Food Function Division, National Food Research Institute, National Agriculture and Food Research Organization, Ibaraki, Japan.
PLoS One. 2013 Oct 25;8(10):e78621. doi: 10.1371/journal.pone.0078621. eCollection 2013.
It is known that subjective contours are perceived even when a figure involves motion. However, whether this includes the perception of rigidity or deformation of an illusory surface remains unknown. In particular, since most visual stimuli used in previous studies were generated in order to induce illusory rigid objects, the potential perception of material properties such as rigidity or elasticity in these illusory surfaces has not been examined. Here, we elucidate whether the magnitude of phase difference in oscillation influences the visual impressions of an object's elasticity (Experiment 1) and identify whether such elasticity perceptions are accompanied by the shape of the subjective contours, which can be assumed to be strongly correlated with the perception of rigidity (Experiment 2).
METHODOLOGY/PRINCIPAL FINDINGS: In Experiment 1, the phase differences in the oscillating motion of inducers were controlled to investigate whether they influenced the visual impression of an illusory object's elasticity. The results demonstrated that the impression of the elasticity of an illusory surface with subjective contours was systematically flipped with the degree of phase difference. In Experiment 2, we examined whether the subjective contours of a perceived object appeared linear or curved using multi-dimensional scaling analysis. The results indicated that the contours of a moving illusory object were perceived as more curved than linear in all phase-difference conditions.
CONCLUSIONS/SIGNIFICANCE: These findings suggest that the phase difference in an object's motion is a significant factor in the material perception of motion-related elasticity.
已知当图形涉及运动时，即使会出现主观轮廓，也能感知到它们。然而，目前尚不清楚这是否包括对虚幻表面的刚性或变形的感知。特别是，由于之前的研究中使用的大多数视觉刺激都是为了产生幻象的刚性物体而生成的，因此这些幻象表面的材料特性（如刚性或弹性）的潜在感知尚未得到检验。在这里，我们阐明了振荡的相位差幅度是否会影响对物体弹性的视觉印象（实验 1），并确定了这种弹性感知是否伴随着主观轮廓的形状，而主观轮廓可以假定与刚性的感知密切相关（实验 2）。
方法/主要发现：在实验 1 中，控制了诱导器的振荡运动中的相位差，以研究它们是否会影响对幻象物体弹性的视觉印象。结果表明，幻象表面的弹性印象随着相位差的程度而系统地翻转。在实验 2 中，我们使用多维标度分析来检查感知物体的主观轮廓是否呈线性或曲线。结果表明，在所有相位差条件下，移动幻象物体的轮廓被感知为更弯曲而不是线性。
结论/意义：这些发现表明，物体运动中的相位差是与运动相关的弹性的材料感知的重要因素。
