Illusions rotate in a strange way

A whirling illusion makes each observer see a different hue and so far, no one knows why there is such a phenomenon.

When you stare at the black and white wheel whirling around long enough, you can see a certain color appear. Particularly, different people reported observing different colors, while some said they didn't see anything.

Many virtual observers say, they see green, others say they see yellow and some say red. However, exactly why this phenomenon happened, is still a tough question for the scientific community for decades.

The virtual wheel is called Benham's spin , named after American toy manufacturer Charles Benham, who created it in 1895. The turning of Benham creates the illusion of color when the patterns are black and White changes constantly, quickly. When the wheel rotates, subtle colored arcs, called Fechner colors, appear in different areas on the wheel surface.

The faster the rotation speed, the more obvious the color effect is. Reversing the rotation of the wheel can also change the observed chroma.

One theory for why people see different colors is that, receptors in the human eye react at different speeds before red, green and yellow.

The retina in the human eye consists of two types of light sensitive receptors, cones and rods. Cone cells play an important role in the ability to observe color and glare. There are 3 types of cone cells and each is most sensitive to a certain wavelength of light.

Researchers at the University of Washington (USA) said that different colors were observed when the baby turned Benham twirled, possibly as a result of changes in the retina and other parts of the system. sight. For example, whirlpool discs can activate different areas of the retina or the black and white areas of the disc stimulate different parts of the retina. This reaction is thought to cause a form of change in the nervous system, creating different colors that the subject sees.

Another theory is that different retinal cones maintain activation during different time periods. That means, when the wheel rotates, the white areas activate all three types of cone cells and then the black areas cause them to stop working. This order can cause an imbalance, because cone cells have different reaction times, leading to the brain producing different colors.

Although the above hypotheses cannot fully explain the illusion, Benham is still being studied for use as a diagnostic tool for eye diseases.