Developmental disorder

Developmental disorders comprise a group of psychiatric conditions originating in childhood that involve serious impairment in different areas. There are several ways of using this term. The most narrow concept is used in the category "Specific Disorders of Psychological Development" in the ICD-10. These disorders comprise developmental language disorder, learning disorders, motor disorders, and autism spectrum disorders. In broader definitions ADHD is included, and the term used is neurodevelopmental disorders. Yet others include antisocial behavior and schizophrenia that begins in childhood and continues through life. However, these two latter conditions are not as stable as the other developmental disorders, and there is not the same evidence of a shared genetic liability. Developmental disorders are present from early life onward. Most improve as the child grows older, but some entail impairments that continue throughout life. Learning disabilities are diagnosed when the children are young and just beginning school. Most learning disabilities are found under the age of 9. Young children with communication disorders may not speak at all, or may have a limited vocabulary for their age. Some children with communication disorders have difficulty understanding simple directions or are unable to name objects. Most children with communication disorders are able to speak by the time they enter school, however, they continue to have problems with communication. School-aged children often have problems understanding and formulating words. Teens may have more difficulty with understanding or expressing abstract ideas. The scientific study of the causes of developmental disorders involves many different theories. Some of the major differences between these theories involves whether or not environment disrupts normal development, if abnormalities are pre-determined, or if they are products of human evolutionary history which become disorders in modern environments (see evolutionary psychiatry).