We studied the effect of training conversational expansions on conversational initiations in six adults with intellectual handicaps. Generalization was assessed in weekly probe sessions consisting of conversations with an unfamiliar person in a community setting. Results indicated that training for expansions was successful for all but one subject and that generalization of this skill increased for all those subjects who succeeded in training. The frequency of initiating conversations increased concurrently without any explicit training, indeed, initiations were ignored during training. In three cases inappropriate verbalizations decreased without explicit training, which might have been due to multiple contingency time constraints, but might also have resulted from an implicit extinction procedure. Based on these results and previous research it was suggested that the conversational expansions and initiations had formed a functional response class through their commonly occurring natural contingencies.
Six common sources of contingencies are suggested, to provide an overall framework for analysing behavior and taking account of the many variables which control human behavior. Controlling contingencies can be produced by the physical environment, by multiple contingency interactions, by meta-contingencies, by social behavior without a verbal community, by verbal communities, and through social rituals which reinforce behaviors that maintain the verbal communities. Different interventions are briefly suggested which are appropriate for each source of contingency. An example is given of how we might analyse smoking behavior and how smoking has been controlled by interventions appropriate to the six sources of control.