests and repetitive behaviours (RRBs). The specific aims of this project are to examine the relationship between sensory sensitivity and RRBs and to compare current questionnaire measures of sensory processing issues to more objective measures, specifically, a psychophysical behavioural task of visual sensitivity. A positive relationship was found between sensitivity and RRBs in both autistic children and their TD peers. Furthermore, both behavioural and self-reported sensitivity are related to and predict RRBs in TD adults. Overall, the results suggest that sensitivity is related to RRBs but that our current measures of sensory sensitivity, namely questionnaire measures, may not be measuring sensitivity per se, but instead measure sensory reactivity.