Abstract

The data presented in this paper examine the ability of observers to detect a modulation in the contrast of chromatic and luminance gratings as a function of the carrier contrast, duration, and spatial frequency. The nature of the signal underlying this ability is investigated by examining both the paradigm used to make the measurement and the effect of grating masks on performance in the tasks. The results show that observers’ ability to discriminate amplitude modulation from an unmodulated carrier is dependent on carrier contrast but only up to 58 times carrier-detection threshold. Discrimination is, however, independent of spatial frequency [10–1 cycles per degree (cpd) component-frequency range], carrier color, and, most surprisingly, stimulus duration (1000–30 ms). This set of experiments compliments data from previous papers and assimilates many of the conclusions drawn from this previous data. There is absolutely no evidence for the existence of a distortion product mediating performance under any of the current conditions, and the data seriously question whether the visual system might use such a signal even if it does exist under more extreme conditions than those used here. The evidence suggests that the visual system detects variations in both chromatic and luminance contrast by means of a mechanism operating locally upon the spatial structure of the carrier.

© 1998 Optical Society of America

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1998 (1)

C. L. Baker, J. C. Boulton, K. T. Mullen, “A nonlinear chromatic motion mechanism,” Vision Res. 38, 291–302 (1998).
[CrossRef] [PubMed]

1997 (7)

C. P. Benton, A. Johnston, P. W. McOwan, “Perception of motion direction in luminance- and contrast-defined reversed-phi motion sequences,” Vision Res. 37, 2381–2399 (1997).
[CrossRef] [PubMed]

S. J. Cropper, S. T. Hammett, “Adaptation to motion of a second order pattern: the motion aftereffect is not a general result,” Vision Res. 37, 2247–2259 (1997).
[CrossRef] [PubMed]

S. J. Cropper, S. T. Hammett, “Adaptation to motion of a second order pattern: the motion aftereffect is not a general result,” Vision Res. 37, 2247–2259 (1997).
[CrossRef] [PubMed]

E. D. Lumer, G. M. Edelman, G. Tononi, “Neural dynamics in a model of the thalamocortical system. I. Layers, loops and the emergence of fast synchronous rhythms,” Cereb. Cortex 7, 207–227 (1997).
[CrossRef] [PubMed]

E. D. Lumer, G. M. Edelman, G. Tononi, “Neural dynamics in a model of the thalamocortical system. II. The role of neural synchrony tested through perturbations of spike timing,” Cereb. Cortex 7, 228–236 (1997).
[CrossRef] [PubMed]

J. Nachmias, “How is a grating detected on a narrow-band masker?,” Invest. Ophthalmol. Visual Sci. 38, 3385 (1997).

F. A. Wichmann, “Masking by plaid patterns is not explained by adaptation, simple contrast gain-control or distortion products,” Invest. Ophthalmol. Visual Sci. 38, 2949 (1997).

1996 (5)

J. Wray, G. M. Edelman, “A model of color vision based on cortical reentry,” Cereb. Cortex 6, 701–716 (1996).
[CrossRef] [PubMed]

S. J. Cropper, A. M. Derrington, “Detection and motion detection in chromatic and luminance beats,” J. Opt. Soc. Am. A 13, 401–407 (1996).
[CrossRef]

H. S. Smallman, J. M. Harris, “Nonlinear visual distortion: an effective expansive nonlinearity from assymetry in ON and OFF pathways,” Invest. Ophthalmol. Visual Sci. Suppl. 37, 232 (1996).

S. J. Cropper, K. T. Mullen, D. R. Badcock, “Motion coherence across cardinal axes,” Vision Res. 36, 2475–2488 (1996).
[CrossRef] [PubMed]

Y. Chen, H. E. Bedell, L. J. Frishman, “Temporal-contrast discrimination and its neural correlates,” Perception 25, 505–522 (1996).
[CrossRef] [PubMed]

1995 (8)

H. Akutsu, G. E. Legge, “Discrimination of compound gratings: spatial frequency channels or local features?,” Vision Res. 35, 2685–2695 (1995).
[CrossRef] [PubMed]

J. A. Solomon, G. Sperling, “1st- and 2nd-order motion and texture resolution in central and peripheral vision,” Vision Res. 35, 59–64 (1995).
[CrossRef] [PubMed]

C. F. I. Stromeyer, A. Chaparro, A. Tolias, R. E. Kronauer, “Equiluminant settings change markedly with temporal frequency,” Invest. Ophthalmol. Visual Sci. 36, 962 (1995).

J. M. Harris, H. S. Smallman, “Visual distortion products from an expansive non-linearity,” Perception 24, 126b (1995).

Z.-L. Lu, G. Sperling, “The functional architecture of human visual motion perception,” Vision Res. 35, 2697–2722 (1995).
[CrossRef] [PubMed]

H. S. Smallman, J. M. Harris, “Spatial-frequency selectivity of contrast-modulated masking,” Perception 24, 127b (1995).

S. J. Cropper, D. R. Badcock, “Perceived direction of motion: it takes all orientations,” Perception 24, 106 (1995).

J. G. Daugman, C. J. Dowling, “Demodulation, predictive coding, and spatial vision,” J. Opt. Soc. Am. A 12, 641–660 (1995).
[CrossRef]

1994 (8)

S. J. Cropper, D. R. Badcock, A. Hayes, “On the role of second-order signals in the perceived direction of motion of type II plaid patterns,” Vision Res. 34, 2609–2612 (1994).
[CrossRef] [PubMed]

S. J. Cropper, A. M. Derrington, “Motion of chromatic stimuli: first-order or second-order?” Vision Res. 34, 49–58 (1994).
[CrossRef] [PubMed]

