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Several researchers have suggested that conditioning history may have long-term effects on fixed-interval performances of rats. To test this idea and to identify possible factors involved in temporal control development, groups of rats initially were exposed to different reinforcement schedules: continuous, fixed-time, and random-interval. Afterwards, half of the rats in each group were studied on a fixed-interval 30-s schedule of reinforcement and the other half on a fixed-interval 90-s schedule of reinforcement. No evidence of long-term effects attributable to conditioning history on either response output or response patterning was found; history effects were transitory. Different tendencies in trajectory across sessions were observed for measures of early and late responding within the interreinforcer interval, suggesting that temporal control is the result of two separate processes: one involved in response output and the other in time allocation of responding and not responding.

The study examined the effect of guided imagery on overt social behavior of children during free play. Forty withdrawn and rejected first-graders (6 to 8 years of age) were randomly assigned to one of five conditions. Four of them were guided imagery conditions: mastery plus peer acceptance, mastery with no social contingency, coping, and gradual rehearsal. A fifth control condition involved no intervention. It was predicted that the four imagery conditions would increase and maintain positive socialization, but the coping condition would be the most effective. Children under the coping condition, which involved guided imagery of failure to get peer acceptance, but progressively mastering the social interaction and finally being accepted by peers, consistently increased positive socialization behaviors from baseline to post-treatment and follow-up, as compared to gradual rehearsal and control. Both mastery conditions increased socialization at post-treatment, but reverted to baseline levels during follow-up.

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