Retinal size as a determiner of the direction of size distortion in figural after-effects

When dealing with size distortions, the direction of the distortion is determined by the retinal size of the T-figure with respect to the retinal size of the I-figure. When the T-figure is retinally smaller than the I-figure it is distorted toward appearing even smaller; when it is retinally larger than the I-figure it is distorted toward appearing even larger; and when the two are retinally equal, there is no distortion. If the T-figures are too much larger or smaller than the I-figure, the distortion ceases. The traditional distance paradox is observed where the distance is defined retinally. The apparent size of the figures is irrelevant to a prediction of what sort of distortion takes place. Sutherland's hypothesis that apparent size determines the direction of distortion when retinal sizes are equated is not supported.     

Apparent distance vs. apparent size as determiners of figural after-effects

Abstract.— Sutherland's (1954) much discussed experimental design was analysed in a new fashion. When the original experiment was repeated as such, the expected FAE was found. However, when the same IFs and TFs were presented in a vertical position, no significant FAEs were found. The results lend support to the interpretation presented earlier by Kolehmainen (1968): The FAE found by Sutherland was apparently due to an uncontrolled binocular disparity resulting in a different localization of stimulus figures in respect to the fixation point.