Objectives: This study investigates sensory processing profiles in toddlers with and without risk for ASD using the Infant/Toddler Sensory Profile (Dunn & Daniels, 2002). Given the forthcoming criteria in the DSM-V for ASD that includes symptomatology of atypical sensory reactivity, profiles are also examined in comparison to autism symptomatology, developmental and adaptive behavior, and age.
Methods: The Infant/Toddler Sensory Profile (ITSP) was administered to 82 children at three different developmental points during a longitudinal study on infants at risk for ASD. Mean age at the first visit was 12.02 months (SD=0.62), at the second visit was 18.15 months (SD=0.71), and at the third visit was 21.46 months (SD=0.66). Fifty of these children (72.7% male) were at high-risk for developing ASD (i.e., Siblings) and 32 (41.7% male) were low-risk (i.e., non-Siblings). At 24-months, 8 children received confirmatory diagnoses of ASD. Developmental, adaptive, and diagnostic measures included the Mullen Scales of Early Learning, the Vineland Adaptive Behavior Scales, and the ADOS, Toddler Module, respectively.
Results: At 24 months, Siblings showed a significant difference in the ITSP domain of Sensation Avoiding [F(1,80) = 6.01; p<.05] as compared to non-Siblings. For these high risk children, positive correlations were observed between Vineland Socialization scores at 24 months and Sensation Avoiding behaviors at 12 months (r = .48, p<.01), 18-months (r = .35, p<.05), and 24-months (r = .42, p<.01) respectively, indicating that these symptoms were significantly impacting adaptive social functioning by age 2. These associations were not observed in low-risk children. When children were grouped according to diagnostic outcomes at 24-months, significant Sensation Seeking symptoms were evidenced in ASD at 24 months [F(1,77)=4.93; p<.05], whereas Sensation Avoiding [F(1,77)=13.18; p<.01] and Low Registration [F(1,77)=4.03; p<.05] behaviors were more prominent in ASD at 18 months.
Conclusions: This study confirms that toddlers with ASD exhibit atypical sensory-avoidant and low registration symptoms, but only at 18 months, whereas sensory-seeking behaviors appear more prominent at 24-months of age. Of importance, significant findings were observed just based on risk-status alone, with siblings of children with ASD experiencing sensory-avoidant behaviors, as well, particularly at 24 months of age. High-risk siblings also display greater social impairments at 24 months, as compared to children at low risk for ASD. These results suggest that the sensory profile may be important in assisting with the early detection of risk factors for ASD, especially in younger siblings who are at much greater risk than the general population.