T. Ledgeway, “Adaptation to second-order motion results in a motion aftereffect for directionally ambiguous test stimuli,” Vision Res. 34, 2879–2889 (1994).
[CrossRef] [PubMed]

T. Ledgeway, A. T. Smith, “Evidence for separate motion-detecting mechanisms for first- and second-order motion in human vision,” Vision Res. 34, 2727–2740 (1994).
[CrossRef] [PubMed]

I. E. Holliday, S. J. Anderson, “Different processes underlie the detection of second-order motion at low and high temporal frequencies,” Proc. R. Soc. London Ser. B 257, 165–173 (1994).
[CrossRef]

A. Chaparro, C. F. Stromeyer, R. E. Kronauer, R. T. Eskew, “Separable red–green and luminance detectors for small flashes,” Vision Res. 34, 753–761 (1994).
[CrossRef]

S. J. Cropper, “Velocity discrimination in chromatic gratings and beats,” Vision Res. 34, 41–48 (1994).
[CrossRef] [PubMed]

H. R. Wilson, J. Kim, “Perceived motion in the vector-sum direction,” Vision Res. 34, 1835–1842 (1994).
[CrossRef] [PubMed]

1993 (8)

D. C. Burr, M. C. Morrone, “Impulse-response functions for chromatic and achromatic stimuli,” J. Opt. Soc. Am. A 10, 1706–1713 (1993).
[CrossRef]

A. Chaparro, C. F. Stromeyer, E. P. Huang, R. E. Kronauer, R. T. J. Eskew, “Colour is what the eye sees best,” Nature 361, 348–350 (1993).
[CrossRef] [PubMed]

Y. X. Zhou, C. L. J. Baker, “A processing stream in mammalian visual cortex for non-Fourier responses,” Science 261, 98–101 (1993).
[CrossRef] [PubMed]

J. Nachmias, “Masked detection of gratings: the standard model revisited,” Vision Res. 33, 1359–1365 (1993).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, G. B. Henning, “Discriminating the direction of second-order motion at short stimulus durations,” Vision Res. 33, 1785–1794 (1993).
[CrossRef] [PubMed]

J. C. Boulton, C. L. Baker, “Different parameters control motion perception above and below a critical density,” Vision Res. 33, 1803–1811 (1993).
[CrossRef] [PubMed]

J. C. Boulton, C. L. Baker, “Dependence on stimulus onset asynchrony in apparent motion: evidence for two mechanisms,” Vision Res. 33, 2013–2019 (1993).
[CrossRef] [PubMed]

D. Y. Teller, D. T. Lindsey, “Motion at isoluminance: motion dead zones in three-dimensional color space,” J. Opt. Soc. Am. A 10, 1324–1331 (1993).
[CrossRef] [PubMed]

1992 (4)

K. T. Mullen, J. C. Boulton, “Absence of smooth motion perception in color vision,” Vision Res. 32, 483–488 (1992).
[CrossRef] [PubMed]

D. I. A. MacLeod, D. R. Williams, W. Makous, “A visual non-linearity fed by single cones,” Vision Res. 32, 347–363 (1992).
[CrossRef] [PubMed]

H. R. Wilson, V. P. Ferrera, C. Yo, “A psychophysically motivated model for two-dimensional motion perception,” Visual Neurosci. 9, 79–97 (1992).
[CrossRef]

C. Yo, H. R. Wilson, “Perceived direction of moving two-dimensional patterns depends on duration, contrast and eccentricity,” Vision Res. 32, 135–147 (1992).
[CrossRef] [PubMed]

1990 (1)

D. T. Lindsey, D. Y. Teller, “Motion at isoluminance: discrimination/detection ratios for moving isoluminant gratings,” Vision Res. 30, 1751–1761 (1990).
[CrossRef] [PubMed]

1989 (5)

A. M. Derrington, G. B. Henning, “Some observations on the masking effects of two-dimensional stimuli,” Vision Res. 29, 241–246 (1989).
[CrossRef] [PubMed]

T. Ueno, W. H. Swanson, “Response pooling between chromatic and luminance systems,” Vision Res. 29, 325–334 (1989).
[CrossRef] [PubMed]

C. Chubb, G. Sperling, “Two motion perception mechanisms revealed through distance-driven reversal of apparent motion,” Proc. Natl. Acad. Sci. USA 86, 2985–2989 (1989).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacements of spatial beats: no role for distortion products,” Vision Res. 29, 731–739 (1989).
[CrossRef] [PubMed]

J. Nachmias, “Contrast modulated maskers: test of a late nonlinearity hypothesis,” Vision Res. 29, 137–142 (1989).
[CrossRef] [PubMed]

1988 (1)

1987 (4)

A. M. Derrington, “Distortion products in geniculate x-cells: a physiological basis for masking by spatially modulated gratings?” Vision Res. 27, 1377–1386 (1987).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacements of spatial beats: a monocular capability,” Vision Res. 27, 793–797 (1987).
[CrossRef] [PubMed]

R. F. Hess, J. S. Pointer, “Evidence for spatially local computations underlying discrimination of periodic patterns in fovea and periphery,” Vision Res. 27, 1343–1360 (1987).
[CrossRef] [PubMed]

N. Graham, J. G. Robson, “Summation of very close spatial frequencies: the importance of spatial probability summation,” Vision Res. 27, 1997–2007 (1987).
[CrossRef] [PubMed]

1986 (1)

A. M. Derrington, D. R. Badcock, “Detection of spatial beats: non-linearity or contrast increment detection?” Vision Res. 26, 343–348 (1986).
[CrossRef] [PubMed]

1985 (4)

D. R. Badcock, C. M. Schor, “Depth-increment detection function for individual spatial channels,” J. Opt. Soc. Am. A 2, 1211–1216 (1985).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacement of periodic patterns,” Vision Res. 25, 1253–1258 (1985).
[CrossRef] [PubMed]

K. T. Mullen, “The contrast sensitivity of human colour vision to red–green and blue–yellow chromatic gratings,” J. Physiol. (London) 359, 381–409 (1985).

