A new optical illusion has been discovered, and it’s really quite striking. The strange effect is called the ‘curvature blindness’ illusion, and it’s described in a new paper from psychologist Kohske Takahashi of Chukyo University, Japan.
A series of wavy horizontal lines are shown. All of the lines have exactly the same shape – a sine curve. However, half of the lines appear to have a much more triangular, “zig-zag” shape, when they are superimposed on a grey background. This “zig-zag” appearance is an illusion.
…
So what’s going on here? Takahashi proposes that the brain’s visual system may default to seeing corners when there ambiguity over whether a line is a smooth curve or not:
The underlying mechanisms for the gentle curve perception and those of obtuse corner perception are competing with each other in an imbalanced way and the percepts of corner might be dominant in the visual system
…
Takahashi notes that the illusion involves a sense of depth: the “zig-zag” lines look a bit like a surface, or wall, going into and out of the page, and the changing color of the wavy line suggests shadows. However, further experiments revealed that depth perception is not the driving force behind the effect.
Read full, original post: The Remarkable “Curvature Blindness” Illusion
