How many people are affected by dyslexia? How common is it?
Dyslexia is thought to be one of the most common language-based learning disabilities. It is the most common cause of reading, writing, and spelling difficulties. Of people with reading difficulties, 70-80% are likely to have some form of dyslexia. It is estimated that between 5-10% of the population has dyslexia, but this number can also be as high as 17%. The symptoms of dyslexia range from mild to severe. Because dyslexia may not be recognized and diagnosed in some individuals, they do not receive the necessary treatment; others may not disclose that they are diagnosed. These mitigating factors make the prevalence of dyslexia difficult to precisely determine.
When was dyslexia first identified?
The description of “dyslexia” was first used by a German ophthalmologist, Rudolf Berlin, when he examined a patient who suffered difficulty in learning to read and write, but showed normal intelligence and physical ability. Others described this same phenomenon around this time period, in the 1880s and 1890s, without using the “dyslexia” description. A British ophthalmologist, James Hinshelwood published a series of medical papers on the subject. In 1925, neurologist Samuel T. Orton had a patient who could not read, similar to stroke victims who lose their ability to read. In contrast, the patient had no brain damage, so Orton started to study different causes of reading difficulties unrelated to brain damage, and brought these studies to broader attention. More extensive dyslexia research has been conducted since the 1950s.
Are some people more likely to have dyslexia?
Dyslexia occurs in children with all intelligence levels. Frequently, dyslexics have above average ability. The incidence in males and females is approximately equal. Dyslexia is found all over the world, and in all socioeconomic and ethnic groups. However, children who attend ineffective schools, often in high poverty areas, are more likely to experience reading failure because of the lack of proper instruction.
Are boys more likely to have dyslexia than girls?
Although it used to be thought that more boys experienced dyslexia than girls, current research has indicated that dyslexia occurs in approximately equal proportions. One possible explanation of this myth is that boys may be more likely to act out when experiencing difficulty, while girls may try to hide their trouble. Therefore, more boys would be recognized and diagnosed with dyslexia, falsely inflating the statistics.
Are there more dyslexics now than there were previously?
Experts say that there are not more dyslexics than in previous times, but more dyslexics are correctly identified due to increased knowledge about learning disabilities.
What are common signs and symptoms of dyslexia?
Aside from difficulty with pre-literacy learning like rhyming and letter recognition, the most common sign is when a child fails to learn to read and this failure is unexpected based on his or her other abilities. Letter and number reversals past age 7 or 8 are a common warning sign. Dyslexics may also experience hardship copying from the board or a book and they may exhibit disorganization in their writing. Children with dyslexia may also appear uncoordinated and have difficulty in an organized-game setting. Symptoms may also manifest in auditory problems—the dyslexic may not be able to remember all of what he or she hears, especially sequences or multi-faceted commands. Oftentimes, the dyslexic may speak missing parts of words or sentences or use the wrong word entirely. Dyslexics have normal intelligence and often know what they want to say but have trouble actually saying it. There are also emotional symptoms. The child may become embarrassed, lose his or her interest in school, and appear lazy when in fact this is a symptom of not wanting to fail. Any of these symptoms may be present in various levels of severity. The variance in signs and symptoms is the reason why many children with dyslexia and other learning disabilities are never diagnosed. Some common symptom examples are:
- Difficulty understanding the individual sounds in words
- Difficulty remembering words
- Spoken language difficutlies, but good understanding (comprehension) of oral language
- Reversal of letters and numerical sequences
- Flipping letters and numbers and/or writing them backwards past the age of 7 or 8
- Not seeing or acknowledging punctuation in written text
- Difficulty reading different styles of type
- Omission of words while reading
- Difficulty writing
- Confusion about directions in space or time
- Inconsistencies between potential and performance
- Difficulty telling time
What causes dyslexia?
The causes of dyslexia are varied and not fully established. There are two types of dyslexia—acquired and developmental. Acquired dyslexia can be caused by ear infections early in childhood that result in hearing problems. Developmental dyslexia is caused by congenital and developmental factors; scientists believe that dyslexia has a genetic component that may predispose some people for dyslexia. Although the specific causes have not been fully investigated, neurological abnormalities are introduced in the brain, which can make it difficult for the dyslexic to read and understand information.
How is dyslexia diagnosed?
Dyslexia can be difficult to diagnose, but an early sign is that a child is not learning to read as would be expected. Language difficulties can be early indicators. The basic procedure is to gauge an individual's strengths and weaknesses in oral language, reading, spelling, and writing through standardized tests or non-standardized assessments. A child who is not performing at his or her level in spite of proper instruction may be dyslexic. Other tests examine the steps of the reading process to further determine where the strengths and weaknesses lie and where to begin remediation. It is important to determine how one processes or understands information both orally and in text, as well as how he or she expresses information verbally and in writing. Some of the common tests administered are:
- Wechsler Intelligence Scale for Children-Third Edition (WISC-III)
- Kaufman Assessment Battery for Children (KABC)
- Stanford-Binet Intelligence Scale
- Woodcock-Johnson Psycho-Educational Battery
- Peabody Individual Achievement Tests-Revised (PIAT)
- Wechsler Individual Achievement Tests (WIAT)
- Kaufman Tests of Educational Achievement (KTEA)
- Bender Gestalt Test of Visual Motor Perception
- Beery Developmental Test of Visual-Motor Integration
- Motor-Free Visual Perception Test
- Visual Aural Digit Span Test (VADS)
- Test of Auditory Perception (TAPS)
- Test of Visual Perception (TVPS)
- Peabody Picture Vocabulary Test-Revised
- Expressive One-Word Picture Vocabulary Test
- Test for Auditory Comprehension of Language
Is there a “cure” for dyslexia?
