Unusual Sensory Behaviors in Infants at Risk for Autism

Background:  

Autism Spectrum Disorder (ASD) is characterized by the presence of social communication deficits as well as restricted and repetitive behaviors (American Psychiatric Association, 2013). Comorbidities in ASD include unusual sensory behaviors (USBs) and this feature has now been incorporated into the DSM 5. To date, little is known about whether USBs can be observed early on in ASD. 

Objectives:  

In the current study, we employed the Infant/Toddler Sensory Profile (ITSP) parent questionnaire (Dunn, 2002) to track USBs in infants at a High-Risk for developing ASD because they have an older sibling with ASD. Although one previous study has used the ITSP in 12-month-olds (Mulligan & White, 2012), the current study is the first to look at multiple time points in order to gain a more comprehensive view.

Methods:  

At two testing sites (University of Connecticut-Storrs and the University of California, San Diego), parents were asked to fill out the ITSP at several time points from 3 to 36 months.  The final data sample included 32 High-Risk infants, and for comparison, 39 Low-Risk infants (i.e., infants from families with no history of ASD). The ITSP was used to determine USBs (i.e., outside the “typical” range) within each of the five sensory processing domains (low registration, sensation seeking, sensory sensitivity, sensation avoidance, and low threshold) and five sensation types (auditory, visual, vestibular, tactile, and oral). In our sample, for each domain, we asked whether – at any time point – a child’s ITSP score was indicative of USBs, in which case, they were given a score of “1”, or else, the child received a score of “0”.

Results:  

In terms of sensory processing domains, greater proportion of USBs were observed in High-Risk than Low-Risk infants, specifically in the domains of low registration (High-Risk=78.1%, Low-Risk=46.2%, x² = 41.2, p <.001), sensation avoidance (High-Risk=62.5%, Low-Risk=41%, x² = 20, p <.001), and low threshold (High-Risk= 62.5%, Low-Risk= 41%, x² = 20, p <.001).  In contrast, sensation seeking and sensory sensitivity domains showed no group differences. In terms of the various sensation types, greater proportion of USBs were observed in the auditory (High-Risk= 68.8%, Low-Risk= 53.8%, x² = 9.1, p<.01), visual (High-Risk= 71.9%, Low-Risk= 51.3%, x² = 17.6, p <.001), tactile (High-Risk= 90.6%, Low-Risk= 64.1%, x² = 31.6, p<.001), and vestibular (High-Risk= 93.8%, Low-Risk= 43.6%, x²= 101.5, p<.001) sensations. There were no significant differences in oral processing.

Conclusions:  

Infants at a High-Risk for ASD showed elevated unusual sensory behaviors compared to Low-Risk infants within multiple sensory processing domains and sensation types. These results have implications for early interventions that target sensory processing abilities in ASD. To be clear, clinicians must screen for USBs in High-Risk infants and address them through appropriate sensori-motor and behavioral interventions.