ABSTRACT
Brightness enhancement in the Ehrenstein illusion was measured using brightness matching and magnitude estimation. In one experiment, Ehrenstein patterns varied in number of constituent radial lines from 2 to 32. In another experiment, the size of the illusory area was varied from 9 to 34 min of visual angle. Increasing the number of lines resulted in increased brightness contrast. Over the restricted range of gap sizes investigated, the brightness effect was enhanced with increases of gap size. A receptive field model is proposed to accommodate these findings.
