Sideways Glance: Training helps people circumvent failing sight
By Nathan Seppa
People with the eye disease called age-related macular degeneration must often contend with a blank or fuzzy spot at the very focus of their vision. Researchers have now developed a rehabilitation regime that may enable many elderly people with the disease to get around this impediment.
Previous attempts at such vision retraining haven’t been standardized and properly tested, says Janet P. Szlyk, a psychophysicist at the University of Illinois at Chicago College of Medicine. These therapies may partially restore reading ability in some patients, Szlyk says, but there’s little evidence to suggest they improve other aspects of vision.
Many young people who have lost central vision gradually begin to take advantage of the vision that remains at the periphery of their gaze. Elderly people with macular degeneration do this with less success. Nevertheless, some scientists have attempted to identify areas of the retina, the light-sensing portion of the eye, that contain islands of visual acuity in elderly patients and then train these people to use the islands to see more clearly.
Szlyk and her team applied that approach to eight elderly patients experiencing a central blurry spot. The scientists administered a test in which letters and objects flash randomly in the vision’s periphery. The scientists created a profile of each patient’s acuity at 27 locations within the retina.
They then devised an 8-week course of eye exercises in which patients learn to look slightly away from an object of interest so that they’re using the areas of their retinas that work best. The rehabilitation first teaches patients to recognize simple symbols with their peripheral vision and progresses to more complex ones.
Most patients improved their vision significantly and increased their ability to “navigate in the real world,” Szlyk reported at a meeting sponsored by Research to Prevent Blindness last week in Washington, D.C.
“This is a very interesting scientific approach,” says Harold F. Spalter, an ophthalmologist at Columbia University. Szlyk and her colleagues “more rigorously pursued” a strategy for strengthening people’s peripheral vision than previous rehabilitation attempts have, says Spalter.
****************
If you have a comment on this article that you would like considered for publication in Science News, please send it to editors@sciencenews.org.
