Here’s a fun trick – but be forewarned – it’s gonna freak you out.
Stare at the red dot on the woman’s nose for 30 seconds. Then look at a blank wall and blink repeatedly. Whoa! Sit back down and calm your heart. It’s only science (see explanation below).
This optical illusion uses a negative image of a woman’s head. If you stare at the dots for about 15 seconds, then look at a blank wall, you’ll see a full-color image of the same picture (well, at least most people will see it. Those with cosmic superhero eyes will just see right through the wall). Why does this happen?
This illusion is known as a negative afterimage. Our eyes have cone cells called ganglion cells that help us see pairs of primary colors. We have channels in our eyes for black and white, red and green, and blue and yellow. The blue and yellow pair is what makes this optical illusion work.
The cells for blue/yellow focus on the blueish areas of the picture and become overstimulated. When we look to a blank background (e.g. a white wall), those cells quickly decline, sending out a much weaker signal, and as a result, our brains interpret the signal as the opposite color – in this case, yellow. The hues of yellow are added back into the picture giving us the “normal” skin tone we would expect to see in a picture of a person.
For those with X-Ray vision, we’re sorry you’re missing out on the effect but hey, you get to see people walking around in their underwear all day so stop complaining.