Amblyopia is a developmental visual disorder characterized by abnormal form vision and binocular functions. Past research has differentiated the performance of subjects with strabismic and anisometropic subtypes of amblyopia.
1-6 Often the motivation is to better understand the pathogenesis of amblyopia. An important source of evidence is monocular position acuity tasks. For example, Vernier acuity loss is more severe in subjects with strabismus compared with that in subjects with anisometropia. In subjects with strabismus, the deficit is larger than that predicted by linearly scaling their grating acuity,
5 indicating that additional deficits are involved. Different models attribute this acuity loss according to the size, shape, or density of receptive fields in the visual cortex, or to spatial disarray in their topographical location.
2,7-9 In general, these models suggest that abnormal “noise” arises in the visual cortex, probably in areas beyond the primary visual cortex.