title: Altered tactile processing in children with autism spectrum disorder.
abstract: Although tactile reactivity issues are commonly reported in children with autism spectrum disorder (ASD), the underlying mechanisms are poorly understood. Less feed-forward inhibition has been proposed as a potential mechanism for some symptoms of ASD. We tested static and dynamic tactile thresholds as a behavioral proxy of feed-forward inhibition in 42 children (21 children with ASD and 21 typically developing [TD] children). Subthreshold conditioning typically raises the dynamic detection threshold, thus comparison of the dynamic to the static threshold generates a metric that predicts gamma-aminobutyric acid (GABA) mediated feed-forward inhibition. Children with ASD had marginally higher static thresholds and a significantly lower ratio between thresholds as compared with TD children. The lower ratio, only seen in children with ASD, might be indicative of less inhibition. Static thresholds were correlated with autism spectrum quotient scores, indicating the higher the tactile threshold, the more ASD traits. The amount of feed-forward inhibition (ratio between dynamic/static) was negatively correlated with autism diagnostic observation schedule repetitive behavior scores, meaning the less inhibition the more ASD symptoms. In summary, children with ASD showed altered tactile processing compared with TD children; thus measuring static and dynamic thresholds could be a potential biomarker for ASD and might be useful for prediction of treatment response with therapeutics, including those that target the GABAergic system. Autism Res 2016, 9: 616-620. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.
authors.affiliation: Department of Psychiatry, Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.
authors.forename: Teresa
authors.initials: T
authors.lastname: Tavassoli
authors.affiliation: University of Missouri.
authors.forename: Katherine
authors.initials: K
authors.lastname: Bellesheim
authors.affiliation: Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, 27599.
authors.forename: Mark
authors.initials: M
authors.lastname: Tommerdahl
authors.affiliation: Department of Biomedical Engineering, University of North Carolina, Chapel Hill, NC, 27599.
authors.forename: Jameson M
authors.initials: JM
authors.lastname: Holden
authors.affiliation: Department of Psychiatry, Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|Department of Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kolevzon
authors.affiliation: Department of Psychiatry, Seaver Autism Center for Research and Treatment, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|The Mindich Child Health and Development Institute, Icahn School of Medicine at Mount Sinai, New York, NY, 10029.|The Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, New York, NY.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Buxbaum
mesh_terms: D000067877:Autism Spectrum Disorder / Q000150:complications* / Q000503:physiopathology*; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D010468:Perceptual Disorders / Q000150:complications* / Q000503:physiopathology*; D055698:Touch Perception / Q000502:physiology*
keywords: GABA; autism spectrum disorder; inhibition; tactile processing