DEAF PARENT
When a hearing child has deaf parents, the contribution of parental speech to language acquisition is necessarily restricted. This affords a test case for nativist theories. If a child can achieve language normally despite limited input, it suggests that innate processes must play a part.
Many such children do display normal acquisition, though some (possibly around 20 per cent) show signs of delayed or unusual development. What assists early acquisition appears to be oral communication with the principal carer in the form of the limited telegraphic speech which many deaf adults rely on– always provided the utterances observe the usual Subject-Verb-Object pattern and relate to local context. This affords sufficient information for a two year old to establish the basic syntactic-semantic foundations of language. The first syntactic forms which infants produce replicate those of their parents, though the productions of the infant quickly outstrip those of the parents in terms of syntactic complexity.
External factors play an important part. To ensure normal acquisition, the child appears to need a minimum of about 5–10 hours’ contact each week with hearing adults, plus exposure to radio or television. However, there is no close correlation between time spent in the company of hearers and the rate and success of linguistic development. The existence of siblings does not necessarily enhance acquisition; and some children continue to manifest linguistic problems after spending long periods with hearing peers at school.
It is remarkable that, exposed to two different forms of adult language, the child appears to avoid the simplified syntax of the deaf parents and to adopt the syntactic models provided by hearing adults outside the immediate family. If simplifications occur, they are those of all L1-acquiring infants rather than those of the profoundly deaf. Even two-year-old children appear capable of making a distinction between the type of speech they use for their parents (more signs, extended pitch patterns, shorter utterances) and the type they use with other speakers. All this would suggest to a nativist that the child is following some predetermined programme.
Against this, the intelligibility of the principal carer often appears to play an important part in determining how great a child’s language difficulties are. Certain areas of speech and language are more affected than others. Delays in phonological development are not infrequent, and the speech of some children of deaf parents may appear ‘deaf-like’.
However, the order in which the features of language are acquired seems to follow very much the same path as that recorded of infants in more normal circumstances. Furthermore, the children of deaf parents rarely show any signs of delay or impairment in pragmatic knowledge or in their ability to interact with others.
See also: Deafness, Sign language
Further reading: Schiff-Myers (1993)
