Frequency-doubling illusion

The frequency-doubling illusion is an apparent doubling of spatial frequency when a sinusoidal grating is modulated rapidly in temporal counterphase.[1] Recently, it has been proposed that the illusion arises from a spatially nonlinear ganglion cell class.[2] The presence of this illusion therefore indicates abnormalities in the retina such as glaucoma.

A more recent study's results argue against the hypothesis that spatially nonlinear retinal ganglion cells are the physiological substrate of the frequency-doubling illusion. A cortical loss of temporal phase discrimination may be the principal cause of the illusion, whereas spatial phase information (i.e., grating position) is retained.[3]

Sensitivity to the spatial-frequency-doubling illusion was also positively correlated with reading lag and coherent motion. The results provide good support for a magno deficit in dyslexia that has its origins at a retinal level with impairment in—at least partially—M(y)-cell activity.[4]

References

  1. ↑ Sun, H., Lee, B. B., White, A. J. R., Swanson, W. H., (2002). Examination of mechanisms underlying the frequency-doubling illusion. Journal of Vision, Volume 2, Number 10, Abstract 9, Page 9a
  2. ↑ Maddess, T., Goldberg, I., Dobinson, J., Wine, S., Welsh, A.H. & James, A.C. (1999). Testing for glaucoma with the spatial frequency doubling illusion. Vision Research, 39, 4258-4273.g
  3. ↑ Sun, H., Lee, B. B., White, A. J. R., Swanson, W. H., (2002).Examination of mechanisms underlying the frequency-doubling illusion. Journal of Vision, Volume 2, Number 10, Abstract 9, Page 9a
  4. ↑ Perception ECVP 2001
This article is issued from Wikipedia - version of the 4/30/2015. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.