Coca-Cola Can Optical Illusion Will Have You Seeing Red, Literally

Photo 278091649 © Bigtunaonline | Dreamstime.com

Here’s a zesty palate cleanser for the eyes. Akiyoshi Kitaoka, a psychology professor at Ritsumeikan University in Japan who is known for his brain-bending optical illusions, is opening a big can of curiosities with what looks to be red Coca-Cola packaging. In reality, there’s no red in this picture at all—just cleverly used black, white, and cyan.

Previously, Kitaoka made waves with a playful image of gray strawberries that also looked red. In the new visual, cyan once again throws a curveball to our minds, which usually expect to see a red can of Coke. This expectation is what prompts the brain to see red where there is none.

The principle at play involves a phenomenon known as color opponency, which tricks our brain into seeing hues that aren’t there, particularly when high contrast is involved. The cyan in the image acts as a visual adversary to red, fooling our brains into filling in what we believe should be there, based on the iconic branding of the soft drink.

You may see a Coca-Cola can reddish, though this image consists of black, white, and cyan (no red). pic.twitter.com/OOXwmONV0o

— Akiyoshi Kitaoka (@AkiyoshiKitaoka) December 18, 2023

The illusion also taps into the brain’s knack for color correction, where it compensates for light conditions to maintain consistency, leading us to perceive the red we expect from a Coca-Cola can.

This effect could be heightened by the fatigue of our eyes’ photoreceptors after staring at one color for too long, leading to the appearance of its opposite color in our vision.

OK, you’re absolutely right. pic.twitter.com/tZSgCUh3WE

— Rydeen (@Rydeen) December 18, 2023

Furthermore, the power of expectation shapes our reality; we often see what we believe we should see. This cognitive bias is at the heart of this bamboozlement, challenging viewers to question the certainty of their own vision. Perhaps it’s also a testament to how unshakable the Coke image is. 

[via Boing Boing and Akiyoshi Kitaoka, images via various sources]