Nearly 1 in 10 children in any given classroom struggle with a binocular vision problem. Because up to 80% of a child’s learning in school is through vision (or visual skills), this can cause serious problems
Adults have as much need for this type of vision care as children. The difference is that as adults, we've learned over the years to compensate for these problems so we can continue with our work. But then at the end of the day, our mental fatigue has us leaving work feeling like we've just finished a race
Therapeutic and developmental vision care is an expanded area of optometric practice focused on the visual system. Vision therapy is like physical therapy for the eyes. It improves visual function by training the brain to better control the eyes. It can also improve higher level brain skills such as visual processing. It is a highly effective non-surgical treatment for many common visual problems such as lazy eye, crossed eyes, double vision, convergence insufficiency and some reading and learning disabilities.
Unlike eyeglasses and contact lenses, which simply compensate for vision problems, or eye surgery that alters the anatomy of the eye or surrounding muscles, vision therapy aims to “teach” the visual system to correct itself; Thereby strengthening the visual system as a whole.
Visual skills are like other coordination (or motor) skills – once they are learned, the brain retains that ability. Hitting a ball, riding a bike, tying your shoes, and writing are examples of motor skills that once learned, are retained for long periods of time. Vision therapy is eye-brain therapy that strengthens existing visual skills and enables new visual skills to be used easily and efficiently thus, enhancing learning and life.
Who is Vision Therapy For?
Vision therapy is safe, drug free and effective not just for children, but also for adults! You may have heard of vision therapy as a treatment for children, but adults have as much need for this type of vision care as children. It's often effective for adults because they are motivated to see their visual abilities improve.
When someone has trouble using both of their eyes together or focusing for long periods of time, this isn't a problem that one simply grows out of. A child with a visual problem often will become an adult with a visual problem.
It is estimated that 1 in 10 children have a vision problem severe enough to affect their learning in school, yet a school vision screening has the potential to miss up to half of these problems. Our neuro-visual exams with our developmental optometrists will check all aspects of eye health, vision and visual skills.
How a Vision Problem Can Affect Your Life
For your children, if you feel they are not achieving their potential or you have noticed some of the visual symptoms discussed here manifesting themselves, they should be referred for a comprehensive eye exam. The reason being that many of these problems will not be detected during a vision screening or routine pediatric health evaluation, and a child may not always know how to communicate their struggles.
As an adult, you'll generally figure out a way to compensate for any visual problems so that you can continue doing your work. But, that may mean you come home from work extremely tired or feeling like you've just run a race when all you did was sit at a desk and computer. In either case, a developmental optometrist can give you the answers to questions you weren't even sure you were meant to be asking
Vision & Reading
Normally a combination of deficits, rather than just one, are at the root of a child's reading difficulties
Often vision related reading deficits are overlooked due to children not complaining about how they see, maybe they've passed a school vision screening which has given them an "OK" on their acuity. Visual acuity is the ability to see objects clearly. It is usually the only skill assessed in a school vision screening. The typical school eye chart is designed to be seen at 20 feet and measures how well or poorly the child sees at that distance. Reading requires the integration of a number of different vision skills: visual acuity, visual fixation, accommodation, binocular fusion, convergence, field of vision and form perception.
Signs of Vision-RelatedReading Problems
holds book or paper too close
frequent eye rubbing during reading or homework
loses place or rereads lines when reading, which often gets worse with time
omits or substitutes words
uses finger to read
homework is slow
reading comprehension decreases with time
slow reading speed
tilts or turns head
closes or covers one eye
squints or blinks during reading
red or watery eyes after reading
crossed or drifting eye
clumsy, poor depth perception
Symptoms of Vision-Related Reading Problems
headaches, worse later in the day
eyestrain, sore eyes
tired, burning or itchy eyes during reading
Treating Vision-Related Reading Problems
An optometrist will examine the above visual skills and determine how well the child is using them. When a vision problem is diagnosed, he or she can prescribe glasses, vision therapy or both.Vision therapy has proved quite effective in treating reading-related vision problems through individualized programs designed to help a child acquire or sharpen vision skills that are necessary for reading.
Because reading problems usually have multiple causes, treatment must often be multidisciplinary. Educators, psychologists, optometrists and other professionals must confer and work together to meet each child’s needs.The optometrist’s role is to help the child overcome the vision problems interfering with the ability to read. Once this is accomplished, the child is then more capable of responding to special education efforts aimed at treating the reading problem itself.
