Dyslexia Fact Sheet
Introduction to Language
There are 26 letters in the English alphabet and these letters represent approximately 40 unique spoken sounds (phonemes). These 26 letters combine to construct over half a million words in the English language, although the average educated person uses 2,000 unique words to communicate on a daily basis. It is astonishing to think that these 26 letters can be arranged in an infinite number of patterns so that 400,000 books are published in the United States and United Kingdom every year and over one trillion web pages exist worldwide. Those 26 letters can be put together to represent a birthday wish on a greeting card, a grocery list, a high school book report, or a Supreme Court decision. The lexis (of Greek origin, meaning “word”) of a given language is the storage of language in our brains as prefabricated patterns (or lexical units) that can be recalled and sorted into meaningful speech and writing. As such, the lexis is all that can potentially be communicated by a language.
The neurological and learned ability to read all of that information is extraordinarily powerful and almost a necessity for a successful personal life. That is why difficulty learning to read is equally and profoundly disrupting.
Definition of Dyslexia
The National institutes of Health states that dyslexia is a specific learning disability, impacting five to ten percent of the population, that results from a dysfunction of one or more of the neurological processes in the brain. Dyslexia is characterized by frequent inaccuracies in word recognition, a lack of fluency (or “smoothness”) in word recognition, and by poor spelling and decoding abilities. These difficulties stem from a deficit in the phonological (sound system) component of language, despite having the cognitive ability to learn, and despite effective classroom instruction. Dyslexia is simply trouble with words (the lexis).
By this definition, dyslexia is not simply difficulty reading, and therefore must be distinguished from other causes of difficulty learning to read such as impaired vision or hearing difficulties, or poor reading because of inadequate instruction or schooling.
Frequency and Diagnosis of Dyslexia
It is difficult to determine how often dyslexia occurs, because of lack of agreement on diagnostic methods, especially in adults. Most studies indicate that about 5 – 10% of the entire population has dyslexia, but the actual numbers may be higher.
It is important to understand that there are many different reasons why children have trouble learning to read, of which one cause is dyslexia. In order to distinguish the different causes and proscribe the best treatment, it is essential to have a thorough evaluation by a clinician experienced in childhood learning. There are many different professionals who perform these evaluations, but generally the evaluation is performed by a clinical or school psychologist. A psychiatrist, neurologist, or developmental pediatrician may help interpret the evaluation results and put the results in the context of the child’s (or adult’s) overall health and development.
Symptoms of Dyslexia
No two children with dyslexia will present with exactly the same symptoms, but most children with dyslexia will experience the following:
Pre-school age children
It can be difficult to recognize dyslexia in a child before reading instruction actually begins. But in retrospect, children who are later diagnosed with dyslexia often exhibit the following during their pre-school years:
- Difficulty learning rhymes
- Slow with naming colors, objects, etc.
- Difficulty learning and remembering the alphabet
- Difficulty recognizing letters and remembering their names
- Difficulty telling you what letter or sound is at the beginning of a word (“What sound does 'dog' start with?”)
- Difficulty associating the appropriate sound with a letter (sound/symbol association)
Early elementary school-age children
- Letter Reversals (“b” for “d”) and Word Reversals (saw for was). (Letter and Word Reversals are common in all young children, but they usually disappear by 7 years of age. However, they usually persist in children with dyslexia.)
- Trouble appreciating rhyming, sound, or word games
- Confusion with words that are similar (e.g., heart/hurt, deaf/death, department/apartment)
- Mispronunciations (e.g., “simple” for “sample”)
- Confusing sounds in multisyllable words (for example, "aminal" for animal, "pasghetti" for spaghetti)
- Difficulty distinguishing syllables in words
- Difficulty segmenting words into individual sounds, or blending sounds to make words
- Difficulty naming pictures of objects
- Confusion with before/after, right/left, over/under, and contrasting concepts
Older elementary school children
- Trouble with manipulating sounds in words such as with “pig Latin”
- Trouble appreciating rhyming, sound, or word games
- Difficulty finding the right words when speaking
- Slow or inaccurate reading; trouble sounding out words
- Reading word by word (lack of fluency in reading)
- Very poor spelling
- Difficulty identifying the accurate meaning of words
- Difficulty with written expression
Associated Symptoms with Dyslexia
If a person has dyslexia, it is present all of his or her life, and it is difficult to predict how any one person will react to this disability. Because reading comes so easily to others, it is not uncommon to see children teased by peers and berated for being lazy by teachers. Some children act out with frustration and behavioral changes, while others withdraw with low self-esteem, anxiety, or depression. Some people excel in another area (e.g., music, drama, or athletics), and with help, most people can lead happy, productive, and successful lives (e.g., Winston Churchill, Anderson Cooper, Bruce Jenner).
What Causes Dyslexia?
The cause of dyslexia is unknown, but we do know that dyslexia results from a dysfunction of one or more of the neuro-biologic processes in the brain. A strong genetic tendency towards dyslexia can be seen in many families, suggesting that the underlying cause is genetic. Microscopic disruption of the normal architecture of the brain has been identified in many individuals with dyslexia. This is due to problems with the migration of neurons as the brain develops. These disruptions can be found in almost all human brains, but in dyslexia there are more than usual. They are found in the areas of the brain that are important for language processing, affecting the pathways needed for efficient oral and written language development.
Almost all children with dyslexia have difficulty with the phonologic system of language – phonological awareness. Phonological awareness refers to the ability to detect or manipulate the sounds in words that are heard. It develops during pre-school years, progressing from phonological sensitivity (the ability to recognize that words are made of bits of sounds, such as with rhyming) to phonemic awareness (the ability to recognize and manipulate individual sounds, or phonemes, in words). Phonemic awareness is the essential ability to perceive that words are made up of a unique combination of sounds and that the order of those sounds is of critical importance. Children with poor phonemic awareness have difficulty learning the sound/symbol relationships essential for sounding out words, a skill that is necessary to become an efficient reader. New words cannot be sounded out, so children with dyslexia often try to rely on memorization, sight word reading, and/or guessing. Reading therefore becomes laborious and frustrating.
While research has shown that the major cause for most reading disabilities is weak phonemic awareness, there may be other factors present that compound the difficulty, such as attention problems, auditory or visual processing problems, and/or difficulty with eye-tracking. Fortunately, genetics does not mean there is nothing to be done! The brain has the ability to constantly change and rebuild itself, and learning shares equal importance with the genes. The neuronal migrations affect only a small part of the brain. Effective treatments have been developed and researched, and if administered correctly, can result in the brain pathways needed for developing and strengthening phonemic awareness and the ability to sound out words for efficient reading. If other learning weaknesses co-exist, additional treatments are available as well.
Learn more about how children with dyslexia excel at Lexis Prep.