Here’s an optical illusion that’s been making the rounds on social media websites for some time now. Basically, here’s how it works: Stare at the white dot on the blue woman’s nose for about 10 to 20 seconds. After that, look at the blank space to the right of her:
The blank face should turn into an image of the girl of a brunette woman.
The illusion, as Dr. Juno Kim of the University of NSW School of Optometry and Vision Science says, involves how humans perceive the world. People have three channels for seeing color, which includes gray-scale, red-green, and blue-yellow.
“When you look at something that, for example, is yellow for a long period of time, you stimulate the cells that are positively sensitive to yellow,” he told the Daily Mail in Australia. “When you then direct your gaze at a uniform background... the cell doesn’t return to its resting activity, it goes much lower than that,” he added.
