Week of January 25, 1999The show begins with a visit to the office of Karen Gourgey, director of the Computer Center for Visually Impaired People at Baruch College in New York City. Ms. Gourgey, who has been blind since birth, demonstrates how talking computers, old-fashioned braille typewriters and her seeing eye dog all help her navigate a world designed for sighted people. She shares her reflections on what it might be like to be sighted -- they may surprise you.
For more information about the resources her center provides, you can write The Computer Center For Visually Impaired People, Division of Continuing Studies, Baruch College, 151 East 25th Street, New York, New York, 10010. You can also call the center at 212-802-2140; or visit the Center's Web site.
Next, Dr. Goodwin speaks with Nobel Prize-winning vision researcher Dr. David Hubel, of Harvard Medical School. He explains how the first three stages of visual processing begin in the eyes, at the retina, but then much more of our brain -- about a quarter of it in fact -- gets involved.
Each eye actually has about a million nerve fibers connected to the brain, and these fibers ultimately go to 'visual area one', a credit-card sized area at the back of the brain. The 'input' from each eye is slightly different, and it is these differences that give you depth perception -- a discovery made in 1830.
Dr. Goodwin takes a call from Donna in Los Angeles asking about differences in color perception from one eye to another. Dr. Hubel says a few factors could be involved. The difference could be in the lens of the eye. When older people have their cataracts removed, for example, they see blues as deeper and richer because their lenses had yellowed with age. There could also be a difference in the receptor cells of the eyes which take in light.
Dr. Goodwin asks about color perception in general. Does color exist in the outside world or in our brain?
Dr. Hubel responds that experiments show it is mostly a matter of what is going on in our own brains, or nervous systems. He takes a call from Kevin, who asks if there are differences in the visual cortices of people who are blind from birth, versus people who become blind, versus people who are sighted.
It turns out that animal experiments and observation of humans have shown that there is a 'critical period' when the visual cortex is developing, early on in the life of the person or animal. If vision is interfered with during this period, there are permanent effects on the brain. Dr. Hubel's work on developmental issues actually led to advances in the treatment of people who are cross-eyed, showing that surgery to correct such problems must be performed early-on.
Dr. Hubel and Dr. Goodwin finish their conversation by talking about eye movement. It's not commonly known that the eye is actually moving all the time, every second, involuntarily, even when one's eye is fixed on one spot. If the eye is immobilized, the image fades away. Essentially the eye is constantly refreshing its input but the brain processes these signals into a single visual image.
The doctors also discuss how important more basic research on the mechanics of vision is for finding ways to treat visual impairments. Dr. Goodwin points out that nearly 50% of successful clinical outcomes result from basic research that is actually unrelated to the ultimate treatments. In other words, science is full of surprises.
You can reach Dr. Hubel care of Harvard Medical School, 220 Longwood Avenue, Boston, MA, 02115. His book "Eye, Brain, and Vision," is a part of the Scientific American library. Click here for more information or to order his book.Then, reporter Bud Lowell explores an unusual method of vision therapy, designed to help classical musicians improve their performance. It involves bouncing on rubber balls, matching one's eye movements to a metronome, and more. Behavioral optometrist Ray Gottlieb and musician Rebecca Penneys demonstrate these techniques and explain how they can help coordinate vision and attention. You may send e-mail to Dr. Gottlieb or Ms. Penneys, an instructor at the Eastman School of Music. rapy@uhuru.cc.rochester.edu, or find out more about behavioral optometry at their Web site: www.covd.org.
The new film At First Sight starring Val Kilmer and Mira Sorvino is another in the growing number of movies adapted from the case studies of best-selling author Dr. Oliver Sacks. The author of The Man Who Mistook His Wife for a Hat, Awakenings, and, most recently, The Island of the Colorblind speaks with Dr. Goodwin about Virgil, blind since early childhood, who recovered most of his sight as an adult.
Dr. Sacks explains that Virgil, played by Val Kilmer in the film, is one of only 25 to 30 such cases reported in medical literature since the 17th century. Virgil's restored sight was a mixed blessing for him. The impact of this new sense was overwhelming, and though he saw movement, color, and boundaries, he couldn't recognize shapes or judge size and distance. Naturally he had a strong tactile sense with which he had been navigating the world. Again, important parts of the brain involved in vision develop with use, not automatically.
Dr. Sacks also talks with Dr. Goodwin about what it's like to see his work adapted by others and watching famous actors learn their roles by studying his patients. And they discuss his recent case studies on colorblindness, for which he visited a small island in the Pacific where people lack cones on their eyes and are thus unable to see color.
Dr. Sacks is a professor of neurology at the Albert Einstein College of Medicine in the Bronx, NY. You may also read more about An Anthropologist on Mars, which contains Virgil's story, or The Island of the Colorblind.
Finally, commentator John Hockenberry on vision--and the difficulties of artificial intelligence.
And this week -- a public service announcement for "New Eyes for the Needy" featuring the one and only Joe Franklin. If you want to contribute your used glasses to the needy, write to: New Eyes for the Needy, Short Hills, NJ 07078.
