In an annual contest held by the Neural Correlate Society, fans voted the Changing Room Illusion one of the top three most impressive optical illusions of the year. Cohen, an assistant professor of psychology, created the deceptive video as a demonstration of “gradual change blindness.”
The video at first appears to show a static, unchanging photograph of “the waiting room of a science laboratory.” At the end, however, the video reveals how multiple objects in the room have slowly changed color, shifted location or disappeared entirely, in a way that may have been difficult to perceive as it was happening.
“While trying to prepare a novel example of this phenomenon for students, I realized that I could change dozens of items without observers noticing," says Cohen, who teaches courses on cognitive neuroscience and whose research explores visual perception, memory, and awareness.