This post was originally published at the James Randi Educational Foundation
There is a pornographer lurking in some corner of your mind. He peeks out from behind the curtains of your consciousness without warning, and almost never at an acceptable time.
The lurking pornographer in your brain is ever vigilant, looking for patterns, for signs of nudity, and sometimes generating them out of nowhere. He is exceedingly good at what he does, and isn’t afraid to prove his power over your perception. Just like that, he can take a picture of Daniel Craig in a bathing suit and turn it obscene.
If anything, Craig is more covered than he was before, but still he must be nude in the new picture, or so the pornographer would have you believe. The pornographer is sly. He takes advantage in the slightest slip in shapes and curves to insert his nudity. One of his favorite techniques is called “bubbling,” a technique that reveals how our brains actually “see.”.
Breasts and Blind Spots
Stifled by the pornography-restricting tenets of his religion, a young Mormon took to Photoshop, or so the story goes. His attempt to fool God and circumvent his law resulted in “bubbling,” a trick clever enough that how it works hasn’t yet been answered.
You eye doesn’t see everything. Right now, there are innumerable photons hitting the photoreceptors all over your retina, except in the place where your optic nerve connects to it. This area is your blind spot, and it should show up as a rather large black dot in your vision, but it doesn’t. Why not?
As your brain matures, it learns from the world. Neuronal connections are formed and broken in accordance with the deluge of information your brain receives. Over time, your brain becomes adept at predicting the world, so much so that much of our conscious lives are spent only noticing when things aren’t going as predicted. For example, there was probably a time when you got out of the car and realized you have almost no recollection of the drive you just took. It seemed automatic because it was. Consciousness didn’t need to intrude during something so routine, so it didn’t. However, introduce a near-collision into your daily commute, and consciousness quickly steps up to handle the situation.
Based on all the shapes and colors and lines and lighting schemes that your brain has encountered, your cognition makes predictions about how things will look. The surprising part is that this “software” is even good enough to fill in areas that we in fact cannot see. There is no better example of this than the blind spot test.
Cover or close your right eye and look at the cross with your left eye. Move closer and closer to the screen (likely ~12 inches away) until you see the dot on the left disappear. This is your blind spot. This is where you aren’t getting any optical information, but merely the dot vanishes, not the world. No matter the background nor the pattern nor the shape, your brain will fill in the blind spot with what it sees around it, in this case the white screen. To prove to yourself how good the brain is at filling in the world, try this test involving multiple versions of the blind spot test.
The Easiest Assumption is Genitalia
The pornographer lurking in your brain has been especially aware of human nudity since your birth. A likely outcropping of evolutionary pressure on reproduction, he looks for the body parts we try to cover up at every turn. He is familiar with nudity, but not with swimsuits.
Like how the brain fills in the background in the blind spot test, your brain makes a prediction about what is behind the bubbling when all it can see is bare skin. To the brain, a continuation of bare skin is more likely than one of the infinite variations of bathing suit. Moreover, the unconscious isn’t nearly as bound by social convention—given the choice between a naked human and a clothed one, the assumption goes the pornographer’s way.
Bubbling gets its name from the clever use of circles to obscure people’s clothing in photos. But the technique isn’t as clever as you may think. Any way to cover all of the clothing on a person’s body while leaving the bare skin should produce a similar assumption of nudity. For example, comedy shows regularly blur out the genital regions of actors who aren’t actually naked, still producing the illusion. A black “censored” bar over the suit of Daniel Craig above would still seem risqué.
You can’t control your blind spot, and neither can you control the lurking pornographer. He is cemented in your subconscious, laboring away at any pattern or shape that could be construed as indecent. But he is only one of many pattern-seekers. He sees genitals, but others see faces.
So, don’t feel bad about where your mind goes, it’s just a product of a predicting and pattern-seeking brain. We fill in the blanks all the time, but sometimes it’s dirty.