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Pigeons were exposed to a procedure under which five pecks on one response key (the observing key) changed the schedule on a second key (the food key) from a mixed schedule to a multiple schedule for 25 sec. In Experiment I, a random‐ratio 50 schedule alternated with extinction. The duration of the random‐ratio 50 schedule component was varied between 1.25 and 320 sec, and extinction was scheduled for a varying time, ranging from the duration of the random‐ratio 50 to four times that value. Each set of values was scheduled for a block of sessions. Before observing‐key pecks were allowed at each set of parameter values, the pigeons were exposed to a condition where the mixed and multiple schedule alternated every 10 min, and observing‐key pecks were not permitted. Rates of pecking on the observing key were high for all values of random‐ratio component durations except 1.25 sec. Experiment II was conducted with the random‐ratio component duration equal to 40 sec, and the random‐ratio schedule was varied from random‐ratio 50 to 100, 200, and 400. Observing‐key pecking rates were high for all values of the random‐ratio schedule except random‐ratio 400. In both experiments, observing response rates were relatively little affected, suggesting that neither schedule component duration nor schedule value is a strong determinant of observing responses.

Pigeons were given a choice between observing a stimulus source that was uncorrelated with food or one that was informative. The informative source was either positive, in which a stimulus change signalled food, or negative, in which change signalled no food. If observing is supported by the reduction of uncertainty, the negative as well as the positive source should be preferred to the uncorrelated source. On the other hand, if observing requires support by conditioned reinforcement, the negative source should not be preferred to the uncorrelated source. Two keys served as stimulus sources in a discrete trial procedure. The keys were lighted together, remained on for a variable length of time, and went off together. A key could change color 1 sec before going off. In the uncorrelated source, the change occurred equally often on trials ending with or without food. In the positive information source, the change occurred only on food trials, whereas in the negative information source, it occurred only on no‐food trials. All stimulus changes and food delivery were response independent. As measured by orientation and autoshaped pecking, the positive information source was preferred to the uncorrelated source. However, the uncorrelated source was preferred to the negative information source. The latter result does not support the view that observing behavior is reinforced by the reduction of uncertainty. The positive and negative information sources reduced uncertainty equally but only the positive source provided a signal that could act as a conditioned reinforcer by virtue of its relation to food.

Pigeons were trained to peck one key when presented with white noise at any of five intensities lower than a reference intensity, and to peck another key when presented with white noise at any of five intensities greater than the reference intensity. The shape of the stimulus control curves (proportion of responses to one key versus stimulus intensity) changed from a horizontal line at the beginning of training to the sigmoid form of typical psychometric functions at the end of training. The development of stimulus control is described in terms of a model based on the theory of signal recognition and a concept of attention.

Anal sphincter pressure in a 13‐yr‐old encopretic boy was modified by reinforcing increases in pressure exerted on a fluid‐filled balloon inserted into the rectum. It was found that pressure changes were a function of the reinforcement schedule and that baseline levels (resting pressure) during extinction conditions tended to increase throughout the experiment.

Siamese fighting fish were trained to emit an operant response that was reinforced by the opportunity to view a motion picture film image of another fish. Performance under various schedules of reinforcement was examined. When reinforcement followed every response and when reinforcement was delivered after every second response, the number of responses per session was higher than during operant level or during extinction. Reinforcement delivered following intervals of no responding (differential reinforcement of other behavior) markedly decreased responding. Light from a projector without film was found to be as effective a reinforcer as film reinforcement. Responding when projector light reinforcement followed every response was maintained at approximately the same level as that obtained under film reinforcement. Responses per session decreased when only the light was delivered on a differential‐reinforcement‐of‐other‐behavior schedule. The behavior of the fish during presentation of the film was markedly different from their behavior while the projector light was being presented.

Many parts of the National Institute of Mental Health have explicit policies of encouraging research on behavior therapy. The policies about behavior therapy research of sub‐units of NIMH are reviewed, as these policies existed in fiscal year 1973. Examples are given of the type of behavior therapy research that NIMH was supporting in 1972. Particularly important is the evaluation of the efficacy of behavior therapy in comparison with standard treatment procedures.

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Peer and teacher interactions with five “disruptive” children were studied in an elementary school classroom. The intent of the study was to analyze experimentally peer reinforcement control of the disruptive children's problem behaviors. Social attention provided by all peers was found to be directed exclusively to the problem behaviors during baseline. Following baseline, several manipulations of selected peer social attention demonstrated the reinforcement function of this stimulus class.

Six pigeons were trained on a variety of concurrent fixed‐interval fixed‐interval schedules. Matching between response or time ratios and ratios of obtained numbers of reinforcements was found for eight of 12 schedules studied. Cumulative records showed both typical burst‐and‐break patterns and also atypical response patterns in which response rate was constant between reinforcements on a schedule. Matching occurred only when the same pattern was present on both concurrent schedules. When different response patterns were generated by the two schedules, the pigeons consistently emitted fewer responses to the shorter fixed‐interval than required by matching.