Mothers' speech to autistic children: a preliminary causal analysis.

Changes over time in the language patterns of autistic children and their parents were examined during the course of a home-based intervention programme. Although the language used by parents to their autistic children was not deficient, language modification procedures were found to lead to rapid changes in the verbal interaction between parents and children. Parents in the non-intervention, control group showed little change in their communication style. In the experimental group, but not in the control group, a close relationship was found between increases in the use of language-eliciting utterances by their mothers and improvements in children's socialized language. The pattern of association between parent and child language suggested that the main effect was of the parent on the child but that the extent of the child's language handicap constrained what could be achieved by treatment.