Vision & Dyslexia
Vision problems do not cause dyslexia
Dyslexia is a frequently overused term, and is often mistakenly thought of as reading or writing letters backwards. But the main problem with dyslexia is persistent difficulty with phonics – the ability to attach sounds to letters and blend the sounds into words. Decoding or phonemic awareness are also terms sometimes used to describe phonics ability. Most dyslexic individuals show difficulty with phonics and other aspects of language function. Dyslexia can also make it more difficult to remember sight words.
Having a Reading Problem Does Not Equal Dyslexia
All children with reading problems are not dyslexic. Vision problems can affect reading, but they do not cause phonics difficulty, which is the hallmark of language based dyslexia.
Vision problems can also make reading more difficult, causing problems with fluency, speed and comprehension. But vision problems do not cause dyslexia. Vision therapy is not intended to treat dyslexia, as is discussed in the American Optometric Association’s position paper on dyslexia and vision therapy. Children with actual language based dyslexia need intensive reading tutoring like the Wilson or Orton-Gillingham methods.
What Should I Do?
Children with reading problems need a thorough vision evaluation to determine whether there are any vision problems affecting their reading. Your developmental optometrist will conduct a thorough assessment of eye health and visual functions and communicate the results and recommendations with you. If it is a vision-related problem, we will discuss how our management plans can improve these deficiencies. If it is dyslexia or something else, we will make sure to refer you appropriately.
Vision & Learning
vision and learning are intertwined. experts say that roughly 80% of what a child learns in school is information that is presented visually.
Vision is a complex process that involves not only the eyes but the brain as well. Specific learning-related vision problems can be classified as one of three types. The first two types primarily affect visual input. The third primarily affects visual processing and integration. Most routine eye exams evaluate only the first of these categories of vision problems — those related to eye health and refractive errors. However, many optometrists who specialize in children’s vision problems and vision therapy offer exams to evaluate functional vision problems and perceptual vision problems that may affect learning.
Eye Health and Refractive Problems
These problems can affect the visual acuity in each eye as measured by an eye chart. Refractive errors include nearsightedness, farsightedness and astigmatism, but also include more subtle optical errors called higher-order aberrations. Eye health problems can also cause low vision or permanently decreased visual acuity that cannot be corrected by conventional eyeglasses, contact lenses or refractive surgery.
Functional Vision Problems
Functional vision refers to a variety of specific functions of the eye and the neurological control of these functions, such as eye teaming (binocularity), fine eye movements (important for efficient reading), and accommodation (focusing amplitude, accuracy and flexibility). Deficits of functional visual skills can cause blurred or double vision, eye strain and headaches that can affect learning. Convergence excess and insufficiency are two specific types of functional vision problems that affect the ability of the two eyes to stay accurately and comfortably aligned during reading.
Perceptual Vision Problems
Visual perception includes understanding what you see, identifying it, judging its importance and relating it to previously stored information in the brain. This means, for example, recognizing words that you have seen previously, and using the eyes and brain to form a mental picture of the words you see.
Symptoms of Learning-Related Vision Problems Include:
Headaches or eye strain
Blurred or double vision
Crossed eyes or eyes that appear to move independently of each other (strabismus)
Dislike or avoidance of reading and close work
Short attention span during visual tasks
Turning or tilting of head to use one eye only, or closing/covering one eye
Placing the head very close to the book or desk when reading or writing
Excessive blinking or rubbing of eyes
Losing place while reading, or using finger as a guide
Slow reading speed or poor reading comprehension
Difficulty remembering what was read
Omitting or repeating words, or confusing similar words
Persistent reversal of words or letters (after second grade)
Difficulty remembering, identifying or reproducing shapes
Poor eye-hand coordination
Evidence of developmental immaturity
The brain, not the eyes, processes the visual world, including things like symbols, pictures and distances
Symptoms of a Visual Processing Problem Include:
Weaknesses in these brain functions are called visual processing disorders or visual perceptual disorders. For example, if your child passes the vision test but doesn’t see the difference between a triangle and a square, the eyes aren’t the problem. The issue is the visual processing skills.
With most children, visual processing develops normally without any special attention or intervention. In some children however, the development of visual processing skills does not keep pace with their growth in other areas. This lag of development can lead to difficulty acquiring a sound foundation in reading, handwriting, and math skills in the early grades.
While there are ways to help kids compensate for those weaknesses, visual processing issues present lifelong challenges if not addressed. They are not considered a learning disability, however are farily common in kids who have learning issues. They also impact their ability to do ordinary things like sorting socks or playing a simple game of kickball. They can also lead to problems with socializing and self-esteem. Some kids may become frustrated and withdrawn.
What types of Visual Processing Problems Can Occur?
