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Responses of neurons in cat striate cortex to vernier offsets in reverse contrast stimuli

  • N.v. Swindale (a1)

This paper examines how the responses of cells in area 17 of the cat vary as a function of the vernier offset between a bright and a dark bar. The study was prompted by the finding that human vernier acuity is reduced for bars or edges of opposite contrast sign (Mather & Morgan, 1986; O'Shea & Mitchell, 1990). Both simple and complex cells showed V-shaped tuning curves for reverse contrast stimuli: i.e. response was minimum at alignment, and increased with increasing vernier offset. For vernier bars with the same contrast sign, γ-shaped tuning curves were found, as reported earlier (Swindale & Cynader, 1986). Sensitivity to offset was inversely correlated in the two paradigms. However, complex cells with high sensitivity to offsets in a normal vernier stimulus were significantly less sensitive to offsets in reverse contrast stimuli. A cell's response to a vernier stimulus in which both bars are bright can be predicted by the shape of its orientation tuning curve, if the vernier stimulus is approximated by a single bar with an orientation equal to that of a line joining the midpoints of the two component bars (Swindale & Cynader, 1986). This approximation did not hold for the reverse contrast condition: orientation tuning curves for compound barswere broad and shallow, rather than bimodal, with peaks up to 40 deg from the preferred orientation. Results from simple cells were compared with predictions made by a linear model of the receptive field. The model predicted the V-shaped tuning curves found for reverse contrast stimuli. It also predicted that absolute values of tuning slopes for vernier offsets in reverse contrast stimuli might sometimes be higher than with normal stimuli. This was observed in some simple cells. The model was unable to explain the shape of orientation tuning curves for compound bars, nor could it explain the breakdown of the equivalent orientation approximation.

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Adelsen, E.H. & Bergen, J.R. (1985). Spatiotemporal energy models for the perception of motion. Journal of the Optical Society of America A 2, 284299.
Baker, C.L. Jr & Cynader, M.S. (1986). Spatial receptive field properties of direction selective neurons in cat striate cortex. Journal of Neurophysiology 6, 11361152.
Cavanagh, P., Brussell, E.M. & Stober, S.R. (1981). Evidence against independent processing of black and white features. Perception and Psychophysics 29, 423428.
Fendick, M. & Swindale, N.V. (1994). Vernier acuity for edges defined by flicker. Vision Research 34, 27172726.
Hall, S. (1992). The effect of stimulus contrast and temporal offset motion on vernier acuity in the cat and human. Unpublished M.Sc. Thesis, Dalhousie University.
Hammond, P. & MacKay, D.M. (1977). Differential responsiveness of simple and complex cells in cat striate cortex to visual texture. Experimental Brain Research 30, 275296.
Jones, J.P. & Palmer, L.A. (1987). The two-dimensional spatial structure of simple receptive fields in cat striate cortex. Journal of Neurophysiology 58, 11871211.
Kulikowski, J.J., Marcelja, 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, 187198.
Levi, D.M. & Westheimer, G. (1987). Spatial-interval discrimination in the human fovea: What delimits the interval? Journal of the Optical Society of America A 4, 13041313.
Mather, G. & Morgan, M. (1986). Irradiation: Implications for theories of edge localization. Vision Research 26, 10071015.
Movshon, J.A., Thompson, I.D. & Tolhurst, D.J. (1978). Receptive-field organization of complex cells in the cat's striate cortex. Journal of Physiology (London) 283, 7999.
Murphy, K.M., Jones, D.G. & Van Sluyters, R.C. (1988). Vernier acuity for an opposite contrast stimulus. Investigative Ophthalmology and Visual Science (Suppl.) 29, 138.
Murphy, K.M. & Mitchell, D.E. (1991). Vernier acuity of normal and visually deprived cats. Vision Research 31, 253266.
O'Shea, R.P. & Mitchell, D.E. (1990). Vernier acuity with opposite-contrast stimuli. Perception 19, 207221.
Skottun, B.C., Grosof, D.H. & DeValois, R.L. (1988). Responses of simple and complex cells to random dot patterns: A quantitative comparison. Journal of Neurophysiology 59, 17191735.
Spitzer, H. & Hochstein, S. (1985). A complex-cell receptive-field model. Journal of Neurophysiology 53, 12661286.
Swindale, N.V. & Cynader, M.S. (1986). Vernier acuity of neurons in cat visual cortex. Nature 319, 591593.
Swindale, N.V. & Cynader, M.S. (1989). Vernier acuities of neurons in area 17 of cat visual cortex: Their relation to stimulus length and velocity, orientation selectivity, and receptive-field structure. Visual Neuroscience 2, 165176.
Swindale, N.V. (1993 a). Neuronal vernier acuity for opposite contrast stimuli. Investigative Ophthalmology and Visual Science (Suppl.) 34, 794.
Swindale, N.V. (1993b). Contrast integration along the length axis of area 17 neurons: Linear or non-linear? Society for Neuroscience Abstracts 19, 628.
Swindale, N.V. & Mitchell, D.E. (1994). Comparison of receptive-field properties of neurons in area 17 of normal and bilaterally amblyopic cats. Experimental Brain Research 99, 399410.
Waugh, S.J., Levi, D.M. & Carney, T. (1993). Orientation, masking, and vernier acuity for line targets. Vision Research 33, 16191638.
Westheimer, G. (1981). Visual hyperacuity. In Progress in Sensory Physiology, Vol. I, ed. Autrim, H., pp. 130. Berlin: Springer.
Wilson, H.R. (1986). Responses of spatial mechanisms can explain hyperacuity. Vision Research 26, 453469.
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Visual Neuroscience
  • ISSN: 0952-5238
  • EISSN: 1469-8714
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