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This optical illusion will determine if you have "curvature blindness"

Call 999 now! I have curvature blindness!

This optical illusion will determine if you have "curvature blindness"
12 September 2018

Love a good optical illusion, so we do - love just looking at something and our brains going all funny. Remember when Magic Eye was absolutely everywhere? Fun times.

And we’ve got a good one for you today, and one that will specifically tell you if you posses a certain condition called “curvature blindness”.

So take a look at the picture below:

Do you see:

a) a load of curved lines

b) a load of jagged diagonal lines

c) both

d) a dolphin

If it’s c, then you have “curvature blindness” (if it’s d, erm, go to a doctor).

Now, look at the white and black areas in the corner of of the image and you’ll notice that both lines are actually smooth curves all the way through, it just starts to look all jagged and weird in the grey area. Don’t fret though, most people see the image this way, so you don’t need to rip your eyeballs out or anything.

Experimental psychologist Kohske Takahashi, from Japan’s Chukyo University, discovered the illusion, and says:

“We propose that 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.

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“I’d say that our eyes and brain may have been evolutionarily adapted to detect corners more efficiently than curves.

“We are surrounded by artificial products, which have much more corners than [the] natural environment does, and hence our visual. This visual phenomenon doesn’t cause the problem in our everyday life, otherwise someone should have found this illusion earlier.”

But whhhyyyy?

Well, it’s all to do with the peaks and troughs and the fact that they are accentuated by the light and dark areas in the “curved” lines, but the approach and descent are highlighted in the “jagged” lines (they’re both actually curved though, obv), accentuating the “straight” edges.

So now you know.