title: The effect of occlusive patching on visually-directed tasks.
abstract: OBJECTIVE
  Occlusive patching is used to treat a variety of ocular conditions. A paucity of literature exists regarding the effects of occlusion on functional tasks and driving performance. We investigated the immediate effects of occlusive patching on a variety of visually dependent tasks as well as driving performance on a simulator.
  
  
  METHODS
  Thirty normally sighted subjects were examined in a prospective randomized manner. All subjects underwent a complete medical history and eye examination. All subjects performed a variety of near tasks and drove a driving simulator with and without patching. The tasks included traditional clinical depth tests, tests of visual memory, scanning, and tracking, and gross and fine-motor abilities. All subjects filled out a questionnaire relating to their perception of the effects of patching on functional tasks and driving ability.
  
  
  RESULTS
  Visual memory, scanning, tracking, and perceptual constancy were unaffected by patching. However, there were significant differences between the patched and unpatched conditions for four of five of the three-dimensional visual coordination tasks. Eight of 19 (42%) of the fine-motor tasks and 4 of 9 gross-motor tasks (44%) showed significant differences between the patched and unpatched conditions. A greater frequency of out of lane events and more abrupt braking profiles were seen when subjects drove monocularly rather than binocularly.
  
  
  CONCLUSIONS
  Sudden occlusion immediately changes perceptual ability by decreasing visual field and eliminating stereoacuity. This has important implications for the performance of everyday tasks.
authors.affiliation: Department of Ophthalmology and Visual Sciences, The University of Chicago, 1855 West Taylor Street, Chicago, IL 60612, USA.
authors.forename: Balaji
authors.initials: B
authors.lastname: Gupta
authors.forename: Jennifer
authors.initials: J
authors.lastname: Paliga
authors.forename: Denice J
authors.initials: DJ
authors.lastname: Laderman
authors.forename: Janet P
authors.initials: JP
authors.lastname: Szlyk
mesh_terms: D000293:Adolescent; D000328:Adult; D003867:Depth Perception / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011597:Psychomotor Performance / Q000502:physiology; D012016:Reference Values; D012683:Sensory Deprivation / Q000502:physiology*; D013647:Task Performance and Analysis; D015349:Vision, Monocular / Q000502:physiology*