An analysis of the linguistic skills of signers with learning disabilities
This thesis explores patterns of language development in hearing children with severe learning disabilities (moderate to severe intellectual impairments) whose speech is unintelligible, and who rely on manual signs as their primary means of communication. Previous research had suggested that relatively few children reach the stage of producing multisign combinations, and that those who did so were using signs as codes for speech, rather than as an independent route to language acquisition. A series of studies was undertaken to describe the skills of a sample of 10 multi-signing children selected from a survey of 100 schools in the South of England. 'Ihis group were compared with deaf children with learning disabilities who were being educated in a signing environment. They were filmed in three contexts: picture description, conversation and story recall. The data were transcribed using a notation framework devised for British Sign Language. An initial study established criteria for determining utterance boundaries in sign. Subsequent analyses were concerned with describing patterns of semantic relations, lexical categories, word order and grammatical development in both sign and speech. Three alternative models which might account for the children's behaviour were considered:- signs as manual codes for speech; signs as gestures, and signs as elements in a bimodal process of language acquisition. The results indicated that the majority of the hearing children were functioning at a pre-syntactic level in both sign and speech. Some evidence was found to suggest that children may exploit the sign modality to produce contrasts in meaning, and that sign combinations may have independent temporal structure. Both findings are more consistent with the notion of _bimodal language development than the notion of signs as gestures or codes for speech. It was concluded that longitudinal studies of children who are highly sign-dependent are needed, to determine whether they develop syntax and morphology in this modality.