A mind-boggling optical illusion is really powerful when you see it – it’s the psychologist’s favorite party trick

THE old cliche says, “Seeing is believing,” but one psychologist’s popular optical illusion challenges that adage.

In just a few seconds, this visual trick turns a black-and-white photo into a full-color rendition of a happy campus scene.

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Steve Rathje is a psychologist and PhD student in Cambridge who breaks down psychological phenomena for his 1 million TikTok followers.

In a recent video, Rathje demonstrated his go-to-party trick, coloring a black and white photo in seconds.

“I’m about to trick your brain into believing that this black and white image is entirely in color,” Rathje said at the beginning of the video.

He then asked viewers to stare at a spot in the center of the image for 20 seconds.

The image in question wasn’t black and white, but an odd version of the earlier monochrome photo, featuring purple grass, an orange sky, and other unusual details.

Rathje explained what would happen while his viewers stared at him.

“The color cells in your eyes, called cones, get tired,” the psychologist said.

“When your cells get tired, they send out more activity for the opposite color.”

As long as viewers continued to stare at the designated spot, their eyes produced “reversed” afterimages.

The orange sky would create a deep blue afterimage, while the warm purple of the grass should turn green.

After the “inverted” image was shown for 20 seconds, Rathje again showed the black and white image.

“Here is the black and white picture,” said Rathje. “It shouldn’t look black and white to you.”

Instead, viewers saw a full-color scene, and several people in the comments expressed their awe at the effect of the illusion.

“The grass was so bright green. So cool!” wrote one viewer.

“It worked so well I had to move my eyes to see if it was really black and white,” said another viewer.

Some commenters struggled to see the image but were successful by holding their phones further away or pulling up the image on a larger screen.

Those who were able to successfully see the illusion couldn’t wait to pass it on.

“This was so cool I had to share this with my daughter,” wrote one viewer. “Thanks!”