The generalization of newly acquired behaviors by parents and child across three different settings

The generalization of newly learned behaviors to different settings on the part of an autistic child and his parents was investigated by means of a multiple baseline design. Contingency management techniques were taught to the parents while they interacted with their child in a training apartment equipped with observation facilities. In order to assess whether the parents generalized the use of these techniques, data were gathered at their own home. Data were also gathered in the child's school in order to ascertain whether changes brought about in the child's behavior in the training apartment generalized to the school situation. It was concluded that the child's behavior was responsive to the contingencies of each particular environment. Generalization did not occur until the contingencies and stimulus cues were specifically designed to promote a change in behavior in each setting.     

Attending to visual or auditory verbal information while performing other concurrent tasks

Investigation of the effect that a word recognition task has on concurrent nonverbal tasks showed (a) auditory verbal messages affected visual tracking performance but not the detection of brief light flashes in the visual periphery, (b) greater impairment, both of tracking and light detections, when verbal messages were visual rather than auditory. With a kinaesthetic tracking task, errors increased significantly during auditory messages but were even greater during visual messages. There was no interaction between the modality of tracking error feedback (auditory or visual) and the modality of the verbal message. Nor was the decrement from visual messages reduced by changing the presentation format. It is suggested that different temporal characteristics of visual and auditory information affect the attentional demands of verbal messages.     

ON THE PROBLEM OF SELECTION IN ICONIC MEMORY

von W right J. M. On the problem of selection in iconic memory. Scad J. Psychol ., 1972, 1 3 , 159–171.—Conditions determining the selection of items in iconic memory were analysed. The accuracy of partial reports and the strategies adopted by the subjects varied regularly as a function of the mode of report as well as of the subject's uncertainty about the type of response he would be asked to make. By varying these factors, the apparently conflicting results of previous studies could be fairly well replicated. In optimal conditions, selection by simple physical characteristics was efficient whereas selection by class (letterslnumbers) remained difficult. Similar results were obtained when precue and postcue conditions were compared. The role of output interference and of the subjects' encoding and response strategies are discussed.     

Effects of magnitude of food reinforcement on free-operant response rates

In Experiment 1 rats were trained to press a lever on a variable-ratio schedule of food presentation and were then exposed to progressively increasing magnitudes of food reinforcement. Response running rates (rates exclusive of the postreinforcement pause) were found to increase as a function of increasing reinforcement magnitudes. The effect of reinforcement magnitude on response rates inclusive of the postreinforcement pause, however, was less pronounced. Increases in the magnitude of reinforcement were also found to increase the length of the postreinforcement pause. Rats in Experiment 2 were trained to respond on a chained differential-reinforcement-of-low-rate variable-ratio schedule, and were exposed to increasing magnitudes of reinforcement as in Experiment 1. Response running rates increased in the variable-ratio component but decreased in the other component of the schedule. The results are discussed with reference to incentive accounts of reinforcement and the action of reinforcement on the response units generated by the operative contingencies.