The frequency-doubling illusion is an apparent doubling of spatial frequency when a sinusoidal grating is modulated rapidly in temporal counterphase.Kelly, D.H. (1981) Nonlinear visual responses to flickering sinusoidal gratings. Journal of the Optical Society of America, 71, 1051-1055Sun, 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 Recently, it has been proposed that the illusion arises from a spatially nonlinear ganglion cell class.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 The contrast threshold values needed for perceiving this physiological effect are used in frequency doubling technology perimetry for the detection of even early phases of glaucoma.Cello, K.E., Nelson-Quigg, J.M. & Johnson, C.A. (2000). Frequency doubling technology perimetry for detection of glaucomatous field loss. American Journal of Ophthalmology, 129, 314-322Quigley, H.A. (1998). Identification of glaucoma-related visual field abnormality with the screening protocol of frequency doubling technology. American Journal of Ophthalmology, 125, 819-829Burnstein, Y., Ellish, N.J., Magbalon, M. & Higginbotham, E.J. (2000). Comparison of frequency doubling perimetry with humphrey visual field analysis in a glaucoma practice. American Journal of Ophthalmology, 129, 328-333 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 pathway of temporal phase discrimination may be the principal cause of the illusion, whereas spatial phase information (i.e., grating position) is retained.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
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.
References