Most eye exams and screening tests are built around the measurement or obtainment of 20/20 visual acuity. While important, visual acuity is only a small part of what “good” vision entails and does not measure how effectively or efficiently a person is using their vision. Deficiencies in the visual skills listed below are more often associated with learning problems and/or other functional vision problems and can be treated with vision therapy.
Ability to accurately track and follow with our eyes. Inaccurate tracking skills can cause loss of place when reading, skipping over words/lines, poor reading fluency, “careless” errors and difficulty with eye-hand activities including sports.
When we look far away, the focusing muscles in each eye relax, when we look up-close they constrict. The accurate and efficient use of these muscles allows us to focus on near-print for a sustained period of time and easily switch our focus from near to far and back again. Inefficient focusing skills may cause blurred vision, visual fatigue, trouble copying from the board, reduced reading comprehension and avoidance of near-point activities.
Ability of the eyes to work together as an efficient, coordinated team to create a clear and single picture when looking near or far. Small eye teaming problems cannot readily be detected by the untrained observer; however, they do significantly interfere with the ability to efficiently process visual information, especially at near when reading and writing. Deficiencies in eye teaming skills can cause numerous symptoms and adaptations including eyestrain, headaches, blurred or double vision, words run together when reading, difficulty with handwriting/spacing, covering or closing of an eye, decreased reading comprehension and most commonly in children, difficulty keeping attention on reading and writing tasks.
A more severe eye teaming problem can create difficulty with depth perception and understanding where we are in relation to other objects. Sometimes this is caused by a severe misalignment of the eyes that can easily be observed by a lay person or in photographs. Over time, these severe eye teaming problems can cause undesirable adaptations such as head turns/tilts, suppression of visual information from the turned eye or an amblyopia/lazy eye. While these adaptations reduce the confusion, poor eye alignment interferes with the ability to judge distances for driving and sports, creates difficulty with eye hand coordination, reduces depth perception and creates an overall inefficient visual system.
When eye movement, focusing or teaming skills are under-developed, it is often causes difficultly with understanding where we are in our visual space. The signals we get from our vestibular (inner ear), proprioceptive (our joints and muscles) and visual systems must be integrated in order for us to function well and have balance, and coordination. Vision is particularly important because it also answers the question of where we are in relation to the objects around us. It is very common for people with poor visual skills to “tunnel” their vision and have difficulty with peripheral awareness. This makes eye teaming and tracking more difficult. Vision therapy improves both the visual skills and spatial awareness, leading to better coordination and improved sensory integration.