A new study has discovered a new type of optical illusion and it will make you question everything.
It's called 'curvature blindness'.
Picture: Takahashi (2017), Iperception
Yup, it sounds and looks dull at first.
Until you are told that this isn't just a bunch of curvy and zig-zagged lines; in fact, all the lines actually have exactly the same shape: a sine curve.
Yet when the lines are on a grey background, half of them look as if they have a 'zig-zag' shape.
The paper's author, psychologist Kohske Takahashi, wrote:
As the effect magnitudes are quite strong, unless one carefully stares at the region that looks like a corner, it is hard to find that all lines are physically wavy.
Despite the simplicity and effect magnitudes, to the best of our knowledge, no one has reported about this phenomenon.
It is not clear why the brain perceives the images this way. But Takahashi theorises that 'obtuse corner detection' might have something to do with it.
Essentially, when confused over whether lines are curved or not, the brain assumes a zig-zag shape to make life easier.
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.
It is only when the lines have a dark line that runs from the crest (or peak) to the trough that this illusion takes effect.
These lines are shown in the black boxes:
Picture: Takeshi (2017), IPerception
When the dark segment reaches the crest of the wave, the lines appear curvy across the entire image.
Now it's time to ask what else in your life is a lie.