An Active Approach to Treat Amblyopia: Perceptual Learning and Video Games

Amblyopia, a developmental abnormality that impairs spatial vision, is a major cause of vision loss, resulting in reduced visual acuity and reduced sensitivity to contrast. This study uses psychophysical measures to study neural plasticity in both adults and children with amblyopia.

Amblyopia, a developmental abnormality that impairs spatial vision, is a major cause of vision loss, resulting in reduced visual acuity and reduced sensitivity to contrast. Our previous findings (see CITATIONS) show that the adult amblyopic brain is still plastic and malleable, suggesting that active approach is potential useful in treating amblyopia. The goal of this project is to assess the limits and mechanisms of neural plasticity in both normal and amblyopic spatial vision. This study uses psychophysical measures to study neural plasticity in both adults and children with amblyopia. Research participants will be asked to practice a visual discrimination task (perceptual learning) or to play video games with the amblyopic eye for a period of time. A range of visual functions will be monitored during the course of treatment.

amblyopia treatment, neural plasticity, perceptual learning, vision therapy, spatial vision, video games, occlusion therapy

Patients will be asked to practice a range of visual discrimination tasks for a period of time (each therapy session:1-2 hrs, 4-5 sessions/wk for ~1-6 months).

The fellow sound will be covered with a standard eye patch for a period of time (1-2 hrs/day, 4-5 days/wk for ~1-3 months). The idea is to push the brain to use the weaker amblyopic eye.

Patients will be asked to play videogames for a period of time (each therapy session:1-2 hrs, 4-5 sessions/wk for ~1-6 months).

Research participants will be asked to practice a visual discrimination task (e.g. position acuity, contrast sensitivity, stereoacuity etc) in our laboratory for a period of time (2 hrs/day, 5 days/week).

Research participants will be asked to play "off-the-shelf" video games in our laboratory for a period of time (2 hrs/day, 5 days/week).

Research participants will be required to cover the good eye during the day in order to push the brain to use the amblyopic eye (2 hrs/day, 5 days/week for 2-4 weeks).

Inclusion Criteria: adults and children (>5 years old) with normal vision or amblyopia amblyopia: interocular VA difference of at least 0.1 logMAR Exclusion Criteria: any ocular pathological conditions, nystagmus

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