Establishing New Treatment Approaches for Amblyopia: Perceptual Learning and Video Games

Not Applicable

Recruiting

• Conditions: Amblyopia
• Interventions: Behavioral: Occlusion Therapy; Behavioral: Perceptual Learning; Behavioral: Video Game Vision Training

• Registration Number: NCT05522972
• Lead Sponsor: Nova Southeastern University

Brief Summary

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

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 Publications) 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.

Study Timeline

• Study First Submitted: 2022-08-24
• Study First Submitted QC: 2022-08-29
• Study First Posted: 2022-08-31
• Study Start: 2022-09-13
• Status Verified: 2024-11
• Last Update Submitted: 2024-11-13
• Last Update Posted: 2024-11-15
• Primary Completion: 2029-08-31
• Study Completion: 2029-08-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 180

Inclusion Criteria

• adults and children with normal vision or amblyopia
• amblyopia: interocular VA difference of 0.1 logMAR or more

Exclusion Criteria

• any ocular pathological conditions, nystagmus

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Occlusion therapy	Occlusion Therapy	Participants will be required to cover the dominant eye during the day in order to push the brain to use the fellow amblyopic eye: 1-2 hrs per session, 4-5 sessions/week for \~1-6 months
Perceptual learning	Perceptual Learning	Participants will be required to practice a visual discrimination task (e.g. visual acuity, position acuity, contrast sensitivity, \& stereoacuity) for a period of time: 1-2 hrs per session, 4-5 sessions/week for \~1-6 months
Video Games	Video Game Vision Training	Participants will be required to play video games for a period of time: 1-2 hrs per session, 4-5 sessions/week for \~1-6 months

Primary Outcome Measures

Name	Time	Method
Change in visual acuity before and after the intervention	9 months	"Visual acuity", the gold standard for vision testing, will be measured. Participants will be asked to read letters on a LogMAR letter chart. The smallest letters that can be read correspond to visual acuity (e.g., Snellen acuity of 20/20, letter-stroke width = 1 minute of arc).
Change in stereoacuity before and after the intervention	9 months	"Stereoacuity" will be measured psychophysically using a new stereoacuity function test (1.25, 2.5, 5, 10, 15, \& 20 cycles per degree) developed in our previous studies (Li et al 2016). A custom-built 4-mirror haploscope will be used to present a stereogram to each eye. Stereoacuity is the smallest stereo disparity that can be seen in binocular vision (in the unit of seconds of arc, arcsec).; The conventional stereoacuity tests (including Randot Stereoacuity Test, Stereofly Test \& Preschool Stereo Test) will also be used to measure stereoacuity. Participants will be asked to wear a pair of 3D glasses and to identify the target 3D pictures at various 3D levels. The smallest 3D disparities that can be seen correspond to stereoacuity (e.g. normal range of stereoacuity: 50 seconds of arc or better).

Secondary Outcome Measures

Name	Time	Method
Change in contrast sensitivity before and after the intervention	9 months	"Contrast sensitivity", the ability to detect low contrast / brightness, will be measured psychophysically for a range of spatial frequencies (1.25, 2.5, 5, 10, \& 20 cycles per degree). Visual stimuli at different contrast levels will be displayed on a monitor screen. The smallest detectable stimulus contrast level will be measured in the unit of cd/m2.
Change in positional (or Vernier) acuity before and after the intervention	9 months	"Positional acuity", the ability to detect a subtle positional offset between visual stimuli, will be measured psychophysically. Visual stimuli with different amount of positional offsets will be displayed on a monitor screen. The smallest detectable stimulus offset will be measured as position acuity, in the unit of seconds of arc.

Trial Locations

Locations (1)

Nova Southeastern University College of Optometry; 🇺🇸 Fort Lauderdale, Florida, United States