You may have seen this one before but the image of a pair of Vans shoes that appears as different colours to different people has stumped a pop star too.
It seems none other than singer Lizzo has joined the confused among us, retweeting the viral image with an added twist: this one claimed people whose right side of the brain is dominant will see pink and white, while the left-brained will see grey and green.
"I see grey and teal what colour do u see?" she wrote.
• Superstar Lizzo to play Auckland's FOMO Fest with Brockhampton, Kaytranada
• Album review: Lizzo, Cuz I Love You
• Hot Takes: George the Poet, Line of Duty and Lizzo
• Hot Takes: Lizzo, The good Place, Pleasuredome and more
"Right-brained" people are said to be more artistic or creative, while the "left-brained" leading tend to be more logical and methodical, although there's limited medical evidence to support this.
The image the caught the attention of Lizzo isn't the first time a picture has left people wondering if their eyes are deceiving them. A few years ago a photo of a mother-of-the-bride dress circled the internet, leaving viewers divided over whether it was blue and black or white and gold.
According to a New York University study of over 13,000 people, the colour combinations identified in the dress image were found to be linked to people's internal body clocks.
Those who woke up earlier tended to see the dress as white and gold, while night owls saw it as blue and black.
Our internal body clocks affect how we see light. People who wake up early tend to spend more hours in sunlight, while those who sleep in are more exposed to artificial light.
This might also explain the image of the shoe better than putting it down to which side of the brain is dominant.
The light we're most exposed to influences how we perceive colour - and with overexposed images like those of the dress and the shoe, our eyes make assumptions about the photos' light sources.
That's not to say our dominant side of the brain may not also be a factor.
Either way, these images are sure to keep cropping up online, sparking confusion and fascination all around.