Sensory Processing Profile and Autistic Symptoms As Predictive Factors in Neurodevelopmental Disorder Diagnosis

Background: Unusual sensory responses have been consistently reported as common in autism spectrum disorder (ASD) and were recently included in the diagnostic criteria. Sensory difficulties are also common among individuals with other neurodevelopmental disorders, including Williams syndrome (WS, a genetic condition characterized by developmental delays, learning disabilities and cardiovascular problems). Cross-syndrome comparisons of sensory atypicalities and the evaluation of their syndrome-specificity, however, have rarely been undertaken. This analysis would enable us to determine whether there are unique syndrome-specific sensory signatures, which in turn may assist with differential diagnosis and tailored interventions. 

Objectives: The aims of this study were: (a) to examine and compare the sensory profiles in three groups of children and adolescents; those with a diagnosis of ASD without learning disabilities (LD), ASD with learning disabilities and those with WS; (b) to investigate whether autistic symptoms, including sensory processing scores can predict a group membership.   

Methods: Parents of 21 children with ASD and LD, 22 parents of children with ASD (no LD) and 18 with WS, aged between 4 and 16 years were recruited. Parents completed the Sensory Profile (SP; Dunn, 1999) to provide information about their child’s sensory experiences and the Social Responsiveness Scale – second edition (SRS-2; Constantino & Gruber, 2012) to assess the degree of social impairment in their child.   

Results: No significant differences were found in sensory processing scores between the three groups.  Regression analyses were undertaken with sensory quadrants (Low Registration, Sensory Sensitivity, Sensation Seeking, and Sensory Avoiding) and SRS-2 total score as factors. Multinomial logistic regression was not possible due to similarities between the ASD groups. Binary logistic regression models were run for WS and ASD without LD; and WS and ASD with LD individually. Models significantly predicted group membership.  In the WS and ASD no LD model Low Registration (β=.345, S.E.=.158, p=.029), Sensory Sensitivity (β=.383, S.E.=.193, p=.048) and SRS-2 total score (β=.178, S.E.=.078, p=.022) were significant predictors in the model, while in the WS and ASD with LD model there were only two significant predictors: Low Registration (β=.201, S.E.=.092, p=.028) and SRS-2 total score (β=.154, S.E.=.057, p=.007).

Conclusions: The findings suggest that sensory profiles of children and adolescents with WS and ASD are very similar. High rates of general sensory atypicality generally, therefore, are not autism-specific, but are a common neurodevelopmental characteristic that do not reliably distinguishing between WS and ASD groups. Low Registration and Sensory Sensitivity related behaviours might, however, be more specific to ASD. Further work is needed to explore behaviours within the sensory profiles that can discriminate between neurodevelopmental disorders and which therefore should be included in diagnostic classifications.