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Unproductive classroom behavior was eliminated in two emotionally disturbed boys by removing social consequences of the behavior. Behavior which was more adequate and efficient with respect to social and scholastic adjustment was shaped and maintained with social reinforcers.

Six 4‐year‐old Ss were presented with a textual program consisting of 26 words arranged so the word stimuli were gradually combined into sentences and then short “stories.” Three Ss were given the No‐Reinforcement condition first, and only social reinforcers were presented. They were switched to the Reinforcement condition as soon as they requested discontinuance of the activity. The other three Ss were given Reinforcement—No Reinforcement—Reinforcement treatments. The No‐Reinforcement treatment in this case lasted until S requested discontinuance of the activity. The reinforcers were mixed edibles and trinkets, as well as tokens backed up by small plastic toys on a 1:24 ratio. The unit of response was the number of new texts acquired as a result of each of the 45‐min experimental sessions. It was demonstrated that the program, procedure, and reinforcement conditions produced curves which are analogous to those produced in common operant‐conditioning procedures. The results indicate that other operant principles may be studied in this significant area of human behavior, with important practical consequences.

Of 23 pigeons, 11 received continuous reinforcement for key pecking, and 12 received an FR 10 schedule of reinforcement. The birds were then tested without food, but with potential conditioned reinforcers presented either on the same schedule as in training, on the other schedule, or not at all. Each bird in the subgroup trained on CRF and tested with Sr's at FR 10 not only gave more responses in testing than did each bird in both subgroups receiving no Sr's, but also gave more responses than did each bird in the Sr subgroup receiving CRF training and Sr's at CRF. Cumulative records are presented to show the effects of different schedules of conditioned reinforcers.

Pecking was reinforced by a fixed‐ratio schedule with food, and responses during a red light produced a time out. If the bird did not respond during the red light, the light terminated and the bird could complete the FR schedule of positive reinforcement uninterrupted. The bird stopped responding during the red light sufficiently to avoid most of the possible time outs. In general, the pre—time‐out stimulus suppressed responding more when the FR schedule was large than when it was small. The occurrence of the pre—time‐out stimulus in the fixed ratio produced FR strain and extreme curvature atypical of normal fixed ratios of this size. Amobarbital, pentobarbital, chlorpromazine, and d‐amphetamine injected when the FR performance was strained by the pre—time‐out procedure produced marked increases in responding. The drug administration lowered the rate of responding only at larger doses; and then this occurred predominantly just after the injection.

The effect of repeated interruption of FI responding by short SΔ presentations on the pattern of increasing frequency of responding through the interval has been studied. Although the SΔ profoundly changed the pattern of responding during their presentation, the general scalloped pattern of FI responding survived. The implication of these findings for understanding the role of chaining of responses in FI patterns is discussed. It is suggested that chaining is not a necessary condition for the scalloped pattern.

Investigations are reported of some of the discriminative (cue) and reinforcing properties of stimuli (TOav) correlated with the discontinuation of a free‐operant avoidance schedule. After several unsuccessful initial attempts to demonstrate the positively reinforcing effect of TOav, a special technique was developed. The subjects were trained by means of a free‐operant avoidance procedure to press a lever and postpone electric shock; by pressing a second lever, they could produce a cue correlated with the TOav period. The importance of a distinct cue correlated with TOav was demonstrated in experiments in which this signal was eliminated from the procedure. The reinforcing function of the TOav period was explored by showing its effectiveness under various schedules of reinforcement.Other observations were made concerning the course of extinction of both TOav‐producing responses and avoidance behavior.In further experiments in which TOav was used as a reinforcer, the TOav behavior was also brought under separate stimulus control. The development of the various discriminations involved in the resulting performance were described.

Human conversation is a natural place to begin the study of social responses. In a conversation, a number of individuals use one another's responses as cues for their own behavior. So long as a conversation is being held, the speakers must talk in some order. Four experiments were conducted to test whether differentially reinforcing a group of speakers can bring the order of speakers under experimental control. The results are all consistent with the hypothesis. The paper also devises and evaluates different procedures for studying conversational sequences and examines associated statistical problems.

Control over the vocal responses of three dogs was established using operant‐conditioning procedures. Several points of interest were observed in the data. First, fixed‐ratio schedules of reinforcement generated a vocal response topography which was similar in detail to that of a “motor” bar‐nosing response. Second, vocal responding was brought under the control of external visual stimuli as a result of differential reinforcement. Third, good stimulus control was maintained on a multiple schedule containing a vocal‐response component and a bar‐response component. Fourth, the stimulus control on the multiple schedule transferred with minimal disruption to a chain schedule requiring a sequence of 10 bar responses followed by 10 vocal responses. Fifth, because vocal and bar responses are not mutually exclusive, concurrent responding tended to develop on the chain schedule.These results were discussed with reference to the advisability of applying the terms operant and respondent to unconditioned behavior, and, particularly, to unconditioned verbal behavior.