Visual discrimination issues: Difficulty seeing the difference between two similar letters, shapes or objects.
Figure-ground discrimination issues: Not being able to pull out a shape or character from its background
Sequencing Issues: Difficulty in being able to tell the order of symbols, words or images.
Visual-motor processing issues: difficulty in using feedback from the eyes to coordinate the movement of other parts of the body.
Long or short-term visual memory issues: Difficulty recalling what has been seen
Visual-spatial issues: Difficulty being able to tell where objects are in space
Visual closure issues: Difficulty identifying an object when only parts are visible.
Letter, number and symbol reversal issues: Switching or reversing letters or numbers when reading, writing or speaking.
Reversals of letters, numbers or words
Sloppy handwriting, poor spacing of letters, can't stay on a line
Difficulty copying from the board
Doesn't complete tests or written work
Poorly organized written work
Overwhelmed with crowded pages or worksheets
Difficulty with scantron answer sheets
Responds better verbally (especially with spelling words)
Poor fine or gross motor skills
Confusion of similar words when reading
Poor retention of visual material (sight words)
Poor attention during visual tasks
Better auditory learner
Stereo-Vision (3D Vision)
Not everyone sees the world the same
What Do You Mean by 3D Vision?
As humans we have two eyes which deliver two slightly different images to our brain. The brain then compiles these two images into one single 3-D reality. When the two images are combined by the brain we are able to see objects as more than just flat or long, instead we have three-dimensions – width, height, and depth. This type of viewing is called stereo-vision, deriving from the Greek root “stereos” which means firm or solid.
With stereovision there is a better understanding of objects and where they are in space as the brain compiles the two images from our eyes than we see with more precision and can attain more information just by looking. Unfortunately, not everyone’s brain can automatically fuse the two images, sometimes a slight misalignment of the eyes or a traumatic brain injury can make it difficult for the brain to make sense of the separate images from each eye.
This results in a loss or lack of stereovision. Some people are not even aware that they do not see the world in 3-D because their brain has never been able to compile the two images and instead relied only on one preferred eye for all its visual information. Although some individuals adjust to a life without stereovision and have developed a way of interpreting objects in space, they will still have a more difficult time with everyday activities such as throwing or catching a ball, driving a car, or stepping off a curb.
Vision & ADHD
ADHD is one of the most common mental disorders affecting children
The signs of ADD/ADHD and vision problems overlap. Children with vision problems can show poor attention with classroom work and homework. Teachers and parents will often notice children taking frequent breaks, avoiding reading or becoming fidgety as their eyes fatigue.
Vision Problems Do Not Cause ADHD
Vision problems do not cause ADHD, but they can be mistaken for ADHD. Vision issues should be ruled out in children where a diagnosis of ADD/ADHD is being considered.
Vision issues such as farsightedness, eye teaming and focusing problems can affect a child's ability to sustain attention during reading and desk work.
Research has shown that children with convergence insufficiency are more likely to have a diagnosis of ADHD and score higher on the Conners Test even when they don't have ADHD.
This chart compares the symptoms of ADD/ADHD with those of vision problems
Eye Teaming, Focusing & Tracking
visual skills beyond 20/20
Eye Teaming (Binocularity)
Eye teaming, or binocular vision, is a visual efficiency skill that allows both eyes to work together in a precise and coordinated way. Good eye teaming allows sustained, single, and comfortable vision, and is the basis for depth perception. We are continuously attempting to aim both eyes at objects during all visual activities. Each eye sends a separate, slightly different image to our brain’s visual cortex, where the images are combined (or fused) into a single image. If we can do this easily, we will have a stable, 3D view of the world. If we cannot do this easily, objects can appear double or move, creating a confusing uncomfortable view of the world. Eye teaming problems typically cause double vision, headaches, blurred vision and eyestrain, especially during reading and close work.
Most people are not aware that we have to refocus our eyes when we look from one place to another. This is because the focusing system usually operates so well that objects always appear in focus. However, in reality a focusing adjustment is made every time we look from one place to another. This adjustment is made with the help of a muscle called the ciliary muscle, or focusing muscle, which is located inside the eye.
For example, when a child looks from the board to their desk, they must contract or tighten this ciliary muscle. This causes the lens inside the eye to change shape and allows the child to see the print clearly. When the child looks back up from their desk to the board, they must now relax the focusing muscle to once again achieve clear distance vision.
A focusing problem occurs when an individual is unable to quickly and accurately relax or contract the focusing muscle, or if this muscle contraction cannot be maintained for adequate periods of time such as during reading or desk work.
