Spatial facilitation predicted with end-stopped spatial filters

We examined the role of putative end-stopped spatial filters in determining spatial facilitation associated with a line target flanked by square inducers. Results obtained in normal and amblyopic observers were well predicted by end-stopping and other receptive field features of end-stopped spatial filters revealed in a modified Westheimer paradigm. The role of target-inducer collinearity, the effects of inducer polarity, and facilitation associated with non-orientational circular targets, were also studied. Our results suggest that spatial facilitation results from antagonism surrounding spatial filter centers, with end-stopping playing a prominent role.