When children have trouble reading, it is imperative that parents and teachers investigate the many possible causes. Reading difficulty usually stems from a combination of problems, rather than just one. The difficulty in this is that children often do not present as though they have a vision problem. That is, they perform normally and appear to “see” like their siblings or classmates. It seems evident because these children appear to be able to function visually, they do not complain about their eyes and they often pass vision screenings at school. Reading however, requires the integration of a number of vision skills: visual acuity, visual fixation, accommodation, binocular fusion, convergence, field of vision, and form perception. The typical school screening eye charts only evaluate distance and near visual acuity so it is easy to miss the symptoms of reading-related vision problems. The following list of visual skills should be evaluated to determine the best approach to help a student become an accomplished reader.
Visual Acuity is the ability to see objects clearly. The typical eyechart is designed to be seen at 20 feet and measures how well or poorly the child sees at that distance. Near visual acuity may be different than distance and must be measured as well. This is typically performed at 12-16 inches.
Visual Fixation. Fixation is the ability to aim the eyes accurately. Static fixation is the ability to focus on a stationary object when reading a word or working a math problem. Saccadic fixation is the ability to move the eyes quickly and accurately across a page to read a line of print. Pursuit fixation is the ability to follow a moving object with the eyes. These complex operations require split-second timing for the brain to process the information received and to track the path of the moving object.
Accommodation. Accommodation is the ability to adjust the focus of the eyes as the distance between the individual and the object changes. Children frequently use this vision skill in the classroom as they shift their attention (and focus) between their book and the board for sustained periods. Being able to maintain focus at near distances is important for reading, writing and taking tests.
Binocular Fusion. Binocular fusion refers to the brain’s ability to gather information received from each eye separately and form a single, unified image. If a child’s eyes are not precisely aligned, he or she may experience blurred or double vision, discomfort, confusion or avoidance. If that occurs, the brain often subconsciously suppresses the vision in one eye to avoid confusion. That eye may then develop poor visual acuity. This condition is called amblyopia or lazy eye.
Convergence. Convergence is the ability to turn the two eyes toward each other to look at a close object. Children depend on this vision skill for reading and school deskwork. Without convergence, a child cannot accommodate well.
Field of Vision. Field of vision is the wide area over which vision is possible. It is important that a child be aware of objects in the periphery (left and right sides and up and down) as well as in the center of the field of vision. Near central (or para-central) vision is important for reading ability.
Perception. Visual perception is the total process responsible for the reception and understanding of what is seen. Form perception is the ability to organize and recognize visual images as specific shapes. The shapes the child encounters are remembered, defined and recalled when he or she begins developing reading skills.
To ensure your child has the potential to read at the most efficient level, we encourage a yearly comprehensive vision and eye health exam starting at age three. Exams for three year olds are complimentary at Cockrell Eyecare Center through a program call SEE to LEARN. Contact us in Stillwater at 405-372-1715 to schedule your child’s exam today. We also invite you to visit our website at www.cockrelleyecare.com and like us on Facebook at Cockrell Eyecare Center!