A bizarre optical illusion is dividing opinion among puzzlers who can’t seem to agree whether the image is really a moving GIF.
The static picture, which features a grey square made from smaller grey squares, appears to move with each scroll of the mouse.
However, in reality the picture remains still with the sense of movement just a fiendish trick of the viewers’ brain, which fails to process the image with each scroll of the page.
Now, with over 25,000 upvotes on Reddit, users have been battling it out in the comments – with many disagreeing over how the image appears to be moving.
The static picture, an anomalous motion illusion, appears to move with each scroll of the mouse when it is in fact static
What is an anomalous motion illusion?
Anomalous motion occurs when some parts of a moving image appear to lag behind other parts of the moving image.
That is, some parts of a moving image will appear to continue moving for a short period of time when the rest of the image stops.
When the image first starts moving in the opposite direction, a part of the image will momentarily remain still.
The image captioned: ‘This is not a GIF’ left some users feeling motion sick, with one commenting, ‘I don’t feel so good’.
While another user shared what they believed to be the reason behind the confusing illusion.
They commented: ‘Had to zoom all the way in to figure it out – the centre square is the same pattern as the outer area, but rotated 90.
‘For some reason the shadow pattern being rotated makes brain brain go pop.’
Another came to the same conclusion and wrote: ‘It looks like the way the middle piece is cut before its rotated makes your brain try to piece it back together.
‘The angle of cut+ 90 degree rotation = brain confusion.’
Meanwhile, a further suggested a colour theory behind the illusion.
They wrote: ‘For anyone who cares, the color contrast between dark and light causes the optical illusion, also known as anomalous motion illusion.
They added that they believed Japanese psychology expert ‘Akiyoshi Hitaoka was involved in its creation.’
One creative user asked: ‘Can this image get the same effect as a tattoo?’
The puzzle, which has been circulating on Reddit, has 25,000 upvotes – with many disagreeing on the reasoning behind the confusion
Here, another anomalous motion illusion appears to wave. On each green square intersection is a white or pink shape, which looks a bit like a plus sign. This is what causes ‘movement’