A. M. Derrington, D. R. Badcock, “Separate detectors for simple and complex grating patterns?” Vision Res. 25, 1869–1878 (1985).
[CrossRef] [PubMed]

1984 (3)

V. C. Smith, R. W. Bowen, J. Pokorny, “Threshold temporal integration of chromatic stimuli,” Vision Res. 24, 653–660 (1984).
[CrossRef] [PubMed]

A. M. Derrington, J. Krauskopf, P. Lennie, “Chromatic mechanisms in lateral geniculate nucleus of macaque,” J. Physiol. (London) 357, 241–265 (1984).

P. Cavanagh, C. W. Tyler, O. E. Favreau, “Perceived velocity of moving chromatic gratings,” J. Opt. Soc. Am. A 1, 893–899 (1984).
[CrossRef] [PubMed]

1983 (2)

1982 (2)

J. H. T. Jamar, J. C. Campagne, J. J. Koenderink, “Detectability of amplitude- and frequency-modulation of suprathreshold sine-wave gratings,” Vision Res. 22, 407–416 (1982).
[CrossRef] [PubMed]

J. Krauskopf, D. R. Williams, D. W. Heeley, “Cardinal directions of color space,” Vision Res. 22, 1123–1131 (1982).
[CrossRef] [PubMed]

1981 (2)

D. G. Albrecht, R. L. DeValois, “Striate cortex responses to periodic patterns with and without the fundamental harmonics,” J. Physiol. (London) 319, 497–514 (1981).

G. E. Legge, “A power law for contrast discrimination,” Vision Res. 21, 457–467 (1981).
[CrossRef] [PubMed]

1980 (2)

R. L. Boynton, N. Kambe, “Chromatic difference steps of moderate size measured along theoretically critical axes,” Color Res. Appl. 5, 13–23 (1980).
[CrossRef]

G. E. Legge, J. M. Foley, “Contrast masking in human vision,” J. Opt. Soc. Am. 49, 1458–1471 (1980).
[CrossRef]

1978 (2)

J. M. Findlay, “Estimates on probability functions: a more virulent PEST,” Percept. Psychophys. 23, 181–185 (1978).
[CrossRef]

N. Graham, J. G. Robson, J. Nachmias, “Grating summation in fovea and periphery,” Vision Res. 18, 815–825 (1978).
[CrossRef] [PubMed]

1976 (1)

N. Graham, B. Rogowitz, “Spatial pooling properties deduced from the detectability of FM and quasi-AM gratings: a reanalysis,” Vision Res. 16, 1021–1026 (1976).
[CrossRef] [PubMed]

1975 (2)

C. F. Stromeyer, S. Klein, “Evidence against narrow-band spatial frequency channels in human vision: the detectability of frequency modulated gratings,” Vision Res. 15, 899–910 (1975).
[CrossRef] [PubMed]

G. B. Henning, B. G. Hertz, D. E. Broadbent, “Some experiments bearing on the hypothesis that the visual system analyses spatial patterns in independent bands of spatial frequency,” Vision Res. 15, 887–897 (1975).
[CrossRef] [PubMed]

1973 (2)

G. J. Burton, “Evidence for non-linear response processes in the human visual system from measurements on the thresholds of spatial beat frequencies,” Vision Res. 13, 1211–1225 (1973).
[CrossRef] [PubMed]

I. Bodis-Wollner, S. P. Diamond, A. Orlofsky, J. Levinson, “Detection of spatial changes of the contrast of a grating pattern,” J. Opt. Soc. Am. 63, 1296 (1973).

1971 (1)

1969 (1)

C. Blakemore, F. W. Campbell, “On the existence of neurones in the human visual system sensitive to the orientation and size of retinal images,” J. Physiol. 203, 237–260 (1969).
[PubMed]

1968 (2)

D. H. Hubel, T. N. Wiesel, “Receptive fields and functional architecture of monkey striate cortex,” J. Physiol. (London) 195, 215–243 (1968).

F. W. Campbell, J. G. Robson, “Application of Fourier analysis to the visibility of gratings,” J. Physiol. (London) 197, 551–566 (1968).

1966 (3)

J. G. Robson, “Spatial and temporal contrast sensitivity functions of the visual system,” J. Opt. Soc. Am. 56, 1141–1142 (1966).
[CrossRef]

C. Enroth-Cugell, J. G. Robson, “The contrast sensitivity of retinal ganglion cells of the cat,” J. Physiol. (London) 187, 517–552 (1966).

T. N. Wiesel, D. H. Hubel, “Spatial and chromatic interactions in the lateral geniculate body of the rhesus monkey,” J. Neurophysiol. 29, 1115–1156 (1966).
[PubMed]

1963 (1)

D. H. Hubel, T. N. Wiesel, “Shape and arrangement of columns in cat’s striate cortex,” J. Physiol. (London) 165, 559–568 (1963).

1962 (1)

D. H. Hubel, T. N. Wiesel, “Receptive fields, binocular interactions, and functional architecture in cat’s visual cortex,” J. Physiol. (London) 160, 106–154 (1962).

