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

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Improving Spatial and Temporal Vision in Adult and Juvenile Amblyopia

Conditions
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Amblyopia

Intervention / Treatment
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* Behavioral: Perceptual learning
* Behavioral: Video Games
* Behavioral: Occlusion therapy


Participation Criteria
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Eligibility Criteria
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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

Ages Eligible for Study
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Minimum Age: 5 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Perceptual learning<br>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). | Behavioral: Perceptual learning<br>* 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).<br>* Other names: vision training;|
| Experimental: Occlusion therapy<br>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. | Behavioral: Occlusion therapy<br>* 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).<br>* Other names: vision therapy;|
| Experimental: Video game<br>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). | Behavioral: Video Games<br>* 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).<br>* Other names: vision training;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Amblyopic vision | Improvement in amblyopic vision : visual acuity and stereoacuity | 9 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Spatial vision | Improvement in spatial vision (eg. contrast sensitivity, positional acuity and spatial attention) | 9 months | 
| Temporal vision | Improvement in temporal processing and temporal vision | 9 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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amblyopia treatment, neural plasticity, perceptual learning, vision therapy, spatial vision, video games, occlusion therapy