title: A functional neuroimaging study of fusiform response to restricted interests in children and adolescents with autism spectrum disorder.
abstract: BACKGROUND
  While autism spectrum disorder (ASD) is characterized by both social communication deficits and restricted and repetitive patterns of behavior and interest, literature examining possible neural bases of the latter class of symptoms is limited. The fusiform face area (FFA) is a region in the ventral temporal cortex that not only shows preferential responsiveness to faces but also responds to non-face objects of visual expertise. Because restricted interests in ASD are accompanied by high levels of visual expertise, the objective of this study was to determine the extent to which this region responds to images related to restricted interests in individuals with ASD, compared to individuals without ASD who have a strong hobby or interest.
  
  
  METHODS
  Children and adolescents with and without ASD with hobbies or interests that consumed a pre-determined minimum amount of time were identified, and the intensity, frequency, and degree of interference of these interests were quantified. Each participant underwent functional magnetic resonance imaging (fMRI) while viewing images related to their personal restricted interests (in the ASD group) or strong interest or hobby (in the comparison group). A generalized linear model was used to compare the intensity and spatial extent of fusiform gyrus response between groups, controlling for the appearance of faces in the stimuli.
  
  
  RESULTS
  Images related to interests and expertise elicited response in FFA in both ASD and typically developing individuals, but this response was more robust in ASD.
  
  
  CONCLUSIONS
  These findings add neurobiological support to behavioral observations that restricted interests are associated with enhanced visual expertise in ASD, above and beyond what would be expected for simply a strong interest. Further, the results suggest that brain regions associated with social functioning may not be inherently less responsive in ASD, but rather may be recruited by different environmental stimuli. This study contributes to our understanding of the neural basis of restricted interests in ASD and may provide clues toward developing novel interventions.
authors.affiliation: Yale University Child Study Center, 230 South Frontage Rd, New Haven, CT USA ; Seaver Autism Center for Research and Treatment, Department of Psychiatry, Icahn School of Medicine at Mount Sinai, One Gustave Levy Place Box 1230, New York, NY USA.
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Foss-Feig
authors.affiliation: Department of Psychology, Vanderbilt University, 2301 Vanderbilt Place, Nashville, TN USA.
authors.forename: Rankin W
authors.initials: RW
authors.lastname: McGugin
authors.affiliation: Department of Psychology, Vanderbilt University, 2301 Vanderbilt Place, Nashville, TN USA.
authors.forename: Isabel
authors.initials: I
authors.lastname: Gauthier
authors.affiliation: Department of Psychiatry, Vanderbilt University, 1601 23rd Ave South, Suite 3057, Nashville, TN 37212 USA.
authors.forename: Lisa E
authors.initials: LE
authors.lastname: Mash
authors.affiliation: Yale University Child Study Center, 230 South Frontage Rd, New Haven, CT USA.
authors.forename: Pamela
authors.initials: P
authors.lastname: Ventola
authors.affiliation: Department of Psychiatry, Vanderbilt University, 1601 23rd Ave South, Suite 3057, Nashville, TN 37212 USA ; Vanderbilt Kennedy Center, Nashville, TN USA.
authors.forename: Carissa J
authors.initials: CJ
authors.lastname: Cascio
keywords: Autism spectrum disorder; Expertise; Fusiform face area; Fusiform gyrus; Restricted interests; fMRI