For the majority of eye care providers, vision care is limited to the treatment of ocular health concerns, and the compensatory management of vision conditions and disorders. Behavioral and developmental optometrists also support patients who are suffering with functional vision problems and visual information processing challenges. At Mind-Body-World Optometry, we understand that patients who have been diagnosed with dyslexia (or who are suspected of having dyslexia) may have learning-related vision problems which exacerbate or mimic the very same symptoms which an educator may diagnose as dyslexia. While Dr. Slotnick does not diagnose dyslexia, she is well-versed in identifying and treating vision problems that can directly impact the ability to learn, to read, and to comprehend the meaning represented by symbols and words on a printed page.
What is Dyslexia?
Dyslexia is a learning disability that affects how the brain processes written language. Difficulties with a child’s ability to learn the names or sounds of letters, challenges with accurate word recognition, and poor decoding abilities can all indicate the presence of dyslexia.
There is controversy within the literature about whether there is any visual component to dyslexia. This may be due to a lack of agreement on the definition of what constitutes “vision.” But a typical (sighted) school-age child is not expected to read with eyes closed! Reading requires visual skills: The first step is to bring your eyes to the symbols on the page. This entails eye movement control, focusing, and eyesight before any information processing interference is considered.
Visual Elements in the Reading Process
At a minimum, fluent reading requires single-and-clear vision. This means the two eyes must coordinate to aim in the same place, and must focus accurately enough to see the text clearly.*
*Children with a significant deficit of binocularity (like amblyopia or strabismus —lazy eye or eye turns, respectively) may employ alternative processing skills to avoid seeing double, even if the eyes do not coordinate well.
The minimum visual requirements for reading are:
- Accurate eye-teaming at near-point (single binocular vision).
- Accurate focusing (accommodation).
- Ability to perceive several characters at a time (visual field “span”).
- Ability to direct the eyes in sequence across a line of text with accurate line-returns (oculomotor control).
- Visual discrimination skills (perceptual identification and discernment between similar forms). This generally refers to the ability to pick up details (such as the differences between similar letters, like ‘c’ and ‘o’). It also may include the ability to recognize differences in orientation (such as differentiating among ‘b’, ‘d’, ‘p’, and ‘q’).
Any child who is suspected of having dyslexia deserves a functional vision evaluation to identify or rule out the vision problems which interfere with the ability to read, to learn, and to comprehend visually-presented reading material. The basic visual input skills can be readily remediated, setting the stage for the reading process.
How Vision Problems Impact Reading and Learning
The visual abilities can be separated into two major categories: Visual Input Skills and Visual Information Processing Skills.
Visual input skills are all of the aspects of bringing visual information from our environment into our brains. This includes the physical ability to coordinate the eyes for single vision, to bring the eyes into clear focus, to control and direct where the eyes aim, and to have a wide enough visual field to be able to select the next area for visual attention.
Visual information processing skills are all of the aspects of converting visual input into meaning. Once the visual information has been gathered, what do we do with it, in the brain, to derive meaning? And how do we use this information to direct action? In this way, visual information processing skills may be considered as the visual output skills.
While we may describe these aspects of the visual process in separate categories, in practice, we are utilizing visual input skills and visual processing skills in a coordinated concert of activity.
Reading vs Decoding
Fluent readers are not merely efficient at decoding symbols and naming words printed on a page. They transfer printed symbols into thoughts, concepts and ideas. They process whole phrases, clauses, sentences and paragraphs directly into meaning. Decoding the printed words is only the beginning of the reading process. Experienced readers immediately associate words and phrases with meaning, and they often visualize images and interactions as they read. When asked about what they have read, they retain these images and concepts, rather than the specific words that were used to generate the thoughts. Experienced readers only rely upon decoding skills when they encounter unfamiliar words.
Visual Problems which can mimic or exacerbate Dyslexia
Vision problems, including those related to dyslexia, can affect an individual's ability to read, learn, and comprehend in several ways:
• Focusing problems (Accommodative infacility or insufficiency): As the print gets smaller, some children may experience blurring of letters if they are not accurately focusing on the page. Children who have moderate to high amounts of farsightedness (hyperopia) may avoid reading for more than a few minutes at a time if they have difficulty focusing accurately on the print. They can see clearly, but they may not be able to sustain clear vision for efficient reading or school work.
• Convergence Insufficiency: If an individual has difficulty coordinating both eyes to work together, discomfort or even double vision may occur. This can interfere with accurate eye-tracking, and may cause distractibility or avoidance when reading.
