Three questions are raised with respect to the use of sign language as an alternative system of communication for nonverbal autistic children. First, does teaching a child to sign facilitate speech development? The data suggest that following simultaneous communication training, mute children are not likely to learn to talk; however, a combination of simultaneous communication training and separate vocal training may have a synergetic effect on speech development. In contrast, children who initially have good verbal imitation skills apparently show gains in speech following simultaneous communication training alone. Second, what is the upper limit of sign acquisition? Data suggest that abstract concepts, syntax, and generative skills can be taught. Procedures used in the operant conditioning of speech may prove useful in training complex signing skills. Third, does sign acquisition result in a general improvement in adaptive functioning? It appears that following sign training, some children do show increases in spontaneous communication, decreases in self-stimulatory behavior, and improvement in social skills. However, these outcomes are often difficult to interpret. Some data are described that help clarify the relationship between sign training and general behavioral improvement.
