You have 20/20 vision if you can find the animal hidden among the lines in this optical illusion within 20 seconds

READERS might say they have 20/20 vision if they can spot the hidden animal in this fiendishly difficult puzzle.

Spectators struggle to spot the cat lurking behind the black and white lines.

Can you find the cat in this illusion? Credit: Twitter/medkinson

But they face a race against time as they have been challenged to spot the cat within 20 seconds.

Heads spin after scanning the black and white image.

The cat is very difficult to spot, but just shaking your head is enough.

If you shake your head frantically, you should be able to see the animal’s piercing eyes before you recognize the facial features.

The stunning illusion went viral, with social media users commenting on how they managed to spot the cat.

One Twitter the user said, “Just shake the phone. It’s lighter than your head.”

Another claimed: “I can see it without shaking my head or phone, with both eyes open or even one eye closed.”

Players said that tilting their phones is a preferred option, especially when they are out and about.

While social media users said they felt nauseous after trying to spot the cat by shaking its head.

Some said they could see the creature without shaking their heads or tilting their phones.

If that illusion has you stumped, then why not see if you can spot a deadly sniper prowling the mountains in less than 20 seconds?

Readers looking for a challenge should see if they can find the hidden letter Y in this puzzle within five seconds.

Viewers might say they have 20/20 vision if they can spot the number eight in this math-themed puzzle.