Sensory Processing Relationships to Autism Spectrum Disorder Risk in Toddlers Diagnosed with ASD

Background:  Early identification of ASD in young children creates opportunity for early intervention to improve outcomes.  Sensory processing differences are common in toddlers with an ASD (Ben-Sasson et al., 2007) and been reported to predate diagnosis (Adrien et al., 1993; Baranek, 1999; Dahlgren & Gillberg, 1989; Lord, 1995). This, coupled with the addition of the new DSM-5 item related to hyper- or hypo-reactivity to sensory input or unusual interests in sensory aspects of the environment (APA, 2014) heightens the need to better understand sensory processing in toddlers with ASD and the relationship to early screening measures. Therefore, the purpose of this study was to examine the extent to which sensory processing patterns are related to autism spectrum disorder (ASD) risk status as measured by the MCHAT and STAT in very young children with a diagnosis.

Objectives:  Understand the relationships between sensory processing patterns in toddlers and ASD risk as measured by ASD screenings

Methods:  We analyzed developmental and sensory processing variables from the diagnostic evaluation process.  Participants included children with a diagnosis of ASD (n=60), mean age 27.82 months (SD=4.98; range=17-35 mos). The sample currently includes 43 boys and 17 girls; sample size will increase to n=75 by time of presentation. Sensory pattern variables were compared to ASD screenings.  We used the Toddler Sensory Profile-2 (Dunn, 2014), the Modified Checklist for Autism in Toddlers series (M-CHAT) (Robins et al., 2001; 2013), and the Screening Tool for Autism in Toddlers & Young Children (STAT) (Stone et al., 2000).

Results:  Preliminary results suggest that sensitivity and registration scores were positively associated with MCHAT total risk score (p<.01 and p<.05, respectively).  Although sensory processing scores were not significantly associated with STAT total risk score, analysis of STAT subscale risk scores showed that sensitivity and registration neared significance with directing attention (p=.077 and p=.081, respectively). 

Conclusions:  Research suggests that the ways in which toddlers process sensory information contributes to participation in daily routines and to their overall development. Caregivers of children with ASD notice sensory processing differences early in development, particularly when children show aversion to sensory experiences (i.e., sensitivity) or seem to be unaware of sensory stimuli (i.e., registration).   In this very young sample of children with ASD, sensitivity and registration were associated with early risk scores on ASD screening measures. It may be that particular behaviors associated with these patterns illuminate aspects of early development in ASD, providing potential avenues for both early identification and intervention approaches in this population.