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The effect of contingent nonverbal teacher approval on student attentive behavior was examined in a classroom with 12 retarded children. After baseline data were gathered on contingent verbal and nonverbal teacher approval and student attentive behavior, the teacher was instructed to increase her use of contingent nonverbal approval (smiles and physical contact) and to maintain her baseline level of verbal approval. After a reversal phase, the nonverbal approval phase was reinstated. Nonverbal teacher behaviors increased during the experimental phases, whereas verbal teacher approval (alone or in conjunction with nonverbal behaviors) did not increase. Attentive behavior increased for 11 of 12 students during the phases in which contingent nonverbal teacher approval increased. Correlational data suggested that nonverbal teacher approval accounted for behavior change of the students to a greater extent than did changes in the amount of teacher approval per se or in the teacher's use of verbal approval.

Following initial discrimination training between two wavelength stimuli and a subsequent generalization test to the wavelength dimension, Group 1 was “overtrained” for 105 days on the original discrimination. Group 2 was “overtrained” with the original positive stimulus and a new negative stimulus, a white line. Group 3 was “overtrained” with the original negative stimulus and a new positive stimulus, the white line. Each 15 days of extended training were followed by a wavelength generalization test similar to the first test. The results suggest that there is no consistent relationship between the response rate in positive stimulus immediately before the generalization test and whether or not a peak shift occurs during the test.

In discrimination training with the Lyons' blackout method, pecks to the negative stimulus are prevented by darkening the chamber each time the subject approaches the negative stimulus. Stimulus generalization along a stimulus dimension was measured after training with this method. For comparison, generalization was also measured after reinforced responding to the positive stimulus without discrimination training, and after discrimination training by extinction of pecks to the negative stimulus. The blackout procedure and the extinction of pecks to the negative stimulus both produced a peak shift in the generalization gradients. The results suggest that after discrimination training in which the positive and negative stimulus are on the same continuum, the blackout method produces extinction‐like effects on generalization tests.

The effect of social reinforcement delivered to target subjects on the attentive behavior of adjacent peers was examined in a classroom setting. In a combined reversal and multiple baseline design, two pairs of mentally retarded children were sequentially exposed to three reinforcement phases. After baseline rates of attentive behavior were obtained, praise was delivered to the target subject in each subject pair for attentive behavior. After a reversal phase, praise was delivered contingently to target subjects for inattentive behavior. In a final phase, contingent praise for attentive behavior was reinstated for the target subjects. Throughout the study, nontarget subjects received no direct reinforcers. The results indicated a vicarious reinforcement effect Reinforcing attentive behavior of target subjects increased this behavior in adjacent peers. However, reinforcing inattentive behavior of target subjects also increased the attentive behavior of adjacent peers. The effects obtained through vicarious reinforcement were considered to reflect the discriminative stimulus properties of reinforcement, which may serve as a cue for the performance of nonreinforced peers.

Rats' responding was stabilized for over 35 days on 4‐min variable‐interval reinforcement. Reinforcements per hour for 4‐sec wide classes of interresponse times were then separately controlled by adjusting those for each class to the variable‐interval values that had just prevailed. This produced little or no change in interresponse times, indicating that the new procedure was substantially equivalent to a variable‐interval schedule. The variable‐interval schedule produced a high and stable conditional probability of interresponse times in the 0‐ to 4‐sec class, associated with a peak in reinforcements per hour for this class. Reducing the reinforcements per hour for this class while raising that for another class (by 3.3 reinforcements per hour) significantly reduced the conditional probability of 0‐ to 4‐sec interresponse times. Restoring the 3.3 reinforcements per hour to the 0‐ to 4‐sec class significantly elevated the conditional probability of interresponse times in this class. Hence, it is concluded that the distribution of interresponse times produced by a subject during some variable‐interval schedules is determined partly by the relative reinforcement of different interresponse times that the variable‐interval schedule provided.(Reprinted from Part II of the Final Report of Research under Contract DA‐49‐007‐MD‐408 with the Medical Research and Development Board, Office of the Surgeon General, Department of the Army, 31 December 1954. Edwin B. Newman, Responsible Investigator; Douglas Anger, Research Assistant and author of report. Experimental work done in the Psychological Laboratories of Harvard University.)

The effects of quiet‐contingent music on the general noise levels of four seventh‐ and eighth‐grade classrooms were investigated. Following a baseline procedure, popular radio music was used to reinforce maintenance of noise below an acceptable level of intensity, 70 decibels, in three of the four classes. In the fourth class, a reversal design was used to show that the contingent presentation of the radio music was important to control the noise produced by the students. The teacher was free to engage in instructional activities because data collection and presentation of music were controlled by automatic apparatus.

Systematic use of experimenter's instructions, feedback, and feedback plus social praise was used to increase teacher praise for student attending behavior of three elementary school teachers. Experimenter's verbal interactions with teachers, teacher's verbal praise for student behaviors, and pupil attending behavior were recorded during baseline conditions. As the three successive experimental conditions were introduced first with Teacher A, then with Teacher B, in a multiple baseline design, behaviors of the experimenter, the two teachers, and eight students were measured and recorded. In the cases of Teachers A and B, experimental condition one (Instructions) and experimental condition two (Feedback) produced inconclusive results. Experimental condition three (Feedback Plus Social Praise) produced more teacher praise for student attending behavior. The entire “Package” of Experimenter's Instructions, Feedback, and Feedback Plus Social Praise was introduced to Teacher C in a single experimental condition. As in the cases of Teachers A and B, behaviors measured were: (1) the experimenter's verbal interactions, (2) the teacher's praise of students, and (3) the student's attending behavior. Introduction of the “Package” also produced more teacher praise for student attending behavior.

To increase cooperative and social behaviors in children, contingency management programs have been successfully employed. This study examined the possibility that children's social behavior might also be significantly influenced by the nature of the available play materials. Children in an urban recreation center were systematically provided with toys designed for social or isolate play. It was found that social play occurred only 16% of the time when the children were provided with “isolate” toys, whereas social play occurred 78% of the time when children were provided with “social” toys. Thus, the selection of play materials should be an important consideration in any effort to teach children social behaviors.

Two experiments demonstrated the effects of study questions on student test performance in an introductory college course. Students in both experiments correctly answered study question items 20 to 30% more frequently than non‐study question probes. Furthermore, mean performance on study question items was better than 90% during all phases of both experiments. The present experiments were also designed to study the effects of grades on test performance, and the relationship between long and short sets of study questions. The results of Experiment I clearly illustrated the importance of using grades to maintain high levels of student test performance. The results of Experiment II suggested that long sets of study questions may produce better performance on probe items than do short sets of study questions, but the effect was small.

Stimulus fading techniques were compared to those of contingency management in the treatment of a 6‐yr‐old, electively mute girl. Experimental periods consisted of the mother rewarding the child for verbal and motor responses to scheduled tasks, while a stranger slowly entered the room and then gradually administered the task items as mother left the room. A timeout contingency for non‐response to task items was also employed. Control periods consisted of a stranger administering the same tasks to the child under the same contingencies but without the presence of the mother or the use of stimulus fading. Experimental and control periods were alternated during each treatment hour. The stimulus fading procedure was found to be a necessary component of the treatment process. While the timeout contingency for non‐response was found to facilitate treatment if combined with stimulus fading, it was completely ineffective without the stimulus fading.