[Combined verbal and sign language for promoting communication development in non-verbal or or pre-verbal children and adolescents with mental retardation].

Conveying alternative and augmentative approaches to communication is becoming necessary for increasing numbers of persons with mental retardation with no or poor oral skills. The preverbal and nonverbal forms of communicating, hence, have special relevance in a developmental context. A natural extension of gestic messages, it in particular is the use of signing that is apt to enhance speech and language acquisition and bring about distinct improvement in understanding and making oneself understood. Exchanging messages by sign language can reveal to the child the significance of his/her own behaviour in the communicative situation, hence reduce passiveness and frustration. The extent to which they are able to support the child's communicative needs in concrete, everyday living is an important suitability criterion also for the various other alternative and augmentative communication devices available.