The Relationship between Sensory over-Responsivity, Emotion Dysregulation Symptoms, and Psychophysiological Arousal to Sensory Stimuli in Youth with ASD

Background: Sensory over-responsivity (SOR) in youth with Autism Spectrum Disorder (ASD) is related to significant impairment in functioning, including greater emotional and behavioral symptoms (Ben-Sasson et al., 2009). Emotion dysregulation, the inability to effectively modulate emotions in response to an emotional experience, is a common area of difficulty found in ASD (Samson et al. 2014), but is rarely examined directly in relation to SOR. Emotion dysregulation also co-occurs with other negative outcomes including increased anxiety, depression, and poorer social functioning (Mazefsky et al., 2015) as well as observable maladaptive behaviors such as deliberate self-harm, tantrums, physical altercations with others, and general increases in irritability, nervousness, and worry (Quek et al., 2012; Lerner et al., 2012). It is possible that when individuals with ASD are exposed to aversive environmental stimuli, the need to modulate incoming sensory information disrupts adaptive emotional processing resulting in increased emotion dyrsregulation (Mazefsky et al., 2015). There is evidence that children with ASD show one of two patterns of psychophysiological arousal in response to sensory stimuli: either high arousal and slow habituation or low arousal and high habituation (Schoen et al., 2008). However, it is unclear whether and how these patterns may relate to SOR and/or to emotional arousal more generally. Thus, we sought to examine the relative contributions of SOR and emotion dysregulation to physiological responses to sensory stimuli.

Objectives: To examine the relationship between emotion dysregulation, sensory over-responsivity, and physiological arousal in youth with ASD.

Methods: Participants were 37 children and adolescents with ASD, aged 8-17 years. Participants completed a psychophysiological assessment measuring skin conductance response (SCR) across 6 15-sec blocks of mildly aversive, simultaneous auditory and tactile stimuli (white noise and a scratchy sponge). Sensory over-responsivity (SOR) was measured using a composite score from parent reports on the tactile and auditory sensory sensitivity items of the Short Sensory Profile (Dunn, 1999) and Sensory Over-Responsivity Inventory (Schoen et al., 2008). Emotion dysregulation was measured using parent report on the Emotion Dysregulation Index (EDI; Samson et al., 2014) of the Child Behavior Checklist (CBCL).

Results: A repeated-measures ANOVA with the 6 blocks of SCR response as within-subjects factors and SOR and ED as between-subject factors showed a main effect of SCR decreasing over time (p<.001). There was a significant SCR*SOR interaction (p<.05) such that SCR decreased less over time for youth with high (more severe) SOR. There was also a main effect of ED (p<.05) such that youth with high (more severe) ED had higher SCR arousal across all 6 blocks.

Conclusions: Results demonstrate that both SOR and emotion dysregulation play a role in physiological response to sensory stimuli in youth with ASD. Emotion dysregulation may be more directly related to high overall arousal, whereas SOR may be related to decreased habituation to sensory stimuli (consistent with Green et al., 2015, where the same pattern was observed with amygdala response to sensory stimuli). Results will be discussed in terms of implications for including emotion regulation strategies in intervention for SOR.