@article{oai:soar-ir.repo.nii.ac.jp:00000561, author = {今井, 章}, journal = {人文科学論集. 人間情報学科編}, month = {Mar}, note = {This study examined the event-related potentials (ERPs) under the condition that four observers compared a single circle (comparison stimulus; visual angle: 1.0°) to outer circle of a concentric circle (Delboeuf illusion figure; standard stimulus) and judged the apparent size of the single circle to be large or small by a key pressing. The constant method was used, and the inner circle was prepared for five kinds of diameter, constructing 2/3 (0.67°/1.0°, 1.0°/1.5°), 2/6 (0.33°/1.0.°), 2/12 (0.17°/1.0°), and 2/18 (0.11°/1.0°) of inner/outer ratios. The ERPs were obtained at four scalp sites of Fz, Cz, Pz, and Oz. The outer circle was underestimated for all of ratio conditions except for the 2/3 (1.0°/1.5°) of which condition the outer circle was physically larger than the comparison stimulus, showing an occurrence of assimilation process. Although several components of the ERPs were emerged under the observation of Delboeuf illusion, the amplitudes of N1 at Fz and Cz, and those of P3 at Cz and Pz were proportionally changed in accordance with the psychometric function produced by the behavioral data. It is suggested that the N1 and P3 amplitudes may covary with the process of assimilation when observer investigates Delboeuf illusion. Functional significances of the N1 and P3 amplitudes are discussed along with the previous findings and the present results, Article, 人文科学論集. 人間情報学科編 46: 19-31(2012)}, pages = {19--31}, title = {事象関連電位によるデルブーフ錯視の検討(3) : 内円が縮小する条件における脳の応答について}, volume = {46}, year = {2012} }