We don't think about it, but there are a lot of folks out there that don't see in three dimensions. They had cross eyes or lazy eyes as a child, and thought they probably had surgery to correct the condition, they still have the condition called "strabismus", where the eyes don't focus together on points in space. Instead, one eye focuses and the other effectively turns off.
It was thought that after a certain developmental period, the brain could not develop stereopsis, according to Barry. That, and a sort of disconnect between opthalmologists (medical doctors) and optometrists (they go to optometry school) that has prevented more treatment.
Barry, a neurobiologist at Mount Holyoke, diagnosed her condition, and was very proactive in finding someone with the tools to change her brain patterns. After being profiled in the New Yorker article "Stereo Sue", she became in touch with many folks who shared her condition.
In some way, she got the idea that the body adapts from her husband, Dan Barry, an astronaut, and how he became a science project for her daughter. His body learned to adapt to zero gravity, but at first there were things he couldn't do when he returned to normal conditions.
You really can't understand what it feels like to go from mono to stereo without it happening to you, but Barry gives a good try (I read the book, and I appreciate that she made the effort). Like me, you may realize partway through the book that you know someone with this condition (he's now getting Fixing my Gaze as a gift). I think the other part of the issue is that doctors don't realize how desperate folks with strabismis are to see in stereo, and that's why they dismiss cures. I have no idea. But the man who developed the treatment, Frederick Brock, was a sufferer himself, and he was the first patient he treated.
Susan Barry (who looks so much in this picture like her brother, Daniel, one of my favorite customers) is speaking at Boswell on Tuesday, January 12th, at 7 PM. Here's a link to praise from the general and scientific press for Fixing my Gaze. Can't come? You can also watch a lecture on Youtube.