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Two monkeys (M. mulatto) were trained to press a telegraph key after onset of a tone and release it quickly in response to a subsequent light or click stimulus occurring after a variable interval. After training first with a fixed time limit on response latency for key release and then with a continuously adjusting limit, reaction time to click was 160 msec and to light, about 200 msec. Temporal contingencies or “payoff bands” were then introduced which reinforced only responses with latencies which fell between two limits 50 msec apart. Feedback was given as to whether each latency was too slow, within the band, or too fast. A trained monkey could precisely center its latency distribution on any 50 msec‐wide payoff band located from 200 to 600 msec after the stimulus, with from 60 to 80% of its responses achieving reinforcement. Distribution statistics were comparable to those of trained human subjects. Because such precise timing might be accomplished by a peripheral adjustment, such as changing the manner of holding the key, latency of electromyographic activation was measured in participating arm muscles in one monkey. Electromyographic activation preceded key release by a constant interval, regardless of response latency, indicating a more central mechanism for timing of brief intervals.

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On a multiple fixed‐ratio 10 fixed‐ratio 100 schedule, pigeons pause for relatively long periods of time before the fixed‐ratio 100 schedule. Only a short pause occurs before the fixed‐ratio 10 schedule. A chain fixed‐ratio 10 fixed‐ratio 100 schedule produces the reverse pattern, i.e., a short pause before the fixed‐ratio 100 schedule and a long pause before the fixed‐ratio 10 schedule. Procedurally, the only difference between the two schedules is that the fixed‐ratio 10 component is always terminated by some unconditioned reinforcer in the multiple schedule but never in the chained schedule. In the present experiment, the percentage of fixed‐ratio 10 components which included reinforcement was gradually decreased for birds on the multiple schedule and gradually increased for birds on the chained schedule. It was found that percentage reinforcement within the fixed‐ratio 10 component was inversely related to the duration of the pause before the fixed‐ratio 10 component and directly related to the duration of the pause before the fixed‐ratio 100 component. Thus, the relative rate of reinforcement paired with a particular stimulus was seen to be an important factor in determining response latency to that stimulus.

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Two bobwhite quail (Colinus virginianus) and two Japanese quail (Coturnix coturnix japonica) were trained to peck a response key to obtain food. In general, performance on fixed ratio 20 and variable‐ and fixed‐interval 60‐sec schedules was comparable to the response patterns of other species under these schedules.

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The effects of teacher behaviors on the classroom behaviors of children were investigated by systematically varying approving (praise, smiles, contacts, etc.) and disapproving (verbal reprimands, physical restraint, etc.) classes of teacher behavior. Measures were taken on both teacher and child behaviors. Each day a sample of 10 children was observed. The subject pool was a class of 28 well‐behaved children in a middle‐primary public school class. The results demonstrated that approving teacher responses served a positive reinforcing function in maintaining appropriate classroom behaviors. Disruptive behaviors increased each time approving teacher behavior was withdrawn. When the teacher's disapproving behaviors were tripled, increases appeared most markedly in the gross motor and noise‐making categories of disruptive behavior. The findings emphasize again the important role of the teacher in producing, maintaining, and eliminating disruptive as well as pro‐social classroom behavior.

The performance of rats trained on multiple variable‐interval schedules was examined before, during, and after punishment. The same linear function related relative response rates to relative density of reinforcement both in the presence and absence of punishment. Equal relative suppression was seen in both the high and low reinforcement density components. The intercept value of the function was zero. Each component of the schedule was programmed on a separate lever: thus during any component, there was an opportunity for responses on the nonoperative lever (errors). The proportions of these errors declined to a near‐zero value during punishment and did not regain their prepunishment values after punishment was removed, suggesting that some discrimination learning occurred during punishment. Recovery of response rate during punishment was seen only where a greater‐than‐zero probability of reinforcement was associated with the response.