title: Modulation of mu attenuation to social stimuli in children and adults with 16p11.2 deletions and duplications.
abstract: BACKGROUND
  Copy number variations (CNV) within the recurrent ~600 kb chromosomal locus of 16p11.2 are associated with a wide range of neurodevelopmental disorders, including autism spectrum disorder (ASD). However, little is known about the social brain phenotype of 16p11.2 CNV and how this phenotype is related to the social impairments associated with CNVs at this locus. The aim of this preliminary study was to use molecular subtyping to establish the social brain phenotype of individuals with 16p11.2 CNV and how these patterns relate to typical development and ASD.
  
  
  METHODS
  We evaluated the social brain phenotype as expressed by mu attenuation in 48 children and adults characterized as duplication carriers (n = 12), deletion carriers (n = 12), individuals with idiopathic ASD (n = 8), and neurotypical controls (n = 16). Participants watched videos containing social and nonsocial motion during electroencephalogram (EEG) acquisition.
  
  
  RESULTS
  Overall, only the typical group exhibited predicted patterns of mu modulation to social information (e.g., greater mu attenuation for social than nonsocial motion). Both 16p11.2 CNV groups exhibited more mu attenuation for nonsocial than social motion. The ASD group did not discriminate between conditions and demonstrated less mu attenuation compared to the typical and duplication carriers. Single-trial analysis indicated that mu attenuation decreased over time more rapidly for 16p11.2 CNV groups than the typical group. The duplication group did not diverge from typical patterns of mu attenuation until after initial exposure.
  
  
  CONCLUSIONS
  These results indicate atypical but unique patterns of mu attenuation for deletion and duplication carriers, highlighting the need to continue characterizing the social brain phenotype associated with 16p11.2 CNVs.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, 1959 Northeast Pacific Street #115, Seattle, WA 98195 USA.
authors.forename: Caitlin M
authors.initials: CM
authors.lastname: Hudac
authors.affiliation: Seattle Children's Research Institute, 2001 8th Avenue #400, Seattle, WA 98121 USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Kresse
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, 1959 Northeast Pacific Street #115, Seattle, WA 98195 USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Aaronson
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, 1959 Northeast Pacific Street #115, Seattle, WA 98195 USA.
authors.forename: Trent D
authors.initials: TD
authors.lastname: DesChamps
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, 1959 Northeast Pacific Street #115, Seattle, WA 98195 USA.|Seattle Children's Research Institute, 2001 8th Avenue #400, Seattle, WA 98121 USA.
authors.forename: Sara Jane
authors.initials: SJ
authors.lastname: Webb
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, 1959 Northeast Pacific Street #115, Seattle, WA 98195 USA.
authors.forename: Raphael A
authors.initials: RA
authors.lastname: Bernier
keywords: 16p11.2; Autism spectrum disorder (ASD); Copy number variation (CNV); Electroencephalogram (EEG); Molecular subtyping; Mu attenuation; Social perception