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Vernier acuities of neurons in area 17 of cat visual cortex: Their relation to stimulus length and velocity, orientation selectivity, and receptive-field structure

Published online by Cambridge University Press:  02 June 2009

N. V. Swindale  and
M. S. Cynader
N. V. Swindale
Affiliation:
Department of Psychology, Dalhousie University, Nova Scotia, Canada
M. S. Cynader
Affiliation:
Department of Psychology, Dalhousie University, Nova Scotia, Canada
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Abstract

The sensitivity of neurons in area 17 of the cat's visual cortex to vernier offset was expressed as the percentage reduction in response caused by the introduction of a given offset into a bar stimulus moving across the receptive field. There was a wide variation in sensitivity: in some cells response could be halved by an offset equal to a fifth of receptive-field width (defined as twice the standard deviation of a Gaussian curve fitted to the response profile), while other cells showed no sensitivity. The highest absolute sensitivities of complex and simple cells were similar, although most cells with poor sensitivity were complex.

Sensitivity was largely unaffected by changes in stimulus velocity and stimulus length, although there was a tendency for sensitivity to increase with decreasing bar length.

Comparisons of orientation tuning curves with vernier tuning curves showed that the response to a vernier stimulus approximated the response to a single bar of the same overall length and an orientation equal to that of a line joining the midpoints of each bar. This was true for a wide range of sensitivity values.

Vernier sensitivity was correlated with a measure of length summation H, which is positive when there is net facilitation between the bars, and negative when there is net inhibition. Vernier sensitivity was highest in cells with large values of H, and least in cells where H was negative.

We examined a linear model of the simple cell receptive field which, together with a variable response threshold, was able to explain the correlation between vernier acuity and length summation. Although this model accounted qualitatively for many of our findings, the majority of simple cells had tuning curves that were sharper than the predicted ones. This suggests that there are nonlinearities in the behavior of many simple cells whose effect is to increase the sharpness of orientation tuning and consequently vernier sensitivity.

Keywords

Vernier acuityHyperacuityOrientation tuningQuantitative neurophysiologyLength summation
Type
Research Articles
Information
Visual Neuroscience , Volume 2 , Issue 2 , February 1989 , pp. 165 - 176
Copyright
Copyright © Cambridge University Press 1989

