Visual symptoms and reading performance.

Clinical observation indicates that visual asthenopic symptoms are frequently associated with reading for long periods of time. We investigated the relation between visual symptoms and standard measures of reading performance in 78 university students. The number of asthenopic complaints increased during the reading phase of the experiment and decreased during the relaxation phase. Overall, a weak but significant negative correlation was found between number of symptoms and reading rate on the Nelson-Denny reading test. The most symptomatic subjects scored lower on vocabulary and comprehension than the least asthenopic subjects. A limited retrospective analysis revealed no reading performance differences between subjects having normal binocular vision and those showing a minimum binocular dysfunction; however, the dysfunctional subjects reported more visual symptoms. This study suggests that visual symptoms are a factor in reducing reading performance, particularly in very symptomatic individuals.