Lateral interactions between spatial filters were explored with a lateral masking paradigm.
Contrast sensitivity (two-alternative forced-choice) for a Gabor signal in the presence of two
flanking high contrast Gabor signals (masks) was measured. When the target to mask
distance was less than 2 target wavelengths the contrast sensitivity decreased up to a factor
of two relative to a no mask condition. At larger separations, up to eight wavelengths, an
increase in contrast sensitivity occurred. This increase was maximal at separation distances …

In order to examine lateral interactions between spatial filters, the authors determined
contrast detection thresholds for Gabor patches flanked by two high contrast Gabors. The
orientation of each patch (local orientation) and that of a virtual line connecting the two
peripheral masks (global orientation) were both varied. At small target-mask separations,
contrast sensitivity was reduced. At large separations, contrast sensitivity was facilitated, with
most enhancement occuring for collinear stimulus arrangements, where there is no offset …