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Seven rats were trained to stable performance levels on either Fixed Ratio 47, Variable Ratio 47, Variable Interval 1‐min, or Fixed Interval 1‐min schedules of food reinforcement. Subjects were then tested for sensitivity to vestibular stimulation from rotation, using an ascending method of limits technique with increments in velocity of one revolution per minute every 5 min. Centrifugal forces were minimized by locating the test chamber over the axis of rotation. Response rates decreased in all subjects as a function of increasing rotation speed. In addition, characteristic differences in the patterns of response decrement were found between subjects on ratio and on interval schedules. Repeated tests indicated high intra‐subject reliability in sensitivity to rotation. Similarities of these data to “motion sickness” phenomena in other species were noted. It is suggested that this behavioral approach provides a sensitive and quantifiable technique for assessing the effects of vestibular stimulation in animals.

A progressive‐ratio reinforcement schedule, in which successive reinforcements required an additional 50 responses, was programmed on one key. A response on a second key reset the progressive‐ratio schedule to the first step. Before punishment, all pigeons consistently reset the schedule after reinforcement on the first step, thereby minimizing the number of responses required for reinforcement. Punishment was a brief electric shock contingent upon each response on the reset key. The first effect of punishment was to change the frequency of extra responses on the reset key. Under higher intensities of punishment, the pigeons completed the advanced steps of the progressive‐ratio schedule before resetting to the first step. Completions of advanced steps were accompanied by decreases in the overall rate of responding and the rate of reinforcement. When the punishment contingency was removed, the major features of pre‐punishment performance were recovered.

An attempt was made to vary systematically the behavior of two elementary school teachers to determine the effects on classroom behavior of Rules, Ignoring Inappropriate Behaviors, and showing Approval for Appropriate Behavior. Behaviors of two children in one class and one child in the other class were recorded by observers, as were samples of the teachers' behavior. Following baseline recordings, Rules, Ignoring, and Approval conditions were introduced one at a time. In one class a reversal of conditions was carried out. The main conclusions were that: (a) Rules alone exerted little effect on classroom behavior, (b) Ignoring Inappropriate Behavior and showing Approval for Appropriate Behavior (in combination) were very effective in achieving better classroom behavior, and (c) showing Approval for Appropriate Behaviors is probably the key to effective classroom management.

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Responding was maintained in two squirrel monkeys under several variations of a 10‐min fixed‐interval schedule of electric shock presentation. The monkeys were first trained under a 2‐min variable‐interval schedule of food presentation, and then under a concurrent schedule of food presentation and shock presentation. In one monkey, when shocks (12.6 ma) followed each response during the last minute of an 11‐min cycle ending with a timeout period, responding was increased during the first 10 min and suppressed during the last minute of each cycle. When the shock schedule was eliminated, both the enhancement and suppression disappeared, and a steady rate of responding was maintained under the variable‐interval schedule. When the food schedule was eliminated, the shock schedule maintained a characteristic fixed‐interval pattern of responding during the first 10 min, but suppressed responding during the last minute of each cycle. The fixed‐interval pattern of responding was maintained when the timeout period was eliminated and when only one shock could occur at the end of the cycle. In the second monkey, responding under the concurrent food and shock schedule was suppressed when responses produced shocks after 3‐min. Under an 11‐min cycle, responding continued to be maintained at increasing shock intensities. When the food schedule was eliminated, a fixed‐interval pattern of responding was maintained under a 10‐min schedule of shock presentation (12.6 ma). Whether response‐produced electric shocks suppressed responding or maintained responding depended on the schedule of shock presentation.

Pigeons' pecks on either of two concurrently available response keys produced secondary reinforcers according to independent one‐minute variable‐interval schedules. Different secondary reinforcers, in the presence of which the rates of primary reinforcement were equal, were associated with each key. The rate of pecking maintained by each secondary reinforcer varied directly, but nonproportionally, with the number of primary reinforcements given in the presence of the secondary reinforcer.

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The relative importance of interreinforcement time and interreinforcement responses was evaluated by varying each independently. To do this, a blackout was presented after each non‐reinforced response under both fixed‐ratio and fixed‐interval schedules of reinforcement. Manipulating the blackout duration under the fixed‐ratio schedule caused interreinforcement time to vary without affecting the number of interreinforcement responses. Pigeons' post‐reinforcement and post‐blackout response latencies were found to increase linearly with interreinforcement time. Under the fixed‐interval schedule, the same blackout manipulations changed the number of interreinforcement responses without affecting interreinforcement time. Post‐reinforcement and post‐blackout response latencies under this condition were approximately constant. These results suggest that responding is controlled by interreinforcement time and is not influenced by the number of responses emitted between reinforcements.