title: Altered activity of the primary visual area during gaze processing in individuals with high-functioning autistic spectrum disorder: a magnetoencephalography study.
abstract: BACKGROUND
  Individuals with autistic spectrum disorder (ASD) demonstrate an impaired ability to infer the mental states of others from their gaze. Thus, investigating the relationship between ASD and eye gaze processing is crucial for understanding the neural basis of social impairments seen in individuals with ASD. In addition, characteristics of ASD are observed in more comprehensive visual perception tasks. These visual characteristics of ASD have been well-explained in terms of the atypical relationship between high- and low-level gaze processing in ASD.
  
  
  METHODS
  We studied neural activity during gaze processing in individuals with ASD using magnetoencephalography, with a focus on the relationship between high- and low-level gaze processing both temporally and spatially. Minimum Current Estimate analysis was applied to perform source analysis of magnetic responses to gaze stimuli.
  
  
  RESULTS
  The source analysis showed that later activity in the primary visual area (V1) was affected by gaze direction only in the ASD group. Conversely, the right posterior superior temporal sulcus, which is a brain region that processes gaze as a social signal, in the typically developed group showed a tendency toward greater activation during direct compared with averted gaze processing.
  
  
  CONCLUSIONS
  These results suggest that later activity in V1 relating to gaze processing is altered or possibly enhanced in high-functioning individuals with ASD, which may underpin the social cognitive impairments in these individuals.
authors.affiliation: Department of Psychiatry, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Hasegawa
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kitamura
authors.forename: Hiroatsu
authors.initials: H
authors.lastname: Murakami
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kameyama
authors.forename: Mutsuo
authors.initials: M
authors.lastname: Sasagawa
authors.forename: Jun
authors.initials: J
authors.lastname: Egawa
authors.forename: Ryu
authors.initials: R
authors.lastname: Tamura
authors.forename: Taro
authors.initials: T
authors.lastname: Endo
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Someya
mesh_terms: D000328:Adult; D001321:Autistic Disorder / Q000503:physiopathology*; D001931:Brain Mapping; D005149:Facial Expression; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D012938:Social Perception; D014793:Visual Cortex / Q000503:physiopathology*; D055815:Young Adult