Observational studies of retarded children with multiple stereotyped movements.

Stereotyped movements, such as body rocking and hand gesturing, are common among developmentally delayed children. However, very little is known concerning the naturally occurring circumstances that produce variability in this type of responding. Three relatively long-term observational studies, involving seven preschool children, each of whom exhibited multiple stereotypies, were conducted to determine the extent to which the type of activity or setting had any effect upon the rates of these responses. Repeated observations were made of each child during a variety of school activities. In two studies, adult-child interactions were also recorded. The results showed that, in general, the particular activity greatly affected rates of stereotyped behavior, although there were some marked individual differences. Moreover, in two studies variability was apparent across sessions within a particular setting. For some of the children, there was evidence that their multiple stereotypies were functionally interrelated. Adult interactions, as recorded in one study, appear to be both quantitatively and qualitatively different for stereotyping as contrasted with nonstereotyping children. An environmental analysis employing a sequential model indicated that there were teacher behaviors that affected the frequency and/or conditional probability of the child's aberrant behavior.