Stereoblindness is an extremely unfortunate condition where someone cannot perceive depth correctly. Bruce Bridgeman was one such individual, having an eye condition which prevented him from developing functioning binocular vision. In essence, he was living in a "flat" world.
"When we'd go out and people would look up and start discussing some bird in the tree, I would still be looking for the bird when they were finished," he told BBC. "For everybody else, the bird jumped out. But to me, it was just part of the background."
That is, until he stepped into a theater to see Martin Scorsese's Hugo in 3D. He stepped out with a truly different outlook. The 67-year old neuroscientist took his wife to go see the 3D film, despite realizing it would be completely wasted on him. However, to his surprise, as the movie progressed he was able to perceive more of the stereo effects.
"It was just literally like a whole new dimension of sight. Exciting."
He was even more pleased to find that upon leaving the theater, the effect stayed with him.
"I was astonished to see a lamppost standing out from the background. Trees, cars, even people were in relief more vivid than I had ever experienced."
Scientists still aren't completely sure what about the film caused this, but there is some precedent for the transition. Most famously, a woman in 1970s was cured of her stereoblindless through vision therapy.
Some think that Bridgeman's brain already had the capacity to see in stereo, and something about Hugo's particular use of 3D trained his eyes and brain to work together in order to see properly. It's certainly an exciting, almost unbelievable story, and I would be very interested to see how this might effect neuroscience and vision treatments in the future.
One thing's for sure though—everyone with stereoblindness will be hitting up the next 3D movie.