Abnormal Parent-Reported Sensory Behaviors in ASD and ADHD

Background: Abnormal sensory behaviors are among the most common behavioral concerns of parents of children with autism spectrum disorders (ASD), often causing significant family stress.  Recent reports have suggested that abnormal sensory behaviors are also present in other developmental disabilities (e.g., Attention Deficit/Hyperactivity Disorder: ADHD, Tourette Syndrome).  It is, however, unclear whether the nature or severity of these behaviors differs among disorders or is more specific to ASD.

Objectives:  To examine differences between parent-reported sensory behavior in children with ASD, ADHD, and typically developing (TD) children using the Sensory Processing Measure (SPM). 

Methods:  Data came from ongoing studies examining motor skill development and learning in children with ASD and ADHD.  Diagnosis of autism was made using the Autism Diagnostic Interview-Revised (ADI-R), and the Autism Diagnostic Observation Schedule (ADOS-G). Diagnosis of ADHD was made using structured parent interview, (Diagnostic Interview for Children and Adolescents, Fourth Edition: DICA-IV) and ADHD-specific and broad behavior rating scale (Conners’ Parent Rating Scale-Revised, Long Form, CPRS-R).  To measure sensory behavior, the SPM was administered.  The SPM is a parent-report of sensory behavior assessing sensory processing, praxis, and social participation; individual subscale and total sensory systems were examined by group. Groups included ASD (n=34), ADHD (n=25) and TD (n=53).  The age of the sample ranged from 8-12 years (M=10.4, SD=1.3), and participants were included with at least average intelligence (Wechsler Intelligence Scale for Children-Fourth Edition: WISC-IV Perceptual Reasoning Index: PRI): ASD (M=105.6, SD=14.1), ADHD (M=101.2, SD=10.8), and TD (M=109.4, SD=1.7).  Results of an ANOVA revealed a main effect for PRI (F_(2,109) = 3.6, p=.03), with bivariate analyses revealing a significant difference only a  between ADHD and TD (t(2,56)=-1.3, p=.006).

Results:  ANOVA revealed highly significant differences (p <.001) between groups across all subscales of the SPM (e.g., SPM Total Sensory Systems: F_(2,111) = 81.1, p<001).   Bivariate analyses revealed for every subscale (i.e., Social Participation, Vision, Hearing, Touch, Body Awareness, Body Motion, Planning, and Total Sensory Systems), ASD were rated by parents as having significantly worse sensory behavior than ADHD, who were rated as having significantly worse sensory behavior than TD children.  Of note, although ADHD were rated as having statistically more sensory behavior difficulties than TD children, both ADHD and TD children were reported to fall within 1 SD of the mean across subscales (e.g., SPM Total Sensory Systems M_ADHD=53.6, SD=8.6, M_TD=44.3, SD=4.8); only children with ASD were rated as 1 SD above the mean across subscales (e.g., SPM Total Sensory Systems M_ASD=62.8, SD=7.6), suggesting some clinical impairment. 

Conclusions:   Though parents of children with both ASD and ADHD report greater concern than TD children with regard to abnormal sensory behaviors, the level of concern is statically and clinically greatest for children with ASD across multiple aspects of sensory functioning (e.g., hearing, vision, touch).  As such, as described in the literature, abnormal sensory behaviors may not be specific to ASD, but may be more substantial in this disorder.