Boring' reading and nearsightedness.

"Boring' reading and nearsightedness 

Glasses worn for nearsightedness are acommon sight among those who love to read, a studious relationship that has been attributed to everything from lack of eye exercise to improper diet. But nearsightedness may actually be a reflection of "nonstimulating' viewing that visually starves certain areas of the eye, say scientists at the City University of New York. They further suggest that the black-and-white page might do well with a splash of color.

"It's always been assumed that readingis related to myopia [nearsightedness caused by lengthening of the eyeball] because of the closeness of the page,' says project leader Josh Wallman. But he attributes at least some myopia to what he calls "the peculiarities of the page,' where the majority of characters are black and uniformly small. "Reading is a kind of mild deprivation of the retina, mainly because the cells away from the [center of the retina] cannot distinguish between the little characters of the typical printed page,' he told SCIENCE NEWS. The New York group tested the effects of visual deprivation on those areas of the retina other than the center, which sees images most clearly.

By covering the eyes of chicks withtranslucent "blinders' of different shapes, the scientists blocked visual images from being "seen' by part or all of the retina. The experiments induced local myopia-mimicking changes in the shape of the animals' eyes, which became enlarged only in the regions deprived of visual images. Previous laboratory experiments by other groups have focused on global, or overall, changes in the shape of the eye caused by image deprivation, the scientists report in the July 3 SCIENCE.

Why the changes are so localized isunknown, says Wallman. But the group currently is searching for diffusible chemicals that may be signals sent by the understimulated retina to the corresponding outside layers of the eye, subsequently encouraging the changes in eye shape.

Wallman and his coauthors say it islikely that further research will confirm several of the theories on myopia. Because many questions remain unanswered, identifying a possible chemical cause would offer no clear message on ways to prevent all myopia, says Wallman. However, he does suggest that revised page design, with large, colored forms scattered amid the black-and-white print, may stimulate broader areas on the retina.