India, Oct. 22 -- Optical illusions are pictures or patterns that trick your eyes and brain. They make you see something that looks different from what it really is.

These illusions show how our mind can be easily fooled by shapes, colours, or angles.

Here's an optical illusion that challenges viewers to spot a hidden dog in a mind-bending image of what first appears to be an old man with a beard.

The optical illusion was shared on Instagram by @fortbendmd, with the caption, "Only 1 out of 5 spot the dog hidden in this drawing of a man's face: Are you one of them?

At first, the illusion appears to show an old man with a beard, perhaps squinting or deep in thought.

But there's a hidden surprise, the challenge is to spot the dog hidden...