Optical Illusion: What colours do you see?

Optical Illusion Grey Squares: A seemingly unbelievable optical illusion has left the netizens in splits. While some say that the optical illusion has different shades of grey, others argue that they are the same. 

Take a look at the image of two blocks on top of one another. 

 
What colour do you see? The two squares might appear to have two shades of grey but are the same. You might be wondering how? Here's an explainer. 

Optical Illusion: Check whether you have a more male or female brain

Grey Squares Optical Illusion Explanation

Place your finger in the middle of the two squares on the white portion. Do you notice something? The two blocks that appeared different until now are the same colour. 

Optical Illusion: How many legs does the elephant have?

The aforementioned optical illusion is known as the Cornsweet illusion. It is named after psychologist Tom Cornsweet who created it in the 1960s. The blocks appear different as this illusion works by contrast. 

Optical Illusion: Whose legs are whose?

Known for his works in visual perception, Cornsweet noted that humans perceive colour and shades of 3D images depending upon the way the item is in light and how the shadow falls on it. 

Can you spot the baby's head in the viral optical illusion?

If the light falls from the top left, the two squares appear tilted away from us. In this case, we notice the upper block as lit and the lower block in shadow due to the light source coming from the upper left of the image. 

If you combine the contrasting shading between the two blocks, our brain interprets the top block as dark and the bottom one as light.

Optical illusion: What do you see first - a man's face or someone reading a book? Here's your most annoying personality trait