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An attempt was made to reduce the cigarette smoking of three subjects by means of a special cigarette case that delivered aversive shock when opened. The number of cigarettes smoked was recorded by a counter in the cigarette case. The validity of the counter readings as a measure of smoking was obtained by a specially designed participant‐observer technique. It was found that the rate of smoking decreased as a function of the intensity of the shock. Also, the smoking returned to its previously unpunished level after the shock punisher was discontinued. Both of these findings confirm the results of laboratory studies of punishment of simpler responses and extends them to more complex responses in a naturalistic situation. Surprisingly, the duration for which the apparatus was worn also decreased as a function of the intensity of the shock. This finding reveals that this aversive shock technique produced avoidance behavior that prevents the technique from having extensive applicability for eliminating smoking. The same limitation may apply to the use of aversive shock for eliminating other undesirable behaviors.

Terrace suggested that the peak shift in stimulus generalization occurs because the training stimulus not correlated with reinforcement has become aversive. This hypothesis is plausible in the light of instances where the peak shift is obtained compared with those where it fails to appear. The present experiment attempted to test implications of this hypothesis. Two groups of pigeons learned the same two‐stimulus discrimination between colors by different training methods in a free‐operant situation. When the discrimination was trained with many errors, a large peak shift was obtained in a subsequent generalization test of wavelength; after discrimination training with few errors, a negligible shift was observed. Half of each group then received noncontingent aversive shock during presentations of the stimulus not correlated with reinforcement in continued discrimination training. After this treatment, the errorless‐shock subgroup showed a large peak shift and the error‐shock subgroup tended to show a larger shift than before. Nonshocked control groups showed little change in the peak shift. It was concluded that pairing aversive shock with a stimulus not correlated with reinforcement is sufficient to produce or enhance a peak shift. In their effect on the peak shift, aversive shock and large amounts of nonreinforced responding appear to be equivalent.

In a multiple schedule, exteroceptive stimuli change when the reinforcement schedule is changed. Each performance in a multiple schedule may be considered concurrent with other behavior. Accordingly, two variable‐interval schedules of reinforcement were arranged in a multiple schedule, and a third, common variable‐interval schedule was programmed concurrently with each of the first two. A quantitative statement was derived that relates as a ratio the response rates for the first two (multiple) variable‐interval schedules. The value of the ratio depends on the rates of reinforcement provided by those schedules and the reinforcement rate provided by the common variable‐interval schedule. The following implications of the expression were evaluated in an experiment with pigeons: (a) if the reinforcement rates for the multiple variable‐interval schedules are equal, then the ratio of response rates is unity at all reinforcement rates of the common schedule; (b) if the reinforcement rates for the multiple schedules are unequal, then the ratio of response rates increases as the reinforcement rate provided by the common schedule increases; (c) the limit of the ratio is equal to the ratio of the reinforcement rates. Satisfactory confirmation was obtained for the first two implications, but the third was left in doubt.

Monkeys were trained with food reinforcement in a chamber containing four groups of three levers. For each session the monkey's task was to learn a new four‐response chain by pressing the correct lever in each group. A stable pattern of learning resulted, and the number of errors reached a steady state from session to session. The technique was then used to determine how various durations of timeouts, following errors, affected the acquisition of new chains. With no timeout, the monkeys made a great many errors, due in large part to superstitious responses within the reinforced chain. Timeout durations ranging from 1 sec to 4 min reduced the number of errors substantially. A second experiment investigated the effects upon acquisition errors of presenting a single light (an “instruction” stimulus) over the correct lever. When this light did not influence the monkeys' responses to the three alternatives, the chains were learned as without it. When the light did control responding, the monkey pressed the appropriate sequence of levers but did not learn the sequence. Thus, when the light was removed, the monkey performed as if learning that sequence for the first time.

Adult social reinforcement and access to materials in the preschool were made contingent on the verbalizations of a 4‐yr‐old Negro girl with an extremely low frequency of talking. Though the teachers' social attention was always given immediately for all spontaneous speech, if the child's spontaneous verbalizations were requests for materials, those materials were withheld until she had responded to the teachers' questions about those materials. When she was silent, the teachers withheld their attention and the materials. A high frequency of verbal behavior was quickly established. When both teacher attention and materials were provided only when the child was not verbalizing, the child's frequency of talking immediately decreased. When social attention and materials were again made contingent upon spontaneous speech and answering questions, the child's frequency of talking quickly increased to its previous high level. The content of the child's verbal behavior which increased was primarily a repetition of requests to the teachers with little change noted in the non‐request verbalizations, or verbalizations to other children. A further experimental analysis demonstrated that social interaction per se was not the reinforcer which maintained the increased verbalization; rather, for this child, the material reinforcers which accompanied the social interaction appeared to be the effective components of teacher attention.

Interresponse time distributions of the terminal rate under fixed‐interval and fixed‐ratio schedules were examined, using data from three rats in each case. By means of a sequential analysis, the overall interresponse time distributions were separated into orderly components. Consideration of the component distributions suggested that multiple determinants of rate act in succession, not simultaneously, and that probability of reinforcement has an important effect on the probability of occurrence of interresponse times.

Individual conditioning techniques were applied in a controlled setting to increase attending behavior of an underachieving 9‐yr‐old male subject. The procedure involved: (1) determining a stable response pattern, (2) introducing a treatment variable to establish a high rate of task‐attending behavior, (3) measuring the effect of withdrawal of the treatment variable after attaining criterion performance, and (4) transferring control to the classroom. The interval of attending behavior required for reinforcement was systematically increased from 30 sec to 600 sec as the behavior came under experimental control. Manipulating the reinforcing contingencies measurably changed the proportion of attending behavior and the frequency and duration of non‐attending events. Once the behaviors were under experimental control, procedures were established to program generalization and to maintain the behavior outside the experimental setting.

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