I Think I Can...: Brain Rewiring 
by Andrew Kerr
December 2008

Not long ago, scientists believed that the brain finished developing sometime after puberty. After puberty, all one had to look forward to was a steady downward spiral of mental deterioration. Although hair loss and bad skin seem to be inevitable with age, as this writer ruefully learns each day, this depressing view of the brain has happily been overturned. In fact, the brain is proving to be a far nimbler and more malleable thing than scientists even a few decades ago ever imagined with their brains.

Georgia Tech School of Psychology researchers Eric Schumacher, graduate student Keith Main, and researchers from the Georgia Tech/Emory Wallace H. Coulter Department of Biomedical Engineering and the Emory Eye Center have found that patients suffering from macular degeneration, wherein the center of one's field of vision is reduced to a blurry gray blob due to retinal damange, can effectively rewire their brains to at least partially compensate for this vision loss. Although in these instances the patients cannot see as well as they did before the onset of macular degeneration (that's because the fovea, an organ directly behind the retina, is the processor for our sharpest and best seeing, and with the retina out of play in front of it the compensated vision cannot be as sharp), there is still observable improvement.

The general concept of the brain rewiring itself is not new; we have all heard of the phenomenon, and most of us have read some spectacular news stories related to the subject (such as this one about rewiring playing a role in reviving a man from a 19-year long coma). But remarkable as such stories are, today's scientists are even more interested in whether this rewiring can be induced by behavioral changes as well.

For years scientists have been fairly confident that there is connection between behavior and brain-rewiring. For example, crossword puzzles have been found to stave off Alzheimer's disease; articles about this seem to pop up every few years.

The connection between behavior and brain-rewiring is of special significance in the School of Psychology study. The behavioral change that was requested of the patients in the study was that they deliberately attempt to focus with non-affected parts of the eye in order to compensate for the blurry gray spot where the macular degeneration had occurred. Confirmation that the brain was rewiring came when pictures of the patients' brains showed that the same parts of the brain stimulated by use of the central visual field "lit up" when patients with macular degeneration had become practiced at using other parts of the eye to compensate for the loss of that central visual field. In other word, they had trained new parts of the eye to stimulate the part of the brain normally dedicated only to the central part of a person's field of vision.

The Tin Man famously speculated on all the things he could achieve if he only had a brain. Thanks to recent research, we are finding out more and more what a fantastic value the brain actually is.

Some elements of this piece were cannibalized from this Georgia Tech press release, "Brain Reorganizes to Adjust for Loss of Vision."