• Eye Tracking Problems: Poor eye movement control can make it challenging to read fluently or make accurate line-returns without re-reading or skipping lines. Eye tracking problems which may impact reading include oculomotor dysfunction, and deficits of saccadic eye movements. However, the underlying challenges often include a constricted use of the visual field, resulting in inaccurate direction of the eyes over an area of text.
• Visual Discrimination deficits: The ability to discern letters of similar shapes. It is necessary to have sufficient visual acuity to be able to distinguish and recognize symbols with minimal effort. Early on, the potential impact of uncompensated refractive error or poor focusing accuracy may be missed, since children’s books typically have large print. As print gets smaller in school-age years, the impact of refractive state (generally referred to as “refractive error”) and visual input skills starts to appear as a lack of progress in reading competency, fluency and comprehension between 2nd and 4th grade.
• Visual Spatial Processing deficits: What happens when the same symbol is used for multiple letters, such as b, d, p and q? For patients with reading delays, much of the challenge is in visual information processing and spatial organization. As a child differentiates the left and right sides of the body (laterality) and the direction of writing, eye-tracking, and movement in space relative to their own body frame (directionality), the differentiation of ‘b’ from ‘d’ and ‘p’ from ‘q’ becomes more automatic. However, for children who struggle to develop body organization skills, their left-right differentiation is delayed, and they resort to making educated guesses for the words containing b’s and d’s, or lose fluency as they try to decode these confusable symbols.
• Visual Sequential Processing deficits: A common misconception is that people with dyslexia may try to read the symbols out-of-order. For these patients, it may appear as though text is shifting over the page. This perception is often due to challenges in binocular alignment (such as convergence insufficiency). Difficulty maintaining one’s place due to eye-tracking deficits can also give the appearance of text being perceived out-of-order.
Some individuals struggle to parse small details in a crowded visual area. They may grab the first and last letter-or-two of a word, and fill in the middle with approximations and guesses based on context clues. The detailed sequencing of letters within the words can be elusive for children with reading challenges, and may result in spelling challenges and creative spelling on writing assignments.
• Visual Stress: When an individual is struggling, whether this struggle is physical or perceptual, they may experience visual stress. The additional strain on the eyes can make reading feel difficult, or even painful. When the visual system is under stress, this may lead to a cascade of challenges, including:
- Large pupils, which can lead to higher focusing demands.
- Accommodative infacility or insufficiency: reduced focusing control during periods of overwhelm.
- Constricted functional visual fields: Under stress, the visual system will take in smaller parcels of information. This in turn interferes with both eye-tracking skills and eye-teaming skills!
Benefits of Vision Therapy for Children who may have Dyslexia
Fortunately, learning-related vision problems can be treated! Many children with a diagnosable learning-related vision problem are often diagnosed with or suspected of having dyslexia as well. There are several notable benefits of optometric vision therapy for these children:
• Accommodation Training: Learning to switch between different visual distances can help reduce visual strain and fatigue.
• Tracking and Coordination: Enhanced eye tracking and binocular coordination make it easier to read with accuracy and fluency.
• Stress Reduction: Reducing visual stress can lessen the strain on the eyes, making reading and focusing more comfortable and enjoyable. It also enhances the available visual field, which supports accurate eye-tracking from line to line.
• Visual Processing Enhancement: Engaging in rhythmic visual processing activities prepares children for fluent, meaningful reading. During a therapy program, activities which develop “Rapid Automatized Naming” (RAN) skills help children to grab several small visual components and learn to keep them in sequence. Creative activities promote fluency with a variety of symbols (i.e., not just using letters and numbers), which trains the brain to improve sound-symbol recognition (RAN) during visual-motor planning and oculomotor control exercises. Improving the underlying visual processing skills aids in the recognition of words, letters, and patterns. This translates into the development of improved tachistoscopic (quick-seeing) visual memory and the ability to recognize words at a glance. This in turn enhances the amount of energy available for processing information and ideas, all while keeping the eyes automatically on-track.
Contact Mind-Body-World Optometry in Scarsdale, NY
If your child has been diagnosed with dyslexia, or if you believe your child exhibits the signs and symptoms of the condition, working with an optometrist or eye doctor who specializes in learning-related vision problems is essential. At Mind-Body-World Optometry, Dr. Slotnick will work with you to determine the best form of eye care or vision therapy suited to your needs. If you live in Scarsdale, NY, and are looking for an optometrist near you, contact Dr. Slotnick at Mind-Body-World Optometry to schedule your consultation today. We are dedicated to providing the specialized care you need to improve your visual health and overall well-being.