There is no cure because dyslexia is not a disease. With support, proper instruction, and hard work, many people with dyslexia are able to succeed academically and in their later lives. Dyslexia is a life-long condition, but intervention can have a positive effect on a person’s symptoms and outcomes. After an evaluation determines the specific area of difficulty and disability, it is very important that the child’s school and/or instructor are prepared to help implement a specific plan for intervention. There are many specific reading approaches that rely on a multisensory experience to strengthen the child’s weaknesses while using his/her strengths.
My child didn't have problems learning to talk; why is learning to read hard?
Talking, or oral language as we speech-language pathologists refer to it, is innate to humans as a species. We have the natural capabilities to understand and use language. Reading, on the other hand, is a cultural phenomenon (there are still societies today who exist with a purely oral tradition), and therefore it is not innate to a child's biological makeup. Without the development of written language, dyslexia would not exist.
Is it ever too late to get help for dyslexia?
No. Dyslexics can be taught strategies that can be applied throughout the lifetime. Programs involving multisensory structured language techniques have been shown to help adults as well as children. Early intervention is better, but intervention at any time can be effective.
How will my child succeed if he can't read?
First of all, with a systematic treatment approach your child will learn to read -- most dyslexics do. There are many successful dyslexics in the world! To quote acclaimed dyslexic sculptor Malcolm Alexander (featured on this site) "Find what you do best and forget about the rest." In addition to a good intervention program, your child's strengths, talents, and interests need to be fostered. Successful dyslexics talk about finding their gift and pursuing it. It is in that context that many learned to read.
How can I start to get help and where do I go to get help?
Present concerns to child’s teachers or find a professional such as a speech-language pathologist who specializes in literacy. Check the Find a Professional tab on this website.
What is the difference between all of the reading programs (e.g., Orton-Gillingham, LIPs, Read Naturally, etc.)?
There are a number of programs out there and they do differ. On this website we have provided a list of several programs and describe their varying features. All of the programs were developed for struggling readers and writers; however it is important to consult with a professional before purchasing them. It is also ideal to use these programs as a supplement to systematic, direct intervention.
What type of reading program should I enroll my child in for his/her dyslexia?
If your child has already been diagnosed with dyslexia and is receiving intervention, talking with the professional (e.g., speech-language pathologist, reading specialist, teacher, etc.) is ideal. They will have information about the programs and will be able to guide you toward making the right choice for you or your child. There are many different kinds of programs that may or may not target what best fits your needs.
If your child has not been formally diagnosed with dyslexia and you are unsure of the next steps, visit our Is My Child Dyslexic? page. Also, continue exploring the information on this website to increase your knowledge. Success starts here!
How long will my child need therapy for his/her dyslexia?
This is a difficult question to answer since everyone develops and learns at his/her own pace. You are best advised to talk with your professional about duration of therapy and how your child is responding to intervention and achieving goals. The professional will provide you with an update of prgoress based on data from the therapy sessions.
Depending on your child's age, grade, success in school, interests and desires, etc., the amount of therapy could vary. Intensive sessions may be the best way to learn a new set of skills, and then perhaps a period of less intensity for monitoring the use of those new skills. Once new skills are mastered and your child is meeting with success, the clinician may recommend taking a break.
We know that language, reading, and writing demands change as we age, and particularly while your child advances through school. Therefore, the need for therapy changes. We also know that dyslexia is lifelong. A skilled clinician can help you balance the amount and type of therapy your child needs.
What kind of technology do we need?
For most dyslexics, technology is an excellent addition to direct, systematic intervention. Check out our list of software programs designed for individuals with dyslexia and learning disabilities. It is important to remember that you should talk with a professional about what best software fits your needs or the needs of your child.
What is the difference between a reading disability and dyslexia?
There may be no difference at all. Some children may miss an important window for the development of their reading skills, and if they haven't fallen too far behind, with proper instruction can "catch up." Whereas, dyslexia manifests itself due to differences in the brain, specifically in processing phonological information; and it is lifelong.
When you go to seek help for a “reading problem”, depending on who does the diagnosis and in what context, you could walk away with a diagnosis of either dyslexia or reading disability for the very same behaviors or symptoms. In the public schools reading disability is diagnosed as a specific learning disability in written word decoding, reading comprehension, and/or written expression. In the context of our Center, we diagnose a reading problem as dyslexia if the behaviors meet the definition.
Dyslexia is a language-based learning disability and is defined as “… a specific learning disability that is neurobiological in origin. It is characterized by the 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 growth of vocabulary and background knowledge.” (Lyon, Shaywitz, & Shaywitz, 2003, Annals of Dyslexia, p. 2)
Does dyslexia only occur in English speakers?
No. Dyslexia is found across the world. It knows no cultural, language, or socio-economic boundaries.