COMPARISON OF REINFORCEMENT SCHEDULES IN THE REDUCTION OF STEREOTYPY WITH SUPPORTED ROUTINES

The rates and durations of stereotypic behaviors in four adolescents w ith severe menial retardation were measured during two daily vocationa l training Sessions and during contiguous periods of leisure in their special education classrooms. Vocational training was conducted in two different tasks, alternating across days. The task requirements for e ach participant were matched to each participant's learning and perfor mance characteristics. The participants were exposed to a fixed ratio schedule of tokens exchangeable for food items on one task and to a va riable interval schedule for the same consequences on the second task. The schedules were chosen as an initial lest of a matching-law based prediction by Myerson and Hale (1984): Variable interval reinforcement for adaptive behavior will produce less allocation of responding to m aladaptive behavior than will a ratio-based intervention. When work pe rformances stabilized, the schedules of token delivery were reversed a cross the tasks and performances again stabilized Results are reported for periods when work performances met stability criteria. Stereotypy occurred more during leisure than during vocational training under ei ther schedule. The major differences in stereotypy between leisure and vocational training were differences in episode length rather than ra te of onset. Onset of stereotypy in vocational training, however, occu rred at higher rates under the interval schedule than under the ratio schedule in both tasks. The results are discussed in terms of Myerson and Hale's prediction and implications for further research and applic ation. (C) 1998 Elsevier Science Ltd.