By Dr. Paul J. Lederer
A significant number of children (20%-25%) in our classrooms are suffering from undiagnosed visual problems. These visual skill deficiencies can reflect in both performance deficits and behavioral adaptations. The more parents, teachers, and related professionals become aware of symptoms which typify these visual problems, the better we are able to identify those children who are at risk.
It is important to differentiate the measure of sight from the complex process of vision. Sight is the simple response of the eyes to light and to the differences in brightness contrasts. Vision is a sensory-motor-perceptual process. It is the ability to identify, interpret and understand what is seen. Vision is learned and constantly undergoes change and development. Many of these children with learning related visual problems have 20/20 distance eyesight but cannot sustain prolonged near visual work without visual stress or avoidance.
Following are definitions of the primary physiological skills required to perform efficiently along with a checklist of symptoms which typify deficiencies in these visual skills.
1. Eye Movement Skills (tracking) – the ability to move the eyes smoothly, accurately and effortlessly in tandem whether following a line of print in a book or the flight of a ball through the air.
- head turns as reads across page
- loses place often during reading
- needs finger or marker to keep place
- too frequently omits small words
- displays short attention span in reading or copying
- writes up or downhill on paper
- rereads or skips lines unknowingly
2. Focusing Skills (accommodation) – the ability to look quickly from far to near and vice versa without momentary blur (e.g. looking from the chalkboard to the book). This skill involves the clearing of an image for identification.
- tires easily
- blinks to make the chalkboard clear up after desk work
- rubs or blinks eyes during or after short periods of visual activity
- makes errors in copying from chalkboard to paper or desk, or from
- reference book to notebook
- avoids near centered visual tasks
- comprehension reduces as reading is continued
- loses interest too quickly
3. Eye Teaming Skills (Binocularity) – the ability to use both eyes together smoothly, equally, simultaneously, and accurately. All judgements of spatial localization, depth perception and the accuracy of a single clear image depend upon this paired action of the eyes.
- squints, closes or covers one eye
- extreme head tilt while working at desk
- complains of seeing double (diplopia)
- omits letters, numbers or phrases
- repeats letters within words
- misaligns digits in number columns
4. Eye-Hand Coordination Skills (visual motor integration) – This ability is dependent upon the use, practice and integration of the eyes and the hands as paired learning tools. With this skill comes more effective ability to make visual discrimination of size, shape, texture and location of objects.
- writes crookedly, poorly spaced; cannot stay on ruled lines
- uses finger or hand to keep place on the page
- must feel things to assist in any interpretation required
- uses other hand as a “spacer” to control spacing or alignment on thepage
- eyes not used to “steer” head movements
- extreme lack of orientation in placement of words or drawing on the page
- Other aspects of visual perceptual development involve learning readiness skills such as:
- concepts of laterality and directionality (right-left awareness),
- visual memory and visualization,
- visual closure,
- figure ground discrimination.
Classically, deficiencies in these skill areas reflect more in aspects of learning how to read. Many children, however, show no difficulties in these aspects of visual perceptual development but, nevertheless, are lacking in the visual skills of focusing, eye teaming, and tracking. Visual skill difficulties are more apt to surface during the sustained academic demands of reading to learn.
Adaptations to visual problems vary widely. Some symptoms of visual stress can be difficult to observe. Some individuals avoid sustained visual activities. Others, who are highly motivated, may work unnecessarily hard to compensate for the burden of visual inefficiency. The child will not outgrow these visual problems, but rather must adapt. Behavioral avoidance responses often develop to mask expected failure, self esteem is reduced and true performance potential is distorted.
Visual examinations which only evaluate sight and health are not adequate enough to rule out these types of visual skill deficiencies. Therefore, it is essential that visual skills are evaluated at the near working distances. If visual skill deficiencies are diagnosed, a remediation program (vision therapy) is essential to alleviate these skill deficits and the related visual stress symptomatology. A vision report should be sent to the school and related professionals to support a team oriented approach to the student’s performance and/or behavioral difficulties.
The American Optometric Association has stated that, based on extensive research, vision therapy is effective in the treatment of physiological, neuromuscular and perceptual dysfunctions of the vision system.
Please note that:
in no way is this treatment involved in teaching reading, but rather in improving the visual skills required to perform at this task efficiently;
early diagnosis and treatment is essential if secondary behavioral adaptations and/or related educational lags are to be avoided;
being bright does not mean you can’t have a visual problem, it only means you must apply more effort to compensate for these inefficiencies;
our best combatant against the large numbers of undiagnosed children with visual skill difficulties is good observation by parents, teachers and related professionals, and annual vision examinations which go beyond the “looking glass”.