title: Delayed visual orienting responses in children with developmental and/or intellectual disabilities.
abstract: BACKGROUND
  Assessment of higher visual processing functions mostly requires active cooperation of participants, which is problematic in children with intellectual disabilities (ID). To circumvent this, we applied remote eye tracking to quantify (ab)normal visual orienting responses in children with ID in terms of reaction times to visual stimuli.
  
  
  METHODS
  We presented visual stimuli (cartoon, coherent form, and coherent motion) to 127 children (2-14 years) with developmental and/or ID (risk group) and simultaneously measured their orienting ocular motor responses. Reaction times to fixation (RTF) in the risk group were compared with RTF values of an age-matched control group.
  
  
  RESULTS
  Overall, in 72% of the children in the risk group, RTF values to cartoon were delayed, in 47% to form, and in 38% to motion. The presence of delayed reaction times was highest in the group of children >4 years with ID.
  
  
  CONCLUSIONS
  Our data show that a majority of children with developmental and/or ID have delayed visual orienting responses. This suggests that this group has increased risk for higher visual processing dysfunctions. Future studies are planned to correlate abnormal orienting responses to type of brain damage and to dissociate the responses from ocular motor disorders.
authors.affiliation: Vestibular and Ocular Motor Research Group, Department of Neuroscience, Erasmus MC, Rotterdam, The Netherlands Intellectual Disability Medicine, Department of General Practice, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: F H
authors.initials: FH
authors.lastname: Boot
authors.forename: J J M
authors.initials: JJ
authors.lastname: Pel
authors.forename: M P
authors.initials: MP
authors.lastname: Vermaak
authors.forename: J
authors.initials: J
authors.lastname: van der Steen
authors.forename: H M
authors.initials: HM
authors.lastname: Evenhuis
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000453:epidemiology / Q000503:physiopathology*; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology; D005556:Form Perception / Q000502:physiology*; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology / Q000503:physiopathology*; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009949:Orientation / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D015995:Prevalence; D011930:Reaction Time / Q000502:physiology; D012307:Risk Factors