RT Journal Article
A1 Qian, Kun
A1 Mitsudo, Hiroyuki
T1 Eggs illusion: Local shape deformation generated by a grid pattern
JF Journal of Vision
JO Journal of Vision
YR 2016
DO 10.1167/16.15.27
VO 16
IS 15
SP 27
OP 27
SN 1534-7362
AB  In this study, we report a new visual shape illusion, the eggs illusion, in which circular disks located at the midpoints between adjacent grid intersections are perceived as being deformed to ellipses. In Experiment 1, we examined the eggs illusion by using a matching method and found that grid luminance and patch size play a critical role in producing the illusory deformation. In Experiment 2, we employed several types of elliptic or circular patches to examine the conditions in which the illusory deformation was cancelled or weakened. We observed that the illusory deformation was dependent on local grid orientation. Based on these results, we found several common features between the eggs illusion and the scintillating grid illusion. This resemblance suggests a possibility that similar mechanisms underlie the two phenomena. In addition to the scintillating grid illusion, we also considered several known perceptual phenomena that might be related to the eggs illusion, i.e., the apparent size illusion, the shape-contrast effect, and the Orbison illusion. Finally, we discuss the role of orientation processing in generating the eggs illusion. 
RD 4/15/2021
UL https://doi.org/10.1167/16.15.27