A new study from the University of Waterloo revealed that binocular vision problems, not always tested during a routine eye exam, may be to blame for some children’s reading difficulties, even when their vision is otherwise fine. Reading requires the eyes to work together, and that’s different from simply whether or not the eyes can see clearly.
Researchers explained that kids could have difficulty turning their eyes in or focusing on the words, leading to eye strain or double vision. Not only does this make reading difficult for kids, but their lack of success can discourage children from trying to read. Parents and educators need to rule out or address all vision issues when creating learning plans for children reading below their grade level.
What Is Binocular Vision?
As noted, binocular vision involves both eyes working together. This creates both depth perception and registers two independent images (one from each eye) as one in the brain, known as stereopsis. It requires both eyes “aim” at the same target.
Five facets of binocular vision exist:
- Tracking: eyes can follow or move where directed, like across a page while reading.
- Fusion: eyes work together as a team.
- Stereopsis: depth perception turning the images from both eyes into one 3-D view.
- Convergence: eyes move together, such as turning eyes in and out.
- Visual Motor Integration: coordination of visual perception with motor control, so the ability to use what the eyes see to direct the body, such as copying letters.
The symptoms of binocular vision problems can seem benign or are masked by other problems. Eye doctors group issues into three categories, accommodative, vergent and oculomotor.
- Accommodative issues involve stereopsis, such as focusing from one distance to another.
- Vergent issues involve tracking and convergence, or anything to do with eye movement.
- Oculomotor issues involve fusion and tracking, where kids lose their place while reading. Visual Motor Integration is an issue when responding to reading because of incorrectly perceiving what’s being seen.
You may already be familiar with the more common names for certain binocular vision problems. "Crossed eyes", "lazy eye" or "wandering eye", and "double vision" are all part of binocular vision issues, although there are more depending on which of the five facets is involved.
Symptoms Of Binocular Vision Problems
While some symptoms are easy to notice, others may only be obvious secondarily or with the examination. They include:
- poor hand-eye coordination
- double vision
- “lazy” or “wandering” eye
- trouble focusing on objects
- trouble following a page or losing your place while reading
- eye strain or fatigue
- closing one eye to focus
- tripping or bumping into things, “clumsiness”
If your child is having difficulty reading or any of the other symptoms listed above, it is imperative you make an appointment with your children’s eye doctor. Optometrists are trained to determine vision issues that can’t be observed by parents.
Treatment of Binocular Vision Issues
Often children who have difficulty reading receive Individual Education Plans that don’t address the vision issues they are experiencing. Having vision issues determined by a profession children’s eye doctor can put you on the proper course for resolving the problem and improving your children’s reading and overall academic success.
In some cases, eye muscle surgery is recommended although it is not always permanently effective, and in some cases, vision therapy can help. Vision Therapy involves exercises akin to physical therapy such as following a dot or line (or your finger!), practicing focusing on beads threaded through a string and moved toward and away from your eye (the string is tied to a doorknob, for instance).
If you have any concerns about binocular vision issues, talk to your optometrist. The problems don’t have to be permanent. And remember, children aged eighteen and under have their eye exams covered by Alberta Health so bring them in if there are any concerns.
Contact Us
If your child is experiencing difficulty in school and you think vision problems may be a contributing factor, schedule an eye exam and make sure to tell the eye doctor what your concerns are in case binocular vision needs further testing. Call our friendly kid’s optometrist at 403-280-7518 or use our online form.
