When you stare at the picture for about ten seconds you eyes adjust to this negative image and then the picture changes to black and white but you don't see it as black and white you see it in full color. Amazing!
Have you ever seen an optical illusion? Of course you have you're on Optical spy. Maybe an image of never-ending stairs that seem to merge into one another at different angles and all lead to the same way, over and over again!
Most optical illusions are tricks of the mind and depend upon how you perceive the image you are seeing. An optical illusion is an occurrence where you perceive and see an image that is an illusion; you see a virtual reality that exists only in your mind.
In general, optical illusions are of three types, but here, we will discuss only the physiological illusions that occur as physical responses of the eye’s exposure to light, and other stimuli.
What Are Physiological Illusions?
When we look at a bright light bulb for a long period of time and then look away at a dark surface, we can clearly see the imprint of the light bulb in front of our eyes. This is the physiological illusion that our eyes create when they are over exposed to the stimuli of lights.
Thus, all such after-images that flood our vision after our eyes have been stimulated with a stimulus, are known as physiological illusions.
Cause of Physiological Illusions
Physiological illusions are caused by a wide variety of stimuli, out of which the most common ones are brightness, movement, tilt, color, position, and size. These stimuli send messages to the brain and create an impact that can be seen even when you have taken your eyes off the image itself. Just like the bright after images seen after staring at a light source for long durations, similarly, even starting at a pattern can cause you to visualize it in continuous succession even when you have stopped looking at the image itself.
The theoretical reasoning behind physiological illusions is that certain images send stimuli to our brain using fixed neural paths. Thus, when you continue to stare at the image for a longer duration, your eyes are repeatedly receiving stimuli from the image that is being transmitted to the brain via the same neural path over and over again. This is what creates a pattern or imprint in front of your eyes and hence, when you remove the image from your line of vision, you can still see it in front of your eyes.
A physiological illusion is thus, considered to be a physiological imbalance that actually alters and changes your perception, making you see images that are not present in front of you. You can even see the physiological illusion when you close your eyes as the world becomes dark behind your eyelids.
Physiological Illusions and Art
As most techniques of illusions, physiological illusions are also greatly used within the works of art of various past artists. People from many genres and styles of painting have made the most of illusion artwork by creating images that stimulate the eye and create long lasting illusions.
The use of bright colors and alternating patterns helps these talented individuals in creating vivid pictures that come alive in people’s eyes with the help of a physiological illusion.