Stochastic Resonance Applied to Amblyopia Training and the Plasticity of Brain
Condition: Amblyopia; Amblyopia, Anisometropic
MeSH terms: Amblyopia
Study type: Interventional

Summary: 
      The prevalence of Taiwan's population with amblyopia is 2-5%. Amblyopia affects the daily
      life and learning ability. The human visual system can be developed normally with exposure of
      clear images on the retina, which often drive the development and projection of optic nerves
      progressively. In general, the visual acuity progresses gradually with age. A normal vision
      is relatively mature until 8 years old. Several types of amblyopia (strabismic amblyopia,
      refractive amblyopia, and deprivation amblyopia) are identified. The refractive amblyopia and
      deprivation amblyopia must be corrected by wearing glasses or surgeries. Otherwise, amblyopia
      is often corrected by occlusion of the dominant eye or amblyopia training. The Cambridge
      Stimulator (CAM) with rotating grating is commonly used in clinic in Taiwan. The principle of
      the CAM allows subjects to draw pictures on the plate in coincidence with occlusion of the
      dominant eye. The parents have to go with their children to a hospital weekly. The CAM
      training is a stereotyped visuomotor behavior, which usually causes fatigue and uninteresting
      results for children.

      Recently, some computer games have been incorporated with CAM training. However, their
      clinical impact on amblyopia is largely unknown. Moreover, most of studies don't have
      long-term tracking, and they only use limited assessments. In this project, a home-based
      training would be built for children with amblyopia. A CAM training with a hierarchical
      structure with story-based organization would be implemented in the tablet. It will save time
      for children and parents for traffic between the home and hospital. The CAM training with
      organized structure would increase acceptability and create subjects' motivation for
      long-term training. In addition, a stochastic resonance theory would be incorporated with the
      CAM training to potentiate the learning curve of a visuomotor skill in young children. Five
      systematic assessments, including visual acuity, grating acuity, contrast sensitivity, and 2
      measurements of visual evoked potentials (VEPs), would be used. The investigators
      hypothesized that the rotating grating stimulation and stochastic resonance stimulation
      groups showed significant enhancement of the visual functions compared with the control group
      and performance of the VEPs toward better eye through the home-based training apparatus.
    


Intervention name(s): Portable tablet
Intervention type(s): Device
Intervention description(s): Each training session was limited to 15 minutes a day, 5 days a week. The entire training period was 6 months.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Treatment
Keywords: Amblyopia; Amblyopic training; Contrast sensitivity; Grating acuity; Stochastic resonance; Visual acuity; Visual evoked potential