RTs of the first group (age, 20–30 years) were measured on two different days (interval: 12–153 days). In the ANCOVA model, the factors luminance (of the target presented), eccentricity in the visual field, side of the visual field (nasal, midline, temporal), half (upper part, midline, lower part), code, examination, examination * code (* denotes interaction of two factors), nop, nop2, nop * code, and nop2 * code were analyzed. Only stimuli that started from the horizontal or vertical midline were classified as midline. Examination had two possible values: first or second visit. In our model, each subject exhibited a systematic deviation from the general difference between visits (i.e., the examination * code interaction). The parabola over nop, too, was estimated for each subject and as a general trend.