Is Fourier analysis performed by the visual system or by the visual investigator.

A numerical Fourier transform was made of the pincushion grid illusion and the spectral components orthogonal to the illusory lines were isolated. Their inverse transform creates a picture of the illusion. The spatial-frequency response of cortical, simple receptive field neurons similarly filters the grid. A complete set of these neurons thus approximates a two-dimensional Fourier analyzer. One cannot conclude, however, that the brain actually uses frequency-domain information to interpret visual images.

[1]  A L Ochs,et al.  Two-dimensional analysis of retinal information transfer. , 1975, Journal of the Optical Society of America.

[2]  P. Schiller,et al.  Quantitative studies of single-cell properties in monkey striate cortex. II. Orientation specificity and ocular dominance. , 1976, Journal of neurophysiology.

[3]  P. Schiller,et al.  Quantitative studies of single-cell properties in monkey striate cortex. III. Spatial frequency. , 1976, Journal of neurophysiology.

[4]  C Blakemore,et al.  On the existence of neurones in the human visual system selectively sensitive to the orientation and size of retinal images , 1969, The Journal of physiology.

[5]  P. Schiller,et al.  Quantitative studies of single-cell properties in monkey striate cortex. I. Spatiotemporal organization of receptive fields. , 1976, Journal of neurophysiology.

[6]  G. Legge.  Adaptation to a spatial impulse: Implications for Fourier transform models of visual processing , 1976, Vision Research.

[7]  R. Schachar,et al.  The "pincushion grid" illusion. , 1976, Science.

[8]  J. Robson,et al.  Application of fourier analysis to the visibility of gratings , 1968, The Journal of physiology.

[9]  C. Enroth-Cugell,et al.  The contrast sensitivity of retinal ganglion cells of the cat , 1966, The Journal of physiology.

[10]  A Pantle,et al.  Size-Detecting Mechanisms in Human Vision , 1968, Science.

[11]  Contour enhancement of two-dimensional figures observed in the lateral geniculate cells of cats. , 1974, Vision research.

[12]  I. D. Macleod,et al.  The visibility of gratings: spatial frequency channels or bar-detecting units? , 1974, Vision research.

[13]  S. W. Kuffler.  Discharge patterns and functional organization of mammalian retina. , 1953, Journal of neurophysiology.

[14]  D. H. Kelly,et al.  Pattern detection and the two-dimensional fourier transform: Circular targets , 1975, Vision Research.

[15]  M. L Rudee,et al.  Optical transforms and the "pincushion grid" illusion? , 1977, Science.

[16]  B. Julesz,et al.  Spatial-frequency masking in vision: critical bands and spread of masking. , 1972, Journal of the Optical Society of America.

[17]  L. Maffei,et al.  The visual cortex as a spatial frequency analyser. , 1973, Vision research.

[18]  Michael Shantz,et al.  The bipolar cell , 1976, Vision Research.

[19]  D. Hubel,et al.  Receptive fields, binocular interaction and functional architecture in the cat's visual cortex , 1962, The Journal of physiology.

[20]  P. O. Bishop,et al.  Interaction effects of visual contours on the discharge frequency of simple striate neurones , 1971, The Journal of physiology.

[21]  P. Suppes,et al.  Contemporary Developments in Mathematical Psychology , 1976 .

[22]  G. F. Cooper,et al.  The spatial selectivity of the visual cells of the cat , 1969, The Journal of physiology.