Controversy surrounds the debate on the impact of vision and visual functioning on academic performance, especially in the area of reading ability. Factions of the medical community dispute research findings and discount the necessity of healthy eye functioning as a factor in achievement. However, a plethora of scientific studies support the relationship between vision deficiencies and poor school performance. This literature review compiles the findings of many years of research to describe common visual deficiencies, to validate their impact on academics and reading, as well as provide recommendations for educators working with students exhibiting characteristics of vision problems.
...view middle of the document...
Convergence insufficiency (CI), another anomaly of binocular vision, lacks any visible characteristics. Jenkins (1999) defines this condition as the eyes’ inability to obtain or maintain adequate binocular fusion without extreme effort. Research suggests that approximately 3% to 7.7% of the population has convergence insufficiency (Bartuccio, 2009).
Symptoms of CI include eye fatigue, blurry vision, the blending of letters and words, double vision, nausea and headaches. Often these characteristics appear or become more evident during prolonged near-point tasks (Granet, Gomi, Ventura, & Miller-Scholte, 2005). Children with CI often squint, close or cover one eye during near tasks, tilt or turn their head abnormally, lack depth perception and express confusion about visual input (Rouse & Ryan, 1984).
Accommodative vision refers to the eyes’ capacity to maintain focus on a near target. Thus, accommodative insufficiency (AI) denotes the eyes’ inability to increase the optical power necessary to sustain a clear image when viewing something in close proximity, at the child’s developmental level (Shin, Park, & Park, 2009; Bartuccio, 2008).
Bartuccio (2008) noted that AI patients frequently report symptoms of blurring, headache, eye fatigue and double vision; less common symptoms include floating text, loss of comprehension while reading, and a pulling sensation around the eyes. This study also reported that some patients, as well as children under the age of 7.5 years old, experience no symptoms. More observable characteristics include teary eyes, holding reading materials too closely, frequent eye rubbing, red eyes and fatigue at the end of the day (Rouse & Ryan, 1984).
Oculomotor vision relates to the eyes’ movement while tracking text. “When reading, the eyes do not move smoothly but in a series of very quick jumps (saccades) in order to fixate successive stable images” (Singleton & Henderson, 2006, p. 90). Reading involves a series of mainly forward eye movements with limited regressions, or backward glances. Children with poor oculomotor vision may have difficulty fixating on a target, maintaining that fixation or unable to change visual fixation from one target to another.
These students may frequently lose their place, reread lines unknowingly, skip lines, omit words when reading or copying and lack comprehension after reading. To compensate for their impaired tracking ability, these children often use their fingers and move their heads excessively while reading (Rouse & Ryan, 1984).
Rouse & Ryan (1984) assert that students with visual skills deficits can benefit from many classroom accommodations. Minimizing time devoted to near-point tasks and copying from the chalkboard help. Teachers should also encourage these students to use their finger or bookmark and take frequent breaks while reading. For students with oculomotor deficits, teachers should avoid using texts with small print and urge their student to use eye contact with...