Author: Sarbind Kumar Yadav
Dyslexia is a specific learning disability that is neurological in origin. It is characterized by difficulties with accurate and/or fluent word recognition and by poor spelling and decoding abilities. These difficulties typically result from a deficit in the phonological component of language that is often unexpected in relation to other cognitive abilities and the provision of effective classroom instruction. Secondary consequences may include problems in reading comprehension and reduced reading experience that can impede the growth of vocabulary and background knowledge.
Therefore, dyslexia is a specific learning disability that appears to be based upon the brain and its functioning. It appears that dyslexia runs in families.
Individuals with dyslexia have difficulty with processing and manipulating the sounds in a spoken language. This is related to the ability to read words accurately and fluently. Individuals with dyslexia will also have difficulty with spelling. Some of the consequences of not reading accurately or fluently and thus having fewer reading experiences may include problems with reading comprehension and vocabulary.
Individuals with dyslexia have trouble with reading, writing, spelling and/or math even though they have the ability and have had opportunities to learn. Individuals with dyslexia can learn, but they often need specialized instruction to overcome the problem. Often these individuals, who have talented and productive minds, are said to have a language-based learning difference.
What causes dyslexia?
The exact causes of dyslexia are still not completely clear, but anatomical and brain imagery studies show differences in the way the brain of a person with dyslexia develops and functions. Moreover, most people with dyslexia have been found to have problems with identifying the separate speech sounds within a word and/or learning how letters represent those sounds, a key factor in their reading difficulties. Dyslexia is not due to either lack of intelligence or desire to learn; with appropriate teaching methods, students with dyslexia can learn successfully.
Dyslexia occurs in people of all backgrounds and intellectual levels. People with dyslexia can be very bright. They are often capable or even gifted in areas such as art, computer science, design, drama, electronics, math, mechanics, music, physics, sales, and sports. In addition, dyslexia runs in families; having a parent or sibling with dyslexia increases the probability that you will also have dyslexia. For some people, their dyslexia is identified early in their lives, but for others, their dyslexia goes unidentified until they get older.
Signs and symptoms of dyslexia
It is crucial to be able to recognize the signs of symptoms of dyslexia. The earlier a child is evaluated, the sooner he or she can obtain the appropriate instruction and accommodations he or she needs to succeed in school.
General problems experienced by people with dyslexia include the following:
- Learning to speak
- Learning letters and their sounds
- Organizing written and spoken language
- Memorizing number facts
- Reading quickly enough to comprehend
- Keeping up with and comprehending longer reading assignments
- Spelling
- Learning a foreign language
- Correctly doing math operations
Some specific signs for elementary-aged children may include:
- Difficulty with remembering simple sequences such as counting to 20, naming the days of the week, or reciting the alphabet
- Difficulty understanding the rhyming of words, such as knowing that fat rhymes with cat
- Trouble recognizing words that begin with the same sound (for example, that bird, baby”, and big all start with b)
- Pronunciation difficulties
- Trouble easily clapping hands to the rhythm of a song
- Difficulty with word retrieval (frequently uses words like “stuff” and “that thing” rather than specific words to name objects)
- Trouble remembering names of places and people
- Difficulty remembering spoken directions
It is important to note that not all students who have difficulties with these skills have dyslexia. Formal testing of reading, language, and writing skills is the only way to confirm a diagnosis of suspected dyslexia.
An individual can have more than one learning or behavioural disability. For example, in various studies as many as 30% of those diagnosed with a learning or reading difference have also been diagnosed with Attention-Deficit Hyperactivity Disorder (ADHD). Although disabilities may co-occur, one is not the cause of the other.
Visual problems
There are visual and visual perceptual (the way the brain deals with visual information) problems which can cause difficulties similar to dyslexia. These difficulties might not be detected in a standard eye test and can occur in children or adults with perfect vision. Not everyone with dyslexia will experience these visual problems, and people without dyslexia can also have these difficulties. All of these conditions can be treated.
Types of problems
- Binocular Instability: binocular vision co-ordinates the eyes. When both eyes work together, rotating and focusing, this results in a clear single image.
- Eye Movement Control: in reading, the eyes make short rapid movements interspersed with short fixations.
- When these movements are poorly controlled, it is common to miss words, lose your place in a passage or struggle to track along with a line of text.
- Meares-Irlen Syndrome also known as Visual Stress: this is a sensitivity to light, pattern and flicker which can result in distortions of the text and the illusion of the print moving or blurring. This can lead to nausea and headaches. Visual Stress is more common in people with dyslexia.
- Visual Discrimination: The ability to recognize similarities and differences between images and patterns, which is a basic requirement for reading and spelling.
- Visual Memory: the ability to recall visual information such as words and shapes. This can cause difficulties with learning sight vocabulary, spelling and letter orientation.
You may experience some of the following:
- Distortion when viewing a page of print
- Letters appear to move or jump about
- Patterns or colours in the text
- Glare when reading
- Difficulties following a line of text or column of numbers
- Sore eyes/eyestrain
- Tiredness when reading
- The blurring of words and letters
- Headaches/migraines
What can help?
An assessment by a qualified optometrist/orthoptist. It is very important to have vision assessed by someone who can look at a range of visual conditions as many of the symptoms or difficulties can be caused by more than one condition. It is also common for more than one visual or visual perceptual condition to be present.
Other things that can help
- Having a conversation with a child about what they see when they look at the text
- Removing the contrast of black text on white paper
- Using coloured rulers/overlays
- Using tinted paper to write on, rather than using white paper
- Glasses with special lenses to suit your requirements
- Performing exercises might reduce some of the difficulties
- Clear fonts, such as Century Gothic, Comic Sans or Verdana, minimum size 12
References
‘Dyslexia Friendly Formats’ and ‘Visual Issues FAQ’ at dyslexiascotland.org.uk/our-leaflets
Author Sarbind Kumar Yadav, M.Optom Senior Consultant Optometrist Ramlal Golchha Eye Hospital Foundation Biratnagar,Nepal