[What are specific performance weaknesses?].

The term "specific developmental disorder" means localized deficits in very different functions contrasting fit in the general otherwise normal performance level of a child. These disorders are mostly looked upon in a developmental context and differentiated from acquired neuropsychological syndromes (e.g. aphasia, apraxia). The most important clinically relevant disorders are: the specific reading disability, the specific dyscalculia, other specific learning disabilities, the specific developmental language disorder, the specific retardation in the motor development, and multiple developmental retardations. In a population of all patients treated in institutions for children and adolescents, 30% show specific developmental disorders with a predominance of boys. There is no correlation between dyslexia and social class but it does exist for specific developmental language disorder and motor retardation. As to the etiology of specific developmental disorders, genetic factors, congenital or acquired cerebral dysfunctions, maturation or developmental retardation and cognitive variables are discussed. The multifactor-approach seems to be the best way of understanding specific developmental disorders, which are difficult to prove.