Effect of instructions on the disappearance of steadily fixated luminous figures

A controversy has existed in the literature between peripheral and central processes as explanations for the disappearances found in steadily fixated luminous figures. The present experiment (N = 24 male and female undergraduates) was designed to test the extent to which the instructions or experimenter bias influence the disappearances of three different luminous figures. The results indicated that the type of instruction did affect the frequency of disappearances, but not the kind of disappearances. A significant difference was also found in the frequency of disappearances among the different figures. These results support the central process hypothesis.