Intensity-dependent spatial summation.

Psychophysical evidence indicates that, in the human retina, the size of the spatial-summation area decreases as illuminance increases. Such a relationship would be beneficial for the detection of spatial contrast in the presence of photon noise. We analyze an image-processing mechanism in which the area of a strictly positive point-spread function varies inversely with local illuminance while its volume remains constant. In addition to its expected effect of improving spatial resolution as illuminance increases, this mechanism also yields center-surround antagonism and all other manifestations of bandpass filtering and accounts for Ricco's law and Weber's law--including the failures of both laws as a function of test conditions. The relationship between this mechanism and lateral inhibition is analyzed.

[1]  The Nervous System in Anæmia , 1902, The Hospital.

[2]  S. Hecht.  THE RELATION BETWEEN VISUAL ACUITY AND ILLUMINATION , 1928, The Journal of general physiology.

[3]  S. Shlaer.  THE RELATION BETWEEN VISUAL ACUITY AND ILLUMINATION , 1937, The Journal of general physiology.

[4]  B. H. Crawford.  Visual adaptation in relation to brief conditioning stimuli , 1947, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[5]  A. Rose.  The sensitivity performance of the human eye on an absolute scale. , 1948, Journal of the Optical Society of America.

[6]  W. Stiles,et al.  Saturation of the Rod Mechanism of the Retina at High Levels of Stimulation , 1954 .

[7]  H B BARLOW,et al.  Increment thresholds at low intensities considered as signal/noise discriminations , 1957, The Journal of physiology.

[8]  H. Barlow,et al.  Change of organization in the receptive fields of the cat's retina during dark adaptation , 1957, The Journal of physiology.

[9]  H. Barlow.  Temporal and spatial summation in human vision at different background intensities , 1958, The Journal of physiology.

[10]  R. Jones,et al.  Quantum efficiency of human vision. , 1959, Journal of the Optical Society of America.

[11]  J. Krauskopf.  Effect of retinal image stabilization on the appearance of heterochromatic targets. , 1963, Journal of the Optical Society of America.

[12]  D. Jameson,et al.  Mach bands : quantitative studies on neural networks in the retina , 1966 .

[13]  V. Glezer.  The receptive fields of the retina. , 1965, Vision research.

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

[15]  M. A. Bouman,et al.  Spatial Modulation Transfer in the Human Eye , 1967 .

[16]  B. Sakitt.  Configuration dependence of scotopic spatial summation , 1971, The Journal of physiology.

[17]  D. H. Kelly.  Adaptation effects on spatio-temporal sine-wave thresholds. , 1972, Vision research.

[18]  F. Campbell,et al.  The contrast sensitivity of the cat , 1973, The Journal of physiology.

[19]  J. Bergen,et al.  A four mechanism model for threshold spatial vision , 1979, Vision Research.

[20]  D Marr,et al.  Theory of edge detection , 1979, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[21]  William H. Merigan,et al.  The luminance dependence of spatial vision in the cat , 1981, Vision Research.