Learning disorders are characterized by performance in a specific area of learning (e.g., reading, writing, arithmetic) substantially below the expectation of a child’s chronologic age, measured intelligence, and age-appropriate education. The (DSM-IV) identifies three learning disorders: reading disorder, mathematics disorder, and disorder of written expression.
Specific learning disorders often occur in families. They are presumed to result from focal cerebral injury or from a neurodevelopmental defect.
Learning disorders are relatively common. Reading disorder affects 4% of school-age children and mathematics disorder is estimated at 1 %. The incidence of disorder of written expression is not yet known.
Learning disorders are two to four times more common in boys than girls.
History, Mental Status Examination, and Laboratory Tests
Specific learning disorders are typically diagnosed after a child has exhibited difficulties in a specific academic area. Because reading and arithmetic are usually not taught before the first grade, the diagnosis is seldom made in preschoolers. Some children may not be diagnosed until fourth or fifth grade, particularly if they have a high IQ and can mask their deficits. The diagnosis of learning disorder is confirmed through specific intelligence and achievement testing. Children with learning disorders do not obtain achievement test scores consistent with their overall IQs.
It is important to establish that a low achievement score is not due to some other factor such as lack of opportunity to learn, poor teaching, or cultural factors (e. g., English as a second language). Physical factors (such as hearing or vision impairment) must also be ruled out.
Finally, it is important to consider and test for more global disorders such as pervasive developmental disorder, mental retardation, and communication disorders. It is not uncommon to find that several of these disorders coexist. A specific learning disorder diagnosis is made when the full clinical picture is not adequately explained by other com orbid conditions.
Children with these disorders often need remedial education, especially if their diagnosis was made late.
They also need to be taught learning strategies to overcome their particular deficits. Acceptable skills in the disordered area can often be achieved with steady supportive educational assistance, though patients may be affected by these disorders throughout adulthood.
1. There are three types of learning disorders: mathematics, reading, and written expression.
2. They tend to be familial and are probably due to cerebral injury or maldevelopment.
3. Reading disorder is the most common and all three disorders occur more in boys (2-4:1).
4. The diagnosis is confirmed through achievement tests.
5. Physical or social factors must be ruled out.
6. Management involves remedial education and learning strategies.
Revision date: July 3, 2011
Last revised: by Jorge P. Ribeiro, MD