Spatial pattern summation is phase-insensitive in the fovea but not in the periphery.

We measured the effect of phase coherence on the detectability of a chain of Gabor patches. The stimuli were elongated patterns consisting of 1-8 vertical Gabor patches, aligned vertically and either in phase or 180 deg out of phase from their immediate neighbors. In the fovea, the phase configuration had no effect on detection threshold, suggesting a full-wave rectification operation mediating foveal spatial summation. At 5 deg in the periphery, detection thresholds for the in-phase configuration were lower than those for the alternating-phase configuration, to an extent compatible with a half-wave rectification operation mediating peripheral spatial summation.

[1]  S. Lehmkuhle,et al.  An oblique effect of spatial summation , 1983, Vision Research.

[2]  U. Polat,et al.  What pattern the eye sees best , 1999, Vision Research.

[3]  A. Watson,et al.  Quest: A Bayesian adaptive psychometric method , 1983, Perception & psychophysics.

[4]  F. Campbell,et al.  The effect of phase on the perception of compound gratings. , 1974, Vision research.

[5]  M. C. Lawden,et al.  An investigation of the ability of the human visual system to encode spatial phase relationships , 1983, Vision Research.

[6]  David Whitaker,et al.  Effects of luminance and external temporal noise on flicker sensitivity as a function of stimulus size at various eccentricities , 1994, Vision Research.

[7]  U. Polat,et al.  Lateral interactions between spatial channels: Suppression and facilitation revealed by lateral masking experiments , 1993, Vision Research.

[8]  Bettina L. Beard,et al.  Vernier Acuity with Non-simultaneous Targets: The Cortical Magnification Factor Estimated by Psychophysics , 1997, Vision Research.

[9]  David J. Field,et al.  Contour integration by the human visual system: Evidence for a local “association field” , 1993, Vision Research.

[10]  Ingo Rentschler,et al.  Loss of spatial phase relationships in extrafoveal vision , 1985, Nature.

[11]  R. Watt,et al.  A theory of the primitive spatial code in human vision , 1985, Vision Research.

[12]  A. Gorea,et al.  Different encoding mechanisms for phase and contrast , 1986, Vision Research.

[13]  R. F. Hess,et al.  Evidence for spatially local computations underlying discrimination of periodic patterns in fovea and periphery , 1987, Vision Research.

[14]  D G Pelli,et al.  The VideoToolbox software for visual psychophysics: transforming numbers into movies. , 1997, Spatial vision.

[15]  J. Nachmias,et al.  Discrimination of simple and complex gratings , 1975, Vision Research.

[16]  O. J. Braddick,et al.  Discrimination of spatial phase shows a qualitative difference between foveal and peripheral processing , 1991, Vision Research.

[17]  S. Grossberg,et al.  Contour Integration Across Polarities and Spatial Gaps: From Local Contrast Filtering to Global Grouping , 1997, Vision Research.

[18]  R. W. Bowen Isolation and interaction of ON and OFF pathways in human vision: Pattern-polarity effects on contrast discrimination , 1995, Vision Research.

[19]  R. Hess,et al.  The functional area for summation to threshold for sinusoidal gratings , 1978, Vision Research.

[20]  S. Klein,et al.  Hyperacuity thresholds of 1 sec: theoretical predictions and empirical validation. , 1985, Journal of the Optical Society of America. A, Optics and image science.

[21]  D. Hubel,et al.  Receptive fields and functional architecture of monkey striate cortex , 1968, The Journal of physiology.

[22]  S. Klein,et al.  Vernier acuity, crowding and cortical magnification , 1985, Vision Research.

[23]  M. Banks,et al.  Sensitivity loss in odd-symmetric mechanisms and phase anomalies in peripheral vision , 1987, Nature.

[24]  L. Spillmann,et al.  A comparison of perceptive and receptive fields in man and monkey. , 1987, Human neurobiology.

[25]  M. Berkley,et al.  Contrast sensitivity for vertically and obliquely oriented gratings as a function of grating area , 1983, Vision Research.

[26]  C W Tyler,et al.  Mechanisms for dynamic stereomotion respond selectively to horizontal velocity components , 1995, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[27]  E H Adelson,et al.  Spatiotemporal energy models for the perception of motion. , 1985, Journal of the Optical Society of America. A, Optics and image science.

[28]  C W Tyler,et al.  The Morphonome image psychophysics software and a calibrator for Macintosh systems. , 1997, Spatial vision.

[29]  I. Ohzawa,et al.  Spatiotemporal organization of simple-cell receptive fields in the cat's striate cortex. I. General characteristics and postnatal development. , 1993, Journal of neurophysiology.

[30]  J. Robson,et al.  Probability summation and regional variation in contrast sensitivity across the visual field , 1981, Vision Research.

[31]  P. O. Bishop,et al.  Spatial vision. , 1971, Annual review of psychology.

[32]  Norma Graham,et al.  Nonlinear processes in spatial-frequency channel models of perceived texture segregation: Effects of sign and amount of contrast , 1992, Vision Research.

[33]  F A Bilsen,et al.  The influence of the number of cycles upon the visual contrast threshold for spatial sine wave patterns. , 1974, Vision research.

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

[35]  G. Sperling Three stages and two systems of visual processing. , 1989, Spatial vision.

[36]  J A Solomon,et al.  Model of visual contrast gain control and pattern masking. , 1997, Journal of the Optical Society of America. A, Optics, image science, and vision.

[37]  M. Banks,et al.  The effects of contrast, spatial scale, and orientation on foveal and peripheral phase discrimination , 1991, Vision Research.

[38]  H R Wilson,et al.  Curvature and separation discrimination at texture boundaries. , 1992, Journal of the Optical Society of America. A, Optics and image science.

[39]  C. Tyler,et al.  Bayesian adaptive estimation of psychometric slope and threshold , 1999, Vision Research.

[40]  D H Brainard,et al.  The Psychophysics Toolbox. , 1997, Spatial vision.

[41]  Steven C. Dakin,et al.  Absence of contour linking in peripheral vision , 1997, Nature.

[42]  J. M. Foley,et al.  Pattern detection in the presence of maskers that differ in spatial phase and temporal offset: threshold measurements and a model , 1999, Vision Research.

[43]  T. Caelli,et al.  Visual sensitivity to two-dimensional spatial phase. , 1982, Journal of the Optical Society of America.