Abstract
This study mainly aimed to compare two conditions (progressive and fixed time delay procedure) on a situation of cross-modal transfer. Four autistic children, who had severe speech problems, were trained the discrimination of the two kinds of visual stimuli on a sucssesive discimination setting. After the discrimination was completed, they were trained to shift a stimulus contorol from visual to auditory stimuli with two types of time delay procedures. For 3 out of 4 cases, the progressive time delay procedure was more effective in shifting of stimulus control than the fixed one. But neither of the two procedures were effective for one remaining case (Experiment 1). After the Exp. 1 was finished, 2 cases out of the 4, which were not shifted completely, were retrained with a defferential reinforcement procedure to backup the time delay procedure. This additional procedure was differed from the original time delay procedure (in Exp. 1) in terms of the reinforcement values for the two types of correct response (spontaneous and prompted). After the introduction of this procedure, their stimulus control were shifted very quickly (Experiment 2). These results were discussed from the viewpoint of the transferability between the two time delay conditions relating to the specific schedule of reinforcement (DRL).
