It is a general term for disorders that involve difficulty in learning to read or interpret words, letters, and other symbols, but that do not affect general intelligence. Dyslexia is separate from reading difficulties caused by insufficient teaching; or either hearing or vision problems.
Symptoms: Trouble with reading, writing, and spelling. Ongoing trouble with schoolwork. Difficulty learning a foreign language. Poor handwriting. Difficulty remembering numbers. Trouble following a sequence of directions and telling left from right.
Diagnosis: To identify dyslexia, in adults or children, an IQ intelligence test is taken to see if the level is within the normal range. When a child has verbal difficulties, this can be difficult to assess fully, so both verbal and non-verbal intelligence is measured. Again, results must be within the normal range to allow a diagnosis of dyslexia to be made. The main tests used by most psychologists to determine intelligence levels in both children and adults are the various Wechsler Intelligence Scale assessments, which measure all kinds of aptitude and abilities, from verbal comprehension to perceptual reasoning, processing speed to working memory.
Treament: Effective treatment of dyslexia is based upon an amazing truth that brain science has lately uncovered: the brain is able to change and strengthen, just like a muscle, if exercised in the right way. Think of a body-builder, who puts stress on his muscles to make them stronger. Now, when the same techniques are applied to the brain (through cognitive exercises) disorders like dyslexia can be improved, because the weak areas of the brain that are causing dyslexia can be strengthened so they will to work properly. A cure for dyslexia and other learning disabilities was previously believed to be impossible; it was thought that intelligence was fixed, and unchangeable.
Epidemology: The percentage of people with dyslexia is unknown, but it has been estimated to be as low as 5% and as high as 17% of the population. While it is diagnosed more often in males,some believe that it affects males and females equally.