Christmas is a time for contemplation, sharing presents and enjoying time with loved ones. Not for being bamboozled by optical illusions. But hold the eggnog and turn off the Strictly special because this Christmas optical illusion is a mind bender.
You see those two red snowflakes in the image below? They're different sizes, right? But no. We're told the two snowflakes in this optical illusion are actually the same size (if this festive fun has got you in the mood for more, see our pick of must-see optical illusions).
So there I was with Christmas all planned out, ready to settle down for the Great Christmas Bake Off and an episode of His Dark Materials, when a company called Jackpotjoy sends us an infuriating optical illusion to keep us entertained instead. The image shows a bunch of festive snowflakes on a blue background. There are two red ones snowflakes: one surrounded by six large white snowflakes and the other surrounded by eight small snowflakes.
Those red snowflakes appear to be different sizes. But we're told that no, they're actually identical. Any confusion is not due to one too many mimosas but due to something called the ‘Ebbinghaus effect’, named after the German psychologist Hermann Ebbinghaus. He described how identically sized objects can appear larger or smaller than each other due to relative size perception.
Basically, our interpretation of the size of an object is affected by its proximity to others. When the surrounding white snowflakes are closer to the central red snowflake, it appears larger and vice versa. Our brain tells us that the red snowflake on the left must be smaller, because it is far away from the white ones around it. The white snowflakes on the left are also much larger, making the red one seems small in comparison.
Now, I thought that maybe they were trying to pull a fast one on us here, so I dragged the image into photoshop (sorry guys, I had to check) to get rid of those pesky white snowflakes that are confusing us. And sure enough the two red snowflakes are identical.
Now, apparently in a test of 95 people, eight out of ten were fooled by the image. They don't say whether this was before or after the work Christmas party, but the statistic should offer some comfort to anyone bamboozled by this optical illusion. If it's left you in the mood for more, see our pick of the best optical illusions of the year. Or see if you can design your own using the best graphic design software.