Functional Neuroimaging of Sensory Over-Responsivity in Youth With Autism Spectrum Disorders

In addition to the core social and communication symptoms, individuals with autism spectrum disorders (ASD) have high rates of sensory over-responsivity (SOR). Despite the fact that over half of children and adolescents with ASD have SOR, very little is known about the neurobiological bases of this condition. SOR often co-occurs with anxiety disorders, which suggests a possible common biological basis for both SOR and anxiety in a subgroup of youth with ASD. The following studies used functional magnetic resonance imaging (fMRI) to examine brain response to mildly aversive sensory stimulation in youth with and without ASD, with a focus on brain areas responsible for primary processing of sensory information as well as those linked to anxiety and emotion regulation. Results suggest that youth with ASD and SOR have deficits in both primary sensory processing as well as in regulating emotional response to sensory information. These deficits are associated with reduced amygdala-prefrontal functional connectivity during exposure to sensory stimuli as well as reduced habituation to the stimuli. Findings can inform intervention, including better classification and targeted treatment for subgroups of youth with ASD, and treatment focused on building coping skills for sensory stimulating environments.