What do you see? How optical illusions work - examples including ‘running man’ and ‘afterimage’
This optical illusion has gone viral and has been playing tricks on people’s minds
The running man, who may not actually be running, has divided the opinion of internet users.
The image shows the silhouette of a man who appears to be running, but is he?
Some people look at this image and see him moving, and some do not.
Here is everything you need to know about the latest in a long series of optical illusions that play tricks with our mind.
What is happening in the running man optical illusion?
The image shows the silhouette of a man behind some black bars. As the bars move, it looks like the man is running - but he is not.
The black bars in the image are moving from left to right, creating the effect of a running man, but as the bars begin to disappear - the ‘running’ stops.
When you reach the end of the animation, it is clear that the motion you thought you could see was all just a trick of the eyes and mind.
This type of illusion works by presenting a series of static images one after the other in quick succession, making the brain think that the image is actually moving.
This is known as the ‘persistence of vision’.
Afterimage optical illusion
Another mind-boggling illusion is the colourful, or black and white, parrot.
If you stare into the eye of the colourful parrot for 15 seconds, when the image turns black and white, you may still see some colour.
Your eyes make it appear as though the blue parts of the image are pink, and the pink parts of the image are blue.
Another tricky illusion is the turning circles with an interesting pink, blue, black and yellow design.
If you stare at the image for a few seconds, circles within look like they are slowly turning.
However, this is a mind game called illusory motion.
Some scientists believe that the objects appear to be moving due to involuntary eye movements
Other scientists suggested that the changes in neurons, which give the illusion of movement, can confuse the motion detectors in your visual cortex.
However, there is no correct answer.
What is an optical illusion?
Optical illusions can be seen within art, images, animations or pictures.
Optical illusions occur when our eyes send information to our brains that gets mixed up, causing us to think we see something that does not match reality.
These optical illusions are designed to trick you into seeing colour when there isn’t any, motion when things are still, and items disappearing from right in front of you.
There are two main types of afterimage: positive and negative.
In a positive afterimage, you are able to see the image in its original colours (even after the image colours have changed) because some cells on the retina continue to send signals to the brain.
Using the parrot as an example - in a negative afterimage, the colour you see may be inverted or reversed from the original picture.
Want more visual magic? Check out more mind-bending optical illusions.