Language disorders.

Developmental language disorders (DLD) are prevalent and persistent among school-age children but are often underrecognized. This chapter discusses the ways in which the various components of communication are impacted by these disorders and outlines the differences in expression seen in different languages. Research on biological and psychologic roots of the syndrome is also reviewed. As yet, no single definitive cause has been identified; the disorders are likely to result from a constellation of genetic, biological, and cognitive weaknesses that are influenced by environmental experiences. Basic methods of assessment and differential diagnosis are presented and the principles guiding the development of intervention programs are discussed.