Interesting effect.
The Lurking Pornographer: Why Your Brain Turns Bubbles Into Nude Bodies
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.