Relationship Between Atypical Sensory Behaviors and Socialization in Toddlers with Autism Spectrum Disorders

Background: Research has shown that while not unique to autism spectrum disorders (ASD), unusual responses to sensory stimuli are more common among individuals with ASD than among typically developing individuals or individuals with nonspectrum developmental delays.  While studies vary in terms of which sensory modalities and behaviors are examined, one of the most consistent findings is the increased rate of hyporesponsiveness to sensory stimuli among individuals with ASD.  In addition, one study found that hyporesponsiveness to social stimuli specifically differentiated the children with autism from PDD-NOS, suggesting that there may be a relationship between the increased social impairment in autism and atypical sensory responses.  Few studies, however, have examined the relationship between unusual sensory responses and the core characteristics of autism.  A relationship between unusual sensory symptoms and impairments in socialization could be hypothesized based on the results of previous studies that suggest a correlation between increased autism severity and increases in unusual sensory responses as well as research in the field of personality psychology, which has found connections between sensory response style and extroversion/introversion. 

Objectives: The aim of the present study was to examine the relationship between atypical sensory responses and socialization among a group of toddlers with ASD, taking into consideration differences in NVIQ, age, and diagnosis.  

Methods: Forty-nine participants were assessed multiple times between the ages of 12 months and 36 months.  The average number of assessments was 3.8, with a range of 1-15.  The Toddler Sensory Profile (TSP) was used to measure responses to sensory stimuli and the Autism Diagnostic Observation Schedule (ADOS), Autism Diagnostic Interview-Revised (ADI-R), and Vineland Adaptive Behavior Interview were used to assess socialization.  Effect of unusual sensory responses on socialization was examined using general linear modeling and linear mixed modeling.   

Results: Preliminary analyses indicated that there were significant correlations between ADOS Social Affect domain scores and TSP sensory scores.  However, after controlling for age, NVIQ, and diagnosis, there was no relationship between the ADOS Social Affect algorithm scores and scores on the TSP.  There was a significant effect of Low Registration, Sensory Sensitivity and Sensation Avoiding on ADI-R Reciprocal Social Interaction Domain scores and Vineland Socialization Domain Standard Scores, even after controlling for NVIQ, age, and diagnosis. 

Conclusions: Results indicated that there is a relationship between sensory behaviors and socialization, however, the effect that atypical sensory behavior has on socialization is moderated by whether or not NVIQ and diagnosis are controlled for and how socialization is measured.