Peripheral positional acuity: Retinal and cortical constraints on 2-dot separation discrimination under photopic and scotopic conditions

The precision of discriminating the separation of two dots was measured as a function of separation for eccentricities of 0-10 deg under photopic and scotopic conditions. At each eccentricity, the 2-dot separation discrimination thresholds showed a V-shaped dependence on separation. For separations less than approximately twice the resolution threshold, performance deteriorated from photopic to scotopic conditions and appeared to be limited by ganglion cell receptive field size or spacing. For separations smaller than 10% of the effective eccentricity (eccentricity + 0.6 deg), the photopic 2-dot separation discrimination thresholds were significantly better than 3-dot bisection thresholds previously measured under similar experimental conditions, supporting the hypothesis that 3-dot bisection suffers from spatial interference for these separations. Interestingly, under scotopic conditions, 2-dot separation discrimination thresholds were better than resolution for a range of separations at each eccentricity, implying that cone input was not necessary for hyperacuity performance. 2-dot separation discrimination thresholds for large separations were little changed from photopic to scotopic luminance conditions.

[1]  L L SLOAN,et al.  Peripheral visual acuity with special reference to scotopic illumination. , 1947, American journal of ophthalmology.

[2]  Hugh R. Wilson,et al.  Responses of spatial mechanisms can explain hyperacuity , 1986, Vision Research.

[3]  S P McKee,et al.  Interference with line-orientation sensitivity. , 1976, Journal of the Optical Society of America.

[4]  H. Bedell,et al.  Precision and accuracy of oculocentric direction for targets of different luminances , 1985, Perception & psychophysics.

[5]  J J Koenderink,et al.  Perimetry of contrast detection thresholds of moving spatial sine wave patterns. IV. The influence of the mean retinal illuminance. , 1978, Journal of the Optical Society of America.

[6]  P. R. Bevington,et al.  Data Reduction and Error Analysis for the Physical Sciences , 1969 .

[7]  F. Newell.  The American Journal of Ophthalmology , 1862, American journal of ophthalmology.

[8]  Gerald Westheimer.  The oscilloscopic view: Retinal illuminance and contrast of point and line targets , 1985, Vision Research.

[9]  C. A. Burbeck,et al.  Exposure-duration effects in localization judgments. , 1986, Journal of the Optical Society of America. A, Optics and image science.

[10]  Lothar Spillmann,et al.  Perceptive field size in fovea and periphery of the light- and dark-adapted retina , 1980, Vision Research.

[11]  J. Rovamo,et al.  Cortical magnification factor predicts the photopic contrast sensitivity of peripheral vision , 1978, Nature.

[12]  J. Koenderink,et al.  Scale invariant features of differential spatial displacement discrimination , 1987, Vision Research.

[13]  S. Klein,et al.  Positional uncertainty in peripheral and amblyopic vision , 1987, Vision Research.

[14]  P. Lennie,et al.  Shared pathways for rod and cone vision , 1986, Vision Research.

[15]  D M Levi,et al.  Peripheral hyperacuity: three-dot bisection scales to a single factor from 0 to 10 degrees. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[16]  F. Campbell,et al.  Differences in the neural basis of human amblyopias: The effect of mean luminance , 1980, Vision Research.

[17]  M J Morgan,et al.  Spatial and spatial-frequency primitives in spatial-interval discrimination. , 1985, Journal of the Optical Society of America. A, Optics and image science.

[18]  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.

[19]  J. Hirsch,et al.  Spatial-frequency discrimination at low frequencies: evidence for position quantization by receptive fields. , 1985, Journal of the Optical Society of America. A, Optics and image science.

[20]  John H. R. Maunsell,et al.  The visual field representation in striate cortex of the macaque monkey: Asymmetries, anisotropies, and individual variability , 1984, Vision Research.

[21]  R Näsänen,et al.  Cortical magnification and peripheral vision. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[22]  D. Williams,et al.  Cone spacing and the visual resolution limit. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[23]  L. Thibos,et al.  Retinal limits to the detection and resolution of gratings. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[24]  S. Klein,et al.  Position sense of the peripheral retina. , 1987, Journal of the Optical Society of America. A, Optics and image science.

[25]  G. Westheimer,et al.  Spatial location and hyperacuity: The centre/surround localization contribution function has two substrates , 1985, Vision Research.

[26]  M. A. Bouman,et al.  Psychophysical experiments on spatial summation at threshold level of the human peripheral retina , 1977, Vision Research.

[27]  Stanley J. Schein.  Neural magnifications and visual performance (A) , 1987 .

[28]  H. P. Snippe,et al.  Effects of blur and eccentricity on differential spatial displacement discrimination , 1988, Vision Research.

[29]  H. W. Leibowitz,et al.  Radial Localization of a Single Stimulus as a Function of Luminance and Duration of Exposure , 1955 .

[30]  J Hirsch,et al.  Limits of spatial-frequency discrimination as evidence of neural interpolation. , 1982, Journal of the Optical Society of America.

[31]  G Westheimer,et al.  Editorial: Visual acuity and hyperacuity. , 1975, Investigative ophthalmology.

[32]  Gerald Westheimer,et al.  Temporal and spatial interference with vernier acuity , 1975, Vision Research.

[33]  C. A. Burbeck.  Position and spatial frequency in large-scale localization judgments , 1987, Vision Research.

[34]  E. Switkes,et al.  Deoxyglucose analysis of retinotopic organization in primate striate cortex. , 1982, Science.

[35]  Dennis M. Levi,et al.  “Weber's law” for position: Unconfounding the role of separation and eccentricity , 1988, Vision Research.

[36]  G. Westheimer.  The spatial grain of the perifoveal visual field , 1982, Vision Research.

[37]  N. Drasdo.  The neural representation of visual space , 1977, Nature.

[38]  F. W. Weymouth.  Visual sensory units and the minimal angle of resolution. , 1958, American journal of ophthalmology.

[39]  Dennis M. Levi,et al.  The role of separation and eccentricity in encoding position , 1990, Vision Research.

[40]  G. Westheimer,et al.  Spatial location and hyperacuity: flank position within the centre and surround zones. , 1985, Spatial vision.

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