In one study, three-fourths of the students in a Virginia literacy program failed a vision screening. The most common difficulty identified during the screening was an eye-tracking problem, which made it difficult for subjects to move their eyes smoothly along a line of print.
In the other study, two-thirds of the students in a literacy program in New York failed the vision screening. In this study, the most common difficulty was the inability to see clearly at a normal reading distance.
Just because your literacy-program students already wear glasses doesn't mean that they don't have undetected vision problems. Although most schools screen for these problems today, many older people in the work force may have received screening tests for distance vision only, according to Joel Zaba, OD, who headed the Virginia study. "Many in the adult illiterate population may not have had their learning-related visual problems detected earlier," he says.
The American Optometric Association lists the vision skills needed for good reading performance:
- Visual Acuity:
Visual acuity is the ability to see objects clearly. Reading letters on an eye chart only measures how well or poorly the person can see at that distance.
- Visual Fixation:
- Binocular Fusion:
- Field of Vision:
- Visual Perception:
Pursuit fixation is the ability to follow a moving object with the eyes, such as reading a sign on a moving bus.
Form perception is the ability to organize and recognize visual images as specific shapes. The shapes encountered are remembered, defined and recalled.
Individuals who present some of these visual problems may require nothing more than a pair of glasses before they can get the most out of a literacy program. Other problems require vision therapy to help the student learn to use both eyes together, develop eye-tracking skills or improve other skills needed for reading, says Andrea P. Thau, OD, who headed the New York study. Detection of these problems improves the chances of success of literacy efforts, but uncovering a cause for reading difficulties also has a positive effect on literacy students' motivation.
Further information on learning-related vision problems is available from:
American Optometric Association
243 N. Lindbergh Blvd.
St. Louis, MO 63141
A checklist of vision-related symptoms and single copies of a pamphlet, Do Vision Problems Cause Adult Reading Problems? are available. Send a self-addressed, stamped, business-size envelope with your request to the Communications Center at the above address.
Personnel Journal, November 1994, Vol. 73, No. 11, p. 50.