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No method is in general usage and of demonstrated effectiveness in eliminating the self‐stimulatory behaviors of retardates and autistics. An Overcorrection rationale was used to develop such a method. The Overcorrection procedures consisted of a period of practice in the correct mode of the behavior contingent upon self‐stimulatory behavior. The procedures were applied in a behavioral day‐care program to three retarded children and one autistic child who exhibited object‐mouthing, hand‐mouthing, head‐weaving and hand‐clapping. For some behaviors, comparisons were made between the Overcorrection procedure and several alternative procedures, such as physical punishment by a slap, reinforcement for nonself‐stimulatory behavior, a distasteful solution painted on the hand of a hand‐mouther, and free reinforcement. The Overcorrection procedures eliminated the self‐stimulatory behaviors of all four children in tutorial sessions and during the entire school day and were more effective than the alternative procedures in eliminating self‐stimulation. The Overcorrection procedures appear to be rapid, enduring, and effective methods of eliminating self‐stimulatory behavior.

Pigeons were trained to discriminate a slow click‐rate from its absence, or to discriminate it from a faster click‐rate. Subsequent click‐rate generalization tests produced the usual steepened gradients after the intradimensional discrimination but produced flat gradients after presence/absence discrimination. The occurrence of stimulus control only after intradimensional discrimination, combined with previous results showing stimulus control sometimes after nondifferential reinforcement and sometimes after presence/absence discrimination, argues for a reformulation of the problem of stimulus control. A theoretical framework, relying upon blocking effects inherent in the different discrimination procedures, was presented to account for the diversity of results.

The relation between the form of auto‐shaped responses to the lighting of a key and the consummatory responses of pecking grain and drinking water was examined in pigeons. Responses on the key were analyzed by means of high‐speed photography, recordings of the force of contact, and judges' ratings of response‐form based on film and videotape recordings. The first experiment showed that food‐deprived birds presented grain as a reinforcer responded on the key with a grain‐pecking movement, while water‐deprived birds presented water as a reinforcer responded with drinking‐like movements. The second and third experiments showed that the resemblance between auto‐shaped and consummatory responses does not require the dominance of the deprivational state appropriate to the reinforcer. Changing the dominant state of deprivation did not immediately change the form of the key response, and in subjects simultaneously deprived of food and water, the form of response depended on the reinforcer. In the fourth and fifth experiments, subjects simultaneously deprived of food and water received one stimulus signalling food and another signalling water in a random series. In most subjects, the response to each stimulus resembled the consummatory response to the particular reinforcer that was signalled by the stimulus. This result demonstrates the role of association between a stimulus and a reinforcer in producing a resemblance of the auto‐shaped response to the consummatory response.

Three naive pigeons were exposed to a series of two‐component multiple schedules of response‐independent food presentation. The component schedules were sometimes identical (non‐differential procedures) and sometimes different (differential procedures). High rates of key pecking were maintained in all the differential procedures, and pecking decreased substantially in non‐differential procedures, even when the frequency of food presentation in non‐differential procedures was higher than in differential procedures. It is suggested that the high rates of key pecking were maintained not by adventitious response‐reinforcer contingencies, but by differential contingencies between the stimulus (keylight) and food. The role of such contingencies in the phenomenon of behavioral contrast is discussed.

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The present study objectively defined and manipulated some compositional variables in 10‐sentence stories written by fourth‐, fifth‐, and sixth‐grade students, and related these operationally defined variables to subjective judgements of creativity. Points, exchangeable for candy and extra recess, were given to members of two teams contingent upon their using different adjectives, different action verbs, and different sentence beginnings. The students' use of these selected parts of speech was modified and the independent subjective ratings indicated that stories written during contingency conditions were generally rated as more creative than those written during baseline conditions. Operational definitions that specify non‐repetition or variety of responses, and contingencies that require response diversity may provide a beginning basis for defining writing creativity and the conditions that maximize its occurrence.

Six rats were trained on a two‐component multiple schedule with each component consisting of a two‐link chain schedule. Differential response suppression in the two initial links, as well as in the two terminal links of the chain schedules, was used as a measure of the relative aversiveness of stimulus events in the two terminal links. When signalled and unsignalled shock‐punishment (in addition to equal numbers of food reinforcers) were scheduled in the separate terminal links, subjects responded at lower rates in the initial link preceding unsignalled shock‐punishment than in the initial link preceding signalled shock‐punishment. Similarly, subjects responded at lower rates in the terminal link containing unsignalled shock‐punishment than in the terminal link containing signalled shock‐punishment. Reversing the terminal‐link positions of signalled and unsignalled shock‐punishment led to a reversal of the differential response suppression in the two initial and the two terminal links of the chain schedules. These results indicate that signalled punishment is relatively less aversive than unsignalled punishment and support an “information hypothesis”, which assumes that a condition in which information is provided about the onset of environmental events, even negative events such as shock punishment, is more reinforcing than a condition in which such information is absent.

A grade‐four class teacher was trained in the use of token and verbal reinforcement by an experienced “token helper”, who demonstrated the procedures in the classroom. The introduction of a simple token system resulted in significant decreases in the disruptive behavior of 10 pupils in two morning periods. When the token helper withdrew from the classroom, the teacher managed the token system and maintained disruptive behavior at lower than baseline levels.

Pigeons' standing on one or the other side of a chamber was reinforced with timeout from electric shock on two concurrent variable‐interval schedules. For two pigeons, the ratio of time spent on the left to time spent on the right approximately matched the ratio of timeouts obtained on the left to timeouts obtained on the right. The data of two other birds deviated from this relation, although in opposite directions. Overall, the results suggest that reduction in rate of electric shock plays a role in behavioral allocation analogous to that played by rate of positive reinforcement. It appears possible to describe aversive control and positive control within the same conceptual framework—that provided by the matching relation.

The effectiveness of a brief period of isolation (timeout) in the control of disruptive behavior emitted by a retarded child in a preschool classroom setting was examined. Timeout was shown to be an effective punishing stimulus, and its control of the child's disruptive behavior was investigated under four schedules of intermittent timeout. The results suggest that as a larger percentage of responses were punished, a greater decrease in the frequency of that response occurred. This inverse relationship between the percentage of responses punished and the frequency of the response did not appear to be linear, but rather a non‐linear function. This function suggests that some schedules of intermittent punishment may be as effective as continuous punishment, at least in the case of the continued suppression of a response that has already been reduced to a low frequency.