| Abstract: |
The milieu approach to teaching language was implemented to increase the use of a communication book by an adolescent boy with autism and severe mental retardation. A changing criterion within a multiple probe design across four different school and home environments was employed to evaluate the intervention. Once training began in each environment, the frequency of Carl's communication book use increased from an average baseline of 7% of all communication opportunities to four successively higher criterion levels. Communication book use continued to improve during maintenance while training was initiated in subsequent environments. After an average of 12 weeks of training in each environment, Carl reached the goal criterion of using his book during 75% of all opportunities. Follow-up data, taken in three of the four environments 2 to 3 months and 12 months after termination of intervention, showed that Carl had consistently maintained or improved his skill in all but the home environment, where performance had declined. Concurrent with these changes in communication, Carl exhibited an initial increase in problem behaviors over his pre-intervention rates, which was followed by a gradual, though unstable, declining trend and ended during follow-up with an average rate of once daily. Two years following intervention, his problem behaviors had declined to zero. |
