Communication disorders are among the most common disorders in childhood. To communicate effectively, children must have a mastery of language—that is, the ability to understand and express ideas—using words and speech. Whereas language disorders include expressive and mixed receptive-expressive language disorder, speech disorders include phonological disorder and stuttering. Children with expressive language disorders have difficulties expressing their thoughts with words and sentences at a level of sophistication expected for their age and developmental level in other areas. These children may struggle with limited vocabularies; speak in sentences that are short or ungrammatical; and often present descriptions of situations that are disorganized, confusing, and infantile. They may be delayed in developing an understanding and a memory of words compared with others their age.

Language competence spans four domains: phonology, grammar, semantics, and pragmatics. Phonology refers to the ability to produce sounds that constitute words in a given language and the skills to discriminate the various phonemes (sounds that are made by a letter or group of letters in a language). To imitate words, a child must be able to produce the sounds of words. Grammar designates the organization of words and the rules for placing words in an order that makes sense in that language. Semantics refers to the organization of concepts and the acquisition of words themselves. A child draws from a mental list of words to produce sentences. Children with language impairments exhibit a wide range of difficulties with semantics that include acquiring new words, storage and organization of known words, and word retrieval. Speech and language evaluations that are sufficiently broad to test all of the above skill levels are more accurate in evaluating a child’s remedial needs. Pragmatics has to do with skill in the actual use of language and the “rules” of conversation, including pausing so that a listener can answer a question and knowing when to change the topic when a break occurs in a conversation. By age 2 years, toddlers may know up to 200 words, and by age 3 years, most children understand the basic rules of language and can converse effectively (Table 40.1).

Students should study the questions and answers below for a useful review of these disorders.