Sometimes our minds (and ears) play tricks us on, especially when we're faced with a compelling visual or audio illusion. When those illusions get loose on the internet, they can spark viral warfare that splits friends and families apart as they argue over colors, words and what's hiding in that brick wall.
"Yanny or Laurel?" Them's fightin' words! The internet fell to pieces over an audio illusion that emerged in mid-May 2018 challenging people to figure out if a computer voice is saying "Yanny" or "Laurel."
As it turns out, even a bunch of experts aren't entirely sure why different people are hearing different words. (Even though it totally says "Yanny.")
Update May 16, 2018: Adds Yanny or Laurel, Soy Shape, oil legs, Mars cannonball and 12 dots.
In December 2017, A popular UFO enthusiast blog posted a close-up look at this spherical object spotted by NASA's Curiosity rover and suggested it is a cannonball left over from a war on the Red Planet. NASA's rover team responded with a Twitter message pointing out how the concretion is less than a quarter inch (5 mm) in size and is actually made up of calcium sulfate, sodium and magnesium.
This seemingly dull photo of a brick wall sent the internet into a conniption in May 2016 as it spread across social media. There's something else in the photo besides a stack of masonry. Some people see it almost immediately, for others it takes some time. Don't worry. Once you figure it out, you won't be able to un-see it. And, yes, it's pretty silly.
Visual-illusions specialist Jacques Ninio created this wonderfully frustrating take on a classic Hermann-grid illusion that makes dark spots appear in the crosshatches of a black-and-white grid. A partial version appears here, but be sure to check out the illusion in its full glory.
It spread across social media in late 2016 as friends challenged each other to spot all 12 dots at the same time. Good luck with that.
Pour yourself a side of optical illusion to go with your sushi. These impossible-looking shapes come from adding soy sauce to specially shaped dishes. Tokyo product designer Duncan Shotton calls them "Soy Shape."
This adorable cat entertains followers on Twitter. Owner Hanamomo keeps up a feed of kitty photos, but the markings on this particular cat make it a star. The buff-colored spot on its side is perfectly edged in black, making it look like it has a 3D hole where you can see the desert beyond.
The fancy feline is especially popular with Japanese Twitter followers, who discovered its unusual coloration in early 2016 and quickly shared the photos around the social-media site.
This Facebook post turned into a social-media frenzy in 2016. The challenge is finding the cell phone hidden within the image of a white table on a floral carpet. It may drive you nuts, but you won't be able to look away until you locate it.
Here are two legs. They're either shiny from being covered in oil, or they're streaked with white paint. It could go either way, but the actual answer comes in a clue seen in the background: paint pens. Instagram user leonardhoespams was responsible for starting the oil-paint controversy in late 2016.
The Best Illusion of the Year contest from the Neural Correlate Society is a gold mine for mental tricks. This illusion, called "Ambiguous Cylinder," was a runner-up for the 2016 contest. It comes from Kokichi Sugihara, an engineering professor at Meiji University in Japan. The illusion involves some very square-looking objects that appear to be totally cylindrical in a mirror.
This may look like a bunch of blue fuzz, but it's actually an optical-illusion image done in the style of a Magic Eye puzzle. Magic Eye illusions flummoxed and delighted lots of people during their heyday in the 1990s. Actress Blake Lively posted this puzzle to her Instagram account in June 2016 to promote her work in a shark movie called "The Shallows." If you're good with Magic Eye, then you'll probably be able to see the shark hidden here.
It's known simply as "The Dress." A photo of a two-toned frock sent the internet into a froth in 2015 as people disagreed about whether it was white and gold or blue and black. Everyone from scientists to celebrities shared their thoughts on The Dress and how so many people could have such different views of its colors. It comes down to how your brain interprets the photo, but it's more fun to argue your viewpoint than agree to disagree.
NASA's Spirit rover delivered an image in 2007 showing a view of craggy rock formations across the surface of Mars. One dramatically shaded formation stands out as it looks like a small statue of a walking woman. UFO blogs hailed it as a figure made by aliens, but the Planetary Society was quick to call the object an optical illusion and an example of pareidolia, the tendency for our minds to assign familiar patterns to random shapes or sounds.
Here's a picture of a cat walking downstairs. Or is it upstairs? That's the question that plagued the internet in April 2015 as people tried to decide which way the kitty was going. It probably helps that the photo circulating online is of a pretty low quality, which obscures any clues to the orientation. So which way is the cat going? That's up to you to decide.
These lamps from Studio Cheha look like they sport modern interpretations of classic shade designs, but there's a trick under way. Look at them from the side and you'll see they are actually made from flat acrylic glass etched to make them appear 3D from the right angles. Backers successfully funded the lamps on Kickstarter in late 2015.
This photo is a still from a video. It might not look like much at first glance, until you realize the boat in the center appears to be floating above the water. What's happening here is a type of mirage. The video is only a few seconds long, but that's plenty of time to witness the strange sight of a magical boat hovering out on the ocean. YouTube user Friends N Feeders originally shared the video in early June 2016.
This NASA photo didn't result in any social-media arguments, but it's still a looker. It shows Saturn's moon Dione as seen by NASA spacecraft Cassini. The perfect angle of Saturn's rings make it look like the moon is sliced in half and could be opened up like a plastic Easter egg. Cassini snapped the image in late 2015.
Art student Dain Yoon has a knack for creating fun illusions using her own body and some carefully applied makeup effects. In this image, she holds her hand over her face, but the hand seems to blend into her features as though it's transparent. Her top-notch painting skills make it work.