title: The influence of a central stimulus on visual field measurements in children from 3.5 to 30 months of age.
abstract: OBJECTIVE
  To provide normative data on the effect of a central competing stimulus on monocular visual field extent in 3.5- to 9-month-olds and adults, and binocular visual field extent in 11- to 30-month-olds.
  
  
  METHODS
  Visual field extent along diagonal meridia was measured in 180 infants and children (N = 30 at 3.5, 7, 9, 11, 17, and 30 months) and 20 adults, using static perimetry. Stimuli were 3-deg, 10-Hz flickering, yellow light-emitting diodes (LEDs). Each subject was tested with 12 trials in which the central stimulus remained on and 12 trials in which the central stimulus was turned off during presentation of the peripheral stimulus.
  
  
  RESULTS
  A competing stimulus produced a decreased frequency of eye movements at 17 months and evidence suggestive of decreased measured field extent at 17 and 30 months.
  
  
  CONCLUSIONS
  A continuously present central stimulus does not produce underestimation of visual field extent in 3.5- to 9-month-old infants with normal vision and adults tested monocularly and 11-month-old infants tested binocularly. However, visual field extent may be underestimated in 1- and 2-year-olds if a competing central stimulus is used.
authors.affiliation: Department of Ophthalmology, University of Arizona, Tucson, USA. emh@ccit.arizona.edu
authors.forename: E M
authors.initials: EM
authors.lastname: Harvey
authors.forename: V
authors.initials: V
authors.lastname: Dobson
authors.forename: D B
authors.initials: DB
authors.lastname: Narter
mesh_terms: D000328:Adult; D000375:Aging / Q000502:physiology*; D001288:Attention / Q000502:physiology; D002675:Child, Preschool; D005133:Eye Movements / Q000502:physiology; D006801:Humans; D007223:Infant; D010775:Photic Stimulation; D015348:Vision, Binocular / Q000502:physiology; D015349:Vision, Monocular / Q000502:physiology; D058609:Visual Field Tests / Q000379:methods*; D014794:Visual Fields / Q000502:physiology*