Dyslexia

What Is It?

Dyslexia is a learning disability that makes reading difficult for children and adults who otherwise have the intelligence and motivation necessary to learn to read. Although people with dyslexia have trouble understanding words they read, they usually can understand the same words when they are read aloud by another person.

Researchers don't know exactly what causes dyslexia, but they think there may be a problem during development that affects the way the brain processes information. They also believe that genetics (inheritance) plays a part. Although a gene for dyslexia has not been found, dyslexia does tend to run in families. Dyslexia is not caused by a physical disability, such as vision or hearing problems. Many people with dyslexia have average or above-average intelligence.

Dyslexia is the most common learning disorder. In the United States, approximately 5 percent to 10 percent of the population probably has some level of dyslexia.

Symptoms

A person with dyslexia may have difficulty with the following tasks:

• Identifying words
• Recognizing the sounds that make up words
• Understanding and remembering what is read
• Translating printed words into spoken words
• Spelling
• Organizing or sequencing thoughts
• Rhyming words
• Learning the alphabet and numbers during preschool and kindergarten

Some people with dyslexia tend to reverse or misread letters or words. For example, they may mistake the letter "b" for "d" or read the number "6" as "9." They may read the word "was" as "saw" or may switch the order of words in a sentence. For example, they may read "are there" instead of "there are." They also may see words as having incorrect spacing — either with odd spacing or no spacing at all.

Because of these difficulties, a person with dyslexia usually reads slowly and may hesitate often.

Dyslexia is not a vision problem. The eyes do not actually see words incorrectly, but the brain apparently has difficulty processing the visual information.

It is important to note that many young children reverse letters and numbers, misread words or misunderstand words as a normal part of learning to read. Children with dyslexia, however, continue to do so after their peers have stopped, usually by first or second grade. Dyslexia may not be recognized until a child starts school, when a student of normal intelligence begins to lag behind his or her peers in academic performance.

Diagnosis

Your doctor will ask about your child's medical, developmental and family histories and will examine him or her to check for possible physical causes that could make reading difficult, such as hearing or vision problems. He or she also will look for signs of other problems that could be causing your child's reading difficulties. These could include motor-coordination disorders, attention-deficit hyperactivity disorder (ADHD), depression, anxiety and thyroid disorders. If no physical causes are found, the doctor may refer your child to a learning specialist for evaluation. Testing for learning disabilities often is done by psychologists or education specialists at schools or hospitals.