Institute Homepage DE Sign In

Back

Empirical Inference Article 2002

Contrast discrimination with sinusoidal gratings of different spatial frequency

Thumb ticker sm thumb felix a. wichmann
Empirical Inference
Felix A. Wichmann
  • Research Scientist

The detectability of contrast increments was measured as a function of the contrast of a masking or “pedestal” grating at a number of different spatial frequencies ranging from 2 to 16 cycles per degree of visual angle. The pedestal grating always had the same orientation, spatial frequency and phase as the signal. The shape of the contrast increment threshold versus pedestal contrast (TvC) functions depend of the performance level used to define the “threshold,” but when both axes are normalized by the contrast corresponding to 75% correct detection at each frequency, the (TvC) functions at a given performance level are identical. Confidence intervals on the slope of the rising part of the TvC functions are so wide that it is not possible with our data to reject Weber’s Law.

Author(s): Bird, CM. and Henning, GB. and Wichmann, FA.
Journal: Journal of the Optical Society of America A
Volume: 19(7)
Pages: 1267-1273
Year: 2002
Day: 0
Bibtex Type: Article (article)
Digital: 0
Electronic Archiving: grant_archive
Organization: Max-Planck-Gesellschaft
School: Biologische Kybernetik
Links:

BibTex 

@article{1138,
  title = {Contrast discrimination with sinusoidal gratings of different spatial frequency},
  journal = {Journal of the Optical Society of America A},
  abstract = {The detectability of contrast increments was measured as a function of the contrast of a masking or “pedestal” grating at a number of different spatial frequencies ranging from 2 to 16 cycles per degree of visual angle. The pedestal grating always had the same orientation, spatial frequency and phase as the signal. The shape of the contrast increment threshold versus pedestal contrast (TvC) functions depend of the performance level used to define the “threshold,” but when both axes are normalized by the contrast corresponding to 75% correct detection at each frequency, the (TvC) functions at a given performance level are identical. Confidence intervals on the slope of the rising part of the TvC functions are so wide that it is not possible with our data to reject Weber’s Law.},
  volume = {19(7)},
  pages = {1267-1273},
  organization = {Max-Planck-Gesellschaft},
  school = {Biologische Kybernetik},
  year = {2002},
  slug = {1138},
  author = {Bird, CM. and Henning, GB. and Wichmann, FA.}
}