title: Differences in the magnitude of the Delboeuf Illusion and Usnadze Effect during adulthood.
abstract: The Delboeuf illusion (Type I) and Usnadze Effect (Type II) were used to investigate changes in perceptual processes in 72 female subjects, aged 20-79 years. Unlike other studies, small figures (less than 2 degrees) were presented for brief periods under fixation conditions. The magnitude of the Delboeuf illusion increased in old age, while the magnitude of the Usnadze Effect showed no change.
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging; D005260:Female; D006801:Humans; D007088:Illusions; D008875:Middle Aged; D014796:Visual Perception