EFFECTS OF FORM IN KOFFKA-RING TYPE PATTERNS .1. COMPARISON BETWEEN HUE AND BRIGHTNESS CONTRASTS

The purpose of this study is to examine the effects of figural unity o i non-annular test figure (TF) an simultaneous hue and brightness cont rasts in Koffka-ring type patterns. To manipulate the TF's unity syste matically, we investigated two stimulus conditions (five degrees of se paration and two styles of division) of the TF. Eight subjects measure d, through matching, the apparent hue and brightness of the TF overlap ping red-green or black-white inducing figures. The results revealed t hat the magnitudes of hue and brightness contrasts (MHCs and MBCs) in divided and undivided TFs decreased as the degree of separation decrea sed. However, both MHCs and MBCs in the undivided TFs decreased more s teeply than those in the divided TFs. In conclusion, the MHCs and the MBCs were significantly influenced by the separation and the division of the TF in almost the same manner, and the effects of dividing line on perceiving the figural unity were discussed.