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The self‐injurious behavior (SIB) of a blind, profoundly retarded male was observed within a field setting as multiple forms of punishment were applied. The effects of hair‐tug punishment were first systematically examined, then hair‐tug and electric shock punishment were administered in varing ratios (of punishment deliveries per SIB response) supplemented by continuous restraint contingencies and made contingent on recurrent antecedents of SIB cycles. Treatments were applied over six months of consecutive daily sessions ranging from 30 min to 8 hr duration. Posttreatment followup observations were taken 12, 24, and 34 months after treatment. Partial suppression was produced as a direct function of hair‐tug punishment in the initial phase. A generally progressive decrement was produced on already lowered SIB rates with the succeeding components of the treatment package. Extended periods of total SIB suppression occurred as punishment was rendered contingent on antecedent components of each SIB response cycle. Followup observations of nearly 3 yr duration indicated total suppression generalized over all settings in which the subject functioned. The findings were related to the contrasting limits prevailing in most reports of punishment‐based SIB suppression.

Four White King pigeons pressed treadles for food reinforcement on several concurrent variable‐interval variable‐interval schedules. The rate of reinforcement available for responding in one of the two component schedules was held constant at 30 reinforcers per hour. The rate of reinforcement available for responding in the other was varied from 120 to 60 to 15, and then to 30 reinforcers per hour. The relative rate of responding in each component schedule equalled the relative rate of reinforcement that the component provided. And, behavioral contrast, defined as an inverse relationship between the rate of responding in the constant component and the rate of reinforcement obtained by responding in the other component, occurred for all schedules.

Pigeons on concurrent variable‐ratio variable‐ratio schedules usually, though not always, maximize reinforcements per response. When the ratios are equal, maximization implies no particular distribution of responses to the two alternatives. When the ratios are unequal, maximization calls for exclusive preference for the smaller ratio. Responding conformed to these requirements for maximizing, which are further shown to be consistent with the conception of reinforcement implicit in the matching law governing relative responding in concurrent interval schedules.

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In an attempt to control gastric acid secretion with operant‐conditioning techniques, four normal women were given visual feedback on gastric pH plus money reinforcers. When money was made dependent on increased secretion in a differential‐reinforcement‐of‐high‐rates schedule, the rate of secretion of three of the four subjects increased to three times baseline. When money was then made dependent on decreased secretion in a differential‐reinforcement‐of‐other‐behaviors schedule, the rate of secretion of these three subjects returned to baseline levels. Heart rate, respiratory frequency, abdominal electromyographic activity, and stomach motility (measured by the electrogastrogram method) were not consistently correlated with acid secretion across subjects, although individual subjects showed substantial correlations between acid secretion and one or more other physiological response.

This study investigated the effects of interruption and differential reinforcement on seizures in children. Seizures were conceptualized as the terminal link in a behavioral chain, resulting in a strategy aimed at identifying and modifying behaviors that reliably preceded the seizure climax. Seizure frequency was reduced in four of five subjects, whereas the frequency of preseizure behavior was reduced in only three subjects. Parents and school personnel were successfully used as change agents.

Children from regular and special‐education classes were exposed to tutoring procedures designed to modify letter and number reversals. In Experiment I, two students showed reversals during letter‐naming (e.g., saying p for q) and two‐digit number (e.g., writing 31 for 13) exercises. In Experiment II, one subject made two‐digit reversals, while the other child reversed single‐digit numbers (e.g., 9 written with circle on right side of stem). The subject in Experiment III emitted letter reversals under naming, dictation, and copying exercises. The child in Experiment IV showed written letter reversals on both sides of the “body midline” under dictation procedures. Basic treatment procedures during all experiments involved modelling of correct and incorrect symbol formation, and differential experimenter feedback following student responses. During Experiments I and II, subjects were praised for each correct response, and informed when a reversal occurred. Experiment III included a Modelling Only Phase before these feedback procedures. Besides praise, treatment conditions in Experiment IV consisted of additional feedback following correct responses (e.g., charting correct responses), and temporal delays imposed between dictated letters and student responses. Except for occasional letter‐naming reversals of one subject (Experiment I), and letter dictation errors of another (Experiment IV), reversals were eliminated when all experiments terminated. The Modelling Only Phase in Experiment III also reduced reversals to a low level. These findings suggest that a variety of reversal problems may be effectively assessed and remediated via simple modelling and reinforcement procedures. In addition, postcheck observations indicated that the effects were enduring. The present procedures should be easily implemented by school personnel.

Pigeons obtained food by responding in a discrete‐trials two‐choice probability‐learning experiment involving temporal stimuli. A given response alternative, a left‐ or right‐key peck, had 11 associated reinforcement probabilities within each session. Reinforcement probability for a choice was an increasing or a decreasing function of the time interval immediately preceding the choice. The 11 equiprobable temporal stimuli ranged from 1 to 11 sec in 1‐sec classes. Preference tended to deviate from probability matching in the direction of maximizing; i.e., the percentage of choices of the preferred response alternative tended to exceed the probability of reinforcement for that alternative. This result was qualitatively consistent with probability‐learning experiments using visual stimuli. The result is consistent with a molecular analysis of operant behavior and poses a difficulty for molar theories holding that local variations in reinforcement probability may safely be disregarded in the analysis of behavior maintained by operant paradigms.

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