Date of Award
Dissertation - Restricted
Doctor of Philosophy (PhD)
Cross-linguistic studies (Bowerman, 1973a; Brown, 1973) have indicated that the infant's first spoken words usually emerge by the end of the first year of life. With American children, it has been documented that by 18 to 24 months, the length of utterance increases to two words or morphemes (McCarthy, 1930; Miller and Chapman, 1981; and Templin, 1957). A morpheme is a linguistic unit which can be a word or an inflection such as -s, -ing, -ed. Miller and Chapman (1981) included a sample of 123 children from Wisconsin between the ages of 17 months and five years. They observed that by 36 months of age their subjects were generally using three morphemes per utterance, at 45 months four morphemes, and at 54 months five re0rphemes. When a child does not acquire these speech and language milestones at the expected time, it is often a cause for concern on the part of the parents. It is not uncommon for such parents to seek professional help for their child in the form of speech and language evaluation and therapy. Children with slow speech and language development have also been the focus of study by a wide range of disciplines including linguistics, neurology, and psychology. In spite of all this interest and concern, the state of the art on language development and language disorders in children is still very much in its infancy.
A review of the literature has revealed that children with slow speech and language development have been identified by a variety of different labels including: delayed speech (Morley, Court, and Miller, 1955), aphasic (Eisenson, 1966, 1968a, 1968b), immature speech (Menyuk, 1964), dysphasic (Weiner, 1972), language deviant (Morehead and Ingram, 1972), and language impaired (Hall and Tomblin, 1978). The problem with most of these terms is that they assume that the child has some sort of deficiency, or they presuppose a specific etiology such as brain damage. Neither of these assumptions has been proven. Therefore, many clinicians have preferred the term language delayed, which suggests that the language development of the child is similar to that of a younger child with normal language skills . However, in contradiction with this suggestion, research by Menyuk (1964),
and Menyuk and Looney (1972) has indicated that so-called language delayed children do not acquire the same syntactic structures that normal children do. While not everyone has agreed with Menyuk, and MenJuk and Looney's findings (Leonard, 1979; Morehead and Ingram, 1973), the lack of agreement still indicates that an appropriate term for children with slow and/or abnormal language development is needed. Bloom and Lahey (1978) have pointed out the advantages of applying the term language disordered to children who have not acquired language milestones at the expected rate. Language disordered seems to be the most satisfactory term suggested because it describes the problem without the added assumptions of deviance versus delay. Furthermore, language disordered is a description which makes no speculations regarding etiology, an area that begs more questions than it answers. Therefore, "language disordered" is the term that will be used by the present author to identify children who have been slow to achieve normal language development.
Before reviewing the major theories on language disordered children, it is important for the reader to be aware that the terms speech and language are not synonymous. Speech has to do with the oral-motor mechanism of language, i.e., the combined movements of the lips, tongue, and other articulators which produce the sounds that result in words, phrases, and sentences (Buckingham, 1979). Language, on the other hand, is a code whereby human beings represent ideas about the world for purposes of communication (Bloom and Lahey, 1978). Aside from speech, language may be represented through gestures, written expression, or even pictures. It is quite possible for a person to have language in the absence of speech, as is the case with deaf persons who communicate through sign language.