PERCEPTUAL ORGANIZATION EVOKES SIMULTANEOUS LIGHTNESS CONTRAST

Principles of perceptual organization can cause simultaneous lightness contrast to be seen in patterns in which the inducing regions are not proximal to the target. In three experiments a match was made between two grey targets, one of which belonged to a white perceptual groupin g and the other to a black one. In experiment 1, perceived belongingne ss was a product of common fate and figural alignment (columns of blac k dots and columns of white dots moved up and down in counterphase). I n experiment 2, belongingness was evoked with only figural alignment. In experiment 3, belongingness was induced by common fate alone. In al l three experiments it was found that the grey target belonging to the white group appeared darker than the grey target belonging to the bla ck group.