Only one per cent of the population can find all the triangles in this optical illusion

There's an ongoing fascination with optical illusions, and while they're all in the name of fun, they also hold some real value to scientists.

Discussing the importance of optical illusions to understand our brains better, scientists Kim Ransley and Alex O. Holcombe of the University of Sydney told The Conversation: “Visual illusions show us that we do not have direct access to reality,”

“They can also provide an inkling of the mental processing that delivers our experience of the viewable world.

“Indeed, it is the processing happening inside our brains that is the basis for many illusions.

“Rather than delivering information from our eyes in nearly raw form as a camera would, the brain tries to determine what is actually out there.

“When the information entering the eye is ambiguous, the brain must make educated guesses.”

Apparently, only one per cent of people can get this optical illusion right.

In a viral TikTok that's racked up 1.6 million views, Hectic Nick (@hecticnick) shows an image containing several triangles: "It sounds simple, but it’s not easy," he said, "Let me know how many you think there are.”

Take a few minutes to count the triangles in the image below:

@hecticnick/TikTok

Fellow TikTok users flocked to the clip with their takes, with the most popular answer being four. Others guessed between seven to 15 triangles.

None of which are correct.

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The answer...

The correct answer is 18 – and if you managed to guess correctly, congratulations – you're in the top one per cent.

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