Schedule-induced behavior in children as a function of interreinforcement interval length

Two four year old twin female children were tested on fixed interval (FI) 30-, 60-, 90- and 120-sec food schedules with M&M candy reinforcers. Both subjects displayed increased drinking, gross and fine body movement, and grooming on the FI schedules as compared to Baseline conditions. Bitonic functions were noted for drinking, fine body movements and grooming for Subject J and for drinking and fine movement for Subject K, similar to those which have previously been reported in animal studies. These preliminary results demonstrated that certain behaviors may be induced by intermittent food reinforcement schedules in humans and are excessive when appropriate baselines are used for comparison. Also, these data further strengthen the species generality of schedule-induced behaviors to human subjects.