Sometimes our brains want us to believe and see things that aren’t really there. Take a look at these 40 optical illusions that will really mess with your brain.

Cornsweet Illusion. These squares look like two different colors, right? They are actually the same color. Hold your finger over the line that separates the two shapes and you’ll see the change.

The Ponzo Illusion. These 3 cars look like different sizes, right?

They are actually the same size. Our brains judge size based off of it’s perceived distance.

These dots looks like they are changing color and orbiting the middle, right? But focus on just one single dot… they don’t change color or rotate at all.

State at the blinking green dot for a few seconds and then see what happens to the yellow dots. Believe it or not, the yellow dots never actually disappear.

Similar to the example above, stare at the cross and watch the blank spot.

What appears to be a large 3D globe…

is actually completely flat.

Which orange circle looks bigger?

They are actually the same size. This is called the Ebbinghaus illusion that shows when an object is surrounded by larger objects, it makes it appear larger.
Stare at the yellow dot and then move your head closed to the screen and the rings will begin rotating.
Hard to believe, but squares A and B are actually the same shade of grey.
Here’s the proof. Since B is in the same shade of the green cylinder, our brain believes its a lighter shade of grey.
Look at this picture for 30 seconds and then look at the picture below.
That was your eyes trying to regain composure.
This is called the “Ames Room” illusion. It distorts your depth perception and is created by slanting the back wall of the room towards the camera and the ceiling downwards.
Think these yellow and blue blocks are moving one after another?
Nope. When the black bars are removed, you’ll see that they’re always parallel.
Slowly move your head towards the image and the light will get brighter and vice-versa. This is called the dynamic-gradien affect.
Stare at the center of the colored version, then wait for it to change to black and white. Instead of seeing black and white, your brain fills it with what it thinks it should be seeing.
Even though some dots appear black, they are actually all white.
Here you can see animation just by used a black card.
See how these dinosaurs eyes appear to be following you. This is called the “hollow face illusion”. This works because our brains perceive objects differently when we recognize them as faces.
These images are not animated or moving at all. They appear to be moving because of the geometrical shapes, brightness and colors.
Same as this one.
And another.
Photographers layer multiple images on top of each other to create two-faced portraits.
Which way is this train going? Are you sure?
You can control which way the middle dancer spins by looking at the left or right dancer.
Here 3D art looks impossible.
This is actually an image of two people kissing, not someones face.
The photo on the right appears to lean more towards the right. In reality, they are the exact same images.
Even though these lines appear to be sloping, they are actually parallel to one another.
These circles appear to be overlapping. They are actually perfectly round and don’t touch each other at all.
Cross your eyes and you should recognize this face.
Stare at this lady’s nose for 10 seconds and then blink rapidly. You should see her appear in full color.
Source: Distractify
It’s pretty awesome what our brain thinks is going on and what’s really going on with these illusions. Imagine how many things we see on a daily basis that aren’t as they appear.