7 trippy optical illusions that reveal how your brain perceives reality

Seeing is believing? Things aren’t always how they appear. by Jennifer Walter Updated: Feb. 20, 2024 Originally Published: June 23, 2022 Akiyoshi Kitaoka

Shutterstock If there’s one thing optical illusions can teach us, it’s that we can’t always believe our eyes.

The clever tricks that illusions play on our brains help unravel how we perceive the world. They’re not just fun to look at, but researchers often make and study new illusions to better understand human perception. Shutterstock

Akiyoshi Kitaoka Psychology professor Akiyoshi Kitaoka of Ritsumeikan University in Japan is a well-known creator of stunning optical illusions who also studies their effects.

He documents recent creations on Twitter and his website in what feels like an endless stream of fascinating mind tricks.

Akiyoshi Kitaoka Here are 7 of Kitaoka’s recent mind-bending illusions:

7. Do these snakes seem to ... slither a bit?

Believe it or not, the snakes actually aren’t moving — that’s just your brain perceiving a lateral shimmy.

Notice how only the snakes in your periphery appear to move, but the one you look at directly does not.

This effect is called peripheral drift , and is also present in Kitaoka’s famous Rotating Snakes illusion.

6. Focus on the black gaps.

Did they appear to expand? That’s the intended effect here — and other illusions can create a similar sensation as well.

5. Now try staring into this black hole.

This illusion was recently the subject of a scientific report that found it causes viewer’s pupils to expand.

Researchers think this reaction is due to the brain anticipating a sudden plunge into darkness. Thus, the eyes begin to adjust in order to prevent you from being caught off guard by the light shift.

4. Be still, my beating heart.

The heart isn’t animated, but it does appear to shake slightly, thanks to carefully-placed colors and lines that trick the brain into perceiving motion.

3. What color are these strawberries?

Akiyoshi Kitaoka If you guessed red, you’re actually wrong. Up close, the tip of the strawberry (below) consists of yellow, blue, and black stripes.

You can thank color constancy in part for this eye trick. Our brains perceive colors by contextualizing them with colors and objects in the vicinity, which comes in handy when we see objects in different lighting.

This is a variation of a viral illusion that Kitaoka posted to Twitter in 2017, in which the strawberries were actually gray.

2. Are these swirls tilting?

Akiyoshi Kitaoka Though the swirls are in perfectly aligned columns, the black and white darts placed between each one help make it appear like they’re tilting.

1. Stare at the plus sign in the center for a few seconds.

For some people, the colorful dots will start to disappear.

This is a demonstration of the Troxler effect , which causes visuals in your periphery to vanish when you fix your gaze on one part of an image.

If the dots illusion doesn’t work, try gazing at the plus in the center of the Cheshire Cat’s face — eventually, even its cheeky grin should disappear.

Ignaz Paul Vital Troxler (1780-1866)