Previous research has established that individuals with autism spectrum disorders (ASD) have higher rates of unusual responses to sensory stimuli than the typical population. Differences in these behaviors between children with autism compared to children with other clinical populations have not been as consistent. Research in this area is limited by inconsistencies in definitions of what constitutes sensory behavior, differences in how behaviors are assessed, and how styles of responding are defined (e.g. hyper-responsivity versus sensory sensitivity).

The three studies included in this dissertation examined unusual sensory responses in children between the ages of 12 and 36 months who were at higher risk for having ASD. The first study examined the validity of using the Toddler Sensory Profile Questionnaire (TSP) to measure sensory behaviors in children with ASD by identifying items in the TSP that overlap with autism-specific behaviors and comparing performance on the TSP to other measures of sensory behavior. The goal of the second study was to compare the sensory behaviors of children with ASD to typically developing children and children with nonspectrum developmental disorders. In addition, the effect of individual characteristics, such as NVIQ, age, risk status and diagnosis, was examined. The third study examined the relationship between atypical sensory behavior and impairments in socialization by examining the relationship between scores on the TSP and socialization as measured by the Autism Diagnostic Observation Schedule (ADOS), The Autism Diagnostic Interview-Revised (ADI-R), and the Vineland Adaptive Behavior Interview (VABS).

Results support previous research that children with autism have higher rates of unusual sensory responses than typically developing peers. However, caution should be used when interpreting findings from studies that use the TSP as several TSP items were identified as autism-specific behaviors. NVIQ, age, and diagnosis were found to have an effect on sensory behavior, but the effect differed based on the sensory modality or style being addressed. Results of Study 3 indicated a relationship between sensory behaviors and socialization, specifically when socialization is measured by the ADI-R and the VABS. Implications of these findings and limitations of the studies and other research regarding sensory behaviors in children are discussed.