The Relationship Between Sensory Abnormailities and Repetitive Behaviors In Children with Autism

Background: Restricted, repetitive, and stereotypical behaviors are one of the main core features of autism spectrum disorders (ASD) and are required for the diagnosis of autistic and Asperger’s disorders. Sensory abnormalities are frequently reported in ASD but are not a required criteria for the diagnosis of ASD using DSM-IV. Previous studies have reported a relationship between sensory abnormalities and repetitive behaviors in children with autism, but these studies had limited sample sizes and did not examine the associations with the different repetitive behavior symptoms domains.

Objectives: The purpose of the current study was to further investigate the relationship between specific sensory abnormalities and repetitive behaviors in children with ASD. Additionally, correlations between specific patterns of sensory responses (e.g., hypersensitivity, hypo-underreactive, sensory seeking, and sensory avoiding) and the different domains of repetitive behaviors in children with ASD were examined.

Methods: This investigation included 119 children with ASD. Diagnosis was based on the Autism Diagnostic Instrument-Revised, the Autism Diagnostic Observation Schedule, and expert clinical opinion.  Primary measures included the Sensory Profile Questionnaire (SPQ) and the Repetitive Behavior Scale-Revised (RBS-R). Correlation analyses were conducted to assess the association between repetitive behaviors as measured by the RBS-R and the different factors of the SPQ. Additionally, relationships between RBS-R and its subscales with specific sensory constructs, as measured by factors from the SPQ that are associated with hypersensitivity, hyposensitvity, sensory seeking, and sensory avoiding, were also assessed.

Results: Several associations between sensory deficits and repetitive behaviors were observed. Relationships between total score of the RBS-R and several sensory factors were found including sensory seeking (P< 0.0001), emotional/reactive (p<0.0001) and oral sensitivity (p<0.0001). Correlations between total RBS-R scores and all sensory constructs were found including hypo-underreactive  (p= 0.001) and hypersensitivity (p < 0.0001). Interestingly, associations were observed between all sensory constructs and RBS-R subscales with the strongest being between hypo-underreactive and the sameness behavior scale (p<0.0001) and between hypersensitive and ritualistic behavior subscale (p<0.0001).

Conclusions: Preliminary findings from this investigation suggest the existence of a strong relationship between different types of sensory abnormalities and a variety of repetitive behaviors in children with autism. However, these associations do not shed light on the possible existence of a causal relationship between these two clinical domains. Future cross-sectional and longitudinal investigations should attempt to test these associations by examining the effect of age and cognitive functioning on their development of sensory deficits and repetitive behaviors.