From Research to Prevent Blindness (RPB)…
By doing a set of vigorous visual exercises on a computer every day for several months, patients who had gone partially blind as a result of a stroke regained some vision. Some could drive again. "This is a type of brain damage that clinicians and scientists have long believed you simply can't recover from. It's devastating, and patients are usually sent home to somehow deal with it the best they can," said the RPB researcher.
"Rigorous Visual Training Teaches the Brain to See Again After Stroke". This article includes video of the process and the test.
"Perceptual relearning of complex visual motion after V1 damage in humans" by Huxlin KR, Martin T, Kelly K, Riley M, Friedman DI, Burgin WS, Hayhoe M., Abstract, Journal of Neuroscience. 2009 Apr 1;29(13):3981-91. doi: 10.1523/JNEUROSCI.4882-08.2009.
The full-text archive of this article from the U.S. National Institutes of Health's National Library of Medicine (NIH/NLM).