Neurobiology of Sensory Overresponsivity in Youth With Autism Spectrum Disorders.

ABSTRACT: IMPORTANCE:More than half of youth with autism spectrum disorders (ASDs) have sensory overresponsivity (SOR), an extreme negative reaction to sensory stimuli. However, little is known about the neurobiological basis of SOR, and there are few effective treatments. Understanding whether SOR is due to an initial heightened sensory response or to deficits in regulating emotional reactions to stimuli has important implications for intervention. OBJECTIVE:To determine differences in brain responses, habituation, and connectivity during exposure to mildly aversive sensory stimuli in youth with ASDs and SOR compared with youth with ASDs without SOR and compared with typically developing control subjects. DESIGN, SETTING, AND PARTICIPANTS:Functional magnetic resonance imaging was used to examine brain responses and habituation to mildly aversive auditory and tactile stimuli in 19 high-functioning youths with ASDs and 19 age- and IQ-matched, typically developing youths (age range, 9-17 years). Brain activity was related to parents' ratings of children's SOR symptoms. Functional connectivity between the amygdala and orbitofrontal cortex was compared between ASDs subgroups with and without SOR and typically developing controls without SOR. The study dates were March 2012 through February 2014. MAIN OUTCOMES AND MEASURES:Relative increases in blood oxygen level-dependent signal response across the whole brain and within the amygdala during exposure to sensory stimuli compared with fixation, as well as correlation between blood oxygen level-dependent signal change in the amygdala and orbitofrontal cortex. RESULTS:The mean age in both groups was 14 years and the majority in both groups (16 of 19 each) were male. Compared with neurotypical control participants, participants with ASDs displayed stronger activation in primary sensory cortices and the amygdala (P??1.70, P?

SUBMITTER: Green SA 

PROVIDER: S-EPMC4861140 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature