This study aims to examine the specific effect that 3D game play has on the control of the eyes horizontal movements. It will examine the youngest group of consumers this technology is marketed to, 7 to 11-year-olds and no children under 7 years of age will be recruited to this study as per Nintendo's hardware guidelines, which recommends that children under 7 years of age not play in 3D mode. It will examine the effect of playing in 3D for 30 minutes on horizontal fusional amplitudes compared with a control group playing in 2D for 30 minutes.

This study will be a prospective blind randomised control trial. The participants will be randomised into one study group, with participants playing a game in 3D; and a control group, with participants playing the same game in 2D. The study is blind due to the use of an independent assessor, reducing testing bias by ensuring that the tester does not know the randomisation results. The known dependant variables are the total horizontal fusional amplitudes at 1/3m and 6m and the independent variable is the use of 2D or 3D game play.

Inclusion Criteria:

• Male and female 7 to 11-year-olds with no prior history of binocular vision / ocular motility dysfunction.

Exclusion Criteria:

• Corrected visual acuity of less than 0.000 tested with SLT at 3m.

  • Interocular visual acuity difference of 0.100 (tested with SLT) or greater, which could indicate the presence of Amblyopia.
  • The presence of any manifest deviation (Tropia).
  • Presence of any ocular motility dysfunction, which affects primary position.
  • Reduced binocular convergence of 10 centimetres or less.
  • Stereoacuity of less than 170" (this may indicate the presence of a microtropia or other undiagnosed pathology).
  • Any prior or existing medical history of epilepsy or seizures.
  • Any prior or existing medical history of repetitive strain injury.