The life-span trend in the magnitude of the Mueller-Lyer illusion as a function of hue and age.

Mueller-Lyer illustrations produced by hue contrast were used to investigate age differences with participants ranging in age from 20 to 79 years. As expected, there was no age difference in the magnitude of the illusion when the Mueller-Lyer figure was produced by hue contrast. A significant main effect of hue was found, with no interaction between hue and age. These findings support Pollack's nondevelopmental explanation for age effects on Type I illusions.