Muto Hiroyuki, Ide Mayu, Tomita Akitoshi, Morikawa Kazunori
School of Human Sciences, Osaka University, Suita, Japan.
Front Psychol. 2019 Jul 5;10:1510. doi: 10.3389/fpsyg.2019.01510. eCollection 2019.
Previous research found that application of eyeshadow on the upper eyelids induces overestimation of eye size. The present study examined whether or not this eyeshadow illusion is dependent on viewpoint. We created a three-dimensional model of a female face and manipulated the presence/absence of eyeshadow and face orientation around the axis of yaw (Experiment 1) or pitch (Experiment 2) rotation. Using the staircase method, we measured perceived eye size for each face stimulus. Results showed that the eyeshadow illusion occurred regardless of face orientation around axes of both yaw and pitch rotations. Crucially, the illusion's magnitude did not vary across face orientations; lack of interaction between the illusion's magnitude and face orientation was confirmed by small values of Bayes factors. These findings ruled out the hypothesis that eyeshadow serves as a depth cue and leads to overestimation of eye size due to size-distance scaling. Alternatively, the present findings suggest that the eyeshadow illusion can be well explained by the assimilation between the eyes and eyeshadow, which also facilitates assimilation between the eyes and eyebrows. Practical implications and the present findings' generalizability are also discussed.
先前的研究发现，在上眼睑涂抹眼影会导致对眼睛大小的高估。本研究考察了这种眼影错觉是否依赖于观察角度。我们创建了一个女性面部的三维模型，并围绕偏航轴（实验1）或俯仰轴（实验2）旋转来操控眼影的有无以及面部朝向。使用阶梯法，我们测量了每个面部刺激下的感知眼睛大小。结果表明，无论面部围绕偏航轴和俯仰轴如何旋转，眼影错觉都会出现。至关重要的是，错觉的程度在不同面部朝向之间并没有变化；贝叶斯因子的小数值证实了错觉程度与面部朝向之间缺乏交互作用。这些发现排除了眼影作为深度线索并由于大小 - 距离缩放导致眼睛大小高估的假设。另外，目前的研究结果表明，眼影错觉可以通过眼睛与眼影之间的同化很好地解释，这也促进了眼睛与眉毛之间的同化。还讨论了实际应用以及本研究结果的普遍性。
