Department of Psychology
Master of Arts
Recent research suggests that some reading disabled children process visual information differently due to a transient system or magnocellular pathway deficit. In light of this hypothesis, the present study represents an investigation of the visual processing abilities of both good and poor readers using a new technique which taps several aspects of transient visual input by presenting brief masked targets with varying attentional demand. Sixteen subjects' reading capabilities were assessed by the Woodcock Reading Mastery Test-Revised. The subjects were classified as reading disabled if they had a two or more year lag in reading skill (n=7) or as non-reading disabled if they showed reading capabilities at or above their expected age level (n=9). Subjects performed on the Visual Attention Analyzer in order to assess their UFOV™ the area of the visual field in which information can be acquired in a brief glance without head or eye movements. The UFOV™ protocol involves subtest measures of processing speed, divided attention, and selective attention. The first subtest requires subjects to identify a target at varying durations. The second subtest requires identification of a central target simultaneously with localization of a peripheral target at eccentricities of 10, 20, or 30 degrees. The third subtest requires the same responses but adds visual distractors with the peripheral target. The reading disabled subjects required longer durations to achieve equivalent performance in both the divided and selective attention tasks. This group demonstrated a more drastic reduction in UFOV^M than did normal readers when distractors were added in task 3. Furthermore, reading disabled individuals processed information in the right vs left half of the visual field differently than did non-reading disabled children. The reading disabled subjects made more localization errors overall and missed a significantly higher proportion of targets presented in the right half of the visual field. Reading disabled individuals processed visual information more slowly, were more easily distracted, and made more localization errors than did normal readers resulting in a reduction of the UFOV™. This pattern of results fits within the framework of the transient system deficit hypothesis for reading disabled children. Therefore, such differences in processing between normal and disabled readers may be the result of a transient system deficit in visual processing in reading disabled children.
Edwards, Jerri, "The Useful Field of View of Reading Disabled Children" (1995). Masters Theses & Specialist Projects. Paper 908.