New configurational effects on perceived contrast and brightness: second-order White's effects

Novel phenomena of perceived contrast and brightness in spatial configurations are presented, which are of the type used by White but consist exclusively of contrast variations or of combined contrast and luminance variations. As with White's effect, perceived contrast and brightness in these displays do not correspond to predictions based on low-level mechanisms of contrast and brightness induction, and it is suggested that spatial organisation influences the appearance of first-order and second-order stimuli in a similar fashion.