Introduction
Learning disabilities are developmental disorders where there is a discrepancy between the learning potential and the current level of school performance. This is measured by tests that evaluate both the present knowledge and the intellectual capabilities. Learning disabilities are more common in boys than in girls (ratio of 5:1). There are a number of different types of learning disabilities. A learning disability may affect concentration and attention; it may affect the processing of visuals or sounds; or it may affect language development. Diagnostic tests require a battery of tests including psychological and medical tests. Treatment is directed against the weaknesses that were identified by the testing and usually consists of a combination of special educational approaches, management skills and psychological counseling. About 5% of the school population in the US receives special needs education (Ref.1), but when minor learning problems are included, there likely are about 10% of children and adolescents who have some form of learning disability. In many development countries about 30% of children under the age of 15 have learning disabilities. The reason for this is that many of these children are exposed to iron deficiency. Also, in many regions of China, Central Africa and in South America iodine deficiency is common (untreated hypothyroidism interferes with the capacity of learning). When children are exposed to malnutrition, which interferes with normal brain development, they are particularly vulnerable to getting learning disabilities. It has been shown that exposure to malnutrition during the first year of life will cause reduced school performance in up to 70% of these children (Ref.2). Children with learning disabilities have usually normal intelligence, but there are areas of weaknesses where they need help.
Symptoms
Usually it is early on in the school system that learning disabilities are recognized. The teacher is most likely the one to suggest that there could be a learning disability. Affected children may have problems memorizing the alphabet. There may be limited speech perception and a limited vocabulary. The teacher may observe that the child does not understand what is read. The handwriting may look messy; the child may have a problem retelling a story in the same sequential order. In math there may be a problem with misreading numbers or confusing math symbols. Any of these problems, a delay in reading skills or a delay in listening skills is a powerful predictor that the person will have problems in higher grades. It is in these higher grades that the child with a learning disability will have more serious problems and likely will drop out of school. The child simply cannot keep pace with the more demanding tasks required such as more abstract thinking, reasoning, organizational skills, spatial memory, visual memory etc. Other symptoms may be present that come from associated other conditions. Frequently there are various degrees of other psychiatric conditions present such as depression, anxiety, attention deficit disorder (ADHD), conduct disorder and others. Each of them have their unique set of symptoms that is interwoven with the symptoms of learning disabilities.
Learning Disabilities
Diagnosis
In order to measure the deficiencies in skills and cognitive functions comprehensive testing is required. This includes testing of speech and language, doing educational and intellectual tests as well as psychological and medical tests. In children with a brain injury neuropsychological testing is required, which will be able to pinpoint what area of the brain is not functioning. To measure intelligence the Wechsler test is used. Three types have been developed for various age groups. The WPPSI-R is for the ages of 3 years to 7 years. The WISC-III test is for the ages of 6 years to almost 17 years. The WAIS-III test is for the age of16 years to almost 75 years. With the Wechsler test Verbal IQ, Performance IQ and Full Scale IQ are determined. Another intelligence test for verbal ability is the Peabody Picture Vocabulary Test-Revised, where the person is asked to identify which of 4 pictures best summarizes a spoken word. The Raven’s Progressive Matrices Test is a test for nonverbal abstraction; abstract principles and rules need to be deducted from patterns that are shown. Academic achievement is checked by testing skills in reading, writing, arithmetic skills, and spelling. Neuropsychological and educational abilities are assessed in this way. One of the routine tests for this is the Peabody Individual Achievement Test-Revised (PIAT-R). In addition the Wide Range Achievement Test-Third Edition (WRAT-III) is used for that purpose. There is a whole array of further tests available that are used depending on the special circumstances. Details can be found under Ref.3.
Treatment
The treatment of learning disabilities has to be individualized, but at the same time needs to be comprehensive. The test results are a guide to individualize treatment. Weaknesses have to be acknowledged and strengths need to be strengthened more. Curriculum modifications are done in special education classes. Individual and family counseling is done. Some children who have attention deficit disorders will benefit from stimulant medication. When depression or anxiety is part of the symptom complex, antidepressants and anxiolytics may have to be used parallel to the educational and counseling interventions. A pediatrician likely should supervise the treatment protocol of the youngster. The parents need to be warned about ineffective treatments that are often offered by alternative medicine practitioners. Dietary regimens, neuromotor programs, eye exercises, biofeedback and others are only some of the controversial therapies that are offered, but have been found to be ineffective (Ref.4). Consult a pediatrician to get advice whether or not a certain treatment would be effective.
References:
1. Schopler E, Reichler RJ, Renner BR: The Childhood Autism Rating Scale (CARS), Los Angeles, Western Psychological Services, 1988.
2. Jacobson: Psychiatric Secrets, 2nd ed. Copyright © 2001 Hanley and Belfus Section Seven – DIAGNOSIS AND TREATMENT OF PSYCHIATRIC DISORDERS IN CHILDHOOD AND ADOLESCENCE ; Chapter 55 – AUTISM SPECTRUM DISORDERS
3. The Merck Manual, 18th edition, Merck Research Laboratories, © 2006. Chapter 299: Learning and developmental disorders.
4. Lord C, Rutter M, LeCouteur A: Autism Diagnostic Interview—Revised: A revised version of a diagnostic interview for caregivers of individuals with possible pervasive developmental disorders. J Autism Dev Disord 1994; 24:659-685.
5. Lord C, Rutter M, Di Lavore PC: Autism Diagnostic Observation Schedule—Generic, Chicago, University of Chicago Department of Psychiatry, 1998.
