Generalization and maintenance of verbal commands ("mands") in two institutionalized deaf adults with mental retardation were analyzed as a function of a time-delay operation with a gestural prompt made by their caretakers. In a previous study, some operations required for changing the mode of the mand (e. g., from signing to writing) were examined in a laboratory setting; also, the results of a preliminary phase of this study showed that a time-delay with some gestural prompting was effective. Generalization and maintenance of the subjects' mands in everyday life settings were monitored from the caretakers' responses on a questionnaire as to how the subjects demanded articles that they needed to use (e. g., facial tissue). Results from this preliminary phase showed that intensive mand training in the laboratory produced no generalization of the verbal demands to everyday life settings. So, a time-delay procedure, which had been confirmed in a preliminary experiment to be effective, was systematically introduced by caretakers to demonstrate its effect. Follow-up observations over a 2-year period showed that the time-delay operation with prompts by the caretakers resulted in general in the initiation and maintenance of subjects' written or signed mands in everyday life settings. One of the two subjects increased the frequency of approaching the caretakers who had used the time-delay operation with prompting, in order to demand materials. These results showed that the time-delay operation with prompting by the caretakers functioned not as an establishing operation, which might have been maintained by negative reinforcement, but rather as a discriminative stimulus for approaching the particular caretakers who had asked these deaf subjects to make verbal demands. In other words, the long-term follow-up analysis of the maintenance of the mands showed that the verbal behavior emitted as a result of the procedures of this experiment was not a "forced" response, but rather a "spontaneous" one for demanding an object, which might be maintained by positive reinforcement.
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