Amblyopic Quasi-blindness for Image Structure
by , , , ,
Abstract:
Human amblyopes display reduced contrast sensitivities, suffer from perceptual distortion, and their letter acuities are worse than is predicted from grating visibility. We sought the origin of these dysfunctions by measuring normal and amblyopic sensitivities to various forms of well-defined image distortion, namely band-limited phase quantization, phase quantization with additional amplitude modulation, and grey-scale modification. Our results prove the existence of an amblyopic quasi-blindness to image structure, that cannot be explained in terms of contrast detection. We discuss these findings within the computational scheme of image decomposition into local amplitude and local phase values. They are consistent with the assumption of amblyopic eyes being impaired in processing local phase but having the local amplitude (or energy, possibly at reduced gain) at their disposal. Phrased in physiological terms, we propose a scheme of complex-cells-only vision in amblyopia. We also provide a demonstration of how amblyopic eyes may see the test stimuli and natural images by generating local amplitude and phase representations at limited phase resolution.
Reference:
Amblyopic Quasi-blindness for Image Structure (BERNHARD TREUTWEIN, INGO RENTSCHLER, CHRISTOPH ZETZSCHE, MARGIT SCHEIDLER, KLAUS-PETER BOERGEN), In Vision Research, Elsevier BV, volume 36, 1996.
Bibtex Entry:
@Article{TREUTWEIN1996,
  author    = {BERNHARD TREUTWEIN and INGO RENTSCHLER and CHRISTOPH ZETZSCHE and MARGIT SCHEIDLER and KLAUS-PETER BOERGEN},
  title     = {Amblyopic Quasi-blindness for Image Structure},
  journal   = {Vision Research},
  year      = {1996},
  volume    = {36},
  number    = {14},
  pages     = {2211--2228},
  month     = {jul},
  abstract  = {Human amblyopes display reduced contrast sensitivities, suffer from perceptual distortion, and their letter acuities are worse than is predicted from grating visibility. We sought the origin of these dysfunctions by measuring normal and amblyopic sensitivities to various forms of well-defined image distortion, namely band-limited phase quantization, phase quantization with additional amplitude modulation, and grey-scale modification. Our results prove the existence of an amblyopic quasi-blindness to image structure, that cannot be explained in terms of contrast detection. We discuss these findings within the computational scheme of image decomposition into local amplitude and local phase values. They are consistent with the assumption of amblyopic eyes being impaired in processing local phase but having the local amplitude (or energy, possibly at reduced gain) at their disposal. Phrased in physiological terms, we propose a scheme of complex-cells-only vision in amblyopia. We also provide a demonstration of how amblyopic eyes may see the test stimuli and natural images by generating local amplitude and phase representations at limited phase resolution.},
  doi       = {10.1016/0042-6989(95)00312-6},
  publisher = {Elsevier {BV}},
  url       = {10.1016/0042-6989(95)00312-6">http://dx.doi.org/10.1016/0042-6989(95)00312-6},
}