Oral motor and language development.

Manual gesture has been shown to be related to normal language development, in that early gesture users become early talkers. In addition, different groups of speech and language impaired individuals (left-hemisphere CVA patients with nonfluent dysphasia, and the affected members of the KE family, who have a severe developmental speech and language disorder) have been shown to have difficulties with complex oral movements. However, infants' gross and fine motor development does not correlate with their language development. It is usually suggested that gesture is a communicative precursor to language use, and some interpretations of the data from language impaired individuals suggest either damage to or lack of development in closely related physically but functionally unrelated areas. The relation between speech and language and motor function remains unclear. This study investigates the link between oral motor development, which is not communicative per se, and language development in normally developing 2-year-olds, an age at which this development is usually very rapid, in an attempt to determine if there might be some relation between communicative development and motor development. A battery of simple movements (using only one set of muscles), complex movements (using more than one set of muscles) and repeated movements (testing for rate and accuracy) were used. Children were required to imitate the tester, with various toys and props provided (e.g. a wolf puppet with a tongue to cue mouth opening and tongue protrusion). Parents completed the Communicative Development Inventory, including vocabulary and grammatical complexity scales. Significant relationships between some aspects of oral motor functioning and language use were found. The results are discussed in the light of theories of language development generally, including those that suggest an intrinsic independence of language development from other aspects of development, and the two-year-old acceleration of language use in particular