1958 (1)

H. B. Barlow, “Temporal and spatial summation in human vision at different background intensities,” J. Physiol. (London) 141, 337–350 (1958).

Akutsu, H.

H. Akutsu, G. E. Legge, “Discrimination of compound gratings: spatial frequency channels or local features?,” Vision Res. 35, 2685–2695 (1995).
[CrossRef] [PubMed]

Albrecht, D. G.

D. G. Albrecht, R. L. DeValois, “Striate cortex responses to periodic patterns with and without the fundamental harmonics,” J. Physiol. (London) 319, 497–514 (1981).

Anderson, S. J.

I. E. Holliday, S. J. Anderson, “Different processes underlie the detection of second-order motion at low and high temporal frequencies,” Proc. R. Soc. London Ser. B 257, 165–173 (1994).
[CrossRef]

Badcock, D. R.

S. J. Cropper, K. T. Mullen, D. R. Badcock, “Motion coherence across cardinal axes,” Vision Res. 36, 2475–2488 (1996).
[CrossRef] [PubMed]

S. J. Cropper, D. R. Badcock, “Perceived direction of motion: it takes all orientations,” Perception 24, 106 (1995).

S. J. Cropper, D. R. Badcock, A. Hayes, “On the role of second-order signals in the perceived direction of motion of type II plaid patterns,” Vision Res. 34, 2609–2612 (1994).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, G. B. Henning, “Discriminating the direction of second-order motion at short stimulus durations,” Vision Res. 33, 1785–1794 (1993).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacements of spatial beats: no role for distortion products,” Vision Res. 29, 731–739 (1989).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacements of spatial beats: a monocular capability,” Vision Res. 27, 793–797 (1987).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, “Detection of spatial beats: non-linearity or contrast increment detection?” Vision Res. 26, 343–348 (1986).
[CrossRef] [PubMed]

D. R. Badcock, C. M. Schor, “Depth-increment detection function for individual spatial channels,” J. Opt. Soc. Am. A 2, 1211–1216 (1985).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacement of periodic patterns,” Vision Res. 25, 1253–1258 (1985).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, “Separate detectors for simple and complex grating patterns?” Vision Res. 25, 1869–1878 (1985).
[CrossRef] [PubMed]

Baker, C. L.

C. L. Baker, J. C. Boulton, K. T. Mullen, “A nonlinear chromatic motion mechanism,” Vision Res. 38, 291–302 (1998).
[CrossRef] [PubMed]

J. C. Boulton, C. L. Baker, “Different parameters control motion perception above and below a critical density,” Vision Res. 33, 1803–1811 (1993).
[CrossRef] [PubMed]

J. C. Boulton, C. L. Baker, “Dependence on stimulus onset asynchrony in apparent motion: evidence for two mechanisms,” Vision Res. 33, 2013–2019 (1993).
[CrossRef] [PubMed]

Baker, C. L. J.

Y. X. Zhou, C. L. J. Baker, “A processing stream in mammalian visual cortex for non-Fourier responses,” Science 261, 98–101 (1993).
[CrossRef] [PubMed]

Barlow, H. B.

H. B. Barlow, “Temporal and spatial summation in human vision at different background intensities,” J. Physiol. (London) 141, 337–350 (1958).

Bedell, H. E.

Y. Chen, H. E. Bedell, L. J. Frishman, “Temporal-contrast discrimination and its neural correlates,” Perception 25, 505–522 (1996).
[CrossRef] [PubMed]

Benton, C. P.

C. P. Benton, A. Johnston, P. W. McOwan, “Perception of motion direction in luminance- and contrast-defined reversed-phi motion sequences,” Vision Res. 37, 2381–2399 (1997).
[CrossRef] [PubMed]

Blakemore, C.

C. Blakemore, F. W. Campbell, “On the existence of neurones in the human visual system sensitive to the orientation and size of retinal images,” J. Physiol. 203, 237–260 (1969).
[PubMed]

Bodis-Wollner, I.

I. Bodis-Wollner, S. P. Diamond, A. Orlofsky, J. Levinson, “Detection of spatial changes of the contrast of a grating pattern,” J. Opt. Soc. Am. 63, 1296 (1973).

Boulton, J. C.

C. L. Baker, J. C. Boulton, K. T. Mullen, “A nonlinear chromatic motion mechanism,” Vision Res. 38, 291–302 (1998).
[CrossRef] [PubMed]

J. C. Boulton, C. L. Baker, “Dependence on stimulus onset asynchrony in apparent motion: evidence for two mechanisms,” Vision Res. 33, 2013–2019 (1993).
[CrossRef] [PubMed]

J. C. Boulton, C. L. Baker, “Different parameters control motion perception above and below a critical density,” Vision Res. 33, 1803–1811 (1993).
[CrossRef] [PubMed]

K. T. Mullen, J. C. Boulton, “Absence of smooth motion perception in color vision,” Vision Res. 32, 483–488 (1992).
[CrossRef] [PubMed]

Bowen, R. W.

V. C. Smith, R. W. Bowen, J. Pokorny, “Threshold temporal integration of chromatic stimuli,” Vision Res. 24, 653–660 (1984).
[CrossRef] [PubMed]

Boynton, R. L.

R. L. Boynton, N. Kambe, “Chromatic difference steps of moderate size measured along theoretically critical axes,” Color Res. Appl. 5, 13–23 (1980).
[CrossRef]

Broadbent, D. E.

G. B. Henning, B. G. Hertz, D. E. Broadbent, “Some experiments bearing on the hypothesis that the visual system analyses spatial patterns in independent bands of spatial frequency,” Vision Res. 15, 887–897 (1975).
[CrossRef] [PubMed]

Burr, D. C.

