Psychophysical determination of the spatial connectivity function in a model of contour salience

Recently, we proposed a cortical-based model that accounts for a range of psychophysical results on contour salience [S.C. Yen, L.H. Finkel, Vision Res. 38 (1998) 719}741]. In this model, cortical units are interconnected by long-range horizontal connections where the connection strength between units is de"ned by an inter-element spatial connectivity function. In the present work, we determine the spatial connectivity function psychophysically and compare the result to the function implemented in the original computational model. The results suggest the original product of gaussian spatial weighting function does not completely describe the psychophysical data. Rather, we "nd that the connectivity function is `tapereda suggesting a lack of separability between position and orientation in cortical connectivity. ( 1999 Elsevier Science B.V. All rights reserved.