

Optical Illusion: Here are 8 intriguing optical illusions and mind-boggling illustrations
When you’re living in a social media age, we’re all too used to manipulated, photo-shopped images going viral online.
But some of the trickiest and most confusing pictures and illustrations out there have existed for centuries.
Optical illusions, perhaps more commonly known today as visual illusions, are images that use artistic, photographic or psychological techniques to play with visual perception – with confusing images causing slippages between the eyes and brain as we try to interpret them.
Writing in scientific journal Trends in Cognitive Science in 1997 the late Professor Richard L. Gregory said: “Visual illusions provide evidence of perceptual processes, especially the use of knowledge about objects and the working rules for seeing.”
Here are 8 visual illusions that will have your eyes – and mind – playing tricks on you.

1. Scintillating Grid
Look at one of these circles too long and you'll find those surrounding it flashing grey or black, while they are all in fact white. Photo: pixabay

2. Kanizsa Triangle
First created in 1955 by Italian psychologist Gaetano Kanizsa, the Kanizsa Triangle creates the illusion of a triangle in the centre of the image when there isn't one. The effect is instead created by subjective contours. Photo: JPIMedia

3. Rubin's Vase
This legendary illusion has some viewers first seeing vases or chalices, while others might see at its edges the outlines of two human faces to experience the 'Gesalt Switch' and change of perspective. What do you see? Photo: Getty Images via Canva Pro

4. Mermaid or Fish?
This illusion went viral in 2022, with the traditional seal or donkey illusion taking on a new life of its own as many said they could see a mermaid or fish in the illustration. What can you see? Photo: Twitter/Canva Pro