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Correspondence was developed between children's non‐verbal and verbal behavior such that their non‐verbal behavior could be altered simply by reinforcing related verbal behavior. Two groups of six children each were given food snack at the end of the day: for reporting use of a specific preschool material during free play (procedure A); and then only for reports of use which corresponded to actual use of that material earlier that day (procedure B). Initially, procedure A alone had little or no effect on the children's use of materials. Procedure B resulted in all of the children in one group actually using a specific material, and after repeating procedures A and B with this group across a series of different materials, procedure A alone was sufficient to significantly increase use of a specific material. Correspondence between verbal and non‐verbal behavior was produced such that, in this group of 4‐yr‐old disadvantaged Negro children, “saying” controlled “doing” 22 or more hours later. In the second group, procedure B initially did not increase the use of a specific material; rather, the children's reports decreased so as to correspond to the intermittent use of the material. It appeared from subsequent procedures with this group that maintenance of a high level of reporting was crucial to the saying‐then‐doing correspondence seen in the first group.

A training technique has been developed which combines classical differential conditioning and conditional emotional response (CER) procedures. After monkeys were trained to lever‐press on a variable‐interval schedule, two stimulus lights were presented. One light (CS) was always followed, upon termination, by electrical shock; the other light (DS) was never followed by shock. The response to the CS was a decreased rate of lever‐pressing and increased heart rate and blood‐flow velocity. None of these responses occurred to the DS. This technique eliminates the possibility of pseudoconditioning and provides measurement of both somatic and autonomic responses in a CER situation.

Pigeons were trained to respond with equal variable‐interval reinforcement in the presence of a white key and also a white key with a vertical line. They were then trained not to respond to the vertical line by extinguishing the response or by reinforcing its non‐occurrence at various frequencies. During training, the rate of key‐pecking in the presence of the white key, maintained by a constant variable‐interval schedule of reinforcement, depended on the frequency of reinforcement in the presence of the line. When lines of different orientations were presented in a generalization test, birds trained with extinction responded more to other orientations than to the vertical line, whereas those trained with high frequencies of reinforcement for not responding tended to respond equally at all line orientations. Intermediate frequencies of reinforcement gave mixed results.

A discrimination between two successively alternating stimuli was trained under conditions that maintained equal frequencies of reinforcement in the presence of each of the discriminative stimuli (S1 and S2) but that also reduced the rate of responding to S2. These conditions included a multiple variable‐interval differential‐reinforcement‐of‐low‐rate schedule and a multiple variable‐interval variable‐interval schedule in which responses to S2 were punished. Whenever the rate of responding to S2 was reduced, rate of responding to S1 (behavioral contrast) increased, and the peak of a subsequently obtained generalization gradient did not occur at the expected location (between S1 and S2) but was displaced away from S2, below S1. Discrimination training in which the frequencies of reinforcement earned in S1 and S2 were not equal (variable‐interval 1‐min variable‐interval 5‐min training) produced contrast and the peak shift only if the rate of responding to S2 had been reduced, as after non‐differential reinforcement in which variable‐interval 1‐min schedules were correlated with SI and with S2. It was concluded that a sufficient condition for the occurrence of behavioral contrast and the peak shift was reduction of the rate of responding to one of two alternating discriminative stimuli and that a peak shift will occur only if contrast had occurred during discrimination training.

Rats were trained to respond to the brighter of two keys. Four animals were trained with food pellets and four with electrical brain stimulation. Each discrimination sequence was initiated when the animal broke a light beam at the rear of the chamber, turning on the key lights and starting a 30‐sec reinforcement period. An initial response on the brighter key was immediately reinforced, and further responses on the brighter key were then intermittently reinforced. Any time the dimmer key was pressed, a 30‐sec timeout was introduced. During timeout, no response had any programmed consequence. When the reinforcement period or the timeout ended, a new discrimination sequence could be initiated. Daily 1‐hr training sessions were conducted, and after seven or eight sessions, all animals were at or near errorless performance levels. The luminance of the brighter key was then systematically reduced, in seven steps, with two 30‐min test sessions at each step. Orderly psychometric functions were generated for individual animals. Initial acquisition, once position preferences were broken, was equally rapid for food and for brain‐stimulation animals, and the two reinforcement procedures yielded comparable levels of brightness discriminability.

Four white rats were trained to avoid electric shocks by depressing a bar after the onset of a stimulus and releasing it after termination of the stimulus. All subjects acquired the behavior of holding the bar in the presence of the stimulus and releasing it in the absence of the stimulus, but one animal almost always required a “priming” shock. The others exhibited a high level of shock avoidance.

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The effect of adult social reinforcement on the cooperative play of a five‐year old girl in a preschool setting was assessed under two conditions: (1) presented randomly throughout the school day, and (2) presented contingent on cooperative play. Only in the latter condition was a significant change in cooperative play observed.

Two monkeys (Macaca mulatta) were trained to perform an oddity discrimination using automatically projected patterned stimuli. After criteria for both response and discrimination stability were met, a tone followed by shock was superimposed upon the ongoing behavior. Each 60‐sec tone was terminated with the onset of a 0.3‐sec, 1 to 1.5‐ma electric shock. During the tone, baseline responding was partially suppressed but discrimination performance was little altered from the pre‐tone period. When shock was raised to 2 to 3 ma, responding was further suppressed, but discrimination performance was again essentially unaltered.