title: Dynamic accommodative response to different visual stimuli (2D vs 3D) while watching television and while playing Nintendo 3DS console.
abstract: OBJECTIVE
  The aim of the present study was to compare the accommodative response to the same visual content presented in two dimensions (2D) and stereoscopically in three dimensions (3D) while participants were either watching a television (TV) or Nintendo 3DS console.
  
  
  METHODS
  Twenty-two university students, with a mean age of 20.3 ± 2.0 years (mean ± S.D.), were recruited to participate in the TV experiment and fifteen, with a mean age of 20.1 ± 1.5 years took part in the Nintendo 3DS console study. The accommodative response was measured using a Grand Seiko WAM 5500 autorefractor. In the TV experiment, three conditions were used initially: the film was viewed in 2D mode (TV2D without glasses), the same sequence was watched in 2D whilst shutter-glasses were worn (TV2D with glasses) and the sequence was viewed in 3D mode (TV3D). Measurements were taken for 5 min in each condition, and these sections were sub-divided into ten 30-s segments to examine changes within the film. In addition, the accommodative response to three points of different disparity of one 3D frame was assessed for 30 s. In the Nintendo experiment, two conditions were employed - 2D viewing and stereoscopic 3D viewing.
  
  
  RESULTS
  In the TV experiment no statistically significant differences were found between the accommodative response with TV2D without glasses (-0.38 ± 0.32D, mean ± S.D.) and TV3D (-0.37 ± 0.34D). Also, no differences were found between the various segments of the film, or between the accommodative response to different points of one frame (p > 0.05). A significant difference (p = 0.015) was found, however, between the TV2D with (-0.32 ± 0.32D) and without glasses (-0.38 ± 0.32D). In the Nintendo experiment the accommodative responses obtained in modes 2D (-2.57 ± 0.30D) and 3D (-2.49 ± 0.28D) were significantly different (paired t-test p = 0.03).
  
  
  CONCLUSIONS
  The need to use shutter-glasses may affect the accommodative response during the viewing of displays, and the accommodative response when playing Nintendo 3DS in 3D mode is lower than when it is viewed in 2D.
authors.affiliation: Clinical and Experimental Optometry Research Laboratory, Centre of Physics (Optometry), School of Sciences, University of Minho, Braga, Portugal. moasilvia@gmail.com
authors.forename: Sílvia
authors.initials: S
authors.lastname: Oliveira
authors.forename: Jorge
authors.initials: J
authors.lastname: Jorge
authors.forename: José M
authors.initials: JM
authors.lastname: González-Méijome
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D003867:Depth Perception / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000379:methods; D013690:Television; D018910:Video Games; D015357:Vision Disparity; D055815:Young Adult