Eleven of our favourite mind-bending optical illusions

The below tweet from Kyle Hill got us thinking.

No, not thinking 'why does my brain hurt so much', but about some of our other favourite optical illusions. Let's get right to it.

The dinosaurs aren't actually moving

Skip to the 1:30 mark to see how it was done.

These circles aren't moving either

It's thought the way our eyes repeatedly scan images is behind the illusion.

Spotting a trend? This is a static image, not a gif

The two squares marked A and B are the same colour

Here's why.

Take another look at this elephant's legs

Sometimes our brain fills in the gaps when we expect to see something - even if it actually isn't there.

The disappearing chocolate bar

Here's how this one was done.

The circle in the middle is not changing size

These roads will really mess with your head

Stare at this heart - notice anything unusual?

This should definitely have been an emo band album cover.

You'll never look at Pac-man the same way...

With thanks to Illusion of the Year

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