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NPR Report: Learning to See in Stereo


NPR’s Joe Palca was born with a crossed eye. So as not to be confused by two different images, his young brain learned to suppress the input from his right eye, leaving Joe with no stereo vision.

Conventional but false wisdom holds that after age 7, a child’s vision isn’t likely to improve. But researchers at the University of California, Berkeley, along with the COVD community, know that adults with the condition can improve their vision. Joe decided to go and meet them.

At the Berkeley lab, Joe was tested for stereo vision. After a couple quick tests, Dr. Dennis Levi, Dean of the School of Optometry at the University of California, Berkeley, said Joe was “stereo blind.”

Dr. Levi encouraged Joe to contact Sue Barry, a famous amblyopia patient who worked to overcome her condition and gain binocular vision. Dr. Barry, a neuroscientist in Massachusetts, was featured in The New Yorker magazine as well as on NPR.

Dr. Barry, like Joe, was born with a crossed eye. Working with optometrists, she was able to gain full stereo vision. Barry says that gaining stereo vision made her feel more a part of the world, “an incredible sense of being immersed in the space around you, as opposed to looking in on it from a slight distance away.” Now Joe is working to gain stereo vision, and teach his old brain new tricks.

Read and listen to the NPR Morning Edition story

Read Dr. Barry’s article: