title: Parsing heterogeneity in autism spectrum disorders: visual scanning of dynamic social scenes in school-aged children.
abstract: OBJECTIVE
  To examine patterns of variability in social visual engagement and their relationship to standardized measures of social disability in a heterogeneous sample of school-aged children with autism spectrum disorders (ASD).
  
  
  METHODS
  Eye-tracking measures of visual fixation during free-viewing of dynamic social scenes were obtained for 109 children with ASD (mean age, 10.2 ± 3.2 years), 37 of whom were matched with 26 typically-developing (TD) children (mean age, 9.5 ± 2.2 years) on gender, age, and IQ. The smaller subset allowed between-group comparisons, whereas the larger group was used for within-group examinations of ASD heterogeneity.
  
  
  RESULTS
  Between-group comparisons revealed significantly attenuated orientation to socially salient aspects of the scenes, with the largest effect size (Cohen's d = 1.5) obtained for reduced fixation on faces. Within-group analyses revealed a robust association between higher fixation on the inanimate environment and greater social disability. However, the associations between fixation on the eyes and mouth and social adaptation varied greatly, even reversing, when comparing different cognitive profile subgroups.
  
  
  CONCLUSIONS
  Although patterns of social visual engagement with naturalistic social stimuli are profoundly altered in children with ASD, the social adaptivity of these behaviors varies for different groups of children. This variation likely represents different patterns of adaptation and maladaptation that should be traced longitudinally to the first years of life, before complex interactions between early predispositions and compensatory learning take place. We propose that variability in these early mechanisms of socialization may serve as proximal behavioral manifestations of genetic vulnerabilities.
authors.affiliation: University of Maryland, MD, USA.
authors.forename: Katherine
authors.initials: K
authors.lastname: Rice
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Moriuchi
authors.forename: Warren
authors.initials: W
authors.lastname: Jones
authors.forename: Ami
authors.initials: A
authors.lastname: Klin
mesh_terms: D000293:Adolescent; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis / Q000523:psychology; D005133:Eye Movements; D005260:Female; D005403:Fixation, Ocular; D006801:Humans; D008297:Male; D009040:Motion Pictures; D009483:Neuropsychological Tests; D010553:Personality Development; D010775:Photic Stimulation / Q000295:instrumentation / Q000379:methods; D011569:Psychiatric Status Rating Scales; D012917:Social Adjustment; D014796:Visual Perception