Optical illusions are a great way to challenge your eyes and brain, as they can sometimes be really challenging to work out.
Good observation skills and a keen eye for detail are essential when it comes to understanding them, and there's nothing more satisfying than finally cracking it.
But some require more than just good eyesight, as an optical illusion recently shared on social media can apparently only be worked out by the smartest people, the Star reports.
According to PinkVilla, who shared the image on Instagram, the cleverest people with strong eyesight and the highest IQs are most likely to understand the optical illusion.
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