ABSTRACT
One of the principal explanations that has been used to explain reading disability has been the notion of a "perceptual deficit." This notion suggests that disabled readers suffer from an inability to perceive the world, and particularly alphabetic material, the way normal readers do. A perceptual deficit is often considered to be a relatively low-level problem compared with cognition and comprehension. Typically, studies in support of a perceptual deficit explanation show that poor readers do not perform as well as good readers on discrimination tasks. A large experimental and clinical literature developed to support this notion. Yet, as Larsen and Hamrnill (I 975) indicate, "the educational usefulness of this important theoretical construct has never been fully substantiated, (p. 282)." Indeed, recent work has suggested that neither good nor poor readers have trouble with discriminating letters (Lahey & McNees, 1975). This, of course,
raises the possibility that although reading disability and visual discrimination indeed may be correlated, there is no causal relationship. This becomes particularly important when we realize that many children are diagnosed as reading disabled based on tests of visual perception, for example, the Bender Visual Motor Gestalt Test (Bender, 1957). Zach and Kaufman (1972) examined childrens' scores on the Bender and compared these with their ability to perform discrimination tasks using the same forms. They found it was possible for a child to discriminate forms well and still obtain a score on the Bender that indicated a "perceptual difficulty." In examining the relationship of visual perceptual skills and academic achievement, Larsen and Hammill concluded that visual perception skills are not essential to academic achievement and that children who fail in school do so for reasons other than visual perceptual deficits.