Burton, G. J.

G. J. Burton, “Evidence for non-linear response processes in the human visual system from measurements on the thresholds of spatial beat frequencies,” Vision Res. 13, 1211–1225 (1973).
[CrossRef] [PubMed]

Campagne, J. C.

J. H. T. Jamar, J. C. Campagne, J. J. Koenderink, “Detectability of amplitude- and frequency-modulation of suprathreshold sine-wave gratings,” Vision Res. 22, 407–416 (1982).
[CrossRef] [PubMed]

Campbell, F. W.

C. Blakemore, F. W. Campbell, “On the existence of neurones in the human visual system sensitive to the orientation and size of retinal images,” J. Physiol. 203, 237–260 (1969).
[PubMed]

F. W. Campbell, J. G. Robson, “Application of Fourier analysis to the visibility of gratings,” J. Physiol. (London) 197, 551–566 (1968).

Cavanagh, P.

Chaparro, A.

C. F. I. Stromeyer, A. Chaparro, A. Tolias, R. E. Kronauer, “Equiluminant settings change markedly with temporal frequency,” Invest. Ophthalmol. Visual Sci. 36, 962 (1995).

A. Chaparro, C. F. Stromeyer, R. E. Kronauer, R. T. Eskew, “Separable red–green and luminance detectors for small flashes,” Vision Res. 34, 753–761 (1994).
[CrossRef]

A. Chaparro, C. F. Stromeyer, E. P. Huang, R. E. Kronauer, R. T. J. Eskew, “Colour is what the eye sees best,” Nature 361, 348–350 (1993).
[CrossRef] [PubMed]

Chen, Y.

Y. Chen, H. E. Bedell, L. J. Frishman, “Temporal-contrast discrimination and its neural correlates,” Perception 25, 505–522 (1996).
[CrossRef] [PubMed]

Chubb, C.

C. Chubb, G. Sperling, “Two motion perception mechanisms revealed through distance-driven reversal of apparent motion,” Proc. Natl. Acad. Sci. USA 86, 2985–2989 (1989).
[CrossRef] [PubMed]

C. Chubb, G. Sperling, “Drift-balanced random stimuli: a general basis for studying non-Fourier motion perception,” J. Opt. Soc. Am. A 5, 1986–2006 (1988).
[CrossRef] [PubMed]

Cropper, S. J.

S. J. Cropper, S. T. Hammett, “Adaptation to motion of a second order pattern: the motion aftereffect is not a general result,” Vision Res. 37, 2247–2259 (1997).
[CrossRef] [PubMed]

S. J. Cropper, S. T. Hammett, “Adaptation to motion of a second order pattern: the motion aftereffect is not a general result,” Vision Res. 37, 2247–2259 (1997).
[CrossRef] [PubMed]

S. J. Cropper, A. M. Derrington, “Detection and motion detection in chromatic and luminance beats,” J. Opt. Soc. Am. A 13, 401–407 (1996).
[CrossRef]

S. J. Cropper, K. T. Mullen, D. R. Badcock, “Motion coherence across cardinal axes,” Vision Res. 36, 2475–2488 (1996).
[CrossRef] [PubMed]

S. J. Cropper, D. R. Badcock, “Perceived direction of motion: it takes all orientations,” Perception 24, 106 (1995).

S. J. Cropper, A. M. Derrington, “Motion of chromatic stimuli: first-order or second-order?” Vision Res. 34, 49–58 (1994).
[CrossRef] [PubMed]

S. J. Cropper, D. R. Badcock, A. Hayes, “On the role of second-order signals in the perceived direction of motion of type II plaid patterns,” Vision Res. 34, 2609–2612 (1994).
[CrossRef] [PubMed]

S. J. Cropper, “Velocity discrimination in chromatic gratings and beats,” Vision Res. 34, 41–48 (1994).
[CrossRef] [PubMed]

Daugman, J. G.

Derrington, A. M.

S. J. Cropper, A. M. Derrington, “Detection and motion detection in chromatic and luminance beats,” J. Opt. Soc. Am. A 13, 401–407 (1996).
[CrossRef]

S. J. Cropper, A. M. Derrington, “Motion of chromatic stimuli: first-order or second-order?” Vision Res. 34, 49–58 (1994).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, G. B. Henning, “Discriminating the direction of second-order motion at short stimulus durations,” Vision Res. 33, 1785–1794 (1993).
[CrossRef] [PubMed]

A. M. Derrington, G. B. Henning, “Some observations on the masking effects of two-dimensional stimuli,” Vision Res. 29, 241–246 (1989).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacements of spatial beats: no role for distortion products,” Vision Res. 29, 731–739 (1989).
[CrossRef] [PubMed]

A. M. Derrington, “Distortion products in geniculate x-cells: a physiological basis for masking by spatially modulated gratings?” Vision Res. 27, 1377–1386 (1987).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacements of spatial beats: a monocular capability,” Vision Res. 27, 793–797 (1987).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, “Detection of spatial beats: non-linearity or contrast increment detection?” Vision Res. 26, 343–348 (1986).
[CrossRef] [PubMed]

D. R. Badcock, A. M. Derrington, “Detecting the displacement of periodic patterns,” Vision Res. 25, 1253–1258 (1985).
[CrossRef] [PubMed]

A. M. Derrington, D. R. Badcock, “Separate detectors for simple and complex grating patterns?” Vision Res. 25, 1869–1878 (1985).
[CrossRef] [PubMed]

A. M. Derrington, J. Krauskopf, P. Lennie, “Chromatic mechanisms in lateral geniculate nucleus of macaque,” J. Physiol. (London) 357, 241–265 (1984).

