Take a good look at the image above and focus on the point at its center. Do not blink.
In less than half a minute, you may notice that the pattern is fading. Lighter colors and shapes on the edges will be the first to disappear.
Within a minute or so, all images are lost and leave only a clean white or gray room without a pattern.
When you blink or attention is distracted, patterns like the ones you see at the beginning will reappear.
This optical illusion has a name and an explanation. Its name is the Troxler effect, taken from its creator who was a Swiss physician and philosopher who lived in the early 19th century named Ignaz Paul Vital Troxler.
Around 1804, Troxler found something interesting. As he focuses his eyes on one point, other elements in the same visual field will slowly fade and disappear.
Basically, the optical illusion Troxler finds does not really eliminate the image as we continue to see it.
To understand this optical illusion let's get acquainted with saccade.
Saccade is the unconscious movements made by the human eye, even when we are out of focus.
Fast eye movement allows the retina with all the light-sensitive cells to scan high resolution visual fields.
This is why when the focus retina sees a small dot in the visual field, the retinal light sensitive cells will only focus on something that does not change and slowly becomes insensitive to the stimulus.
The picture is just an illustration of how the brain overcomes thousands of constantly encountered sensations. This phenomenon is known as selective processing.
Unwittingly, the brain filters out foreign information so we just focus on the important things and will decide on unimportant forms of information.
When the brain ignores visual stimuli that do not change, the colors in the image above seem to fade and filled by the white color around it,
We may not realize something like this happens because the eyes and the environment are constantly changing.
This illusion is unusual because it directs our attention to one thing from so much attention and is supported by a blurry and faded image.
Selective processing may be more noticeable when it comes to other senses. This causes you to rarely smell perfume in a minute or two after use and you also do not realize how your clothes look when worn. This phenomenon also explains why we do not notice the presence of our noses.