Developmental Dyslexia: An Update
Ruth Nass MD1
1 Departments of Pediatrics and Neurology, New York Hospital-Cornell Medical Center. Address reprint requests to Dr. Nass: Rusk Research-Room 212, New York University Medical Center, 550 First Avenue, New York, NY 10016, (212) 263-7753
Definitions
Developmental dyslexia, also known as specific reading disability, is an unexpected difficulty in learning to read that occurs in the otherwise normal child. Rudel1 suggests it be defined by both exclusionary and inclusionary criteria. Her strict definition requires that five criteria be met: 1) The child must have no major neurologic abnormalities, such as overt cerebral palsy. Affected children may and often do have "soft" signs on neurologic examination, however. 2) The major sensory functions must be normal; the child cannot be blind or deaf. Practically speaking, children who are blind or deaf or who have cerebral palsy may be dyslexic if they have reading difficulties disproportionate to their other academic and intellectual abilities. 3) The child should have no major psychiatric problems. Problems with self-esteem are often, however, a reactive secondary issue in the child who has a learning disability. 4) Normal intelligence is required, using either a verbal or nonverbal measure. Children who have dyslexia often also have language problems. Hence, verbal intelligence scores may not reflect overall intellectual abilities accurately. 5) Finally, the dyslexic child must have been in a social and educational environment conducive to learning to read. Several studies of inner-city school children have demonstrated that enrichment programs help some nonreaders become readers, demonstrating the importance of teaching techniques.