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References

Andrews, D.P. (1967). Perception of contour orientation in the central fovea. Vision Research 7, 975–1013.CrossRefGoogle ScholarPubMed
Andrews, D.P., Butcher, A.K. & Buckley, B.R. (1973). Acuities for spatial arrangement of line figures: human and ideal observers compared. Vision Research 13, 599–620.CrossRefGoogle ScholarPubMed
Baker, C.L. & Cynader, M.S. (1986). Spatial receptive-field properties of direction selective neurons in cat striate cortex. Journal of Neurophysiology 55, 1136–1152.CrossRefGoogle ScholarPubMed
Barlow, H.B., Blakemore, C. & Pettigrew, J.D. (1967). The neural mechanism of binocular depth discrimination. Journal of Physiology, 193, 327–342.Google Scholar
Beaulieu, C. & Cynader, M.S. (1989). Effect of the richness of the visual environment on response properties in cat visual cortex (submitted).Google Scholar
Bradley, A., Skottun, B.C., Ohzawa, I., Sclar, G., & Freeman, R.D. (1985). Neurophysiological evaluation of the differential response model for orientation and spatial-frequency discrimination. Journal of the Optical Society of America A 2, 1607–1610.Google Scholar
Caceci, M.S. & Cacheris, W.P. (1984). Fitting curves to data. Byte 9, 340–362.Google Scholar
Campbell, F.W., Cleland, B.G., Cooper, G.F. & Enroth-Cugell, C. (1968). The angular selectivity of visual cortical cells to moving gratings. Journal of Physiology 198, 237–250.Google Scholar
Cynader, M.S. & Regan, D.M. (1978). Neurones in cat parastriate cortex sensitive to the direction of motion in three-dimensional space. Journal of Physiology 274, 549–569.CrossRefGoogle Scholar
Dean, A. (1981). The relationship between response amplitude and contrast for cat striate cortical neurons. Journal of Physiology 318, 413–427.Google Scholar
Dobbins, A., Zucker, S.W. & Cynader, M.S. (1987). End-stopped neurons in the visual cortex as a substrate for calculating curvature. Nature 329, 438–439.CrossRefGoogle Scholar
Geisler, W.S. (1984). Physical limits of acuity and hyperacuity. Journal of the Optical Society of America Series A 1, 775–782.Google Scholar
Gilbert, CD. (1977). Laminar differences in receptive field properties of cells in cat primary visual cortex. Journal of Physiology 268, 391–421.CrossRefGoogle ScholarPubMed
Hammond, P. & Ahmed, B. (1985). Length summation of complex cells in cat striate cortex: a reappraisal of the "special/standard" classification. Neuroscience 15, 639–649.CrossRefGoogle ScholarPubMed
Hammond, P. & Mackay, D.M. (1983). Influence of luminance gradient reversal on simple cells in feline striate cortex. Journal of Physiology 337, 69–87.CrossRefGoogle ScholarPubMed
Howard, I.P. (1982). Human Visual Orientation, England: Wiley, Chichester.Google Scholar
Hubel, D.H. & Wiesel, T.N. (1962). Receptive fields, binocular interaction, and functional architecture in the cat's visual cortex. Journal of Physiology 160, 106–154.CrossRefGoogle ScholarPubMed
Hubel, D.H. & Wiesel, T.N. (1965). Receptive fields and functional architecture in two nonstriate visual areas (18 and 19) of the cat. Journal of Neurophysiology 28, 229–289.CrossRefGoogle Scholar
Jones, J. & Palmer, L. (1984). Simple receptive fields in cat striate cortex: a comparison with Gabor functions in two dimensions of space and two dimensions of spatial frequency. Society for Neuroscience Abstracts 10, 237.8.Google Scholar
Koch, C., Poggio, T. & Torre, V. (1982). Retinal ganglion cells: a functional interpretation of dendritic morphology. Philosophical Transactions of the Royal Society B (London): 298, 227–264.Google Scholar
Kulikowski, J.J., Marceija, S. & Bishop, P.O. (1982). Theory of spatial position and spatial-frequency relations in receptive fields of simple cells in the visual cortex. Biological Cybernetics 43, 187–198.Google Scholar
Levi, D.M. & Klein, S. (1982). Hyperacuity and amblyopia. Nature 298, 268–270.CrossRefGoogle ScholarPubMed
Marr, D. & Hildreth, E. (1980). Theory of edge detection. Proceedings of the Royal Society B (London): 200, 269–294.Google Scholar
Movshon, J.A., Thompson, I.D. & Tolhurst, D.J. (1978). Spatial summation in the receptive fields of simple cells in the cat's striate cortex. Journal of Physiology 283, 54–77.Google ScholarPubMed
Murphy, K. & Mitchell, D.E. (1989). (Manuscript in preparation).Google Scholar
Nedler, J.A. & Mead, R. (1965). A simplex method for function minimization. Computer Journal 7, 308.Google Scholar
Ohzawa, I.Sclar, G. & Freeman, R.D. (1985). Contrast gain control in the cat's visual system. Journal of Neurophysiology 54, 651–667.Google Scholar
Schumer, R.A. & Movshon, J.A. (1984). Length summation of simple cells of cat striate cortex. Vision Research 24, 565–571.CrossRefGoogle ScholarPubMed
Sullivan, G.D., Oatley, K. & Sutherland, N.S. (1972). Vernier acuity as affected by target length and separation. Perception and Psychophysics 12, 438–444.CrossRefGoogle Scholar
Swindale, N.V. & Cynader, M.S. (1986). Vernier acuity of neurones in cat visual cortex. Nature 319, 591–593.CrossRefGoogle ScholarPubMed
Torre, V. & Poggio, T. (1978). A synaptic mechanism possibly underlying directional selectivity to motion. Proceedings of the Royal Society B (London) 202, 409–416.Google Scholar
Watt, R.J.Morgan, M.J. & Ward, R.M. (1983). The use of different cues in vernier acuity. Vision Research 23, 991–995.Google Scholar
Westheimer, G. (1981). Visual hyperacuity. In Progress in Sensory Physiology 1, ed. Autrim, H., pp. 1–30, Berlin: Springer.Google Scholar
Westheimer, G. & Mckee, S.P. (1977). Spatial configurations for visual hyperacuity. Vision Research 17, 941–947.Google Scholar
Wilson, H.R. (1985). Responses of spatial mechanisms can account for vernier acuity. Investigative Ophthalmology and Visual Science (Suppl.) 26, 82.Google Scholar