A. M. Derrington, “Mechanisms for coding luminance patterns: are they really linear?” in Vision: Coding and Efficiency, C. Blakemore, ed. (Cambridge, U. Press, Cambridge, UK, 1990).

DeValois, R. L.

D. G. Albrecht, R. L. DeValois, “Striate cortex responses to periodic patterns with and without the fundamental harmonics,” J. Physiol. (London) 319, 497–514 (1981).

Diamond, S. P.

I. Bodis-Wollner, S. P. Diamond, A. Orlofsky, J. Levinson, “Detection of spatial changes of the contrast of a grating pattern,” J. Opt. Soc. Am. 63, 1296 (1973).

Dowling, C. J.

Edelman, G. M.

E. D. Lumer, G. M. Edelman, G. Tononi, “Neural dynamics in a model of the thalamocortical system. II. The role of neural synchrony tested through perturbations of spike timing,” Cereb. Cortex 7, 228–236 (1997).
[CrossRef] [PubMed]

E. D. Lumer, G. M. Edelman, G. Tononi, “Neural dynamics in a model of the thalamocortical system. I. Layers, loops and the emergence of fast synchronous rhythms,” Cereb. Cortex 7, 207–227 (1997).
[CrossRef] [PubMed]

J. Wray, G. M. Edelman, “A model of color vision based on cortical reentry,” Cereb. Cortex 6, 701–716 (1996).
[CrossRef] [PubMed]

Enroth-Cugell, C.

C. Enroth-Cugell, J. G. Robson, “The contrast sensitivity of retinal ganglion cells of the cat,” J. Physiol. (London) 187, 517–552 (1966).

Eskew, R. T.

A. Chaparro, C. F. Stromeyer, R. E. Kronauer, R. T. Eskew, “Separable red–green and luminance detectors for small flashes,” Vision Res. 34, 753–761 (1994).
[CrossRef]

Eskew, R. T. J.

A. Chaparro, C. F. Stromeyer, E. P. Huang, R. E. Kronauer, R. T. J. Eskew, “Colour is what the eye sees best,” Nature 361, 348–350 (1993).
[CrossRef] [PubMed]

Favreau, O. E.

Ferrera, V. P.

H. R. Wilson, V. P. Ferrera, C. Yo, “A psychophysically motivated model for two-dimensional motion perception,” Visual Neurosci. 9, 79–97 (1992).
[CrossRef]

Findlay, J. M.

J. M. Findlay, “Estimates on probability functions: a more virulent PEST,” Percept. Psychophys. 23, 181–185 (1978).
[CrossRef]

Foley, J. M.

G. E. Legge, J. M. Foley, “Contrast masking in human vision,” J. Opt. Soc. Am. 49, 1458–1471 (1980).
[CrossRef]

Frishman, L. J.

Y. Chen, H. E. Bedell, L. J. Frishman, “Temporal-contrast discrimination and its neural correlates,” Perception 25, 505–522 (1996).
[CrossRef] [PubMed]

Graham, N.

N. Graham, J. G. Robson, “Summation of very close spatial frequencies: the importance of spatial probability summation,” Vision Res. 27, 1997–2007 (1987).
[CrossRef] [PubMed]

N. Graham, J. G. Robson, J. Nachmias, “Grating summation in fovea and periphery,” Vision Res. 18, 815–825 (1978).
[CrossRef] [PubMed]

N. Graham, B. Rogowitz, “Spatial pooling properties deduced from the detectability of FM and quasi-AM gratings: a reanalysis,” Vision Res. 16, 1021–1026 (1976).
[CrossRef] [PubMed]

Hammett, S. T.

S. J. Cropper, S. T. Hammett, “Adaptation to motion of a second order pattern: the motion aftereffect is not a general result,” Vision Res. 37, 2247–2259 (1997).
[CrossRef] [PubMed]

S. J. Cropper, S. T. Hammett, “Adaptation to motion of a second order pattern: the motion aftereffect is not a general result,” Vision Res. 37, 2247–2259 (1997).
[CrossRef] [PubMed]

Harris, J. M.

H. S. Smallman, J. M. Harris, “Nonlinear visual distortion: an effective expansive nonlinearity from assymetry in ON and OFF pathways,” Invest. Ophthalmol. Visual Sci. Suppl. 37, 232 (1996).

J. M. Harris, H. S. Smallman, “Visual distortion products from an expansive non-linearity,” Perception 24, 126b (1995).

H. S. Smallman, J. M. Harris, “Spatial-frequency selectivity of contrast-modulated masking,” Perception 24, 127b (1995).

Hayes, A.

S. J. Cropper, D. R. Badcock, A. Hayes, “On the role of second-order signals in the perceived direction of motion of type II plaid patterns,” Vision Res. 34, 2609–2612 (1994).
[CrossRef] [PubMed]

Heeley, D. W.

J. Krauskopf, D. R. Williams, D. W. Heeley, “Cardinal directions of color space,” Vision Res. 22, 1123–1131 (1982).
[CrossRef] [PubMed]

Henning, G. B.

A. M. Derrington, D. R. Badcock, G. B. Henning, “Discriminating the direction of second-order motion at short stimulus durations,” Vision Res. 33, 1785–1794 (1993).
[CrossRef] [PubMed]

A. M. Derrington, G. B. Henning, “Some observations on the masking effects of two-dimensional stimuli,” Vision Res. 29, 241–246 (1989).
[CrossRef] [PubMed]

G. B. Henning, B. G. Hertz, D. E. Broadbent, “Some experiments bearing on the hypothesis that the visual system analyses spatial patterns in independent bands of spatial frequency,” Vision Res. 15, 887–897 (1975).
[CrossRef] [PubMed]

Hertz, B. G.

G. B. Henning, B. G. Hertz, D. E. Broadbent, “Some experiments bearing on the hypothesis that the visual system analyses spatial patterns in independent bands of spatial frequency,” Vision Res. 15, 887–897 (1975).
[CrossRef] [PubMed]

Hess, R. F.

R. F. Hess, J. S. Pointer, “Evidence for spatially local computations underlying discrimination of periodic patterns in fovea and periphery,” Vision Res. 27, 1343–1360 (1987).
[CrossRef] [PubMed]

Holliday, I. E.

I. E. Holliday, S. J. Anderson, “Different processes underlie the detection of second-order motion at low and high temporal frequencies,” Proc. R. Soc. London Ser. B 257, 165–173 (1994).
[CrossRef]

Huang, E. P.

A. Chaparro, C. F. Stromeyer, E. P. Huang, R. E. Kronauer, R. T. J. Eskew, “Colour is what the eye sees best,” Nature 361, 348–350 (1993).
[CrossRef] [PubMed]

Hubel, D. H.

D. H. Hubel, T. N. Wiesel, “Receptive fields and functional architecture of monkey striate cortex,” J. Physiol. (London) 195, 215–243 (1968).

T. N. Wiesel, D. H. Hubel, “Spatial and chromatic interactions in the lateral geniculate body of the rhesus monkey,” J. Neurophysiol. 29, 1115–1156 (1966).
[PubMed]

D. H. Hubel, T. N. Wiesel, “Shape and arrangement of columns in cat’s striate cortex,” J. Physiol. (London) 165, 559–568 (1963).

D. H. Hubel, T. N. Wiesel, “Receptive fields, binocular interactions, and functional architecture in cat’s visual cortex,” J. Physiol. (London) 160, 106–154 (1962).

Jamar, J. H. T.

J. H. T. Jamar, J. C. Campagne, J. J. Koenderink, “Detectability of amplitude- and frequency-modulation of suprathreshold sine-wave gratings,” Vision Res. 22, 407–416 (1982).
[CrossRef] [PubMed]

Johnston, A.

C. P. Benton, A. Johnston, P. W. McOwan, “Perception of motion direction in luminance- and contrast-defined reversed-phi motion sequences,” Vision Res. 37, 2381–2399 (1997).
[CrossRef] [PubMed]

Julesz, B.

B. Julesz, Foundations of Cyclopean Perception (U. of Chicago Press, Chicago, Ill., 1971).

Kambe, N.

R. L. Boynton, N. Kambe, “Chromatic difference steps of moderate size measured along theoretically critical axes,” Color Res. Appl. 5, 13–23 (1980).
[CrossRef]

Kelly, D. H.

D. H. Kelly, “Spatio-temporal variation of chromatic and achromatic contrast thresholds,” J. Opt. Soc. Am. 73, 742–750 (1983).
[CrossRef] [PubMed]

D. H. Kelly, “Spatial and temporal aspects of red/green opponency,” in Image Processing, Analysis, Measurement, and Quality, G. W. Hughes, P. E. Mantey, B. E. Rogowitz, eds., Proc. SPIE901, 230–240 (1988).
[CrossRef]

Kim, J.

H. R. Wilson, J. Kim, “Perceived motion in the vector-sum direction,” Vision Res. 34, 1835–1842 (1994).
[CrossRef] [PubMed]

Klein, S.

C. F. Stromeyer, S. Klein, “Evidence against narrow-band spatial frequency channels in human vision: the detectability of frequency modulated gratings,” Vision Res. 15, 899–910 (1975).
[CrossRef] [PubMed]

Koenderink, J. J.

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Other (10)

B. Julesz, Foundations of Cyclopean Perception (U. of Chicago Press, Chicago, Ill., 1971).

For the purposes of argument I shall assume that these authors do also assign some useful role for the distortion product as well as the detrimental effect its presence has on detection of a first-order modulation. Their work is certainly cited by other authors, particularly those interested in second-order motion detection, as evidence for a nonlinearity capable of coding the contrast modulation. Whether or not this is the case does not affect the substance of the arguments or the data contained in this paper.

The terminology used in this paper will refer to an amplitude-modulated grating [Eq. (5)] specifically as an AM grating and use the term contrast modulation to describe generally the variation in the contrast envelope of a given stimulus.

It is worth noting that observers are unable to discriminate between a static beat and a static AM grating of 100% modulation depth, which indicates that, for this task at least, the spatial-phase profile is unavailable or unused.

A. B. Watson, “Temporal sensitivity,” in Handbook of Perception and Human Performance, K. R. Boff, ed. (Wiley, New York, 1986).

Henning et al. (Ref. 6, p. 893) calculated that their mask did not produce a detectable increment in the contrast of their proposed distortion product that would explain their data. The explanation offered here is slightly different in that the local mean luminance change induced on the carrier by the mask will add noise directly into the local contrast estimate by changing the mean luminance. The suggestion is that this envelope noise will make it harder to discriminate an AM envelope from a QFM envelope—the task at hand.

A. M. Derrington, “Mechanisms for coding luminance patterns: are they really linear?” in Vision: Coding and Efficiency, C. Blakemore, ed. (Cambridge, U. Press, Cambridge, UK, 1990).

One anonymous referee suggested a better paradigm would be to perform a spatial 2AFC contrast-increment task with two grating regions of approximately a quarter of an envelope period in width and separated by the same amount of uniform field at the mean luminance. I agree with the referee but do not feel the results would be cause me to change my overall conclusions.

The same referee also suggested that there may be a significant internal contrast modulation introduced into a QFM grating by the change in sensitivity of a given channel as a function of spatial frequency. This is true but is also dependent on the depth (extent) of frequency modulation (0.2 cpd in this case) relative to the width of the channel (conservatively, an octave half-width54). I do not feel that this effect is significant with the current stimuli, considering both the shallow frequency modulation and the suprathreshold carrier contrast: principally, the QFM grating remains a discontinuity cue. The referee’s comment, however, is a pertinent point and should be borne in mind.

D. H. Kelly, “Spatial and temporal aspects of red/green opponency,” in Image Processing, Analysis, Measurement, and Quality, G. W. Hughes, P. E. Mantey, B. E. Rogowitz, eds., Proc. SPIE901, 230–240 (1988).
[CrossRef]

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Figures (6)

Fig. 1
Fig. 1

Effect of the detection paradigm on the ability to discriminate an amplitude modulation of 1 cpd in a 10-cpd luminance carrier grating. (a) The minimum detectable percent modulation depth plotted against the duration of presentation for observers SJC and TM. Each point is the result of four threshold estimates; error bars are ±SEM throughout. The key indicates the carrier contrast in log units above carrier-detection threshold and the “r” suffix indicates that the contrast of the nonsignal interval was randomized. Raised (shaded square) data points indicate that the task was impossible. See Section 3 (Experiment 1) for further details. (b) Summary of (a) at a single duration of 0.5 s. Minimum detectable modulation depth is plotted against carrier contrast in log units above detection threshold.

Fig. 2
Fig. 2

Effect of carrier and envelope spatial frequency on the ability to discriminate the amplitude modulation for observer SJC. Modulation depth is plotted against the carrier contrast in multiples of detection threshold. All carriers are achromatic; duration is 0.25 s.

Fig. 3
Fig. 3

Effect of carrier contrast on amplitude-modulation detection in RG and BY equiluminant chromatic and achromatic carriers (1-cpd carrier, 0.2-cpd amplitude modulation) at 0.25 s duration for observers SJC and DM.

Fig. 4
Fig. 4

(a) Effect of stimulus duration on the ability to discriminate amplitude modulation. Percent modulation is plotted against the duration (half-width of the raised-cosine temporal envelope) for observer SJC, with 5-cpd luminance carrier and 1-cpd amplitude modulation. Carrier contrast is indicated in the key in log units above carrier-detection threshold. (b) As (a) except that the pattern is a 1-cpd achromatic carrier with an amplitude modulation of 0.2 cpd for observers SJC and DM. (c) As (a) but with an RG carrier grating and for observers SJC and DM. (d) As (a) but with a BY carrier grating and for observers SJC and DM.

Fig. 5
Fig. 5

(a) Comparison of amplitude-modulation detection, AM/QFM discrimination, and contrast-increment detection as a function of stimulus duration. All stimuli are 1-cpd carriers with a 0.2-cpd modulation (QFM or AM) or just the carrier alone for contrast-increment detection. Two carrier contrasts are shown, threshold+0.3 (open symbols) and threshold+0.7 (filled symbols) log unit for observers SJC and DM. The particular task is indicated in the key. See Subsection 2.D. (b) As (a) except that the carrier is either an RG (observer DM) or a BY (observer SJC) grating. (c) Summary of the effect of carrier contrast on the ability to discriminate AM and QFM luminance gratings (Subsection 2.D). Filled symbols indicate the presence of a 0.2-cpd masking grating (see Subsection 2.E); duration is 0.25 s.

Fig. 6
Fig. 6

(a) Detection of a 0.2-cpd luminance or chromatic (RG) grating in the presence and absence of an AM-grating mask (0.2:1 cpd). Mean L–M-cone contrast is plotted against the duration of presentation. The standard unmasked conditions are shown by the filled circle (luminance) and filled diamond (RG) for a duration of 0.25 s: This is the basic contrast-detection threshold for a 0.2-cpd luminance or color grating. Open circles show the effect of a 1-cpd luminance grating at a contrast of 0.7 log unit above detection threshold on the detectability of the 0.2-cpd luminance grating for all durations. Open diamonds show the effect of a 1-cpd RG chromatic grating mask on the detection of a 0.2-cpd RG grating. For the purposes of this work, this second condition is essentially the unmasked condition because the simple detection of a 0.2-cpd grating (filled circle) against a blank field has very different temporal properties than when the 1-cpd carrier is present in both signal and nonsignal intervals. See Subsection 2.E. (b) Detection of a 0.2-cpd luminance or chromatic grating in the presence of an AM-grating mask as a function of different relative phases of test and mask. Symbols are as in (a); duration is 0.25 s. Different stimulus configurations are explained in Subsection 2.E.

Equations (7)

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L(y)=Lm{1+C sin[2π(fy+ϕ)]},
L(y)=Lm{1+C1 sin[2πy(f1)]+C2 sin[2πy(f2)]}.
sin A+sin B=2 cos[(A-B)/2]sin[(A+B)/2].
L(y)=Lm(1+2C cos{2πy[(f1-f2)/2]}×sin{2πy[(f1+f2)/2]}).
L(y)=Lm{1+C1 sin[2πy(f1+ϕ1)]+C2 sin[2πy(f2+ϕ2)]+C3 sin[2πy(f3+ϕ3)]},
L(y)=Lm{1+C2 sin[2πy(f2)]×[1+M cos 2πy(fenv)]},
L(y)=Lm(1+C2 cos{2πy(f2)+tan-1[M cos 2πy(fenv)]}×[1+M2 cos2 2πy(fenv)]1/2).

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