Perceptual learning improves contrast sensitivity and visual acuity in adults with anisometropic amblyopia

Vision Research Lab, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui. zhouy@ustc.educn
Vision Research (Impact Factor: 1.82). 04/2006; 46(5):739-50. DOI: 10.1016/j.visres.2005.07.031
Source: PubMed


To evaluate the effects of perceptual learning on contrast-sensitivity function and visual acuity in adult observers with amblyopia, 23 anisometropic amblyopes with a mean age of 19.3 years were recruited and divided into three groups. Subjects in Group I were trained in grating detection in the amblyopic eye near pre-training cut-off spatial frequency. Group II received a training regimen of repeated contrast-sensitivity function measurements in the amblyopic eye. Group III received no training. We found that training substantially improved visual acuity and contrast-sensitivity functions in the amblyopic eyes of all the observers in Groups I and II, although no significant performance improvement was observed in Group III. For observers in Group I, performance improvements in the amblyopic eyes were broadly tuned in spatial frequency and generalized to the fellow eyes. The latter result was not found in Group II. In a few cases tested, improvements in visual acuity following training showed about 90% retention for at least 1 year. We concluded that the visual system of adult amblyopes might still retain substantial plasticity. Perceptual learning shows potential as a clinical tool for treating child and adult amblyopia.

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Available from: Zhong-Lin Lu, Mar 27, 2014
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    • "g . , amblyopes ( Huang , Tao , Zhou , & Lu , 2007 ; Xu , Lu , Qiu , & Zhou , 2006 ) , training at the cutoff spatial frequency mainly decreases the elevated internal noise ( Huang et al . , 2009 ) , triggering substan - tial improvement in visual acuity and broad transfer to untrained spatial frequencies ( Huang et al . "
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    • "The AUCSF characterizes spatial vision over a wide range of spatial frequencies (Lesmes et al., 2010; van Gaalen et al., 2009). The cutoff spatial frequency characterizes the spatial resolution limit of the visual system (Campbell & Green, 1965; Hou et al., 2010; Regan et al., 1981; Zhou et al., 2006). Visual acuity and cutoff spatial frequency were highly correlated in all the test conditions (Pearson Correlation, R = À0.717, "
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