Tracking (Saccades & Pursuits)
In order to use our vision efficiently, the eyes must move accurately, smoothly, and quickly from place to place. Eye movements allow accurate scanning of the visual environment for information. For example, every time a child looks from the board to their desk, the eyes must accurately jump from one target to another. The same is true for reading as the eyes jump from one word to another while scanning a line of print. Tracking is also important for following moving objects in sports, and for directing our eyes to move our hands towards a target. Eye-hand coordination in any activity starts with accurate eye movements.
Tracking skills are considered the fine motor aspect of vision. When a person has a tracking problem, eye movements are slow, inaccurate, or require head or finger movement to help the eyes track. This can interfere with reading fluency and comprehension, copying, handwriting, and sports performance.
Strabismus & Amblyopia
understanding the difference
This is a condition in which both eyes do not look at the same place at the same time. It occurs when an eye turns in, out, up or down and is usually caused by poor eye muscle control or a high amount of farsightedness. Normally, the eyes work together so they both point at the same place. When problems develop with eye movement control, an eye may turn in, out, up or down. The eye turning may be evident all the time or may appear only at certain times such as when the person is tired, ill, or has done a lot of reading or close work. In some cases, the same eye may turn each time, while in other cases, the eyes may alternate turning.
Strabismus usually develops in infants and young children, most often by age 3, but older children and adults can also develop the condition. There is a common misconception that a child with strabismus will outgrow the condition. However, strabismus may get worse without treatment. Any child older than four months whose eyes do not appear to be straight all the time should be examined.
Maintaining proper eye alignment is important to avoid seeing double, for good depth perception, and to prevent the development of poor vision in the turned eye. When the eyes are misaligned, the brain receives two different images. At first, this may create double vision and confusion, but over time the brain will learn to ignore the image from the turned eye (suppression). If the eye turning becomes constant and is not treated, it can lead to a condition called amblyopia or lazy eye.
Also called lazy eye, amblyopia is decreased vision that results from abnormal visual development in infancy and early childhood.
Amblyopia develops when nerve pathways between the brain and the eye aren’t properly stimulated. As a result, the brain favors one eye, usually due to poor vision in the other eye. Normally, the images sent by each eye to the brain are identical. When they differ too much, the brain learns to ignore the poor image sent by one eye and “sees” only with the good eye. The weaker eye tends to wander giving it the label “lazy”. Vision in the amblyopic eye may continue to decrease if left untreated and vision loss can range from mild to severe. Over time the brain simply pays less and less attention to the images sent by that eye. Eventually, the condition stabilizes and the eye becomes virtually unused.
Although amblyopia usually affects just one eye, it’s possible for both eyes to be affected. Sometimes this condition is not evident without an eye exam.If you notice your child’s eye wandering at any time beyond the first few weeks of life, consult your child’s doctor. Depending on the circumstances, your doctor may refer your child to a specialist in eye conditions. It is recommended all children have a complete eye exam between ages of 3 and 5. There is a long standing misconception that amblyopia cannot be treated beyond a certain age however, numerous recent studies have shown that this is not true.
Strabismus & Amblyopia
understanding the difference
Strabismus is classified by the direction the eye turns:
Inward turning is called esotropia
Outward turning is called exotropia
Upward turning is called hypertropia
Downward turning is called hypotropia
Other classifications of strabismus include:
The frequency with which it occurs, either constant or intermittent
Whether it always involves the same eye (unilateral)
If the turning eye is sometimes the right eye and other times the left eye (alternating)
Signs and symptoms of amblyopia include:
An eye that wanders inward or outward
Eyes that may not appear to work together
Poor depth perception
Vertigo and Dizziness
Don't live your life off balance
Like so many elements that make up the brain's systems, your visual system and vestibular (balance) system are designed to work with each other and be in balance. We like to use an analogy from The Vestibular Disorders Association which consists of a photographer and a camera. Imagine your vestibular systems is a photographer that is responsible for holding a camera steady in order to take a picture that isn't blurry. In that example, the 'camera' is your visual system.
Now consider you purchase a very expensive camera and then try to take family photos while balancing on one foot on shaky ground. In the same sense, even if your visual system is working well, without a properly functioning vestibular system, you will likely experience issues with focusing, unsteady objects or double vision.
Vestibulo-Ocular Reflex (VOR)
Throughout the course of the day and normal activities, your head and eyes are continually moving, the vestibulo-ocular reflex (VOR) is what keeps your perception of the world around you steady and stable. You can imagine that any disruptions in that system may lead to problems, but did you ever associate those with your vision? Here is an example of some common symptoms: